The 3 critical factors for successful pigmentation

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By Predrag Persak, Regional Technical Manager, EW Nutrition

We eat with our eyes. Depending on our cultural background and our experience, we prefer foods that have a certain appearance. Moreover, we regulate our taste and health expectations based on this appearance. In that equation, color plays an essential role. Think of healthy-looking salad, fruit, eggs, meat, and more. Certain foods are more appetizing and appear healthier – and, in many cases, are indeed so – when they display a certain color.

For poultry producers,  skin color and the yolk color of table eggs are of major concern. This concern is driven by the market (in certain regions,  skin and yolk pigmentation heavily affect buying preferences), by regulations, and by an interest in using all options to increase product quality with natural solutions.

critical factors for successful pigmentation

 

Where does poultry pigmentation come from?

Birds cannot synthesize pigments; they must take them up with their feed. Natural pigments have, besides their pigmenting properties, an antioxidant role in the bird’s organism. Unfavorable conditions can heavily influence the outcome of pigmentation. For producers looking to achieve reliable and consistent coloration, results are often unpredictable and disappointing.

Knowing the factors that affect pigmentation will help us to better understand how to achieve the desired level of pigmentation – or to identify, in hindsight what went wrong and when. In general, three different factors are decisive for efficient pigmentation:

  1. The quality of the product (type, content, and stability of the pigment)
  2. The amount of pigment ingested/absorbed/deposited
  3. The persistence of the pigment in the final product

1. Product quality is essential

The first point to be considered is the quality of the product you use, including type, content, and stability of the pigment in the product and the feed.

Content and quality of active substances determine efficacy

Concerning type and content, what matters more than the total amount of carotenoids is the level of active substances. The trans-isomers have higher efficiency than the cis-isomers and are decisive for pigmentation.

Natural pigments originate from natural sources that often vary due to growth conditions, harvest, and handling. Therefore, producers need to control incoming materials and conduct proper formulation during the production process. This is crucial in order to obtain an adequate level of pigments for appropriate pigmentation.

Adequate measures ensure the stability of the pigment in the product

Natural pigments are sensitive to light and air; they are easily oxidized. Also in the feed formulation there are many substances (e.g. oxidized forms of trace elements, choline, chloride) enhancing the oxidation of the pigments. Some precautions can be taken to protect natural pigments from oxidation:

  • Use of adequate package materials preventing the exposure to light and air
  • Use of antioxidants in the product as well as in the feed formulation

With these measures in place, the pigments are given adequate protection to ensure their stability.

2. Pigment intake, absorption, and deposition affect pigmentation

Every factor reducing the amount of pigment reaching its target deteriorates the quality of pigmentation. Below are the crucial factors producers need to take into account.

Feed intake is correlated to pigment intake

Assuming that the pigment is homogeneously distributed in the feed, feed intake directly determines the intake of pigment. Consequently, anything that affects feed intake also affects pigment intake and pigmentation. To that end, what is also decisive is particle size and homogeneous distribution of the pigment in the product.

The energy concentration in the feed is also a critical factor. Antinutrients, unpleasant taste, or inconsistent feed structure negatively influence feed intake.

Feed intake is also influenced by other elements:

  • the animal’s health status
  • environmental conditions
  • the availability of water
  • the housing system (free-range, farm)
  • feeding management factors (length of the feeding lines, separation of the feed in silo bins or through the feeding lines etc.).

Saponification plays a role in pigment absorption

Through saponification, the natural, esterified form of the pigment gets broken down and the pigment is separated from the fatty acid molecule. This step is necessary to enable the pigment to pass the intestinal wall. The higher the saponification, the better the bioavailability of the pigment.

Besides improving bioavailability, saponification also influences the particle size and the homogeneous distribution of the pigment particles in the product.

Some feed materials and nutrients influence pigment absorption

If pigments are used, it is essential to know that some feed materials or nutrients have a beneficial or adverse effect on the absorption or deposition of the pigments. The inclusion of saturated, low-digestible fats or fat sources decreases pigment absorption and, therefore, the efficacy of pigmentation, whereas unsaturated fats (oils) facilitate it. The addition of oil up to 5% linearly increases pigment deposition in the egg.

Nutrients such as Calcium or Vitamin A also change pigment absorption. In the case of calcium, the level and the source are decisive. High levels of fast soluble limestone or calcium levels higher than 4 % will decrease the absorption. Also, increased levels of Vitamin A are critical for the effectiveness of deposition, as Vitamin A and the pigment use the same transporters. This fact is very important in broilers if vitamin A addition is applied through the water.

Mycotoxins affect feed intake and absorption

Mycotoxins affect feed intake and absorption

The presence of mycotoxins in feed, especially DON, will reduce feed intake due to the bad taste. The gut health-impacting effect of the mycotoxins will increase the passage rate of the feed and will prevent adequate absorption through the intestinal wall. Additionally, the liver function is negatively impacted by the mycotoxins. This results in an affected serum transport and a lower storage capacity for the pigments, leading to lower deposition in the tissue.

Impacted gut health is bad for pigmentation, too

Good gut health is essential for good pigmentation, including the uptake/absorption of pigments, their deposition, but also already existing pigmentation. All health challenges that negatively affect digestion and absorption, such as dysbiosis, negatively influence pigment availability and pigmentation. In such cases, products or strategies improving digestibility and gut integrity can be a solution.

Specific diseases such as NCD, Coryza, helminthiasis, as well as coccidiosis are an important consideration. The first three diseases lower pigment deposition; coccidiosis, however, has multiple impacts. It not only affects digestion and absorption and, therefore, the ongoing pigmentation but also decreases the already existing one.

Coccidia cause damage to the intestinal wall and affect its activity, resulting in a lower absorption. Additionally, the animals lose weight due to an insufficient supply of energy. The consequence is a degradation of fat tissue where the pigments are stored. Furthermore, coccidiosis means oxidative stress for the animal – triggering a reaction of the organism. As pigments also serve as antioxidants, they are removed from the fatty tissues and used as antioxidants.

Within three days post-infection, pigment levels in the subcutaneous tissues, but also in the serum and the liver, drop to 0. Coccidiosis outbreaks occur more frequently in alternative housing systems, affecting broilers, but also laying hens. Paying close attention to coccidiosis and having a proper anticoccidial program in place is obligatory for good pigmentation.

3. Pigmentation ends when the final products are on the shelf

For the end consumer, an attractive color in the final products (such as pasta or the broiler carcass) is essential. Producers of these final products request to put more pigments into the feed, but is this always the solution? As described before, there are a lot of factors possibly impacting the process of pigmentation during animal production on the farm.

However, also in the pasta factory or in the slaughterhouse, pigmentation of the final products can be impacted. In the pasta factory, oxidizing enzymes can destroy the pigments making the pasta pale and unattractive. If they have issues with Salmonella in the slaughterhouse, the birds may be scalded in slightly hotter water. The defeathering afterward can cause the loss of the upper layer of the skin with the pigments.

These examples show why pigmentation is not just the responsibility of the animal producer, but rather continues up to the moment when the pasta or meat is ready for the consumer.

Control these 3 factors for best pigmentation results

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Pigmentation is a dynamic process that requires knowledge and attention. The better we control the influences, the more consistent and predictable the outcome. To that end, it is essential to use the product with the best quality, the best amount of pigment that can be not just ingested, but also absorbed and deposited, and with the best persistence in the final product and along its shelf life.

Keeping everything under control is not always possible or is extremely difficult. That is why choosing the right product is a vital link that will allow us to pay more attention to those things that we can find difficult to manage.

To meet all these demands, Colortek Yellow B is the best natural yellow pigment on the market. This highly concentrated natural yellow evidences optimal flowability, homogeneous mixing in feed and high stabilit, for reliable and consistent results. In addition, it boasts high bioavailability and is produced in the EU in a state-of-the art facility, with FAMI-QS certification and strict control of undesirable substances.




Reducing apo-esters: What are the alternatives?

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By Dr. Twan van Gerwe, Global Technical Director, EW Nutrition

A year ago, the European Commission announced regulation (EU) 2020/1400 – restricting the use of ethyl ester of β-apo-8’-carotenoic acid (generally known as ‘apo-ester’). Starting on 26 October 2021, this legislation restricts the use of apo-ester in poultry feed to 5 mg/kg for laying hens and 15 mg/kg for broilers.  

As apo-esters is a synthetic pigment – not naturally occurring in nature – this measure was taken because the authorities could not guarantee safety upon exposure to the user. Limiting the concentration in feed would reduce this risk to acceptable levels, according to the legislators’ decision.  

Why use apo-esters in the first place? 

Apo-ester is a synthetic yellow colorant, with good stability in premixtures and complete feed. It also has a high deposition rate in the yolk, making it an effective egg yolk colorant.  

Its ability to be applied through premix facilitates the proper dispersion in the final feed, which is relevant if micro-dosing systems are lacking in the feed mill. 

Why was the legislative change necessary? 

The legislative change which limits the use of synthetic apo-ester is based on the precautionary principle and in line with a broader market trend: away from synthetic (non-natural) components, towards the use of naturally occurring alternatives.  

The alternative to apo-ester

Natural yellow pigments, typically based on lutein and zeaxanthin produced from marigold oleoresin, are available in the market and can be used to reach the egg yolk pigmentation desired by the consumer. In contrast to apo-ester, these natural solutions are functional antioxidants, further contributing to the egg’s nutritious composition. 

Challenges for natural alternatives 

However, stability in premixtures and complete feed can be a challenge, with inconsistent yolk coloration as a risk. Safety can also be an issue, so it is important to ask for Quality Control measures routinely applied to avoid contamination with undesired substances (e.g., dioxins). To limit the risk of producing eggs with insufficient yolk coloration, it is important to select natural pigments with excellent stability and deposition efficiency. 

What is the best natural alternative to apo-ester? 

EW Nutrition’s natural pigment Colortek® Yellow B, produced with a proprietary technology, withstands the harsh conditions in premixtures, while the unique saponification process provides unparalleled deposition rates.  

Moreover, Colortek® Yellow B is the most concentrated natural pigment on the market, making it the perfect premix-delivered colorant in the egg industry. If you want to produce all-natural eggs without worrying about the stability of the product or the reliability of your egg coloration, please contact your local EW Nutrition person. 

 




Encapsulation: How a modern phytogenic feed additive makes all the difference

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By Technical Team, EW Nutrition

 

Secondary plant extracts have been shown to improve digestion, have positive effects on intestinal health, and offer protection against oxidative stress in various scientific studies in recent years. Their use as a feed additive has become established and various mixtures, adapted to the various objectives, are widely available.

However, their use in pelleted feed has been criticized for some time.  In particular, an unsatisfactory reproducibility of the positive influences on performance parameters is the focus of criticism. The causes invoked for the loss of quantifiable benefits are inadequately standardized raw materials, as well as uncontrollable and uneven losses of the valuable phytomolecules contained during compound feed production.

modern phytogenic feed additive makes all the difference

Delivery mechanisms influence product benefits

The animal production industry has long attempted to reduce its need for antibiotic drugs to an indispensable minimum. As a result, more natural and nature-identical feed additives have been used for preventive health maintenance. These categories include numerous substances that are known in human nutrition in the field of aromatic plants and herbs, or in traditional medicine as medicinal herbs.

The first available products of these phytogenic additives were simply added to compound feed. The desired parts of the plant were, like spices and herbs in human nutrition, crushed or ground into the premix. Alternatively, liquid plant extracts were placed on a suitable carrier (e.g. diatomaceous earth) beforehand in order to then incorporate them into the premix. These procedures are usually less than precise and may be responsible for the difficult reproducibility of positive results mentioned at the beginning.

Another negative factor that should not be underestimated is the varying concentration and composition of the active substances in the plant. This composition is essentially dependent on the site conditions, such as weather, soil, community and harvest time [Ehrlinger, 2007]. In an oil obtained from thyme, the content of the relevant phenol thymol can therefore vary between 30% and 70% [Lindner, 1987]. These extreme fluctuations are avoided with modern phytogenic additives through the use of nature-identical ingredients.

Effective encapsulation is key to stability

The loss of valuable phytomolecules under discussion can also be traced back to the natural origin of the raw materials. Some phytomolecules (e.g. cineole) are volatile even at low temperatures. In regular medicinal use, this effect is mainly employed with cold products. Thus essential oils, such as of mint and eucalyptus, can be added to hot water and inhaled via the resultant steam.

In the process of pelleting in compound feed production, temperatures between 60°C and 90°C are common, depending on the type of production. The process can last for several minutes until the cooling process is over. Sensitive additives can be easily inactivated or volatilized during this step.

A technical solution for the preservation of temperature-sensitive additives is using a protective cover. This is, for instance, an already established practice for enzymes. Such so-called encapsulation is already used successfully in high-quality products with phytogenic additives. The volatile substances should be protected by a coating with fat or starch so that the majority (>70%) of the ingredients can also be found after pelleting.

Unfortunately, complete protection is not possible with this capsule, as this simple protective cover can be broken open by mechanical pressure during grinding and pelletizing. New types of microencapsulation further reduce losses. In a sponge-like type of microencapsulation, if a capsule is destroyed, only a small proportion of the chambers filled with volatile phytomolecules are damaged.

High protection and recovery with Ventar D

A new type of encapsulation, developed by EW Nutrition for use in feed, delivers further optimization. Results show that the technology implemented in Ventar D ensures very high recovery rates of the sensitive phytomolecules even under demanding pelleting conditions.

In a comparative study with encapsulated products established on the market, Ventar D was able to achieve the highest recovery rates in all three tested scenarios (70°C, 45 sec; 80°C, 90 sec; 90°C, 180 sec). In the stress test at a temperature of 90°C for 180 seconds, at least 84% of the valuable phytomolecules were recovered, while the comparison products varied between 70% and 82%. A constant recovery rate of 90% was achieved for Ventar D under simpler conditions.

Phytomolecule recovery rates under processing conditions, relative to mash baseline (100%)

Phytomolecule recovery rates under processing conditions, relative to mash baseline (100%)

Site-specific release of active ingredients

The major gastrointestinal pathogens (like Clostridia spp., Salmonella spp., E. coli, etc.) are present across the gastrointestinal tract after the proventriculus. This leads to infection or lesions at different sites of preference, reaching up to ceca. Any feed-based solution should have a profound antimicrobial effect. It is, however, also crucial that active ingredients are released across the gastrointestinal tract, for a better contribution to intestinal health.

The unique, innovative delivery system used for Ventar D specifically addresses this point, which many traditional coating technologies do not.  Other encapsulation technologies tend to release the active ingredient either too early or too late (depending on the coating composition). The active ingredients in Ventar D reach across sites in the gastrointestinal tract and exert antimicrobial effects, supporting optimal gut health and improving performance.

Economically and ecologically sustainable

In the past, the losses mentioned in compound feed production and especially in pelleting were described as largely unavoidable. To obtain the desired effect of the valuable phytomolecules in the finished product, higher use of products was recommended and thus increased costs to the end-users and the associated CO2 footprint, lowering sustainability overall.

The modern encapsulation technology used in Ventar D now offers significantly better protection for the valuable phytomolecules and, in addition to the economic advantage, also offers more efficient use of the resources required for production.

References

Hashemi, S. R .; Davoodi, H .; 2011; Herbal plants and their derivatives as growth and health promoters in animal nutrition; Vet Res Commun (2011) 35: 169-180; DOI 10.1007 / s11259-010-9458-2; Springer Science + Business Media BV, 2011

Ehrlinger, M., 2007: Phytogenic additives in animal nutrition. Inaugural dissertation. Munich: Veterinary Faculty of the Ludwig Maximilians University in Munich.

Lindner, U., 1987: Aromatic plants – cultivation and use. Contribution to the special show – Medicinal and Spice Plants (Federal Garden Show 1987), Teaching and Research Institute for Horticulture Auweiler-Friesdorf, Düsseldorf.




Water Hygiene: The missing ingredient for successful ABF poultry

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By T.J. Gaydos

Water quality is a frequently overlooked part of animal production and it becomes even more important when producing animals in an antibiotic-free (ABF) system. Chickens drink almost twice as much water as they consume feed, and water hygiene is often a second-level priority. Microbes present in water can be primary or secondary pathogens or non-pathogenic. Consuming impure water can add a challenge to the immune system, negatively impacting performance. 

Water hygiene is essential

Water hygiene is essential for achieving antibiotic-free poultry production

Significant resources are spent on the correct nutrients in the diet and the correct additives for bird health. Water quality should be a priority, and a water quality monitoring program is essential for success in an ABF program. All things being equal, animals will perform better if they have access to high-quality water.

The variability of water quality in the grow-out region should determine how many water quality samples are taken. In highly variable areas, water quality should be measured at every season change on enough farms in every region to know if the solutes are changing. If the water quality is good and consistent, monitoring may be reduced significantly. Water quality should be a part of a “problem farm” work up or related to otherwise unexplained poor performance.

Water-soluble additives: Prevent biofilm

The use of water-soluble products is common in ABF production systems and their frequent use may provide a carbon source for bacteria. This, along with warm temperatures and slow water flow in enclosed water systems, makes the perfect environment for biofilm development.

It is important to frequently flush lines, give birds access to fresh water between additives, and sanitize water lines after using a product that can provide nutrients to bacteria in the line. The biofilm is a perfect location to harbor and protect pathogens from acids and mild or under-dosed disinfectants.

Designing a water quality program

Sample collection

The first step to building a water quality program is to understand the challenge on every farm. Correct sample collection is critical to achieving good results. Take a water sample from as close to the well as possible and submit for water quality analysis: pH, hardness, and minerals. This sample should also be submitted for bacterial load: total aerobic plate count (CFU) per mL and total coliforms per mL.

Monitor bacterial load

A drip sample should be collected from the end of the line for bacterial load analysis as well. This will help determine if the bacterial challenge begins at the source or is limited to the house. Additionally, a swab from the inside of the end of the water line should be taken to determine the level of biofilm. The total bacterial count should be less than 1,000 CFU/mL without fecal coliforms in a free-flowing sample, and total bacteria should be less than 10,000 CFU/mL on a biofilm swab.

Monitor water pH

Water should have a pH between 5 and 8. Water with a pH consistently lower than 5 can be damaging to equipment, while a pH over 8 reduces the efficacy of many disinfectants and can have a bitter taste to birds. Hard water can increase scaling of lines and equipment, leading to leaking seals. Scale also provides a matrix for biofilm formation, making cleaning and disinfection more difficult.

Clean and disinfect water lines

Cleaning water lines between flocks is the minimum program for ABF production. Stabilized hydrogen peroxide products are excellent for disinfecting water lines between flocks. The levels needed for proper disinfection of lines are generally too strong for birds, and the lines must be flushed prior to bird placement.

Water lines are often only cleaned in the house; it is important to periodically clean the lines that transport water from the well or water source to the poultry house as this may be a significant reservoir for bacteria. If the well is identified as a source of contamination, it is essential to seek the help of a qualified technician before adding any sanitizing product to a wellhead.

Designing a water quality program poultry farm

Continuous disinfection

Ideally, water should be continuously disinfected with a product that is approved for poultry consumption. One of the best products for continuous disinfection is chlorine dioxide, which is effective at reducing bacteria and also reducing the concentrations of some mineral components. High levels of iron in the water can create a favorable environment for E. coli and other bacteria such as C. perfringens.

In addition to disinfection, chlorine dioxide is an effective treatment to reduce soluble iron levels. High sodium and chloride levels can lead to flushing and promote the growth of some bacteria. If high levels of sodium and chloride are consistent across a grow-out region, it may be possible to decrease the levels in the feed to reduce flushing. If the levels of sodium and chloride are considerably high, reverse osmosis should be considered to improve water quality.

Bottom line: invest in high-quality water

Another effective product is stabilized hydrogen peroxide at an appropriate residual level for bird consumption. There are other options for water line sanitation that can be explored on a case-by-case basis.

There are excellent online resources [link] for poultry water quality. The important message remains, in any case, that investment in high-quality water is a critical step for success in ABF poultry production.

 

References

Austin, B.J., J. Payne, S.E. Watkins, M. Daniels, and B.E. Haggard. 2016. How to Collect Your Water Sample and Interpret the Results for the Poultry Analytical Package. Arkansas Water Resources Center, Fayetteville, AR, FS-2017-01: 8 pp.

Scantling, M. and Watkins, S. 2013. Identify Poultry Water System Contamination Challenges. FSA8011. University of Arkansas Division of Agriculture Research and Extension.

Watkins, S. 2008. Water: Identifying and correcting challenges. Avian Advice 10(3):10-15. University of Arkansas Cooperative Extension Service, Fayetteville, AR




Nutrition and feeding in ABF poultry production

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By T.J. Gaydos

Management practices and feed additive selection are often discussed when working in antibiotic-free (ABF) poultry production. Nutrition is another critical component of any agricultural animal system. Working with a qualified nutritionist will help ensure that the diet is correctly formulated with high-quality ingredients.

Chick Feed 

5 nutrition tips for antibiotic-free poultry production

1. Consider feed form and delivery

Feed form and delivery are nearly as important as the nutrient content of the formulation. If feed form or handling is improper and feed separates, is improperly mixed, or oxidized, the birds will not appreciate the effort that went to develop a balanced diet. A durable pellet or crumble is important to allow all birds to have equal access to a nutritionally complete diet with every bite.

Additionally, if the finished feed or individual ingredients are not stored properly, they may not have the same value that is attributed to them in the formulation process. Other than correct nutrient formulation, three parts of the diet that should be considered are feed additives, mycotoxin contamination, and lipid oxidation.

2. Prevent oxidative stress

The impact of oxidative stress on the intestinal mucosa, immune system, and performance is well-documented across species. Oxidized fat sources reduce the available energy, but equally significant to bird health is the reduction in vitamin availability, resulting in increased oxidative stress for the animal. Protecting the sources of fat and the finished feed is important to spare fat-soluble vitamins, specifically vitamin E.

Oxidized fat can also irritate the intestinal mucosa leading to decreased absorption of nutrients. The process of breaking down macromolecules during digestion and converting them to forms useful for further metabolism is a significant contributor to oxidative stress. The immune system is also a great contributor to oxidative stress. Immune cells use reactive oxygen species to kill pathogens that are phagocytosed.

A large portion of the immune system is located in the GI tract in order to protect the animal from pathogens crossing from the gut into the animal. In addition to being a contributor to oxidative stress, the immune system can be negatively impacted by oxidized feed (Liang et al., 2015). The combination of metabolic and immune activity in the intestines puts it at a high risk of damage from oxidative stress. It is vital to protect fat sources with synthetic or natural antioxidants; reducing the incoming stress from oxidized fat should be a priority to improve poultry health.

Chicken Feed

3. Mitigate mycotoxin risks

Another risk to bird health and mucosal integrity is mycotoxins. Diets containing mycotoxins may damage the mucosa of the GI tract directly or may damage other organs leading to significant health challenges and decreases in performance. Some mycotoxins or compounds created by fungi can disrupt the intestinal microflora by acting on bacterial cells, as many fungal metabolites are antimicrobial.

The best approach to managing mycotoxins is eliminating them from the system by purchasing high-quality grain and storing it appropriately. It is impossible to completely eliminate all risks of receiving ingredients contaminated with mycotoxins. An internal program should be developed to test the incoming ingredients and finished feed regularly for mycotoxins.

Knowing the challenging ingredient sources may help reduce the risk to highly susceptible birds like Breeders or chicks through dilution in formulation or the addition of toxin binders and/or enzymes. Several toxins may be found in a feed stuff and many of the mycotoxins are synergistic in their deleterious effects (Murugesan et al., 2015). Different binders have varying affinity for different mycotoxins; closely examining the product literature can help to choose the correct product to mitigate risk.

4. Choose optimal additives

Choosing the correct feed additive program for intestinal health, food safety, and growth performance depends on the specific challenges in the complex. When selecting a feed additive that is not FDA approved, it is important to base the decision as much as possible on scientific evidence through peer-reviewed research.

In addition to published data, internal testing within the production system is also helpful to ensure the product matches the local challenge. In a market saturated with “natural” products, it is essential to find a supplier that is trustworthy and is engaged in the success of the complex and health of the birds, not only in selling products. A partnership will be much more successful in the long term than only a buy/sell arrangement.

5. Manage expectations

When considering removing antibiotics from a program, the temptation is to expect natural products to completely replace the efficacy of antibiotics. This is an unreasonable expectation. The success of a transition to ABF production relies on modifying management practices as well. The vast majority of program success is related to attention to the details of husbandry, biosecurity, and sanitation. The remaining opportunity to improve health rests on the additive program.

References

Liang, Fangfang, Shouqun Jiang, Yi Mo, Guilian Zhou, and Lin Yang. “Consumption of Oxidized Soybean Oil Increased Intestinal Oxidative Stress and Affected Intestinal Immune Variables in Yellow-Feathered Broilers.” Asian-Australasian Journal of Animal Sciences 28, no. 8 (2015): 1194–1201. https://doi.org/10.5713/ajas.14.0924.

Murugesan, G.R., D.R. Ledoux, K. Naehrer, F. Berthiller, T.J. Applegate, B. Grenier, T.D. Phillips, and G. Schatzmayr. “Prevalence and Effects of Mycotoxins on Poultry Health and Performance, and Recent Development in Mycotoxin Counteracting Strategies.” Poultry Science 94, no. 6 (2015): 1298–1315. https://doi.org/10.3382/ps/pev075.

 




How animal nutrition can contribute to sustainability

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By Dr. Inge Heinzl, Editor, EW Nutrition

 

Nowadays, the whole world is talking about sustainability. Many efforts aim to maintain our world for future generations, creating a balance between our current needs and those of our children, grandchildren, and great-grandchildren. The right animal nutrition choices play a crucial role in achieving the challenging aim of sustainable animal production.

SWINE PIGS PIGLETS SUSTAINABLE AMR
Animal nutrition solutions can support producers’ sustainability contributions, from animal welfare to antibiotic reduction

Sustainability – an old concept now set out in writing

The idea of sustainability is not new. Already the first humans lived sustainably, taking only as much as they needed and the environment could cope with, using all parts of the animals they killed. The German Hannss Carl von Carlowitz (1645-1714) coined the term sustainability in his oeuvre “Sylvicultura oeconomica” to counter a threatening raw material crisis. Wood was one of the most important raw materials. Besides heating, it was used for shipbuilding and mining. This was the reason that extensive areas in Europe were deforested and became deserted. Observing the impending disaster, von Carlowitz ” (1713) stated that only as many trees should be felled as can grow back through planned reforestation, sowing, and planting.

The Brundtland Report (1987), a document created by the World Commission on Environment and Development, is reckoned to be the starting signal for worldwide discussions about sustainability. In 2015, the result of a meeting of 193 members of the United Nations was the Agenda 2030 with 17 sustainable development goals for a “world we want” that should be achieved by 2030.

Sustainable Development Goals (SDG) of the Agenda 2030, fixed by the UN in 2015

How can the feed sector contribute to sustainability?

The animal nutrition industry’s sustainability efforts play into different SDGs, notably no. 2, zero hunger, no. 3, good health and well-being, no. 12, responsible consumption and production, no. 13, climate action, no. 14, life below water, and no. 15, life on land. In addition to the overarching goal of fostering higher animal welfare (cf. Keeling et al., 2019), the feed sector’s measures center on three areas:

  1. Optimal use of feed resources, which includes optimizing feed conversion, preserving feed quality, and using alternative ingredients
  2. Preserving the environment by reducing ammonia and methane emissions and energy requirements
  3. Reducing antibiotics usage to maintain their efficacy for future generations

1.   Make best use of available resources

One of the 17 points on the list of the United Nations is “responsible consumption and production”.  For the feed industry, this means making the most out of available feed sources. Improvements in feed conversion, the maintenance of feed quality, and the use of alternative ingredients are all part of this.

Optimize FCR to utilize the available feed best

The feed conversion rate shows the amount of feed consumed in relation to the outputs produced, such as weight gain, eggs, or milk. The better or lower the feed conversion rate (FCR), the less feed you need to achieve your target, and the higher the yield. Products that improve feed conversion, therefore, can help to save resources.

Good feed conversion or an optimal utilization of nutrients depends on gut health. Only a healthy gut can digest the feed and absorb the nutrients adequately. Hence, products to improve feed conversion often do so by improving gut health.

Phytomolecules: proven to improve feed conversion

Herbs and their active components have been used in human and veterinary medicine for thousands of years to treat digestive tract diseases. Nowadays, products based on phy­tomolecules help improve feed conversion through their digestive, anti-inflammatory, and antimicrobial effects on the intestinal tract.

How do these three characteristics contribute to a better FCR?

  • Phy­tomolecules stimulate the secretion of digestive juices and the motility of the gut
  • Their antimicrobial effect supports a “healthy” balance in the microbiome, preventing damages of the gut wall by harmful microbes and, therefore, maintaining an optimal nutrient absorption
  • Their anti-inflammatory properties also contribute to good nutrient absorption and reduce endogenous nutrient loss

FCR improvements in broilers thanks to ACTIVO found in several studies

As phy­tomolecules are often volatile, EW Nutrition offers encapsulated phytomolecule-based products for the feed (ACTIVO product line). During episodes of elevated enteric challenge, e.g., weaning or following feed change, a liquid solution (ACTIVO LIQUID) can be applied via the waterline.

Enzymes help to make nutrients available

Some feed materials are hard to digest for certain animals. For example, pigs’ digestive systems do not have the enzymes required to break down non-starch polysaccharides (NSPs), such as cellulose, hemicellulose (ß-glucans and xylans), pectins or oligosaccharides. However, pig feed ingredients usually contain these substances.

Besides the non-usability of NSPs, the cage effect is a further problem. Cellulose and hemicellulose, water-insoluble NSPs, encage nutrients such as proteins or digestible carbohydrates. Encaged nutrients cannot be reached by the digestive enzymes and don’t become available to the animal.

Xylanases are available on the market to degrade structural substances in the feed and make them, as well as the nutrients they encaged, available for the organism.

Maintain the quality of your feed materials

Another possibility to save resources is the maintenance of feed quality. Bad weather conditions at harvest or incorrect storage can downgrade feed quality due to the development of molds and their mycotoxins or the oxidation of nutrients. Products mitigating the adverse effects of toxins, acidifiers that reduce microbial load, and antioxidants can help to keep your feed quality on a high level – or to re-establish it.

Mitigate the adverse effects of mycotoxins

Feed materials contaminated with mycotoxins harm animals in different manners and should not be used without further treatment. Mycotoxins are not visible – even if no molds are visible, mycotoxins might be present. Additionally, they are pH- and thermo-stable, meaning that mycotoxins produced in the raw materials on the field remain in the finished feed. As mycotoxins often do not cause apparent, specific symptoms but manifest in decreased performance, feed refusal or lower feed intake, and higher disease susceptibility, it is difficult to notice contamination.

Products such as SOLIS or MASTERSORB contain clay minerals (bentonite and montmorillonite) that adsorb the toxins. MASTERSORB GOLD and MASTERSORB FM also include toxin-adsorbing yeast cell walls and herbal substances to help protect the liver.

Feed spoilage through molds, yeasts, and mycotoxins wastes precious resources

Reduce microbes in the feed with acidifiers

Acidifiers based on organic acids counter harmful microbes in the feed in two ways. Most pathogenic bacteria are susceptible to low pH. The proliferation of, e.g., E. coli, Salmonella, and Clostridium perfringens is minimized at pH < 5 (cf. Fuller 1977). Acidic-tolerant beneficial bacteria such as Lactobacilli or Bifidobacterium, however, survive.

Other than antimicrobial activity, organic acids also cause a significant reduction in ammonia (Eriksen et al., 2014). This finding could be due to a reduction in the microbial deamination of amino acids, which would then be available for absorption, resulting in increased nitrogen digestibility and reduced ammonia excretion, as observed in monogastrics fed organic acids (Pearlin et al., 2020).

The acidifier product lines ACIDOMIX, FORMYCINE, and PRO-STABIL all help protect feed from contamination with pathogenic microorganisms.

Protect the feed’s nutrients from oxidation

The oxidation of nutrients in the feed decreases its nutritional value and, thereby, the value of the whole diet. Fat, proteins, fat-soluble vitamins, pigments, and other biologically active molecules, including sugars and phospholipids, can get oxidized. Metal ions and other pro-oxidative factors can affect the ingredients of the feed during mixing, storage, and feeding. The oxidation of fats and fat-soluble vitamins results in color changes or odors and – this is even more serious – in the production of harmful substances such as aldehydes and ketones. An oxidized feed can lead to oxidative stress in the animals, reduce their immunity, productivity, and livability.

To protect valuable ingredients, the timely addition of effective antioxidants such as STABILON is recommended.

Use alternatives to natural protein sources

Soybeans are an excellent source of protein in animal nutrition. During the last 50 years, soy production has increased from 27 million tons to 269 million tons, causing environmental degradation of forests and savannas (WWF, 2021). The use of alternative protein sources helps protect our environment.

Ruminants partly cover their protein requirements with the help of rumen bacteria. These bacteria can turn nitrogen from urea into bacterial protein, provided they receive enough energy available from carbohydrates. Thanks to its encapsulation, PROTE-N, a feed-grade urea-based nitrogen source, slowly releases nitrogen into the rumen, synchronized with the energy supply. PROTE-N affords producers a degree of independence from soybean protein without compromising nutritional quality.

Reducing soybeans in ruminant feeds helps to lower their environmental impact

2.   Preserve the environment

Animal production generates gases such as ammonia and methane that negatively impact the environment. Measures to reduce these gases help to protect plants, animals, us, and our globe.

Reduce ammonia by improving protein digestion

Besides nitrogen oxides, ammonia is one of the primary sources of nitrogen pollution. Ammonia damages ecological systems through acidification and nutritional oversupply. Fast-growing plants that need high amounts of nitrogen or plants that tolerate low soil pH proliferate, whereas more susceptible plants disappear, decreasing biodiversity. According to Max-Planck-Gesellschaft (2017), reducing ammonia emissions by 50 % could prevent 250.000 deaths caused by fine dust worldwide per year.

Improved protein digestion in animals reduces their ammonia production. Decreasing the intestinal pH through using organic acid-based products such as ACIDOMIX or FORMYCINE is essential for the activation and correct functioning of the enzymes responsible for protein digestion.

Reduce methane, the second most abundant greenhouse gas

Together with CO2, N2O, and three fluorinated gases, methane belongs to the greenhouse gases listed in the Kyoto protocol. Being over 25 times more potent than carbon dioxide at trapping heat in the atmosphere, it dramatically affects the earth’s temperature and the climate system (United States Environmental Protection Agency). Methane is a final product of feed fermentation in the rumen and is produced by methanogenic bacteria. Ruminants can produce 250-500 L methane per day (Johnson & Johnson, 1995).

Reducing methane production in ruminants is a critical step towards climate protection. Herbal substances can change the microbiome, leading to improved protein and fiber degradation and reduced methane production (Ku-Vera et al., 2020). ACTIVO PREMIUM is a phy­tomolecules-based product for ruminants that helps reduce their methane emissions.

Energy savings

To preserve the environment, reducing energy needs is also an important topic. Using the surfactant SURF-ACE in the pelletizing process, feed mills can cut 10-15 % of their energy consumption or produce up to 10-15 % higher pellet output without increasing their energy consumption. When moisture is added together with the surfactant, the emulsion of the dietary fat and the added water leads to better general lubrication of the machinery and improved press throughput.

FEED MILL POULTRY FEEDFeed mill efficiency is key to animal nutrition’s carbon footprint

3.   Reduce antibiotic use in animal production to keep this tool effective

Point 3 on the UN’s Agenda 2030 is good health and well-being. For many years, antibiotics, a very effective weapon, have been used to fight bacterial diseases. However, the occurrence of resistance is increasing. One of the reasons is the inappropriate use of antibiotics. These substances are often used preventively or for viral diseases against which they are ineffective. Also, the use of antibiotics as growth promoters at low dosages in animal production strongly contributed to the development of antimicrobial resistance.

Limiting antibiotic use to therapeutic treatment is possible through good farm management and feed supplements that support animals’ gut health, immune systems, and respiratory health. For this purpose, solutions ranging from phy­tomolecules (ACTIVO products, GRIPPOZON) to egg immunoglobulins (GLOBIGEN products, PROTEGG), products mitigating the impact of toxins (MASTERSORB products, SOLIS), beta-glucans/MOS (BGMOS), and acidifiers (ACIDOMIX, FORMYCINE) are available.

The feed sector has the tools to achieve more sustainability!

The animal nutrition industry provides many products to support animal producers in coping with their main challenges, including the shift to more sustainable production practices. Solutions exist to save feed resources, better protect the environment, and keep antibiotic tools effective. As an additional reward, implementing sustainability solutions leads to healthy animals with high performance. Let’s all help to preserve this planet for our next generations!

References

Eriksen, J., Nørgaard, J. V., Poulsen, H. D., Poulsen, H. V., Jensen, B. B., & Petersen, S. O. (2014). Effects of Acidifying Pig diets on emissions of AMMONIA, methane, and sulfur FROM Slurry during storage. Journal of Environmental Quality, 43(6), 2086–2095. https://doi.org/10.2134/jeq2014.03.0108

Fuller, R. (1977). The importance of lactobacilli in maintaining normal microbial balance in the crop. British Poultry Science, 18(1), 85–94. https://doi.org/10.1080/00071667708416332

Johnson, K. A., & Johnson, D. E. (1995). Methane emissions from cattle. Journal of Animal Science, 73(8), 2483–2492. https://doi.org/10.2527/1995.7382483x

Keeling, Linda, Håkan Tunón, Gabriela Olmos Antillón, Charlotte Berg, Mike Jones, Leopoldo Stuardo, Janice Swanson, Anna Wallenbeck, Christoph Winckler, and Harry Blokhuis. “Animal Welfare and the United Nations Sustainable Development Goals.” Frontiers in Veterinary Science 6 (October 10, 2019). https://doi.org/10.3389/fvets.2019.00336.

Ku-Vera, J. C., Jiménez-Ocampo, R., Valencia-Salazar, S. S., Montoya-Flores, M. D., Molina-Botero, I. C., Arango, J., Gómez-Bravo, C. A., Aguilar-Pérez, C. F., & Solorio-Sánchez, F. J. (2020). Role of secondary plant metabolites on enteric methane mitigation in ruminants. Frontiers in Veterinary Science, 7. https://doi.org/10.3389/fvets.2020.00584

Max-Planck-Gesellschaft. (2017, October 27). Reducing manure and fertilizers decreases atmospheric fine particles. Max-Planck-Gesellschaft. https://www.mpg.de/11667398/agricultural-emissions-fine-particulate-matter.

Pearlin, B. V., Muthuvel, S., Govidasamy, P., Villavan, M., Alagawany, M., Ragab Farag, M., Dhama, K., & Gopi, M. (2020). Role of acidifiers in livestock nutrition and health: A review. Journal of Animal Physiology and Animal Nutrition, 104(2), 558–569. https://doi.org/10.1111/jpn.13282

United Nations. (n.d.). How your company can advance each of THE SDGS: UN Global Compact. How Your Company Can Advance Each of the SDGs | UN Global Compact. https://www.unglobalcompact.org/sdgs/17-global-goals.

United States Environmental Protection Agency. (n.d.). Importance of methane. EPA. https://www.epa.gov/gmi/importance-methane.

von Carlowitz, H. C. (1713). Sylvicvltvra oeconomica, oder, Hausswirthliche Nachricht und Naturmässige Anweisung zur Wilden BAŬM-ZŬCHT: Nebst gründlicher darstellung, wie Zu FÖRDERST durch Göttliches Benedeyen Dem allenthalben und insgemein einreissenden Grossen Holtz-mangel: Vermittelst Säe-pflantz- und Versetzung Vielerhand Bäume zu prospiciren …: Worbey zugleich eine Gründliche nachricht von den in Churfl. Sächss. Landen gefundenen Turff Dessen Naturliche beschaffenheit, Grossen NÜTZEN, Gebrauch und nutzlichen verkohlung, Aus Liebe Zu BEFÖRDERUNG des Algemeinen Bestens beschrieben. Verlegts Johann Friedrich Braun.

World Wildlife Fund. (2021). Soja – die Nachfrage steigt. WWF Startseite. https://www.wwf.de/themen-projekte/landwirtschaft/produkte-aus-der-landwirtschaft/soja/.




Want to reduce antibiotic use? Biosecurity and sanitation are crucial

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By T.J. Gaydos

Biosecurity may not sound like an exciting topic at first, but it is a critical component of responsible poultry production. It is not enough to devise a strong biosecurity program; that program must also be followed by all people that interact within the system. It only takes one dirty boot or tire to ruin months of hard work.

Achieving good results with a flock largely depends on protecting the birds from biosecurity risks

Antibiotic reduction in poultry requires biosecurity

In a poultry operation, feed, people, and equipment constantly need to go in and out of farms and mills. Thus, no biosecurity program can be perfect. The intensity of the program needs to balance the realities of farming and the current disease pressure. The best program takes all of those into account, additionally considers local weather, availability of supplies, and company/farm staff. It is simple enough to be done even when no one is watching and should be easily scalable in case of increased disease pressure.

The rigorousness of a program must be in due proportion to the local circumstances. Having a biosecurity program that is too strict for the perceived disease pressure may result in people taking the path of least resistance. They probably will not follow instructions, especially if there is not enough monitoring and training to reinforce the value of biosecurity. On the other hand, a program with too lax guidelines will not have the desired effect.

The discrepancy between care requirements and separation

Unfortunately, the most valuable animals in an operation are often the most frequently visited by the most people. Pullets need closely monitored feedings, vaccines, and deworming. Breeders need eggs collected and shipped. Hatcheries require a labor force and maintenance. The feed mill and hatchery are central and overlapping points for all areas of the operation. The human and vehicle traffic at these locations must be closely monitored to reduce the risk of rapid disease transmission.

Feed mills are critical sites for biosecurity measures in poultry production

A physical barrier or sign indicating a biosecurity area on a farm or building entrance can help remind people of the program. Of course, these signs will not stop a disease from entering, nor a person determined to enter a site, but they will cause well-trained people to pause and reflect if they are making a sound decision.

Hygiene is a critical factor

It is well documented that hands and feet are significant transmitters of human and animal pathogens. Several studies have shown that hand washing can reduce absenteeism in school-aged children by 29-57%, thanks to a decrease in gastrointestinal diseases (Wang et al., 2017). Hand washing also reduces the incidence of respiratory illness in human populations by up to 21% (Aiello et al., 2008). Mycoplasmas can survive for one day in a person’s nose, for up to three days in hair, and up to 3-5 days on cotton or feathers (Christensen et al., 1994). Influenza viruses endure 1-2 days on hard surfaces (Bean et al., 1982) and more than a month in pond water (Domanska-Blicharz et al., 2010).

When building a biosecurity program, it is essential to consider the relevant pathogens of concern and the practical ways to reduce their risk of transmission.

How to establish an effective biosecurity program

Generally, biosecurity comprises two important parts:

  • Physical biosecurity, being the combination of all the physical barriers such as boot washes, signs, and disinfection
  • Operational biosecurity, covering the processes that protect an operation. This includes downtime, visiting birds in age order, time out for birds from people visiting sick flocks, and respect for physical biosecurity measures. Operational biosecurity starts with training, not only regarding the tasks required to be secure, but also the importance of disease prevention.

Establish several zones

When designing a program, consider four zones of increasing cleanliness: off-farm, on-farm, transition zone, and the animal housing area (Figure 1). Each zone should have a control point to reduce the pathogen load coming in, with exact measures depending on current disease status and bird value. These measures include vehicle sanitation and movement restrictions, footwear cleaning and disinfection, and use of personal protective equipment (PPE).

Figure 1: the four “cleanliness zones” in a farm

Increasing cleanliness from off-farm (red) to on-farm (orange) separated by a physical barrier. The entrance to the facility (transition zone; yellow) and the animal housing area (green).

Cleaning and disinfection are two of the core measures

As hands and feet are the main transmitters of pathogens, washing and sanitizing them is a priority. The outside of the house must be left outside, meaning that hands should be washed frequently and shoes sanitized between sites. Shoe covers should be put on when entering the house.

Cleanliness of the cell phone is often overlooked as a source of disease transmission (Olsen et al., 2020). It is a powerful tool: camera, notebook, light… and notoriously hard to clean. Cleaning and disinfection also apply to all shared tools and equipment that enter farms.

Prevent undesired “cohabitants”

Another critical point in biosecurity is the control of undesired pests and farm animals. Baits must be rotated, available where rodents are frequent, appropriately spaced, and secured from non-target animals. Habitats for pests need to be removed, the perimeter of the buildings must be clear of vegetation and debris, feed and grain spills picked up, and equipment stored away from the facilities. Pets and other farm animals should be kept away from the perimeter of the house and should under no circumstance be allowed to enter the facilities.

Tailored biosecurity programs keep your flock healthy

It is impossible to design a blanket biosecurity program for every operation. Understanding microbiology and disease transmission along with the risk points in a production system will allow a comprehensive plan to be developed. It is important to consider biosecurity as an investment in health and not an optional expense. No program is perfect, but small changes can significantly reduce the risk of pathogens entering the system and leading to major economic and animal welfare issues.

References

Aiello, Allison E., Rebecca M. Coulborn, Vanessa Perez, and Elaine L. Larson. “Effect of Hand Hygiene on Infectious Disease Risk in the Community Setting: A Meta-Analysis.” American Journal of Public Health 98, no. 8 (2008): 1372–81. https://doi.org/10.2105/ajph.2007.124610

Bean, B., B. M. Moore, B. Sterner, L. R. Peterson, D. N. Gerding, and H. H. Balfour. “Survival of Influenza Viruses on Environmental Surfaces.” Journal of Infectious Diseases 146, no. 1 (1982): 47–51. https://doi.org/10.1093/infdis/146.1.47.

Christensen, N. H., Christine A. Yavari, A. J. McBain, and Janet M. Bradbury. “Investigations into the Survival of MYCOPLASMA GALLISEPTICUM, Mycoplasma Synoviae And Mycoplasma Iowae on Materials Found in the Poultry House Environment.” Avian Pathology 23, no. 1 (1994): 127–43. https://doi.org/10.1080/03079459408418980.

Domanska-Blicharz, Katarzyna, Zenon Minta, Krzysztof Smietanka, Sylvie Marché, and Thierry van den Berg. “H5n1 High Pathogenicity Avian Influenza Virus Survival in Different Types of Water.” Avian Diseases 54, no. s1 (2010): 734–37. https://doi.org/10.1637/8786-040109-resnote.1.

Olsen, Matthew, Mariana Campos, Anna Lohning, Peter Jones, John Legget, Alexandra Bannach-Brown, Simon McKirdy, Rashed Alghafri, and Lotti Tajouri. “Mobile Phones Represent a Pathway for Microbial Transmission: A Scoping Review.” Travel Medicine and Infectious Disease 35 (2020): 101704. https://doi.org/10.1016/j.tmaid.2020.101704.

Wang, Zhangqi, Maria Lapinski, Elizabeth Quilliam, Lee-Ann Jaykus, and Angela Fraser. “The Effect of Hand-Hygiene Interventions on Infectious Disease-Associated Absenteeism in Elementary Schools: A Systematic Literature Review.” American Journal of Infection Control, 2017. https://doi.org/10.1016/j.ajic.2017.01.018.




Stop feed spoilage: How organic acids can preserve feed quality

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By Technical Team, EW Nutrition

Feed spoilage is a significant issue for the feed industry, leading to loss of nutrients, feed waste, and substantial economic issues for feed and animal producers worldwide (Leyva Salas et al., 2017). Fungal growth is one of the main causes of feed spoilage; it can occur at any stage of the feed production chain, including grain pre- and post-harvest processes, during feed production or storage. Organic acids and their salts are globally used in animal nutrition for microbial preservation and supporting animal health.

Organic acids help preserve animal feed and prevent spoilage through molds, yeasts, and mycotoxinsOrganic acids help preserve animal feed and prevent spoilage through molds, yeasts, and mycotoxins

The threat of molds and yeasts in animal feed

Yeasts and molds can have both positive and negative effects on products consumed by animals and humans. On the one hand, yeasts are used to produce fermented products, such as bread, wine, and beer. On the other hand, yeasts and molds promote the spoilage of raw materials, food, and feeds (Lowes et al., 2000). Molds are among the most potent food and feed spoilers. They can be very resilient to environmental stress, which is a concern in climate change scenarios (Perrone et al., 2020) and enables them to withstand feed preservation measures (Punt et al., 2020).

Several hundred species of molds and yeasts can invade a large variety of raw materials and feeds. They show an easy adaptation to different environments; for instance, they can grow and reproduce in media with pH levels ranging from 2 to above 9 (Tournas et al., 2001). However, the majority of yeasts and molds require free oxygen to grow and thrive.

Excess moisture, high water activity, and high temperatures in feedstuffs are the main mold growth factors that concern the feed industry (Mohapatra et al., 2017).  At storage, grains’ moisture content should not exceed 13%, and the water activity of raw materials, feedstuffs, and finished feed should be maintained below 0.8 (Dijksterhuis et al., 2019).  Controlling these points contributes to preventing the growth of most pathogens and undesirable microorganisms.

Mold growth reduces the nutritional value of feed, which affects animal health and performance Mold growth reduces the nutritional value of feed, which affects animal health and performance

The microbiology of molds and how they affect the feed

The microbial growth dynamic of grain storage depends on several factors, including the harvest season, grain temperature and moisture content, as well as the type of facility and its environment. For instance, in some areas, grains are harvested at the beginning of the cold season and stored through the following warm season. Storage molds constitute a significant threat to the quality of these raw materials, especially during the warm months, when the stored grains may become hotter than the surrounding environment. This leads to condensation, which increases moisture and water activity. Molds easily thrive in these conditions.

Storage molds reduce the nutritional and commercial value of grains and feeds. For grains, their commercial value decreases when the appearance of kernels changes in a manner recognized by the grain industry as kernel damage. The chemical composition of feeds may deteriorate due to enzymatic actions, resulting in a loss of nutrients (energy, vitamins) and the production of free fatty acids and other unwanted by-products (Reed et al., 2007).

Extensive research has established the factors that influence mold-induced deterioration during grain storage and which management strategies are required:

  • Moisture content and water activity (a function of the temperature, moisture content, and substrate) – Microorganisms have a limiting water activity below which they cannot grow; therefore, drying the grains below that critical level is part of an effective mold control strategy (Mannaa & Kim, 2017).
  • Temperature – Grain-contaminating molds thrive in tropical regions, where high temperature and humidity conditions predominate. In general, molds are inactive if the grains are stored below 20 °C (Mousa et al., 2013). However, the temperature of stored grains increases as molds begin to grow in the warmer and/or wetter parts of the grain/feed mass and feed, and heat is generated due to respiration, accelerating the deterioration rate. Moreover, the presence of a temperature gradient in the feedstuffs causes air to move, accelerating the transfer of moisture to cooler grain (Mannaa & Kim, 2017).
  • Grain quality, including previous storage conditions, insect infestation, presence of broken kernels, and impurities – When grain is too warm, the rate of insects’ breeding is higher (they respond to higher temperatures), the grain contains more humidity and may carry fungal spores. Broken kernels are an easier target for mold and insect infestations than whole ones, increasing the possibility of spoilage (Marcos Valle et al., 2021).
  • Duration of storage, management, and aeration influence the oxygen and carbon dioxide concentration in the grain mass, which plays a role in mold growth (Marcos Valle et al., 2021).

The consequences of storage deterioration include:

  • worse organoleptic properties (aspect, texture, taste, and aroma) of grains and feeds
  • more kernel damage,
  • higher fat acidity,
  • slight increase in protein content as non-protein constituents are consumed by mold respiration, causing
  • lower energy value of the grain/feed (Reed et al., 2007), and
  • lower content of vitamins A, B1, D3, E, and K.

Molds and mycotoxins: a toxic relationship for animal health

Beyond their negative impact on feed quality, some fungal genera such as Aspergillus, Penicillium, Alternaria, and Fusarium can produce mycotoxins, secondary metabolites that have toxic effects on humans and animals (Greco et al., 2015). Roughly 60% of raw materials produced for agriculture purposes worldwide are estimated to be contaminated by fungi and mycotoxins (Eskola et al., 2020). Mycotoxins can induce toxic, carcinogenic, and mutagenic reactions even at low concentrations. Their presence in the final feed is a sign of alert as, usually, these metabolites are resistant to technological treatments. Thus, it is important to stop them from entering the feed production chain (Leyva Salas et al., 2017).

Feed-contaminating Fusarium species produce mycotoxins such as trichothecenes, zearalenone, and Fumonisin.Feed-contaminating Fusarium species produce mycotoxins such as trichothecenes, zearalenone, and Fumonisin.

Organic acids: Unrivaled in preventing feed spoilage

It is crucial to reduce the feed losses and improve animal health by controlling fungal contamination at all stages of the feed production chain: from pre-harvest strategies on the field to post-harvest management during storage and even at feed processing. Throughout these processes, producers can apply different management practices. For instance, in field crops, fungal growth can be prevented through crop rotation and tillage; the use of fungicides is a later measure when mold presence exceeds critical levels.

Post-harvest management of grains and their by-products includes drying and storage management through moisture and temperature monitoring and aeration programs. Other spoilage-prevention measures include good hygiene practices and thermal treatments in feed production. However, feed producers and farmers face limitations in applying and linking such measures to tackle the occurrence of these undesirable pathogens (Dijksterhuis et al., 2019).

Certain organic acids, such as propionic, sorbic, benzoic, and acetic acids, have proven effective in preventing mold growth and feed spoilage. These organic acids are used globally now, not only for improving animal nutrition but also for supporting animal health (Dijksterhuis et al., 2019).

Pro-Stabil BSL is a product that harnesses the feed preservation effects of organic acids and combines them with surfactants. This means that it can offer a strong yeast and mold inhibition while maintaining the moisture in feed, thus reducing the risk of microbial challenges while prolonging the shelf life of feedstuffs and compound feeds.

Trial results: Pro-Stabil BSL is a great tool to reduce mold growth and manage moisture

Pro-Stabil BSL contains a synergistic blend of organic acids and a surfactant that leads to

» Improved moisture dispersion in the feed

» Increased water retention (reduced water activity)

» Improved anti-mold agent dispersion in the feed and grain

Trial results show a significant decrease in mold growth when Prostabil BSL was added to compound feed. In addition, when moisture was added at 2%, moisture from the environment was also observed, but the mold counts still decreased (Figure 1).

Figure 1: Effects of Pro-Stabil BSL with addition of 2 % moisture on feed quality indicatorsFigure 1: Effects of Pro-Stabil BSL with addition of 2 % moisture on feed quality indicators

When adding Pro-Stabil BSL to animal feed, the following benefits can be expected:

  • Reduction and prevention of mold growth and recontamination
  • Improved moisture management
  • Improved feed mill efficiency production
  • Improved microbiological quality of grains and feed
  • Shrinkage management by increasing moisture in feed with no risk of mold development
  • Reduced water dissipation

Mold growth can lead to sensory defects in feed and reduce its nutritional value. It can also harm animals through the production of mycotoxins. Pro-Stabil BSL offers a safe solution that is also easy to handle. Using the preservative properties of organic acids, Pro-Stabil BSL helps to reduce feed spoilage and its associated effects on animal health and performance.

References

Dijksterhuis, Jan, Martin Meijer, Tineke van Doorn, Jos Houbraken, and Paul Bruinenberg. “The Preservative Propionic Acid Differentially Affects Survival of Conidia and Germ Tubes of Feed Spoilage Fungi.” International Journal of Food Microbiology 306 (2019): 108258. https://doi.org/10.1016/j.ijfoodmicro.2019.108258.

Eskola, Mari, Gregor Kos, Christopher T. Elliott, Jana Hajšlová, Sultan Mayar, and Rudolf Krska. “Worldwide contamination of food-crops with mycotoxins: Validity of the widely cited ‘FAO estimate’ of 25%.” Critical Reviews in Food Science and Nutrition 60, no. 16 (2020): 2773-2789. https://doi.org/10.1080/10408398.2019.1658570

Greco, Mariana, Minna Kemppainen, Graciela Pose, and Alejandro Pardo. “Taxonomic Characterization and Secondary Metabolite Profiling Of Aspergillus Section Aspergillus Contaminating Feeds And Feedstauffs.” Toxins 7, no. 9 (2015): 3512–37. https://doi.org/10.3390/toxins7093512.

Harein, P., & Meronuck, R. (1995). Stored grain losses due to insects and molds and the importance of proper grain management. In V. Krischik, G. W. Cuperus, & D. Galliart (Eds.), Stored product management (pp. 29e31). Oklahoma Cooperative Extension Service Publication. E-912.

Leyva Salas, Marcia, Jérôme Mounier, Florence Valence, Monika Coton, Anne Thierry, and Emmanuel Coton. “Antifungal Microbial Agents for Food Biopreservation—a Review.” Microorganisms 5, no. 3 (2017): 37. https://doi.org/10.3390/microorganisms5030037.

Lowes, K. F., C. A. Shearman, J. Payne, D. MacKenzie, D. B. Archer, R. J. Merry, and M. J. Gasson. “Prevention of Yeast Spoilage in Feed and Food by the Yeast Mycocin Hmk.” Applied and Environmental Microbiology 66, no. 3 (2000): 1066–76. https://doi.org/10.1128/aem.66.3.1066-1076.2000.

Mannaa, Mohammed, and Ki Deok Kim. “Influence of temperature and Water activity on Deleterious fungi AND Mycotoxin production during grain storage.” Mycobiology 45, no. 4 (2017): 240–254. https://doi.org/10.5941/myco.2017.45.4.240.

Marcos Valle, F. J., Castellari, C., Yommi, A., Pereyra, M. A., & R. Bartosik. “Evolution of grain microbiota during hermetic storage of corn (zea mays l.).” Journal of Stored Products Research 92 (2021): 101788. https://doi.org/10.1016/j.jspr.2021.101788.

Mohapatra, D., Kumar, S., Kotwaliwale, N., and K. K. Singh. “Critical factors responsible for fungi growth in stored food grains and non-Chemical approaches for their control.” Industrial Crops and Products 108 (2017): 162–182. https://doi.org/10.1016/j.indcrop.2017.06.039.

Mousa, W., Ghazali, F. M., Jinap, S., Ghazali, H. M., and S. Radu. “Modeling growth rate and assessing AFLATOXINS production by Aspergillus flavusas a function of Water activity and temperature on polished and brown rice.” Journal of Food Science 78, no. 1 (2013). https://doi.org/10.1111/j.1750-3841.2012.02986.x.

Perrone G, Ferrara M, Medina A, Pascale M, and N. Magan. “Toxigenic Fungi and Mycotoxins in a Climate Change Scenario: Ecology, Genomics, Distribution, Prediction and Prevention of the Risk.” Microorganisms 8, no. 10 (2020): 1496. https://doi.org/10.3390/microorganisms8101496.

Punt, Maarten, Tom van den Brule, Wieke R. Teertstra, Jan Dijksterhuis, Heidy M.W. den Besten, Robin A. Ohm, and Han A.B. Wösten. “Impact of Maturation and Growth Temperature on Cell-size Distribution, Heat-Resistance, Compatible Solute Composition and Transcription Profiles of Penicillium Roqueforti Conidia.” Food Research International 136 (2020): 109287. https://doi.org/10.1016/j.foodres.2020.109287.

Reed, Carl, Stella Doyungan, Brian Ioerger, and Anna Getchell. “Response of Storage Molds to Different Initial Moisture Contents of Maize (Corn) Stored AT 25°C, and Effect on Respiration Rate and Nutrient Composition.” Journal of Stored Products Research 43, no. 4 (2007): 443–58. https://doi.org/10.1016/j.jspr.2006.12.006.

Tournas, Valerie, Michael E. Stack, Phillip B. Mislivec, Herbert A. Koch, and Ruth Bandler. “Bacteriological Analytical Manual Chapter 18: Yeasts, Molds and Mycotoxins.” U.S. Food and Drug Administration. April 2001. https://www.fda.gov/food/laboratory-methods-food/bam-chapter-18-yeasts-molds-and-mycotoxins.




Harvest to bring significant quality challenges for feed, says EW Nutrition [Press Release]

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VISBEK, GERMANY, 23 August – Bad news for feed producers: after supply chain disruptions and raw material unavailability, now weather-related challenges in Europe will most likely affect this year’s crop quantity and quality. Cold temperatures, heatwaves, tornados, and hailstorms are expected to adversely affect the quality and quantity of the harvest.

The moisture brought by the rainfalls is generally expected to affect the quality of the crops. The torrential rains in France, Germany, etc. have darkened Central and Western farmers’ prospects: while the quantity may be there, the quality of wheat and corn is under question. Sprouting grains, diseased crops, and fungi may dampen the optimism brought by numbers alone.

Further east, droughts have posed different issues. Still, countries such as Romania and Bulgaria seem to have weathered the challenges somewhat better and are seeing YoY increases in their wheat and corn crop output.

In Great Britain, rainfall has not caused dramatic drops in crop output but has nevertheless greatly increased mycotoxin risk up to a “moderate to high” level.

Depending on the type of mycotoxin, weather challenges and storage conditions are the most common contributors to severe infestation. This year’s intemperate weather has, in fact, been ideal for a large spectrum of fungi. Fungal risks can be calculated at the two critical times: at flowering and at harvest and baling, when there is an increased risk of storage molds and mycotoxin production.

Preliminary analysis shows Europe’s wheat crops at potential risk of DON, as well as potentially Aflatoxin and Fumonisin infestation and more. Specialists continue to collect and monitor harvest results and adjust recommendations; however, we can definitely expect the presence of moderate, if not quite high levels of mycotoxin risk this year.

 

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4 ways to cope with increased feed prices

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

In the last few months, the prices for feed grains and oilseeds such as soybeans have been climbing to multi-year heights. In part, this can be explained by high corn purchases by China and increasing export duties in Russia. The most significant cause, however, are weather events in producing countries: Just in the last year, droughts in the USA, Canada, and France raised the price of wheat by 40 %, the worst La Niña climate event in 91 years and the drought in China’s biggest corn-growing area made corn about 100 % more expensive, and soybeans carry a 40 % higher price tag because of dry conditions in Argentina.

These events are a stark reminder that for global agriculture climate change impacts are already a reality. High feed costs are an enormous challenge for the whole agricultural sector and sustainable strategies need to be adopted to enable a more efficient use of resources, both in the short and long term. This article explores possibilities to cope with the current situation. Through understanding the positions of farmers, integrators and feed millers and using targeted feed additive solutions, we can achieve a responsible use of resources that makes animal production more resilient to feed price increases.

Feed cost issues? Always start with this

The first question producers need to ask themselves is always if there is any step in the production process that could be done more effectively. Similar to biosecurity programs, the basic steps seem self-evident, but to consistently implement them in the complex on-farm reality requires regular checks.

Feeding as “exactly” as possible

In case of high prices, the feed raw materials should be used as responsibly as possible:

  • Protein and energy content (but also other components, such as minerals and vitamins) must meet the requirements of the animals – age and production phase are decisive for the calculations.
  • Given variations in raw material quality, it is important to exactly determine nutrient contents to avoid over- and under-supply. For this purpose, technologies like the near-infrared spectroscopy (NIR) can be used.

Using locally available sources

In the initial stages of price hikes, it is often possible to resort to locally available sources, e.g., using sunflower or flaxseed meal to replace soybeans. Unfortunately, with increasing demand, these feed materials will usually become more expensive as well, and might not be suitable alternatives anymore. In general, however, it is worth using a maximum of local ingredients: they are often cheaper and less susceptible to transport and trade difficulties.

Feed additive solutions: use what is available in the best possible way

Once these first measures are exhausted, it is time to draw on industry solutions to derive maximum value out of the available feed ingredients. Let us consider four approaches that improve feed conversion and feed quality, adjust feed composition, and optimize feed production processes.

1.   A critical goal: improving the feed conversion rate

The most direct way to better utilize feed is to improve the animals’ feed conversion rate, with the help of the right supplements. Different product groups contribute to this aim in different ways.

1.1 Phytomolecules fight on different fronts

Phytomolecules are well-known for their antimicrobial effects against pathogenic bacteria (Zhai et al., 2018). Phy­tomolecules shift the balance of the microbiome towards the beneficial side (eubiosis instead of dysbiosis) and promote gut health. A healthy gut is able to digest the feed and absorb the nutrients in an efficient way.

Another value of phy­tomolecules is their digestive effect. They stimulate the secretion of saliva, gastric juice and digestive enzymes, and favor an adequate gastrointestinal motility, which leads to improved nutrient utilization (Jones, 2001; Mendel et al., 2017).

In trials testing the phytogenic Activo product range, supplemented animals showed the following FCR improvements compared to non-supplemented control groups (Figure 1):

Figure 1: FCR improvements for animals receiving Activo

1. 2 Enzymes improve nutrient availability

Even a corn-soybean meal diet is not fully digestible for monogastric animals. However, when feed prices increases, producers likely need to include more alternative ingredients in the diet that are much less digestible. Typically, these ingredients are rich in antinutritional factors such as non-starch polysaccharides (NSPs), which can cause detrimental effects on gut health.

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

Here is the point of attack for enzymes that enable a complete nutrient utilization: Making these substances available for the animals increases the energy content of the diet and, in the end, improves FCR. An example for laying hens receiving wheat-based diets can be found in Figure 2: Axxess XY, a xylanase, significantly improved feed utilization by the hens.

Figure 2: FCR in layers receiving Axxess XY, compared to control group (kg feed / kg egg mass)

1.3 Antioxidants maintain energy content of the diet

Corn Distiller’s Dried Grains with Solubles (DDGS), a by-product of corn distillation processes, are used as an alternative to corn. In DDGS, the starch content is removed, but fat is concentrated, reaching about three times the fat level of corn. This is the reason why the energy content in DDGS and corn is similar. This makes DDGS an attractive ingredient for monogastric diets; however, fat,  especially at hot temperatures in the summer, can be oxidized. The resulting rancidity and the accompanying destruction of vitamins, pigments, and amino acid leads to a decrease in the diet’s bioavailability and energy content and to poor feed conversion.

The use of antioxidants can stabilize DDGS and other fatty ingredients in the feed, maintaining nutrient integrity and availability. Figure 3 shows the performance benefits of using antioxidant product Santoquin in pork finisher diets in the USA containing 30% of DDGS.

Figure 3: Performance results for pigs receiving Santoquin (trial with Midwest pork producer)

In  poultry production, the use of DDGS is not as common as in swine. Antioxidants, however, can still help to protect the nutrients, maintain the energy content and improving FCR. The results from an extensive 2015 field study for broilers fed a diet without DDGS (shown in Figure 4) showed a net ROI of 6.7 to 1.

Figure 4: FCR in broilers receiving Santoquin, compared to non-supplemented control group

1.4 Organic acids improve intestinal processes

Organic acids, or acidifiers, can improve the gut microbiome, feed utilization, and gut health in production animals. The gut microbiome balance is aided by lowering the population of pathogenic bacteria susceptible to low pH, such as E. coli, Salmonella, and Clostridium.

Organic acids also directly attack pathogens by entering bacterial cells and changing the internal pH. Commensal bacteria such as Lactobacilli and Bifidobacteria survive as they can tolerate lower pH conditions. As pathogens constitute nutrient competitors, eliminating them improves gut health, which, is the most important precondition for optimal nutrient utilization.

The acidifying effect of organic acids furthermore favors digestion and nutrient utilization: for example, for weaned piglets that not able to produce enough HCl in the stomach, a low stomach pH is important for the activation of the proteolytic enzyme pepsin. Besides a non-optimal use of nutrients, undigested protein arriving in the intestine leads to the proliferation of undesired pathogens, decreasing health and performance.

Organic acids, therefore, improve FCR directly, by promoting nutrient utilization through the stimulation of enzymes, and indirectly, by enhancing gut health.

2. Improving feed quality

Feed quality is not only a question of raw material quality. Feed additives play an important role in ensuring feed safety and enabling optimal utilization by the animal.

2.1 Mold inhibitors preserve the feed’s value

Molds reduce the nutrient and energy content of the feed (table 1) and have a negative impact on animals’ growth performance (table 2). Active water is the crucial point for mold growth. Compared to bacteria, which need about 0.90 – 0.97 Aw (active water), most molds require only 0.86 Aw.

Mold inhibitors contain different ingredients. Surfactants bind the free water, so that the moisture of the feed persists, but the active water important for molds is reduced. Organic acids, as already mentioned before, have antifungal properties. Together, they reduce molds and prevent the degradation of energy in the feed.

Table 1: Nutrient loss in corn infested with molds

Table 2: Comparison of 28-day-old chicks performance fed not-infested and molded corn


2.2 Mitigating the negative impact of mycotoxins

Mycotoxins contamination of grains can occur in the field, during raw material harvesting, transportation, storage, handling, and even during feed processing and storage. By mitigating the negative effects of mycotoxins – such as gut and liver inflammation, kidney degeneration or reproductive disorders – the animals’ health and performance can be maintained. In today’s contamination scenarios, it is absolutely necessary to use products that adsorb mycotoxins and contain their harmful impact on animals.

The effectivity of such products in animals is crucial. Table 3 shows an optimal experimental design and Figure 5 shows the results of its application: a total recovery of the performance pays off.

Table 3: Trial design, impact of Mastersorb Gold on broilers challenged with zearalenone and DON-contaminated feed

Figure 5: Average FCR for broilers, with or without zearalenone and DON challenge, with or without Mastersorb Gold supplementation

2.3  Surfactants for microbiological control and high pellet quality in the feed mill

Moisture is important. Too dry feed results in poor palatability and digestibility, and lower pellet quality. Also moisture loss has a direct impact on production and profitability.

The use of surfactants, makes it possible to bind the moisture to the feed, reaching a larger contact surface between water and feed particles, and improving starch gelatinization and pelleting efficiency. The improvement in starch gelatinization leads to a higher pellet quality, a lower proportion of fines and a higher content of metabolizable energy.

Moreover, moist steam has a better antimicrobial effect than dry steam, leading to lower fungal and bacterial growth and preventing the production of toxins. The pelleting temperature can also be lower, protecting the nutrients.

Figure 6 shows how the use of SURF•ACE, a synergistic blend of organic acids and surfactants, improves pellet durability, moisture content, and mold occurrence for beef and poultry pellet feed.

Figure 6: Improvements in pellet durability, moisture content and mold through using SURF•ACE

3.   Using feed alternatives in ruminants – partial replacement of protein feed by urea

Ruminal bacteria are able to synthesize amino acids and, subsequently, generate a high-quality protein out of acid amides, a group of non-proteins occurring during the synthesis and degradation of proteins. What they require to do this is enough energy, minerals, and trace elements available in the feed (Weiß et al., 2011). When the bacteria arrive in the abomasum and in the small intestine they, or rather their proteins, are degraded by enzymes together with the undegradable rumen protein into useful amino acids.

With the aid of ruminal microbes, ruminants therefore partly cover their protein requirement through non-protein nitrogen. The most well-known is urea. It is critical that the urea given to animals has a degradation rate similar to other energy sources the animal consumes. Otherwise, there will be an imbalance between the quantity of usable nitrogen and the energy required for microbial protein synthesis: The urea accumulates in the rumen, becoming toxic for the microbiota and creating metabolic disorders.

Special coating technology allows for nitrogen to be released at a rate close to that of protein degradation of the main vegetable protein sources (e.g., soybean meal). This leads to a more constant nitrogen supply for the microorganisms and results in maximal synthesis of microbial protein.

4.   Save costs in the production process

Besides high pellet quality, feed millers seek to maximize production efficiency. Factors contributing to this target are the amount of fines to be reprocessed, the utilization of steam, the pellet throughput and the energy demand. Once more, the moisture of the feed is of decisive importance. Substances can be added to the feed to achieve an optimal moisture content. These substances bind free water by generating an emulsion of dietary fat and the added water.

Besides the positive effects on pellet durability, moisture content and mold growth shown above, this leads to a better general lubrication of the machinery: The addition of feed mill processing aid SURF•ACE leads to a 10-15 % lower energy demand or a higher production output without increasing energy consumption (Figure 7), depending on the mill’s requirements. Good machinery lubrication additionally reduces wear and tear, another important dimension of production efficiency

Figure 7: Improvements in pellet output and energy efficiency through using SURF•ACE

Producers can rise to the challenge of rising feed prices

Rising feed costs pose a significant challenge to everyone in animal production. We are all compelled to look for alternatives to optimize the utilization of resources. This firstly involves a critical look at the efficiency of every step in our operations, but also includes utilizing targeted feed additives. Various measures are available for animal producers to optimize feed conversion, improve feed quality, and resort to alternative ingredients. In feed production, tools are on hand to optimize the manufacturing processes, improve feed quality, and make a positive impact on animal performance. Feed price fluctuations will continue to challenge our industry. Still, while tackling short- and medium-term difficulties, we can also strategically build resilience – and take the measures today that will contribute to our long-term ambitions for sustainable and profitable production.

 

References

Jones, G. “Leistungsstarke Tiere und Verbraucherschutz stehen nicht im Widerspruch – Wirkung eines phytogenen Zusatzstoffs / High-performing livestock and consumer protection are not contradictory – Impact of a phytogenic additive.” Kraftfutter/ Feed Magazine 12 (2001): 468-473.

Mendel, M., Chłopecka, M., Dziekan, N., & Karlik, W. (2017). Phytogenic feed additives as potential gut contractility modifiers—A review. Animal Feed Science and Technology, 230, 30–46. https://doi.org/10.1016/j.anifeedsci.2017.05.008.

Weiß, J.W., S. Granz, W. Pabst. Tierproduktion. Thieme Verlag (2005):155-159.

Zhai, Hengxiao, Hong Liu, Shikui Wang, Jinlong Wu, and Anna-Maria Kluenter. “Potential of Essential Oils for Poultry and Pigs.” Animal Nutrition 4, no. 2 (June 2018): 179–86. https://doi.org/10.1016/j.aninu.2018.01.005.