By Monish Raj, Assistant Manager-Technical Services, EW Nutrition
Inge Heinzl, Editor, EW Nutrition  

Mycotoxins, toxic secondary metabolites produced by fungi, are a constant and severe threat to animal production. They can contaminate grains used for animal feed and are highly stable, invisible, and resistant to high temperatures and normal feed manufacturing processes. Mycotoxin-producing fungi can be found during plant growth and in stored grains; the prevalence of fungi species depends on environmental conditions, though in grains, we find mainly three genera: Aspergillus, Penicillium, and Fusarium. The most critical mycotoxins for poultry production and the fungi that produce them are detailed in Fig 1.

Figure 1: Fungi species and their mycotoxins of worldwide importance for poultry production (adapted from Bryden, 2012).

The effects of mycotoxins on the animal are manifold

When, usually, more than one mycotoxin enters the animal, they “cooperate” with each other, which means that they combine their effects in different ways. Also, not all mycotoxins have the same targets.

The synergistic effect: When 1+1 ≥3

Even at low concentrations, mycotoxins can display synergistic effects, which means that the toxicological consequences of two or more mycotoxins present in the same sample will be higher than the sum of the toxicological effects of the individual mycotoxins. So, disregarded mycotoxins can suddenly get important due to their additive or synergistic effect.

Table 1: Synergistic effects of mycotoxins in poultry

Table 2: Additive effects of mycotoxins in poultry

Recognize the effects of mycotoxins in animals is not easy

The mode of action of mycotoxins in animals is complex and has many implications. Research so far could identify the main target organs and effects of high levels of individual mycotoxins. However, the impact of low contamination levels and interactions are not entirely understood, as they are subtle, and their identification requires diverse analytical methods and closer observation.

With regard to the gastrointestinal tract, mycotoxins can inhibit the absorption of nutrients vital for maintaining health, growth, productivity, and reproduction. The nutrients affected include amino acids, lipid-soluble vitamins (vitamins A, D, E, and K), and minerals, especially Ca and P (Devegowda and Murthy, 2005). As a result of improper absorption of nutrients, egg production, eggshell formation, fertility, and hatchability are also negatively influenced.

Most mycotoxins also have a negative impact on the immune system, causing a higher susceptibility to disease and compromising the success of vaccinations. Besides that, organs like kidneys, the liver, and lungs, but also reproduction, endocrine, and nervous systems get battered.

Mycotoxins have specific targets

Aflatoxins, fumonisins, and ochratoxin impair the liver and thus the physiological processes modulated and performed by it:

• lipid and carbohydrate metabolism and storage
• synthesis of functional proteins such as hormones, enzymes, and nutrient transporters
• metabolism of proteins, vitamins, and minerals.

For trichothecenes, the gastrointestinal tract is the main target. There, they hamper digestion, absorption, and intestinal integrity. T-2 can even produce necrosis in the oral cavity and esophagus.

Figure 2: Main target organs of important mycotoxins

How to reduce mycotoxicosis?

There are two main paths of action, depending on whether you are placed along the crop production, feed production, or animal production cycle. Essentially, you can either prevent the formation of mycotoxins on the plant on the field during harvest and storage or, if placed at a further point along the chain, mitigate their impact.

Preventing mycotoxin production means preventing mold growth

To minimize the production of mycotoxins, the development of molds must be inhibited already during the cultivation of the plants and later on throughout storage. For this purpose, different measures can be taken:

Selection of the suitable crop variety, good practices, and optimal harvesting conditions are half of the battle

Already before and during the production of the grains, actions can be taken to minimize mold growth as far as possible:

• Choose varieties of grain that are area-specific and resistant to insects and fungal attacks.
• Practice crop rotation
• Harvest proper and timely
• Avoid damage to kernels by maintaining the proper condition of harvesting equipment.

Optimal moisture of the grains and the best hygienic conditions are essential

The next step is storage. Here too, try to provide the best conditions.

• Dry properly: grains should be stored at <13% of moisture
• Control moisture: minimize chances of moisture to increase due to condensation, and rain-water leakage
• Biosecurity: clean the bins and silos routinely.
• Prevent mold growth: organic acids can help prevent mold growth and increase storage life.

Mold production does not mean that the war is lost

Even if molds and, therefore, mycotoxins occur, there is still the possibility to change tack with several actions. There are measures to improve feed and support the animal when it has already ingested the contaminated feed.

1.    Feed can sometimes be decontaminated

If a high level of mycotoxin contamination is detected, removing, replacing, or diluting contaminated raw materials is possible. However, this is not very practical, economically costly, and not always very effective, as many molds cannot be seen. Also, heat treatment does not have the desired effect, as mycotoxins are highly heat stable.

2.    Effects of mycotoxins can be mitigated

Even when mycotoxins are already present in raw materials or finished feed, you still can act. Adding products adsorbing the mycotoxins or mitigating the effects of mycotoxins in the organism has been considered a highly-effective measure to protect the animals (Galvano et al., 2001).

This type of mycotoxin mitigation happens at the animal production stage and consists of suppressing or reducing the absorption of mycotoxins in the animal. Suppose the mycotoxins get absorbed in the animal to a certain degree. In that case, mycotoxin mitigation agents help by promoting the excretion of mycotoxins, modifying their mode of action, or reducing their effects. As toxin-mitigating agents, the following are very common:

Aluminosilicates: inorganic compounds widely found in nature that are the most common agents used to mitigate the impact of mycotoxins in animals. Their layered (phyllosilicates) or porous (tectosilicates) structure helps “trap” mycotoxins and adsorbs them.

• Bentonite / Montmorillonite: classified as phyllosilicate, originated from volcanic ash. This absorbent clay is known to bind multiple toxins in vivo. Incidentally, its name derives from the Benton Shale in the USA, where large formations were discovered 150 years ago.
  Bentonite mainly consists of smectite minerals, especially montmorillonite (a layered silicate with a larger surface area and laminar structure).

• Zeolites: porous crystalline tectosilicates, consisting of aluminum, oxygen, and silicon. They have a framework structure with channels that fit cations and small molecules. The name “zeolite” means “boiling stone” in Greek, alluding to the steam this type of mineral can give off in the heat). The large pores of this material help to trap toxins.

Activated charcoal: the charcoal is “activated” when heated at very high temperatures together with gas. Afterward, it is submitted to chemical processes to remove impurities and expand the surface area. This porous, powdered, non-soluble organic compound is sometimes used as a binder, including in cases of treating acute poisoning with certain substances.

Yeast cell wall: derived from Saccharomyces cerevisiae. Yeast cell walls are widely used as adsorbing agents. Esterified glucomannan polymer extracted from the yeast cell wall was shown to bind to aflatoxin, ochratoxin, and T-2 toxin, individually and combined (Raju and Devegowda 2000).

Bacteria: In some studies, Lactic Acid Bacteria (LAB), particularly Lactobacillus rhamnosus, were found to have the ability to reduce mycotoxin contamination.

Which characteristics are crucial for an effective toxin-mitigating solution

If you are looking for an effective solution to mitigate the adverse effects of mycotoxins, you should keep some essential requirements:

1. The product must be safe to use:
   1. safe for the feed-mill workers.
   2. does not have any adverse effect on the animal
   3. does not leave residues in the animal
   4. does not bind with nutrients in the feed.
2. It must show the following effects:
   1. effectively adsorbs the toxins relevant to your operation.
   2. helps the animals to cope with the consequences of non-bound toxins.
3. It must be practical to use:
   1. cost-effective
   2. easy to store and add to the feed.

Depending on

• the challenge (one mycotoxin or several, aflatoxin or another mycotoxin),
• the animals (short-cycle or long-living animals), and
• the economical resources that can be invested,

different solutions are available on the market. The more cost-effective solutions mainly contain clay to adsorb the toxins. Higher-in-price products often additionally contain substances such as phytogenics supporting the animal to cope with the consequences of non-bound mycotoxins.

Solis – the cost-effective solution

In the case of contamination with only aflatoxin, the cost-effective solution Solis is recommended. Solis consists of well-selected superior silicates with high surface area due to its layered structure. Solis shows high adsorption of aflatoxin B1, which was proven in a trial:

Figure 3: Binding capacity of Solis for Aflatoxin

Even at a low inclusion rate, Solis effectively binds the tested mycotoxin at a very high rate of nearly 100%. It is a high-efficient, cost-effective solution for aflatoxin contamination.

Solis Max 2.0: The effective mycotoxin solution for sustainable profitability

Solis Max 2.0 has a synergistic combination of ingredients that acts by chemi- and physisorption to prevent toxic fungal metabolites from damaging the animal’s gastrointestinal tract and entering the bloodstream.

Figure 4: Composition and effects of Solis Max 2.0

Solis Max 2.0 is suitable for more complex challenges and longer-living animals: in addition to the pure mycotoxin adsorption, Solis Max 2.0 also effectively supports the liver and, thus, the animal in its fight against mycotoxins.

In an in vitro trial, the adsorption capacity of Solis Max 2.0 for the most relevant mycotoxins was tested. For the test, the concentrations of Solis Max 2.0 in the test solutions equated to 1kg/t and 2kg/t of feed.

Figure 5: Efficacy of Solis Max 2.0 against different mycotoxins relevant in poultry production

The test showed a high adsorption capacity: between 80% and 90% for Aflatoxin B1, T-2 Toxin (2kg/t), and Fumonisin B1. For OTA, DON, and Zearalenone, adsorption rates between 40% and 80% could be achieved at both concentrations (Figure 5). This test demonstrated that Solis Max 2.0 could be considered a valuable tool to mitigate the effects of mycotoxins in poultry.

Broiler trial shows improved performance in broilers

Protected and, therefore, healthier animals can use their resources for growing/laying eggs. A trial showed improved liver health and performance in broilers challenged with two different mycotoxins but supported with Solis Max 2.0.

For the trial, 480 Ross-308 broilers were divided into three groups of 160 birds each. Each group was placed in 8 pens of 20 birds in a single house. Nutrition and management were the same for all groups. If the birds were challenged, they received feed contaminated with 30 ppb of Aflatoxin B1 (AFB1) and 500 ppb of Ochratoxin Alpha (OTA).

The body weight and FCR performance parameters were measured, as well as the blood parameters of alanine aminotransferase and aspartate aminotransferase, both related to liver damage when increased.

Concerning performance as well as liver health, the trial showed partly even better results for the challenged group fed with Solis Max 2.0 than for the negative, unchallenged control (Figures 6 and 7):

• 6% higher body weight than the negative control and 18.5% higher body weight than the challenged group
• 12 points and 49 points better FCR than the negative control and the challenged group, respectively
• Lower levels of AST and ALT compared to the challenged group, showing a better liver health

The values for body weight, FCR, and AST, even better than the negative control, may be owed to the content of different gut and liver health-supporting phytomolecules.

Figure 6: Better performance data due to the addition of Solis Max 2.0

Figure 7: Healthier liver shown by lower values of AST and ALT

Effective toxin risk management: staying power is required

Mycotoxin mitigation requires many different approaches. Mycotoxin mitigation starts with sewing the appropriate plants and continues up to the post-ingestion moment. From various studies and field experience, we find that besides the right decisions about grain crops, storage management, and hygiene, the use of effective products which mitigate the adverse effects of mycotoxins is the most practical and effective way to maintain animals healthy and well-performing. According to Eskola and co-workers (2020), the worldwide contamination of crops with mycotoxins can be up to 80% due to the impact of climate change and the availability of sensitive technologies for analysis and detection. Using a proper mycotoxin mitigation program as a precautionary measure is, therefore, always recommended in animal production.

Toxin Risk Management

EW Nutrition’s Toxin Risk Management Program supports farmers by offering a tool (MasterRisk) that helps identify and evaluate the risk and gives recommendations concerning using toxin solutions.

by Inge Heinzl, Editor, and Marisabel Caballero, Global Technical Manager Poultry, EW Nutrition

What is your most crucial key feed performance indicator? We posted this question on an online professional platform and got more than 330 answers from professionals in the industry:

• 55 % of the respondents considered feed efficiency or feed conversion rate (FCR) the key indicator, and
• 35 % listed feed cost / kg produced as their most important indicator.

As feed represents 60-70 % of the total production costs, feed efficiency has a high impact on farm profitability – especially in times of high feed prices. Furthermore, for the meat industry, an optimal FCR is essential for competitiveness against other protein sources. Finally, for food economists, feed efficiency is connected to the optimal use of natural resources (Patience et al., 2015).

In this article, we explain the factors that influence feed efficiency and show options to support animals in optimally utilizing the feed – directly improving the profitability of your operation.

How to measure the feed conversion rate

The FCR shows how efficiently animals utilize their diet for maintenance and net production. In the case of fattening animals, it is meat production; for dairy cows, it is milk, and for layers, it is egg mass (kg) or a specific egg quantity.

The feed conversion rate is the mathematical relation obtained by dividing the amount of feed the animal consumed by the production it provided. The FCR is an index for the degree of feed utilization and shows the amount of feed needed by the animal to produce one kg of meat or egg mass, or, e.g., 10 eggs.

When comparing the FCRs of different groups of animals (e.g., from different houses or farms), some considerations are important:

• Feed consumed is not feed disappeared: Due to differences in feeder design and feeder adjustment, these two values can differ by 10-30 %. If FCR is calculated for economic purposes, the wasted feed must be included, as it causes costs and must be paid by the farmer. However, if FCR is calculated for scientific purposes (e.g., a performance trial), only the feed consumed should be included.
• Even if they are same-aged animals, individuals or groups differ in weight. Hence, they have different requirements for maintenance and also diverging quantity left for production. To avoid mistakes, weight-corrected FCR can be used.
• Nutrient utilization also depends on genotype and sex; thus, comparisons should consider these factors as they also influence weight gain and body composition (Patience et al., 2015).

Many factors influence the FCR

There are internal and external factors that influence feed efficiency. Internal factors originate in the animal and include genetics, age, body composition, and health status. In contrast, external factors include feed composition, processing, and quality, as well as the environment, welfare enrichment, and social aspects.

1. Species

Different species have different body sizes and physiology and, therefore, vary in their growth and maintenance requirements, impacting their efficiency in converting the feed.

Table 1: FCRs of different species

Compared to terrestrial animals, for example, fish and other aquatic animals have a low FCR. Being poikilothermic (animals whose body temperature ranges widely), they don’t spend energy on maintaining their body temperature if the surrounding water is within their optimal range. As they are physically supported by water, they also need less energy to work against gravity. Furthermore, carnivorous fish are offered highly digestible, nutrient-dense feed, which lowers their requirements in quantity. Omnivorous fish, on the other hand, also consume feedstuffs not provided by the producer (e.g., algae and krill), which is not considered in the calculation. Broilers are the only farm animals achieving a similar FCR.

2. Sex, age, and growth phase

Sex determines gene expression related to the regulation of feed intake and nutrient utilization. Males have a better feed conversion and put on more lean meat than females and castrates, which grow slower and easier run to fat.

Young animals have a fast growth rate and are offered nutritionally dense feed; hence, their FCR is lower. When the animal grows and gains weight, its energy requirement for maintenance increases and its growth rate and the feed nutrient density diminish.

Table 2: FCR during different life phases of pigs (based on Adam and Bütfering, 2009)

3. Health and gut health

Health decisively impacts feed conversion. An animal that is challenged by pathogens reduces its feed intake and, thus, decreases growth. Additionally, the body needs energy for the immune defense, the replacement of damaged or lost tissue, and heat production, in case of fever. As many immune components are rich in protein, this is the first nutrient to become limited.

An imbalance in the gut microbiome also impacts feed conversion: pathogenic microorganisms damage tissues, impair nutrient digestion and absorption, and their metabolic products are harmful. Furthermore, pathogens consume nutrients intended for the host and continue to proliferate at its expense.

4. Environment

The environment influences the way the animals spend their maintenance energy. According to Patience (2012), when a 70 kg pig is offered feed ad libitum, 34 % of the daily energy is used for maintenance. For each °C below the thermoneutral zone, an additional 1.5% of feed is needed for maintenance. In heat stress, each °C above the optimum range decreases feed intake by 2%. Therefore, the feed needs to be denser to fulfill the requirement, or the animal will lose weight. Social stress also influences animal performance, especially chronic stress situations. Keeping the animals in their thermoneutral zone and mitigating the impact of stressors means more energy can go towards performance.

5. Feed quantity, composition, and quality

The feed is the source of nutrients animals convert into production. So, it’s natural that its quality and composition, and the availability of nutrients affect feed efficiency.

Better FCR by increasing nutrient density and digestibility

Higher energy content in the diet and better protein digestibility improve FCR. Saldaña et al. (2015) assert that increasing the energy content of a diet led to a linear decrease of the average daily feed intake but improved FCR quadratically. The energy intake by itself remained equal. However, these diet improvements also increase costs, and a cost-benefit analysis should be conducted.

Feed form and particle size play an important role

Feed processing can improve nutrient utilization. Particle size, moisture content, and whether the feed is offered as pellets or mash influence feed efficiency. Reducing the particle size leads to a higher contact surface for digestive enzymes and higher digestibility. Chewning et al. (2012) tested the effect of particle size and feed form on FCR in broilers. They found that pellet diets enable better FCRs than mash diets – one reason is the lower feed waste, another one the smaller feed particle size in the pelleted feed. Comparing the different tested mash diets, the birds receiving feed with a particle size of 300 µm performed better than the birds getting a diet with 600 µm particles.

Richert and DeRouchey (2015) show that pigs’ feed efficiency improved by 1.3 % for every 100 µm when the particle size was reduced from 1000 µm to 400 µm , as the contact surface for the digestible enzymes increased. In weaning piglets of 28-42 days, the increase of particle size from 394 µm to 695 µm worsened FCR from 1.213 to 1.245 (Almeida et al., 2020). There is a flipside to smaller particle size as well, however: high quantities of fines in the diet can lead to stomach ulceration in pigs (Vukmirović et al., 2021).

Non-starch polysaccharide (NSP)-rich cereals worsen FCR

The carbohydrates in feedstuffs such as wheat, rye, and barley are not only energy suppliers, and if not managed well, the inclusion of these raw materials can deteriorate feed conversion. Vegetable structural substances such as cellulose, hemicellulose, or lignin (e.g., in bran), are difficult or even impossible to utilize as they lack the necessary enzymes.

Figure 1: Contents of arabinoxylan and ß-glucan in grain (according to Bach Knudsen, 1997)

Additionally, water-soluble NSPs (e.g., pectins, but also ß-glucans and pentosans) have a high water absorption capacity. These gel-forming properties increase the viscosity of the digesta. High viscosity reduces the passage rate and makes it more difficult for digestive enzymes and bile acids to come into contact with the feed components. Also, nutrients’ contact with the resorptive surface is reduced.

Another disadvantage of NSPs is their “cage effect.” The water-insoluble NSPs cellulose and hemicellulose trap nutrients such as proteins and digestible carbohydrates. Consequently, again, digestive enzymes cannot reach them, and they are not available to the organism.

Molds and mycotoxins impair feed quality, but also animal health

Molds reduce the nutrient and energy content of the feed and negatively impact feed efficiency. They are dependent on active water in the feed and feed ingredients. Compared to bacteria, which need about 0.9-0.97 Aw (active water), most molds require only 0.86 Aw.

Table 3: Comparison of 28-day-old chicks performance fed not-infested and molded corn

Besides spoiling raw materials and feed and reducing their nutritional value, molds also produce mycotoxins which negatively impact animal health, including gut health. They damage the intestinal villi and tight junctions, reducing the surface for nutrient absorption. In a trial with broiler chickens, Kolawole et al. (2020) showed a strong positive correlation between the FCR and the exposure to different mycotoxins. The increase in levels of toxin mixtures resulted in poor FCR. Williams and Blaney (1994) found similar results with growing pigs. The animals received diets containing 50 % and 75 % of corn with 11.5 mg nivalenol and 3 mg zearalenone per kg. The inclusion of contaminated corn led to a deterioration of feed efficiency from 2.45 (control) to 3.49 and 3.23.

Oxidation of fats also affects feed quality

DDGS (distiller’s dried grains with solubles), by-products of corn distillation processes, are often used as animal feed, especially for pigs. The starch content is depleted in the distillation process and thus removed. The fat, however, is concentrated, and DDGS reach a similar energy content as corn.

Pigs also receive fats from different sources (e.g., soybean or corn oil, restaurant grease, animal-vegetable blends), especially in summer. Due to heat, the animals eat less, so increasing energy density in the feed is a possibility to maintain the energy intake.  The high fat content, however, makes these feeds susceptible to oxidation at high temperatures.

The oxidation of feedstuffs manifests in the rancidity of fats, destruction of the fat-soluble vitamins A, D, and E, carotenoids (pigments), and amino acids, leading to a lower nutritional value of the feed.

Use adequate supplements to enhance FCR

The feed industry offers many solutions to improve the FCR for different species. They usually target the animal’s digestive health or maintain/enhance feed quality, including increasing nutrient availability.

1. Boost your animals’ gut health

Producers can improve gut health by preventing the overgrowth of harmful microorganisms and by mitigating the effects of harmful substances. For this purpose, two kinds of feed additives are particularly suitable: phytomolecules and products mitigating the impact of toxins and mycotoxins.

Phytomolecules help stabilize the balance of the microbiome

By preventing the proliferation of pathogens, phytomolecules help the animal in three ways:

1. They prevent pathogens from damaging the gut wall
2. They deter and mitigate inflammation
3. By inhibiting the overgrowth of pathogens, they promote better nutrient utilization by the animal

Only a healthy gut can optimally digest feed and absorb nutrients.

In trials testing the phytogenic Activo product range, supplemented animals showed the following FCR improvements compared to non-supplemented control groups (Figure 2).  Note that phy­tomolecules also have a digestive effect that contributes to the FCR improvements:

Figure 2: FCR improvements for animals receiving Activo

Products mitigating the adverse effects of toxins

Both mycotoxins and bacterial toxins negatively impact gut health. Mycotoxins are ingested with the feed; bacterial toxins appear when certain bacteria proliferate in the gut, e.g., gram-negative bacteria releasing LPS or Clostridium perfringens producing NetB and Alpha-toxin.

Products that mitigate the harmful effects of toxins help to protect gut health and maintain an optimal feed efficiency, as shown with a trial conducted with Mastersorb Gold:

Table 4: Trial design, the impact of Mastersorb Gold on broilers challenged with zearalenone and DON-contaminated feed

Figure 3: Average FCR for broilers, with or without zearalenone and DON challenge, with or without Mastersorb Gold supplementation

2. Improve nutrient utilization

Maximum use of the nutrients contained in the feed can be obtained with the help of feed additives that promote digestion. Targeting the animal, selected phytomolecules are used for their digestive properties. Focusing on the feed, specific enzymes can unlock nutrients and thus improve feed efficiency.

Phytomolecules support the animal’s digestive system

Phytomolecules promote optimal digestion and absorption of nutrients by stimulating the secretion of digestive juices, such as saliva or bile, enhancing enzyme activity, and favoring good GIT motility (Platel and Srinivasan, 2004). FCR improvements thanks to the use of a phy­tomolecules-based product (Activo) are shown in figure 2.

Enzymes release more nutrients from feed

Enzymes can degrade arabinoxylans, for example. Arabinoxylans are the most common NSP fraction in all cereals – and are undigestible for monogastric animals. Enzymes can make these substances available for animals, allowing for complete nutrient utilization.  Additionally, nutrients trapped due to the cage effect are released, altogether increasing the energy content of the diet and improving FCR.

3. Be proactive about preserving feed quality

The quality of feed can deteriorate, for instance, when nutrients oxidize, or mold infestation occurs. Oxidation by-products promote oxidative stress in the intestine and may lead to tissue damage. Molds, in turn, take advantage of the nutrients contained in the feed and produce mycotoxins. Both cases illustrate the importance of preventing feed quality issues. Feed additives such as antioxidants and mold inhibitors mitigate these risks.

Antioxidants prevent feed oxidation

Antioxidants scavenge free radicals and protect the feed from spoilage. In animals, they mitigate the adverse effects of oxidative stress. Antioxidants in pig nutrition can stabilize DDGS and other fatty ingredients in the feed, maintaining nutrient integrity and availability. Figure 4 shows the FCR improvement that a producer in the US obtained when using the antioxidant product Santoquin in pork finisher diets containing 30% DDGS.

Figure 4: FCR improvement in pigs receiving Santoquin (trial with a Midwest pork producer)

In DDGS-free diets, which are more common in poultry production, antioxidants also help optimize FCR, as shown by the results of a comprehensive broiler field study in 2015 (figure 5).

Figure 5: FCR in broilers receiving Santoquin, compared to a non-supplemented control group

Inhibiting molds and keeping feed moisture

To round off the topic of feed quality preservation, one should consider mold inhibitors, which also play an essential role. Used at the feed mill, these products blend two types of ingredients with their different modes of action: surfactants and organic acids. Surfactants bind active water so that the moisture of the feed persists, but fungi cannot survive. Organic acids, on the other hand, have anti-fungal properties, directly acting against molds. Both actions together prevent the reduction of energy in the feed, keeping feed efficiency at optimal levels.

Conclusion

The improvement of feed efficiency ranks as one of the most, if not the most, critical measures to cope with rising feed costs. By achieving optimal nutrient utilization, producers can make the most out of the available raw materials.

The feed industry offers diverse solutions to support animal producers in optimizing feed efficiency. Improving gut health, mitigating the negative impact of harmful substances, and maintaining feed quality are crucial steps to achieving the best possible FCR and, hence, cost-effective animal production.

References

Adam, F., and L. Bütfering. “Wann Müssen Meine Schweine an Den Haken?” top agrar. top agrar online, October 1, 2009. https://www.topagrar.com/schwein/aus-dem-heft/wann-muessen-meineschweine-an-den-haken-9685161.html.

Almeida, Leopoldo Malcorra, Vitor Augusto Zavelinski, Katiucia Cristine Sonálio, Kariny Fonseca da Silva, Keysuke Muramatsu, and Alex Maiorka. “Effect of Feed Particle Size in Pelleted Diets on Growth Performance and Digestibility of Weaning Piglets.” Livestock Science 244 (2021). https://doi.org/10.1016/j.livsci.2020.104364.

Chewning, C.G., C.R. Stark, and J. Brake. “Effects of Particle Size and Feed Form on Broiler Performance.” Journal of Applied Poultry Research 21, no. 4 (2012): 830–37. https://doi.org/10.3382/japr.2012-00553.

Gaines, A. M., B. A. Peerson, and O. F. Mendoza. “Herd Management Factors That Influence Whole Feed Efficiency.” Essay. In Feed Efficiency in Swine, edited by J. Patience, 15–39. Wageningen Academic, 2012.

Kolawole, Oluwatobi, Abigail Graham, Caroline Donaldson, Bronagh Owens, Wilfred A. Abia, Julie Meneely, Michael J. Alcorn, Lisa Connolly, and Christopher T. Elliott. “Low Doses of Mycotoxin Mixtures below EU Regulatory Limits Can Negatively Affect the Performance of Broiler Chickens: A Longitudinal Study.” Toxins 12, no. 7 (2020): 433. https://doi.org/10.3390/toxins12070433.

Patience, J. F. “The Influence of Dietary Energy on Feed Efficiency in Grow-Finish Swine.” Essay. In In Feed Efficiency in Swine, edited by J. Patience, 15–39. Wageningen Academic, 2012.

Patience, John F., Mariana C. Rossoni-Serão, and Néstor A. Gutiérrez. “A Review of Feed Efficiency in Swine: Biology and Application.” Journal of Animal Science and Biotechnology 6, no. 1 (2015). https://doi.org/10.1186/s40104-015-0031-2.

Platel, K., and K. Srinivasan. “Digestive Stimulant Action of Spices: A Myth or Reality?” Indian J Med Res, pp 167-179 119 (May 2004): 167–79. http://www.ncbi.nlm.nih.gov/pubmed/15218978

Richert, B. T., and J. M. DeRouchey. “Swine Feed Processing and Manufacturing.” Pork Information Gateway, September 14, 2015. https://porkgateway.org/resource/swine-feed-processing-and-manufacturing/.

Saldaña, B., P. Guzmán, L. Cámara, J. García, and G.G. Mateos. “Feed Form and Energy Concentration of the Diet Affect Growth Performance and Digestive Tract Traits of Brown-Egg Laying Pullets from Hatching to 17 Weeks of Age.” Poultry Science 94, no. 8 (2015): 1879–93. https://doi.org/10.3382/ps/pev145.

Vukmirović, Đuro, Radmilo Čolović, Slađana Rakita, Tea Brlek, Olivera Đuragić, and David Solà-Oriol. “Importance of Feed Structure (Particle Size) and Feed Form (Mash vs. Pellets) in Pig Nutrition – A Review.” Animal Feed Science and Technology 233 (2017): 133–44. https://doi.org/10.1016/j.anifeedsci.2017.06.016.

By Han Zhanqiang, Poultry Technical Manager, EWN China

Poultry meat accounts for more than one-third of global meat production. With increasing demand levels, the industry faces several challenges. Among them is the continuous supply of day-old chicks, which is affected by various issues. Mitigation strategies should be taken to ensure the supply of good quality day-old chicks to production farms.

Fast-growing broilers versus fit breeders

The poultry industry is challenged by the broiler-breeder paradox: on the one hand, fast-growing broilers are desirable for meat production. On the other hand, the parents of these broilers have the same genetic traits, but in order to be fit for reproduction, their body weight should be controlled. Thus, feed restriction programs, considering breeder nutritional requirements, are necessary to achieve breed standards for weight, uniformity, body structure, and reproductive system development, determining the success of day-old chick production.

Mycotoxins affect breeder productivity

During the rearing period, gut health problems such as coccidiosis, necrotic enteritis, and dysbiosis affect flocks. Also during the laying period, breeder flocks are also susceptible to disturbances in gut health, especially during stressful periods, leading to reduced egg production and an increase in off-spec eggs. One measure to restrain these challenges is the strict quality control of the feed. In this context, contamination with mycotoxins is an important topic. However, due to the nature of fungal contamination and limitations of sampling procedures, mycotoxins may not be detected or may be present at levels considered low and not risky.

Existing studies on mycotoxins in breeders indicate that mycotoxins can cause varying degrees of reduction in egg production and hatchability and are also associated with increased embryonic mortality. Recent studies have shown that low levels of mycotoxins interact with other stressors and may lead to reduced productivity. These losses are often mistaken for normal breeder lot variation. However, they cause economic losses far greater than normal flock-to-flock variability.

Mycotoxins impair the functionality of the gut

Low mycotoxin levels affect gut health. Individually and in combinations, mycotoxins such as DON, FUM, and T2 can impact gut functions such as digestion, absorption, permeability, immunity, and microbial balance. This is critical in feed-restricted flocks because it decreases body weight and uniformity, and in laying animals, egg production and egg quality can be reduced. Absorption of calcium and vitamin D3, which are critical for eggshell formation, depends on gut integrity and the efficiency of digestion and absorption. These factors can be adversely affected by even low mycotoxin levels: eggshells can become thin and brittle, thereby reducing hatching eggs and increasing early embryo mortality.

Prevention is the key to success in day-old chick production, therefore:

• avoid the use of raw materials with known mycotoxin contamination.
• use feed additives prophylactically, especially with anti-mycotoxin and antioxidant properties.

Prevention is an alternative approach to assure health and productivity in -many times unknown- mycotoxin challenges.

Figure 1: Effect of mycotoxins on eggshell quality and embryo death (Caballero, 2020)

University trial shows anti-mycotoxin product improving performance

A recent study by the University of Zagreb confirmed that long-term (13 weeks) exposure to feed contaminated with mycotoxins has an impact on egg production performance – a challenge that could be counteracted by using an anti-mycotoxin product.

The negative control (NC) was offered feed without mycotoxins. In contrast, the challenged control (CC), as well as a third group, received feed contaminated with 200ppb of T2, 100ppb of DON, and 2500ppb of FMB1. To the feed of the third group, an anti-mycotoxin feed additive (Mastersorb Gold, EW Nutrition) was given on top (CC+MG).

Figure 2: Influence of mycotoxins on feed intake and the effect of the anti-mycotoxin product Mastersorb Gold

Figure 3: The effect of mycotoxins on the cumulative number of eggs and the compensating effect of Mastersorb Gold

Figure 4: The impact of mycotoxins on the cumulative egg mass and the countereffect of Mastersorb Gold

As expected, the contaminated feed reduced feed intake, egg production, and egg weight (Fig. 2-4). Moreover, the liver and gut were affected which was evidenced in histopathological lesion scores of the organs: the control group had the lowest score, followed by the group fed Mastersorb Gold. The challenged group without any anti-mycotoxin product scored the highest.

Breeders are susceptible to mycotoxins and need our support

Broiler breeders and day-old chick production can be affected by long-term exposure to mycotoxins, which often exceeds the tolerance range of average flocks. To reduce or even prevent the potential impact of mycotoxins, a comprehensive management strategy is crucial. This includes responsible raw material procurement, storage, and feed processing leading to high feed quality, and the consideration of breeders’ nutrient demands. The inclusion of highly effective products to manage mycotoxin risk is an additional tool to maintain breeder performance.

By Dr. Ajay Bhoyar, Global Technical Manager – Poultry, EW Nutrition

Rancidity testing is essential in the feed industry, as a key indicator of product quality and shelf life. It is conducted to determine the level of oxidation in samples of feed or feed ingredients and it can be performed through a number of analytical methods.

Rancidity is the process by which fats and oils in food become degraded, resulting into off-odor/flavor, taste, and texture. This process is caused by the oxidation of unsaturated fatty acids and can be accelerated by factors such as exposure to light, heat, and air. Rancidity can occur naturally over time, but it can also be accelerated by improper storage or processing of animal products. Fats are highly susceptible to degradation due to their chemical nature.

How does oxidative rancidity occur?

Oxidation occurs when an oxygen ion replaces a hydrogen ion within a fatty acid molecule and higher numbers of double bonds within the fatty acid increase the possibility of autoxidation. Oxidative rancidity results from the breakdown of unsaturated fatty acids in the presence of oxygen. Light and heat promote this reaction, which results in the generation of aldehydes and ketones – compounds which impart off-odors and flavors to food products. Pork and chicken fat demonstrate a higher degree of unsaturated fatty acids compared with beef fat and are therefore more prone for rancidity.

Oxidation: a three-step process

Fat/oil oxidation is a three-step process (Initiation, Propagation and Termination). Therefore, the oxidation products depend on the time. In the first phase, called Initiation, the formation of free radicals begins and accelerates.

Once the initial radicals have formed, the formation of other radicals proceeds rapidly in this second phase called Propagation. In this part of the process, a chain reaction of high energy molecules, which are variations of free radicals and oxygen, are formed and can react with other fatty acids. These reactions can proceed exponentially, if not controlled. Also in this phase, the rate of peroxide radical formation will reach equilibrium with the rate of decomposition to form a bell-shaped curve.

In the final phase, called Termination, the starting material has been consumed, and the peroxide radicals, as well as other radicals decompose into secondary oxidation by-products such as esters, short chain fatty acids, polymers, alcohols, ketones and aldehydes. It is these secondary oxidation by-products, which can negatively affect the growth and performance of animals.

Fig. 1: Oxidation: a three-phase series of reactions

Antioxidants preserve the quality of rendered products

Chemical antioxidants are used in the rendering industry to help preserve the quality of animal by-products. Synthetic antioxidants, such as BHA, BHT, and ethoxyquin, can help prevent the oxidation of these by-products, which can cause them to become rancid. These chemical antioxidants are added in small amounts to the raw materials prior to rendering or can be incorporated into the finished products to help extend their shelf life and maintain their nutritional value. It is important to note that the use of antioxidants in the rendering industry must be done in compliance with regulations and guidelines set forth by the FDA and other governing bodies.

Natural antioxidants like tocopherols, rosemary extract, ascorbyl palmitate, etc. are also used to prevent oxidation and maintain the freshness of rendered products, if the chemical antioxidants cannot be used.

Rancidity testing

Rancidity testing is the process of determining the level of rancidity in a product. Testing for level of rancidity is used widely as an indication of product quality and stability.

There are several methods used for rancidity testing, including:

Organoleptic rancidity testing

Oxidation of fats and oils leads to a change in taste, smell, and appearance. Organoleptic testing involves using the senses (sight, smell, taste) to determine the level of rancidity. Trained testers will examine the product for visual signs of spoilage, such as discoloration or the presence of crystals, and will also smell and taste the product to detect any off-flavors or odors.

Chemical & instrumental rancidity testing

Chemical testing involves using chemical methods to measure the level of rancidity. One common method is the peroxide value test, which measures the amount of peroxides (indicators of rancidity) in the product. Another method is the p-anisidine test, which measures the level of aldehydes (another indicator of rancidity) in the product.

Peroxide value

Peroxide Value (PV) testing determines the amount of peroxides in the lipid portion of a sample through an iodine titration reaction targeting peroxide formations. Peroxides are the initial indicators of lipid oxidation and react further to produce secondary products such as aldehydes. Because peroxide formation increases rapidly during the early stages of rancidification but subsequently diminishes over time, it is best to pair PV testing with p-Anisidine Value to obtain a fuller picture of product quality.

Fig.2: Oxidation products changes with time

p-Anisidine (p-AV)

p-AV is a determination of the amount of reactive aldehydes and ketones in the lipid portion of a sample. Both compounds can produce strong objectionable flavors and odors at relatively low levels. The compound used for this analysis (p-Anisidine) reacts readily with aldehydes and ketones and the reaction product can be measured using a colorimeter. Samples that are particularly dark may not be the most applicable for this analysis as the colorimeter may not be able to adequately measure the wavelength required.

TBARS

Thiobarbituric acid reactive substances (TBARS) are a byproduct of lipid peroxidation (i.e. as degradation products of fats). This can be detected by the TBARS assay using thiobarbituric acid as a reagent. TBA Rancidity (TBAR) also measures aldehydes (primarily malondialdehyde) created during the oxidation of lipids. This analysis is primarily useful for low-fat samples, as the whole sample can be analyzed rather than just the extracted lipids.

The Instrumental testing involves using instruments to measure the level of rancidity.

Gas chromatography

One common method is the use of a gas chromatograph, which can detect the presence of volatile compounds that indicate rancidity.

Fourier-transform infrared spectrophotometer (FTIR)

FTIR method can detect changes in the chemical makeup of the product that indicate rancidity.

Free Fatty Acids (FFA)

FFA testing determines the fatty acids that have been liberated from their triglyceride structure. A titration is performed on the extracted fat from a specific sample. The FFA content is then determined through a calculation of the amount of titrant used to reach the final result. Knowing what type of fat or fat containing product is being tested is important for this analysis to ensure that the appropriate calculation is applied. As the test does not differentiate between fatty acid types, samples with high palmitic or lauric fatty acid composition should have a different calculation factor applied so as to accurately represent the free fatty acid result.

Oxidative Stability Index (OSI)

OSI indicates how resistant a sample is to oxidation. Samples are subjected to heat while air is injected – a process which accelerates oxidation reactions. The samples are monitored, and the time required for the sample to reach an inflection point is determined. This test is useful when testing the efficacy of an antioxidant added to a product. Antioxidants should inhibit free radical propagation and thus increase a samples ability to hold up under the stressing conditions imposed by the OSI analysis. The measuring instrument, the Rancimat.

Analytical testing considerations in rendering operations

It is common to perform regular analytical testing in a rendering operation as a part of quality control and quality assurance program. There are several methods for testing rancidity in rendering operations. It is important to choose the appropriate method based on the type of product and the desired level of accuracy.

The results of rancidity testing are used to monitor and control the rendering process to prevent or minimize rancidity. This may involve adjusting processing conditions, using antioxidants, or implementing other measures to reduce oxidation.

Table. 1: Analytical testing considerations for rendering

Conclusion

Rancidity is a common problem in rendered animal products. It can have detrimental effects on both the quality and safety of the product. It is caused by the oxidation of fats and oils, leading to the formation of harmful compounds such as free radicals and hydroperoxides. The best way to prevent rancidity is through proper storage, packaging, and handling techniques, as well as the use of antioxidants to slow down the oxidation process. It is important for manufacturers and consumers to be aware of the potential for rancidity in rendered animal products and take the necessary precautions to ensure the safety and quality of the product. 

By Predrag Persak, Regional Technical Manager, EW Nutrition

In light of sustainability requirements, shortage of feed materials, and constant pressure on energy efficiency, we must rethink how we deal with all elements that impact our production. Shrinkage is one of the essential impacting elements.  

What is Shrinkage? 

In simple terms, shrinkage is the weight loss in feed or feed materials during receiving, processing, or storage. Shrinkage happens on the farm level but also in feed mills. In this article, we will focus on the latter one. Points or reasons why this happens are diverse but not unknown. Wastages, dust, pests, moisture loss, and scale deviations are some of the most important. Through time, we found efficient ways to close the doors to feather and fur pests that were stealing valuable resources and causing shrinkage. We are also good at weight control when receiving and dispatching, by thoroughly balancing the scales. But one point related to the core of feed production – and the most significant loss – is still left untackled. That is moisture loss through grinding. 

Figure 1: Points of moisture loss and addition in the feed mill 

Grinding is one central point of shrinkage

Grinding and subsequent particle size reduction is essential from many points (handling, nutritional, processing, mixing uniformity, …) and is unavoidable if we want to produce excellent feed. In the case of grinding with hammer mills, we use kinetic energy to make the hammers beat kernels to the desired size. This is a very efficient process. However, during that process, a part of kinetic energy is also transferred to thermal, increasing the temperature of the processed feed materials and resulting in the loss of one part of valuable moisture. Also, due to size reduction and enlargement of the surface, there is much more place for evaporation and moisture movement. Losses can be up to 2%. One essential parameter for high pellet quality is the particle size, but very fine grinding will result in higher shrinkage through moisture and dust losses.

Moisture is decisive  ̶  we must manage it!

The valuable moisture is needed for many reasons. One is weight. Another reason is that nutritional density for feed materials is calculated considering a certain moisture content. Additionally, moisture influences the processing parameters during the pelleting process (targeted moisture content in the conditioner should be 16-18%). Since moisture loss is unavoidable and represents the most significant part of loss or shrinkage, we must manage it. For this purpose, we must substitute lost moisture with added moisture. And in that process, we have a short time to do it properly. Usually, we don´t have enough time for so-called “soaking”. However, with the help of surfactants, the process can be speeded up.

Surf-Ace helps to keep the moisture in the feed

Surf-Ace, a liquid preservative premix for moisture optimization, which contains organic acids / organic acid salts, emulsifiers, and surfactants, helps to keep the moisture in the feed. Conditioning can be hindered by surface tension because water forms a film on the surface of the feed particles, or oil covers the particles. Surf-Ace improves water penetration and retention by decreasing surface tension. Trials show the moisture-optimizing effect of Surf-Ace.

A trial conducted in Jordan demonstrated an increase in moisture in different processing phases (feeder, heater, and the final product). It also showed better maintenance of water in the product during storage (Fig. 2).

Figure 2: Surf-Ace achieved higher moisture levels in different phases of the feed production process

Two further trials conducted in Poland and Serbia also showed that feed millers could increase moisture in the final feed by using Surf-Ace (Fig. 3).

Figure 3: Surf-Ace provided for higher moisture content in the feed

Effective surfactants minimize shrinkage in feed

Shrinkage in times of increasing costs must be minimized by all means. The feed industry offers surfactants that keep the moisture in the feed during processing and prevent at least this part of shrinkage.

Besides the financial aspect, the optimal moisture content in feed and feed materials is important to provide high feed quality, whether concerning pellet quality or percentage of nutrients. Using surfactants, therefore, not only increases profitability but also does its bit concerning sustainability.

By Dr. Ajay Awati, Global Category Manager for Gut Health and Nutrition, EW Nutrition, and Dr. Howard Simmins, InSci Associates

After 30 years of stagnating solutions, in-feed xylanase innovation has finally arrived – with a complete focus on the needs of the broiler feed industry.

It has been over 30 years since xylanase was first introduced in broiler diets in Europe. In the meantime, it has been widely used worldwide with few, if any, major improvements. While the animal feed industry evolved in terms of production landscape, feed processing technologies and use of various by-products, xylanase enzyme technology did not keep pace. In fact, it did not evolve to meet customers’ changing needs and provide that much-needed flexibility of diet formulation for a commercial nutritionist. The wait is over: new in-feed xylanase technology is about to revolutionize broiler nutrition.

Why we need innovative xylanase enzymes for broiler production

Initially, in the 1980s, xylanase was leveraged from industries unrelated to animal production into the feed business. Gut viscosity had been a continuing problem in broiler chickens fed wheat-based diets. It led to an increased risk of enteric disease, generally reducing performance. Xylanase was shown to reduce gut viscosity in wheat-based feed by breaking down soluble arabinoxylans.

As a result, the birds grew as well as if they were fed a low-viscosity corn/soya diet. An additional benefit was lower disease risks from the reduced level of anti-nutritional factors (ANFs) and the multiple negative effects of viscosity in the intestine.

In addition to reducing viscosity, xylanase augments the release in the small intestine of nutrients from previously undigested feedstuffs. The outcome has been the use of an energy matrix value for xylanase, which essentially helps diets through least-cost formulation.

These effects account for the growth of xylanase use in the monogastric feed market. Today, the penetration is above 50%.

Limitations of existing xylanase solutions

Leveraging xylanases from other industries for viscosity reduction in poultry comes with a couple of distinct limitations:

1. Most broiler diets around the globe are based on a corn-soybean formulation, which contains far higher levels of insoluble arabinoxylans than soluble arabinoxylans. In such cases, viscosity is a relatively minor issue compared to the anti-nutritional effect of insoluble arabinoxylans.
2. The reduction of gut viscosity is less relevant in other poultry sectors, such as laying hens and turkeys.

Commercial xylanases would be required to break down insoluble NSPs in which substrate activity may be limited and difficult to predict. Fiber constituents of different cereal grains used in feed are highly variable. By- and co-products derived from cereals contain even more complex fiber components, altered further by the manner of processing that the raw material has undergone.

Additionally, poultry response is highly variable:  For an individual bird, the effectiveness of xylanase depends on the enzyme’s interaction with feed in the gastrointestinal tract (GIT) of the animal, which varies depending on the species and the animal’s age. This may explain why xylanase penetration on the feed market is not as high as that of phytase.

GH10: the next-level xylanase for feed application

A xylanase for feed is required to provide multiple functionalities, of which four are essential:

1. Capacity to break down soluble and insoluble arabinoxylan across a range of typical feedstuffs
2. Rapid activity at optimal pH in the preferred section of the GIT
3. No inhibition in the presence of xylanase inhibitors
4. Comprehensive feed processing thermostability

The GH11 family of xylanases commonly used in feed does not offer these aggregated benefits. They successfully reduce soluble NSPs in wheat-based diets, hence lowering the viscosity level in the broiler GIT. However, they are less effective in the presence of insoluble NSPs in which the arabinoxylan backbone is more complex.

Why GH10 instead of GH11?

The explanation for this can be found in the 3-dimensional structure of the GH11 xylanase. The activity of GH11 xylanases requires 3 or 4 consecutive unsubstituted xylan monomers on the backbone to find an active site. That is why they are hindered by the presence of branches, or side chains, on arabinose backbones. Consequently, they are highly specific, favoring the particularly low-branching wheat backbone.

Xylanases from the GH10 family are entirely different. Although well known, they have not been used in feed yet. The GH10 xylanases require two or fewer consecutive unsubstituted xylan monomers on the backbone to find an active site. Therefore, they can act on xylose residues near branches. This results in both more and shorter xylo-oligomers than found with GH11 xylanases. In simple terms, the GH10 xylanases have a less deep cleft than the GH11 xylanases, providing greater catalytic versatility (Pollet 2010).

Significantly, this potentially allows a broader range of feedstuffs to be incorporated into the complete diet, including co- and by-products, while maintaining performance. Therefore, with GH10, higher levels of cheaper ingredients may be included, with a significant value proposition of further reducing feed costs.

GH10 xylanases generate a range of important prebiotics

As early as 1995, it was proposed that xylanase may affect microbial activity in the gastrointestinal tract through the provision of fermentable oligosaccharides and low molecular weight polysaccharides. These are produced from the hydrolysis of soluble and insoluble arabinoxylans in cereals.

A development of particular interest is that the GH10 xylanases break down the backbone of different fibre components into small xylooligosaccharides (XOS) and arabino-xylanoligosaccharides (AXOS). This action, research shows, has value in supporting the selective growth of fibre-degrading bacteria in the large intestine, conferring positive effects on the host’s health.

The most well-known probiotic strains belong to bifidobacteria and lactobacilli, which have quite different XOS and AXOS utilization systems. Bifidobacterium adolescentis has been shown to consume AXOS and XOS, whereas Lactobacillus brevis utilises only XOS. The outcome is that AXOS releases butyrate, the short-chain fatty acid, which can improve the host’s gut barrier function, as well as reduce Salmonella colonization in broilers. Alongside these health benefits, their presence may improve performance also by reducing FCR. (Courtin et al. 2008; Ribeiro et al. 2018)

As mentioned earlier, the GH10 xylanase requires only two consecutive unsubstituted xylan monomers to cleave the xylan main chain, whereas a GH11 xylanase requires 3 or 4 consecutive unsubstituted xylan monomers. Therefore, the number of potential AXOS and XOS oligomers is higher from the action of the GH10 xylanase. This results in a wider size range of oligomers. The range is valuable as the effect is spread across the large intestine, each oligomer having a different fermentation rate. Consequently, the large intestine’s microbial activity becomes saccharolytic, which potentially reduces the undesirable products of proteolytic degradation, such as phenols and cresols.

Prebiotic combinations will vary depending on the substrate available. However, there is more flexibility in breaking down insoluble NSPs across different feedstuffs using GH10 xylanase compared to GH-11 xylanase.

The future of xylanase: Reducing feed costs through flexible formulation

EW Nutrition’s GH10-based AXXESS XY xylanase, specifically developed for animal feed, has a wide-ranging activity across typical substrates, both in corn-soy and wheat-soy diets. It also allows for a greater proportion of cheaper ingredients, enabling increased flexibility in feedstuff choices and resulting in more stable feed pricing. The activity of the GH10 xylanase in producing oligomers from the breakdown of the arabinoxylan backbone also indicates that it can produce a greater number and diversity of valuable prebiotics that sustain the growth of fiber-degrading microbiota. Consequently, the metabolism of the large intestine is shifted from proteolytic to saccharolytic, which supports the animal’s general health.

The combination of these benefits from using this xylanase results in a bird with a balanced digestive system that is more robust in the face of environmental and health challenges, supporting better performance. Furthermore, this novel enzyme solution gives nutritionists a reliable tool to reduce feed costs by being flexible in diet formulation and opportunistic in using raw materials while maintaining consistency in animal performance. Especially in these times of supply problems and raw material price hikes, such advantages are invaluable.

The naturally thermostable AXXESS XY 1000G is the most advanced xylanase yet. It is a GH10 xylanase that delivers what the industry has been asking for: a fiber-degrading enzyme suited for all poultry feed.

References

Courtin, Christophe M, Katrien Swennen, Willem F Broekaert, Quirine Swennen, Johan Buyse, Eddy Decuypere, Christiaan W Michiels, Bart De Ketelaere, and Jan A Delcour. “Effects of Dietary Inclusion of Xylooligo- Saccharides, Arabinoxylooligosaccha- Rides and Soluble Arabinoxylan on the Microbial Composition of Caecal Contents of Chickens.” Journal of the Science of Food and Agriculture 88, no. 14 (2008): 2517–22. https://doi.org/10.1002/jsfa.3373.

Ribeiro, T., V. Cardoso, L.M.A. Ferreira, M.M.S. Lordelo, E. Coelho, A.S.P. Moreira, M.R.M. Domingues, M.A. Coimbra, M.R. Bedford, and C M Fontes. “Xylo-Oligosaccharides Display a Prebiotic Activity When Used to Supplement Wheat or Corn-Based Diets for Broilers.” Poultry Science 97, no. 12 (2018): 4330–41. https://doi.org/10.3382/ps/pey336.

Pollet, Annick. “Functional and Structural Analysis of Glycoside Hydrolase Family 8, 10 and 11 Xylanases with Focus on Bacillus Subtilis Xylanase A,” 2010. https://www.biw.kuleuven.be/m2s/clmt/lmcb/publications/docs/apollet

By Dr. Inge Heinzl, Editor, and Dr. Ruturaj Patil, Global Product Manager – Phytogenics, EW Nutrition 

For millennia, plants have been used for medicinal purposes in human and veterinary medicine and as spices in the kitchen. Since the ban of antibiotic growth promoters in 2006 by the European Union, they also came into focus in animal nutrition. Due to their digestive, antimicrobial, and gut health-promoting characteristics, they seemed an ideal alternative to compensate for the reduced use of antibiotics in critical periods such as brooding, feed change or gut-related stress.

To optimize the benefits of phytomolecules, it is crucial that

• the phytomolecules levels are standardized for consistent results and synergy
• they show the highest stability during stringent feed processing; being often highly volatile substances, they should not get lost at high temperatures and pressure
• the phytomolecules are preferably completely released and available in the animal to achieve the best effectiveness.

First step: Standardized phytomolecules

Essential oils and other phytogenics are sourced from plants. The composition of the plants substantially depends on genetic dissimilarity within accessions, plant origin, the site conditions, such as weather, soil, community, and harvest time, but also sample drying, storage, and extraction processes (Sadeh et al., 2019; Yang et al., 2018; Ehrlinger, 2007). For example, the oil extracted from thyme can contain between 22 and 71 % of the relevant phenol thymol (Soković et al., 2009; Shabnum and Wagay, 2011; Kowalczyk et al., 2020).

Modern technology enables the production of standardized phytomolecules with the highest degree of purity and lowest possible batch-to-batch variation for high-quality products. It also offers increased environmental and economic sustainability due to reliable and cost-effective sourcing technology.

Using such highly standardized phytomolecules enables the production of phytogenic-based feed supplements of consistently high quality.

Second step: Selection of the most suitable phytomolecules

Phytomolecules have different primary characteristics. Some support digestion (Cho et al., 2006, Oetting, 2006; Hernandez, 2004); others act against pathogens (Sienkiewitz et al., 2013; Smith-Palmer et al., 1998; Özer et al., 2007) or are antioxidants (Wei and Shibamoto, 2007; Cuppett and Hall, 1998). To optimize gut health in animal production, one of the main promising mechanisms is reducing pathogens while promoting beneficial microbes. The decrease of pathogens in the gut not only decreases the risk of enteritis incidence but also eliminates the inconvenient competitors for feed.

In order to find out the best combination serving the intended purpose, a high number of different phytomolecules need to be evaluated concerning their structure, chemical properties, and biological activities first. Availability and costs of the substances are further factors to consider. With the selection of the most suitable phytomolecules, different mixtures are produced and tested for their effectiveness. Here, it is essential to concern synergistic or antagonistic effects.

For an effective and efficient blend of phytomolecules, many steps of selection and tests are necessary – and as a result, possibly only a few mixtures can meet the requirements.

Third step: Protecting the ingredients

Many phytomolecules are inherently highly volatile. So, only having a standardized content of phytogenics in the product can not ensure the full availability of phytomolecules when used through animal feed. Some parts of the ingredients might already get lost in the feed mill due to the stringent feed hygienization process followed by feed millers to reduce pathogenic load. The heating is a significant challenge for the highly-volatile components in a phytomolecule-based product. So, protecting these phytomolecules becomes imperative to guarantee that the phytomolecules put into the feed will reach the animal.

A delicate balancing act is required to ensure the availability and activity of phytomolecules at the right site in the gut. The phytomolecules must not get lost during feed processing but must also be released in the intestine. A carrier with capillary binding of the phytomolecules together with a protective coating can be one of the available effective solutions. It protects the ingredients during feed processing, and ensures the release in the animal.

Study shows excellent stability of Ventar D under challenging conditions

Ventar D is a latest generation phytomolecule-based solution for gut health optimization introduced by ​EW Nutrition, GmbH. A scientific study was conducted to compare the stability of Ventar D, in the pelleting process, with two leading phytogenics competitor feed supplements.

For this trial, feed with the different added phytogenic feed supplements had to undergo a conditioning and pelletization process. The active ingredients were analyzed before and after the pelletization process. All phytogenic feed supplements under testing were added to standard broiler feed at the producer’s recommended inclusion rate. The tests took place under conditioning times of 45, 90, and 180 seconds and pelleting temperatures of 70, 80, and 90°C (158, 176, and 194°F). After cooling, triplicate samples were collected and analyzed. The respective marker substance was analyzed through gas chromatography/mass spectrometry (GC/MS) analysis to measure the recovery rate in the finished feed. The phytomolecule content of the mash feed (before pelletization) found by the laboratory was used as a baseline and set to 100% recovery. The recovery rates of the pelleted feed were evaluated relative to this baseline.

The results are presented in figure 1. Ventar D showed the highest stability of active ingredients with recovery rates of 90% at 70°C/45 sec. or 80°C/90 sec and 84% at 90°C/180 sec. The modern production technology used for Ventar D ensures that the active ingredients are well protected throughout the pelletization process.

Figure 1: Phytomolecule stability under processing conditions, relative to mash baseline (100%)

Another trial was conducted in a feed mill in the US. For this trial, ten samples were collected from different batches of mash feed where Ventar D was added at 110g/t. Conditioning of the mash feed was at 87.8°C (190°F) for 6 minutes and 45 seconds. After the pelleting process, ten samples from the pelleted feed were collected from the continuous flow with a 5 min gap between the samplings to determine Ventar D’s recovery.

The average recovery achieved for Ventar D was 92%.

Trials show improved growth performance

Initial trials showed Ventar D’s complete release in digestion models. To examine the benefit in in-vivo conditions, Ventar D was tested in broilers at an inclusion rate of 100 g/MT.

Several in vitro studies proved the antimicrobial activity of Ventar D. One test also confirms that Ventar D could exhibit differential antimicrobial activity by having stronger activity against common enteropathogenic bacteria while sparing the beneficial ones (Heinzl, 2022). Moreover, Ventar D’s antioxidant and anti-inflammatory activity support better gut barrier functioning. Better gut health leads to higher growth performance and improved feed conversion, which could be demonstrated in several trials with broilers (figures 2 and 3). In the tests, a group fed Ventar D was compared to either a control group with no such feed supplement or groups supplied with competitor products at the recommended inclusion rates.

Compared to a negative control group, the Ventar D group consistently showed a higher average daily gain of 0.3-4.1 g (0.5-8.5 %)  and a 3-4 points better feed conversion. Compared to competitor products, Ventar D provided 1-1.7 g (2-3 %) higher average daily gain and a 3 points better /1 point higher FCR than competitors 2 and 1.

Figure 2: Average daily gain (g) – results of several trials conducted with broilers

Figure 3: FCR – results of several trials conducted with broilers

Standardization and new technologies for higher profitability

Several in vitro and in vivo studies proved that Ventar D takes “phytomolecules’ power” to the next level: Combining standardized phytomolecules and optimal active ingredient protection leads to superior product stability during feed processing. The higher amount of active ingredients arriving in the gut improves gut health and increases the production performance of the animals. Ventar D shows how we can use phytomolecules more effectively and benefit from higher farm profitability.

References:

Cho, J. H., Y. J. Chen, B. J. Min, H. J. Kim, O. S. Kwon, K. S. Shon, I. H. Kim, S. J. Kim, and A. Asamer. “Effects of Essential Oils Supplementation on Growth Performance, IGG Concentration and Fecal Noxious Gas Concentration of Weaned Pigs”. Asian-Australasian Journal of Animal Sciences 19, no. 1 (2005): 80–85. https://doi.org/10.5713/ajas.2006.80.

Cuppett, Susan L., and Clifford A. Hall. “Antioxidant Activity of the Labiatae”. Advances in Food and Nutrition Research 42 (1998): 245–71. https://doi.org/10.1016/s1043-4526(08)60097-2.

Ehrlinger, M. “Phytogenic Additives in Animal Nutrition.” Dissertation, Veterinary Faculty of the Ludwig Maximilians University, 2007.

Heinzl, I. “Efficient Microbiome Modulation with Phytomolecules”. EW Nutrition, August 30, 2022. https://ew-nutrition.com/pushing-microbiome-in-right-direction-phytomolecules/.

Hernández, F., J. Madrid, V. García, J. Orengo, and M.D. Megías. “Influence of Two Plant Extracts on Broilers Performance, Digestibility, and Digestive Organ Size.” Poultry Science 83, no. 2 (2004): 169–74. https://doi.org/10.1093/ps/83.2.169.

Kowalczyk, Adam, Martyna Przychodna, Sylwia Sopata, Agnieszka Bodalska, and Izabela Fecka. “Thymol and Thyme Essential Oil—New Insights into Selected Therapeutic Applications.” Molecules 25, no. 18 (2020): 4125. https://doi.org/10.3390/molecules25184125.

Lindner, , U. “Aromatic Plants – Cultivation and Use.” Düsseldorf: Teaching and Research Institute for Horticulture Auweiler-Friesdorf, 1987.

Oetting, Liliana Lotufo, Carlos Eduardo Utiyama, Pedro Agostinho Giani, Urbano dos Ruiz, and Valdomiro Shigueru Miyada. “Efeitos De Extratos Vegetais e Antimicrobianos Sobre a Digestibilidade Aparente, O Desempenho, a Morfometria Dos Órgãos e a Histologia Intestinal De Leitões Recém-Desmamados.” Revista Brasileira de Zootecnia 35, no. 4 (2006): 1389–97. https://doi.org/10.1590/s1516-35982006000500019.

Sadeh, Dganit, Nadav Nitzan, David Chaimovitsh, Alona Shachter, Murad Ghanim, and Nativ Dudai. “Interactive Effects of Genotype, Seasonality and Extraction Method on Chemical Compositions and Yield of Essential Oil from Rosemary (Rosmarinus Officinalis L”.).” Industrial Crops and Products 138 (2019): 111419. https://doi.org/10.1016/j.indcrop.2019.05.068.

Shabnum, Shazia, and Muzafar G. Wagay. “Essential Oil Composition of Thymus Vulgaris L. and Their Uses”. Journal of Research & Development 11 (2011): 83–94.

Sienkiewicz, Monika, Monika Łysakowska, Marta Pastuszka, Wojciech Bienias, and Edward Kowalczyk. “The Potential of Use Basil and Rosemary Essential Oils as Effective Antibacterial Agents.” Molecules 18, no. 8 (2013): 9334–51. https://doi.org/10.3390/molecules18089334.

Smith-Palmer, A., J. Stewart, and L. Fyfe. “Antimicrobial Properties of Plant Essential Oils and Essences against Five Important Food-Borne Pathogens”. Letters in Applied Microbiology 26, no. 2 (1998): 118–22. https://doi.org/10.1046/j.1472-765x.1998.00303.x.

Soković, Marina, Jelena Vukojević, Petar Marin, Dejan Brkić, Vlatka Vajs, and Leo Van Griensven. “Chemical Composition of Essential Oils of Thymus and Mentha Species and Their Antifungal Activities”. Molecules 14, no. 1 (2009): 238–49. https://doi.org/10.3390/molecules14010238.

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By Predrag Persak, Regional Technical Manager Europe, EW Nutrition

Imagine you’re at a pub quiz dedicated to feed production, and this question pops up: name a process that returns up to 25 times what was invested in it. Do you know the answer? I’m pretty sure you are probably using it every day: pelleting. For every unit of used energy, pelleting generates up to 25 times more in terms of the nutritional value for animals (mostly metabolizable energy).

The math is simple: while we gain 200 kcal/kg by pelleting broiler mash feed, only 10 Kilowatts are used to produce one ton of broiler feed. This is just one example of how sustainability is at the core of feed production – and has always been, long before it became a buzzword. So, to all those who operate feed mills, who take care of sourcing and quality, and to those behind numbers that represent nutritional values: You are pioneers of sustainability and should be proud of that.

How feed processing can drive sustainability efforts

Besides being proud, we must also be very responsible. Every nutritionist should focus on

1. how processing of feed materials and feed influences the release of nutrients, nutrient density, and exclusion of antinutrients, and
2. how processing can improve these dimensions, making feed more sustainable.

Do we take processing sufficiently into consideration? Do we create formulations in a dynamic or more static way? Not least in an era of precision feeding, the shift from static to dynamic is inevitable.

This is even clearer when we consider how processing can influence digestion, absorption, and the performance of animals. How so? Feed processing makes previously unusable materials suitable for nutrition or improves already usable materials. So, the feed processing itself is a key to sustainability.

Through processing, we alter the physical, chemical, and edible properties of used feed materials, making them usable for animals. Through proper processing, we improve the digestibility of feed materials by up to 20%, enabling a more effective – and thus more sustainable – use of feed resources. In practice, there is room for improvement to make feed processing even more of a sustainability champion.

Moisture optimization is key to energy-efficient pelleting

Let’s take a closer look at pelleting since it requires the most energy within feed processing. How much energy is used? This depends on many factors and can range from 5 KW/h up to 25. Pelleting is mostly used in broiler diets to reduce nutrient segregation and feed sorting and, by extension, feed wastage. Pelleting has also been found to increase the weight gain of individual birds and flock uniformity, and overall feed efficiency is higher.

Pelleting involves the agglomeration of mixed feed into whole pellets through a mechanical process using heat, moisture, and pressure (Falk, 1985). Heat (energy that is transported through steam) has the largest impact on pelleting efficacy. Steam injected during conditioning increases feed moisture and temperature, softens feed particles, extracts natural binders, and reduces friction which leads to greater production rates and pellet quality (Skoch et al., 1981).

The key to an efficient pelleting process is to set the parameters at the levels that will enable proper energy transfer from steam to feed particles. Besides steam quality, the moisture of the feed is a critical factor for efficient energy transfer. Generally, the thermal conductivity of the most used feed materials increases with increasing moisture. A level of 17% moisture in the conditioner is needed for efficient energy transfer. Below 17%, we need more steam (more energy) or more time (more capacity) to achieve the same result. That is why proper moisture optimization is needed to use the energy transferred through steam in the most efficient way.

Reduce shrinkage, improve sustainability

What about shrinkage? Shrinkage is not just a cost factor but a sustainability issue. We must not lose scarce and valuable materials and nutrients. Overall shrinkage tends to be around 1%. For global feed production as a whole, 1% annual shrinkage is equivalent to 15 years of Croatian compound feed production!

We help our industry to keep up sustainability efforts in terms of energy savings and shrinkage reduction by offering SurfAce. It’s a liquid preservative premixture with multiple economic and environmental benefits to the customer. It helps increase pellet output, improves conditioning, enhances the durability of the pelleted feed, reduces the formation of fines, and improves the overall quality of the final feed product. But most importantly, it optimizes feed production costs through energy savings and reduced labor input while also supporting the microbiological quality of the feed.

In the food sector, we have seen vast improvements in non-thermal food processing over the past decade. Examples include ultrasonication, cold plasma technology, supercritical technology, irradiation, pulsed electric field, high hydrostatic pressure, pulsed ultraviolet technology, and ozone treatment. I’m sure some of these technologies will be applied to feed processing one day. Until then, we must keep up our high sustainability standards and make it more efficient by applying all available tools in our feed processing toolbox.

References

Falk, D. “Pelleting Cost Center.” Essay. In Feed Manufacturing Technology III, edited by Robert R. McEllhiney, 167–90. Arlington, VA: American Feed Industry Association, 1981.

Skoch, E.R., K.C. Behnke, C.W. Deyoe, and S.F. Binder. “The Effect of Steam-Conditioning Rate on the Pelleting Process.” Animal Feed Science and Technology 6, no. 1 (1981): 83–90. https://doi.org/10.1016/0377-8401(81)90033-x.

By Marisabel Caballero, Global Technical Manager Poultry, EW Nutrition

COVID-19 and its aftermath, the Russia-Ukraine war, and climate change have all contributed to the current crisis. Energy price increases, supply chain difficulties, and raw material availability and rising prices are all consequences felt deeply across the animal production sector. It is now time that the industry puts in place mitigation plans and starts taking action.

Cost and availability of fats – a looming problem

The lockdowns during the COVID-19 pandemic in 2019/2020 caused a rapid drop in energy demand and therefore a cut in global oil production. In 2021, as normality was recovered, it was met an energy supply-demand imbalance leading to a global supply chain crisis that further stressed the delivery of energy sources. In 2022, one of Europe’s driest summers compounded by the Russian-Ukrainian war have greatly contributed to the increasing energy prices.

With two of the largest suppliers of grains and oil – Russia and Ukraine – at war, the global food supply and prices are also compromised. These two countries provide the world with more than 20% of all wheat and barley, 15% of corn and 60% of sunflower oil (FAO, 2022).

 

Moreover, corn and soybean yields in South America also fell sharply in 2019-20 and 2021-22 due to the impact of La Nina and are expected to continue being low in the next season.

Biofuels and animal production compete for crops

Biofuels have been seen as a solution to decrease fossil-fuel energy dependance. Before the war, global biofuel production was at a record high. However, in the current crisis, biofuels may be a contributor to the rise in food prices, as they use a significant percentage of feed-production crops. Only in the US, around 30% of the corn production goes into biofuels, while biodiesel accounts for 40% of soybean oil use (O’Malley & Searle, 2021).

For the animal production industry, maintaining performance and profitability during price hikes involves a combination of strategies. Feed production accounts for up to 70% of meat production costs. With the soaring energy and raw material crisis, feed production costs are on the spot.

The impact of fat in pelleting process output

Oils and fats generally are added to animal feeds as a rich source of energy and other essential nutrients. For the feed production unit, fats can be a pellet quality and energy output enhancer.

During the pelleting process, fat can increase production output, save energy, and prolong the production life of the die as it can act as a lubricant during the process. The feed ingredients contain fat, and a portion of fat/oil is usually added in the mixer. Too much in-mixer fat addition (higher than 2%) negatively affects pellet quality, and when fat is too low (no addition), the production rate decreases. Fats and oils are also added through a pellet coating system, which has been demonstrated to improve pellet quality.

In fats/oils high cost and shortage scenarios, feed production managers and nutritionists are faced with the challenge of production with higher constraints. In-mixer fat addition has consequences in throughput. However, in-mixer moisture addition facilitates conditioner steam penetration into the feed particles. With that, the efficiency of the process may be partially recovered.

Solving the efficiency & quality equation

Simply adding water into the mixer does not give optimal results: Surfactants, on the other hand, improve moisture penetration into the feed particles and increase lubrication at pellet die point. By reducing the surface tension of water, surfactants enable the feed particles to absorb and distribute the moisture uniformly.

Improved moisture retention facilitates the starch gelatinization during mash conditioning and passing through the pellet die. This is important to make the pellet more durable and the feed more digestible. It also reduces friction and hence the energy required for the pelleting process (improving milling efficiency). At the same time, surfactants aid with pellet water retention, minimizing feed shrinkage without increasing water activity, thus curbing feed microbial growth.

What difference can an effective surfactant make?

The effect of adding SURF•ACE to diets with different levels of fat was evaluated in more than 40 feed mills, with production capacities ranging from 5 to 20 tons per hour. SURF•ACE is added to water sprayed during mixing. This solution lubricates the mash feed, improves steam penetration and starch gelatinization, and thus reduces friction in the pellet die. The results show that, relative to pure water, the addition of SURF•ACE increases press throughout (t/h) by up to 25%.

 

Prioritize efficiency to compensate current challenges

Operating in a tight margin environment, feed mills always need to prioritize efficiency. The advantages of using SURF•ACE feed mill processing aid are clear: reduced energy consumption without compromising pellet quality; moisture optimization; and higher productivity.

During times of increasingly high ingredient and energy costs, it is even more important to utilize savings opportunities at every production stage.

By Marisabel Caballero, Global Technical Manager Poultry, EW Nutrition

More than five months after the start of the war in Ukraine, we are facing severe challenges in many aspects of our daily lives. The livestock industry is not excepted: the conflict affects the availability and prices of grains, fertilizers, oil, and biofuel, with the latter two having a direct impact on freight rate and shipping time.

Livestock producers face challenging times and must be rational and creative to continue managing profitable operations.

Increased prices for feed materials and energy 

Which strategies are available?

Maintaining performance and profitability during price hikes generally requests a combination of different nutritional strategies to, at least partially, compensate for the higher costs:

• using alternative feed ingredients such as by-products (while considering their limitations in terms of inclusion and quality)
• eliminating or reducing safety bands (especially to already used by-products)
• revising the use of feed additives according to current challenges in feed ingredients and at farms
• following on the previous one: strategic uses of enzymes, emulsifiers, and feed additives that may help the animals to improve their FCR.

The use of by-products – to what must be paid attention?

To guarantee safety and effectiveness, just as with any other feedstuff, it is necessary to check the nutrient composition of the alternative ingredients using feed composition tables and laboratory analysis. Besides the composition and nutrient concentration, the availability of these nutrients and palatability are critical parameters to consider. The feed/animal producer, when purchasing by-products, should:

• try to find his by-product sources close to the feed production site to reduce costs with logistics and transportation
• collect and test samples right after the by-products are delivered
• check if the feed mill is ready to handle and process those ingredients, especially when they are bulky or have flowability issues;
• compare the difference in animal performance and cost per unit produced when using traditional grain-soybean meal diets vs. by-product ingredients.

Processing for improving by-products’ quality

The safety and nutritional availability of by-products can be improved by chemical, physical, and biological treatments. Physical processes, such as drying, grinding, peeling, pelleting, extruding, and expanding, increase surface area and can deactivate certain anti-nutritional factors. Biological processes include the use of enzymes and microbial fermentation to tackle anti-nutritional factors and increase the nutritional value and digestibility of by-products.

Anti-nutritional factors negatively impact animal health

In addition, some agro-industrial by-products contain anti-nutritional factors (glycoalkaloids, tannins). These substances impair feed digestibility and affect animal performance (Jimenez-Moreno et al., 2019). Also, a high fiber content in the diet containing by-products limits the performance (Pereira et al., 2019).

Additives can help with cost reduction

Due to the increase in feed prices, it is also necessary to review the strategies for using feed additives in animal production. Enzymatic complexes or packages, mannanases, phytases, and xylanases, among others, might be a helpful option to maximize the yield of existing diets. For example, Edward et al. (2000) reviewed the benefits of using phytase for better phosphorus utilization in the diet (a raw material that also suffers from price increases since much of it is imported from China). However, the enzymes must be used properly. Nutritionists trying to create profitable formulations must check the availability of the substrate before including the enzyme in their formulation.

Other feed additives such as toxin binders reduce the exposure of animals to possible increased levels of mycotoxins. Gut health-improving additives such as pro/pre-biotics, phytomolecules, and MCFAs support gut health and performance, achieving similar levels as traditional diets.

These applications should be thoroughly evaluated as the return from their application may be interesting in increased by-products diets.

Using by-products in poultry means balancing several factors

In poultry feeds, using by-products to increase sustainability and cost-reduction is supported by ample research and practice, especially in feed for broilers and laying hens. Research focuses on finding the risks of the inclusion of various by-products and thus the levels at which their inclusion doesn’t hurt health and performance.

In summary, to use by-products in poultry diets, their cost, availability, nutritional composition, anti-nutritional factors, quality, as well as interaction and cost-effectiveness with feed additives (e.g., enzymes, toxin binders) must be considered to avoid or diminish the factors hindering animal health and performance.

Several factors must be considered when using by-products in poultry nutrition

DDGS are a valuable source of proteins – but limited inclusion

DDGS provide protein, energy, water-soluble vitamins, xanthophylls, and linoleic acid (Abd El-Hack et al., 2015). However, it also contains anti-nutritional factors such as non-starch polysaccharides (NSP) (Pedersen et al., 2014). A further disadvantage is their high danger of mycotoxin contamination (Schaafsma et al., 2009), even though Wang et al. (2007) and Damasceno (2020) indicate that up to 16% of DDGS can be included in broilers’ diets without negatively affecting health, performance, and meat characteristics.

Rice brans are one of the main available grain by-products

Rice brans constitute 10% of the paddy rice and thus represent a considerable global volume of the available grain by-products. As a feed ingredient, it is rich in protein, starch, fat, vitamins, and some trace minerals (Sanchez et al., 2019). Due to their susceptibility to oxidation (rancidity) and anti-nutritional factors such as phytase and trypsin inhibitors (Gallinger et al., 2004), the limit recommended for this by-product in poultry is around 10% (Hosseini et al., 2020; Sanchez et al., 2019).

Wheat by-products – optimally used with enzymes

Wheat by-products can also be a substitute for whole grains in poultry feeds; however, their NSP content can affect the viscosity of the digesta (Knudsen, 2014). When combined with enzymes (e.g., xylanase), wheat midds can be included in broiler and layer diets up to 30% without changes in performance (Abudabos, 2011; Salami et al., 2018). Dietary fiber has gained special attention due to its various beneficial effects on poultry. In this direction, moderate amounts of wheat bran – a source of insoluble fiber – have shown improved antioxidant status, gizzard development, intestinal digestive enzyme activities, and morphology in broilers (Shang et al., 2020).

By-products support pigs’ performance

When by-products are fed to pigs, swine nutritionists have reported that many of them can support pig growth and finishing performance and meat quality as well as immune response, milk yield, and milk quality in reproductive animals, among other productive parameters (Yang et al., 2021). For instance, Dong et al. (2019) concluded that, from a nutritional perspective, ingredients such as highland barley, buckwheat, glutinous broomcorn millet, non-glutinous broomcorn millet, and Chinese naked oat could potentially substitute corn in livestock feeding. Or as another example, Liu et al. (2019) suggest in their study that mulberry leaf can contribute to improvements in meat quality, with no adverse effects on the growth performance of finishing pigs. (Dong et al., 2019).

Pigs are susceptible to antinutritional factors

Especially pigs are susceptible to anti-nutritional factors

There are many different types of anti-nutritional factors that work in various ways. In swine feed, common anti-nutritional factors lower protein and amino acid digestibility and increase endogenous amino acid losses (Souffrant, 2001). This effect causes reductions in carcass yield for finishing pigs (Soto et al., 2019).

Options are available to compensate for the higher feed prices

Nutritionists have several options to optimize animal performance in the context of price increases. However, it is necessary to have a more holistic view of the business to know which of all the alternatives are the most suitable for each system. Understanding the strengths and weaknesses of each ingredient and feed additive and considering them in the light of literature and field data will yield the best understanding of how to use them effectively in successful animal production.