Comparison of the Kinetics of Pancreatic Secretion and Gut Regulatory Peptides in the Plasma of Preruminant Calves Fed Milk or Soybean Protein

Abstract

Exocrine secretion from the pancreas and concentrations of cholecystokinin, gastrin, secretin, and somatostatin in plasma were measured in relation to feeding in 70- to 120-d-old preruminant calves fed either a milk diet or a soybean diet. Pancreatic fluid was continuously collected, measured, and reintroduced in catheterized calves. Blood samples were withdrawn for measurements of gut regulatory peptide concentrations in plasma. A slight increase in outflow of pancreatic fluid was observed 30 min before the milk diet was introduced but not before the soybean diet was fed. In contrast, concentrations and outflows of protein and trypsin immediately after feeding were higher when calves were fed the soybean diet. Overall, during the first 5 h postfeeding, the outflow of pancreatic fluid was 40% higher when the milk diet was fed than when the soybean diet was fed. No difference in outflow of protein was observed, but that of trypsin was 82% higher when the soybean diet was fed. This enhanced enzyme secretion could have been related to the increased plasma concentrations of gastrin and cholecystokinin after the soybean diet was fed. Secretin release was less in calves fed the milk diet that in calves fed the soybean diet during the first 2 h postfeeding, suggesting that this gut peptide along with gastrin and cholecystokinin, contributed to the stimulation of enzyme secretion. Plasma gut regulatory peptides could be influenced by the soybean diet, which does not coagulate in the stomach, inducing faster gastric emptying of protein and fat, and by the chemical form of protein from the soybean diet and the lower susceptibility of these proteins to protease compared with casein. However, the resulting enhancement of pancreatic trypsin secretion and activity seemed to be insufficient to increase the digestibility of soybean protein up to a level similar to that of milk.

Morphology and enzyme activities of the small intestine are modulated by dietary protein source in the preruminant calf

“…Gastrin and perhaps CCK are important for mucosal growth of the small intestines but the actual mechanisms are not completely understood [13]. Le Dr6an et al [19] [12]. Alkaline phosphatase activity was also lower with lactalbumin, egg albumin, zein, gelatin or wheat gluten than with the phosphoproteins casein and vitellin [36].…”

“…Highly antigenic products, such as heated soybean flour, presented the lowest digestibility, which could be partially explained by an increased flow of undigested globulins in the ileum [37]. The intrinsic resistance of legume seed protein to digestion [23] [19]. The (3-conglycinin appears to be the most allergenic [19].…”

“…The intrinsic resistance of legume seed protein to digestion [23] [19]. The (3-conglycinin appears to be the most allergenic [19]. As a consequence, villus atrophy and increased densities of T and B lymphocytes in the mucosa can be observed [18].…”

Effects of Hydrolyzed Spray Dried Red Blood Cells in Milk Replacer on Calf Intake, Body Weight Gain, and Efficiency

“…Furthermore, availability of edible-grade milk proteins may decline in the future as use of these proteins in human foods increases. Alternative protein ingredients, including soy (15,17,28), wheat protein (3,27), fish protein (7,8,13), and potato protein (3), have been evaluated and incorporated into some CMR.…”

Desempenho de bezerros alimentados com dietas líquidas à base de leite integral ou soro de leite

“…Uma terceira hipótese sugere que, embora a maioria das alterações nas concentrações plasmáticas dos hormônios sofra influência principal da idade e do desaleitamento, o aumento na velocidade de passagem da digesta para o intestino delgado também pode modificar o padrão normal de secreção de hormônios metabólicos e gastrintestinais, alterando o desenvolvimento funcional e os processos digestivos e absortivos (Le Drean et al, 1998). A chegada de grande quantidade de aminoácidos e gorduras ao intestino delgado pode gerar, por exemplo, um pico de somatostatina, resultando em inibição da secreção de hormônios e enzimas gastrintestinais e pancreáticas.…”