Organic Broadcaster

Care needed to supply methionine in organic poultry rations

By Kevin Ellis, National Center for Appropriate Technology

Chickens and other poultry need methionine in their diet for proper development of feathers, organs and muscles, as well as optimal egg production.

All species of poultry require a well-balanced ration in order to produce meat or eggs on a consistent basis. Since feed can be the number one cost in poultry production, farmers want to maximize feed conversion and ensure that flocks have the nutrition they need to be healthy and productive. Providing adequate daily nutritional requirements through mixed poultry feed supports the birds’ growth with no deficiencies. Most organic poultry rations easily cover vitamin requirements, but one amino acid requirement is hard to meet: methionine.

Methionine is one of the most important amino acids for poultry of all types. Amino acids are the chains of organic compounds in proteins that play important roles in animal growth and performance. Some of these amino acids can be synthesized in the body, but most have to be supplied through diet. Poultry cannot synthesize methionine on their own, and must rely on other sources to provide it.

Methionine aids in the development of poultry muscle and feathers, especially early in life. It contains sulfur, and supports the needs of other sulfur-containing amino acids, such as cysteine. It is also known as the “limiting” amino acid, since protein synthesis will be restricted based on the availability of this specific amino acid. A lack of methionine can lead to poor feather, organ or muscle growth, a depression in lay rate, and may even lead to cannibalistic flock behavior.

Methionine can be supplemented into a diet through a variety of different ingredients, the most common of which is fish meal. However, fish meal can negatively affect the taste of eggs if used excessively in layer diets. A “fishy” taste can sometimes be detected if fish meal is over 10 percent of the total ration.

Certified organic producers must take special care when including fish meal in poultry diets. Fish meal is regulated as a feed supplement rather than an ingredient under the NOP. This means that fish meal supplements must not contain any banned substances, but that the ingredients themselves do not need to be certified organic. Currently, it can be hard to find fishmeal products that do not include synthetic preservatives that are banned in organic production. This gap in supply has led farmers to look elsewhere to satisfy their poultry’s methionine needs.

Most cereal grains and other plant-based feed ingredients have a relatively low methionine content. Corn gluten, sesame seed meal and sunflower seed are among ingredients with higher methionine levels. However, these alternative ingredients can create other problems.

Balancing overall nutrients in a feed ration is critical to preventing unwanted side effects. For example, some diets using fish meal alternatives surpass crude protein requirements in order to meet the methionine need. This can lead to environmental consequences. Excess protein must be excreted, and with it more nitrogen. Nitrogen turns into ammonia, which can cause problems in bird health and living environment.

Lysine is another important amino acid that can be overlooked. Some producers mix feed that concentrates on methionine requirements, but completely leave out lysine sources, causing growth problems. Farmers must be mindful of the overall nutritional needs and balance when mixing a feed ration, and not just focus on meeting the need for methionine.

Synthetic methionine is widely used in commercial poultry production, but has restrictions placed on it in organic production. Synthesized DL-Methionine can only be mixed into organic feed rations at a rate of 2 pounds per ton for chickens (both broilers and laying hens) and 3 pounds per ton for turkeys and all other poultry. This rule has been up for debate for some time, with many wanting to ban the use of synthetic methionine altogether in organic poultry production. Many argue that poultry should be able to get their methionine requirements if raised on pasture, but others say that this would be hard to measure and could leave the birds with nutritional deficiencies.

Farmers are looking for regional-specific crops that can be added to a ration to fulfill nutritional needs. Current research is focusing on alternative on-farm sources of methionine. This includes plant-based alternatives, such as oats, and insect-based “flour” that could be supplemented into feed rations.

Research is also being done on poultry breeds in relation to the methionine issue. Some believe that slow-growing breeds are better suited for organic production, as they have lower methionine requirements. However, raising these birds increases production costs, as they must be fed for a longer time to get to market weight.

Meeting the methionine requirements for organic poultry is a tricky issue, and will not likely be solved by any one method. Solving this problem will need more research into different feed sources, rearing methods and livestock breeding. All of these factors can be experimented with on farm to see what works best for organic producers to raise healthy, productive flocks.

Kevin Ellis is a poultry specialist with the National Center for Appropriate Technology. 

From the January | February 2016 Issue

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