Measuring the crude protein and the essential amino acid content of sbm is crucial for producers in their decision-making process.
Sbm is the most common protein source in poultry diets, hence their nutrient value must be better measured.
Seth Naeve, Associate Professor and Soybean Agronomist at the University of Minnesota, said soybean and sbm have been valued primarily on an indirect measure of protein, which is crude protein. But crude protein alone is not the best measure of soybean value. Producers should also include nitrogen and essential amino acid content.
“For producers, it is important to identify the value proposition for their feed ingredients, measure that, and purchase accordingly,” he said.
Mr Naeve revealed that many factors impact soybean quality. Processing, soybean genetics, and conditions during handling and storage all affect quality, which can vary.
Location-specific factors (latitude, climate, and soil type) affect long-term quality trends. However, the annual variation in weather affects quality fluctuations.
“Rainfall patterns appear to have the greatest impact. Excessive rainfall reduces protein deposition in the seed and drought conditions during the seed-filling stages exacerbate this condition. Hence, weather patterns can blow variation up and change this over time,” he said.
Bob Swick, Professor at the University of New England, said US sbm has lower crude protein content than sbm from other origins.
However, it has higher critical amino acids (lysine, methionine, cystine, threonine, isoleucine, and tryptophan) and high sucrose.
His research shows that the lower the crude protein in sbm, the higher its sucrose content. Sucrose content is positively correlated with metabolizable energy, he added.
“The more protein in the feed, the more chickens will drink to get rid of the excess protein. This will lead to new problems as the birds will excrete more wet feces high in ammonia.”
Therefore, farmers should formulate feed according to the needs of the birds and not have excess protein. “They can use low-protein, high-amino acid soybean meal from soybeans grown in colder regions, like the northern US,” Prof Swick remarked.