Synthetic methionine use is currently limited to 1 kg and 1.5 kg per metric tonne (2, 2, and 3 lbs per short ton) of feed for organic laying hens, broilers, and turkeys and other poultry, respectively, in the United States of America. All other synthetic amino acids (AA) have been banned from use in organic poultry diets in this country. It is challenging to provide sufficient methionine (Met) to maintain bird growth and productive performance up to current industry standards given the recent restrictions that have been placed on synthetic Met. Without synthetic AA, Met requirements can alternatively be obtained for organic poultry by dramatically increasing dietary crude protein (CP) e.g. via additional inclusion of expeller-pressed soybean meal to the diets. However, this strategy leads to both major increases in feed costs and environmental concerns due to increasing nitrogen excretion, with concurrent rises in ammonia emissions, and corresponding welfare issues due to ammonia and litter quality. This review aims to examine feed ingredients that may contribute to a solution to this issue. Otherwise, further negative impacts may soon be felt from the current limitation on synthetic Met or a potential ban on its entire use in the future.
All Science Journal Classification (ASJC) codes
- Animal Science and Zoology