Written by: Dr. Jacquie Jacob, University of Kentucky
Peas are grown in temperate regions but are used as a food source worldwide. Traditionally peas rejected by the food industry were used in poultry diets. Now there are varieties of field peas grown specifically for animal feeds.
There are green and yellow varieties of field peas. There is very little difference in the nutrient content between green and yellow peas, but there are considerable differences between some pea varieties within each color category. Most of the differences are related to differences in the size of the pea and the thickness of the hull.
Genetics, seeding time, and the agronomic conditions under which the peas are grown affect the nutrient content of harvested peas. Peas are valued for both their protein and their energy. The protein content of field peas averages about 23%. As with most crops, the growing environment can affect protein content. Hot, dry growing conditions tend to increase protein content. The protein of field peas is highly digestible and has an excellent amino acid profile. Peas have high levels of lysine—more so than soybeans. Peas, like most of the pulse crops, are low in the sulfur amino acids methionine and cystine. The amino acids of field peas and canola complement each other and are an alternative combination protein source for poultry diets. The available energy content of field peas is similar to that of barley.
Peas can be a valuable energy and protein source for several different classes of poultry, as long as proper considerations are taken to assure that the diets meet the nutrient requirements of the specific birds. Unlike whole soybeans, which must be roasted for inclusion in poultry diets, spring-seeded peas have low levels of trypsin inhibitors, so they can be included in diets without being roasted. Field peas can be included as up to 40% of the content of layer diets, but 10% is a more practical level. Broilers and turkeys can be fed diets composed of 20% to 30% field peas without negatively affecting performance. Commercial feed enzymes can be added to increase protein digestibility in diets containing high levels of field peas.
Nutrient content of field peas
- Dry matter, 90%
- Crude Protein, 23.0%
- Methionine, 0.28% (82% available)
- Methionine + Cysteine, 0.50% (78% available)
- Lysine, 1.67% (87% available)
- Tryptophan, 0.19% (82% available)
- Threonine, 0.84% (83% available)
- Crude fat, 1.4%
- Ash, 3.3%
- Crude fiber, 5.5%
- Trypsin inhibitor activity, TIA/mg, 3.5
- Phytic acid, 1.2%
(Source: Pulse Canada)
Hickling, D. 2003. Canadian Feed Peas Industry Guide, 3rd Edition. Published by Pulse Canada, Winnipeg, Manitoba.