Hydrolyzed Soy Protein Isolate Sustains High Nutritional Performance in Veal Calves

Abstract

Milk replacers containing skim milk powder or a mixture of whey and soy protein provided by a hydrolyzed soy protein isolate or a heated soybean flour were fed to 1-mo-old calves for 101 d. The isolate and the flour provided 56 and 72% of dietary proteins, respectively. Digestibility of feed constituents was measured between 9 to 14 d and 65 to 70 d of treatment. Digestive function was evaluated by measurement of ruminal pH, plasma kinetics of triglyceride and glucose concentrations, and xylose absorption. Antibody production was also recorded. Growth and carcass characteristics were satisfactory for the control diet and the diet based on soy isolate, partly because of high apparent digestibility of protein and lack of antibody synthesis in response to soy isolate. In contrast, protein from soybean flour was poorly digested and highly immunogenic. Ruminal pH at 2.5 h after the meal was unaffected by dietary treatments. Postprandial changes in concentrations of triglycerides and glucose in plasma suggested a lack of abomasal clotting with both diets based on soy. Xylose concentration in plasma was only slightly affected by dietary treatment and calf age. Hydrolyzed soy protein is suitable for veal calves and can account for at least half of protein intake.

Estimation of milk leakage into the rumen of milk-fed calves through an indirect and repeatable method

“…Nevertheless, we found low recoveries of monosaccharides in urine (<25% of intake; Table 2). These values were lower than recovery of D-X in urine from veal calves during the first 6 post-prandial hours only (26% of intake; Lallès et al, 1995). These recoveries question the completeness of digestive absorption and urinary excretion of monosaccharides (Bjarnason et al, 1995).…”

Desempenho de bezerros alimentados usando de sucedâneo até 56 dias de idade

“…Lalles et al (1995) observaram ganhos semelhantes para bezerro, comparando proteínas láctea e de soja, sendo esses superiores aos obtidos no presente trabalho, provavelmente devido à desmama mais tardia. A menor concentração de enzimas proteolíticas no trato gastrointestinal de bezerros e a menor capacidade das enzimas digestivas dos bezerros de hidrolisar proteínas não lácteas têm sido citadas como possível explicação para a menor digestibilidade observada em bezerros alimentados com sucedâ-neo, contendo fontes proteicas não lácteas (Silva et al, 1986).…”

Soybean impairs Na+-dependent glucose absorption and Cl-secretion in porcine small intestine

“…Soybean is widely used in human and animal food because of its high protein content [1][2][3][4]. In animal production, low cost plant proteins are often preferred to more expensive animal protein, especially after the ban on animal products like meat and bone meal or blood meal.…”

“…In animal production, low cost plant proteins are often preferred to more expensive animal protein, especially after the ban on animal products like meat and bone meal or blood meal. Therefore, soybean constitutes a useful substitute for milk proteins in calf and pig nutrition [2,3], and partially or completely replaces fish meal in aquaculture [5]. However, the highest nutritional values of soybean are only obtained when it is highly processed [2][3][4].…”