EXOCRINE FUNCTION OF THE PANCREAS IN LAYING HENS FED DIETS SUPPLEMENTED WITH SYNTHETIC AMINO ACIDS

УДК: 636.52.58: 612.343: 636.084.7 DOI: 10.31588/2413_4201_1883_2_266_69

Authors

  • Victoriya Vasilevna Lopatina Russian State Agrarian University -- Moscow Agricultural Academy named after K.A. Timiryazev

Keywords:

laying hens, pancreas, exocrine function, low-protein diet, synthetic amino acids, trypsin

Abstract

The aim of this study was to evaluate the effect of a low-protein diet balanced with synthetic limiting amino acids on exocrine pancreatic function in laying hens. The study was conducted on Hisex White laying hens aged 40 weeks and older with chronic duodenal fistulas. Each group consisted of six birds. The control group received a complete feed, while the experimental group received an experimental low-protein wheat-based diet balanced with synthetic amino acids. Duodenal chyme samples were collected on an empty stomach, as well as 1 and 2 hours after feeding. One hour after feeding, trypsin activity in the duodenal chyme of laying hens in the experimental group exceeded the control group by 38.2% (p<0.05). No significant intergroup differences were found in the fasting state or 2 hours after feeding. After feeding, an increase in trypsin activity was observed in the duodenal chyme of laying hens of both groups compared to the initial level, but after 2 hours, a decrease was observed in the chyme of birds in the experimental group compared to 1 hour after feeding. Blood morphological parameters did not differ between the control and experimental groups. Biochemical analysis of blood of birds in the experimental group revealed an increase in alkaline phosphatase activity, a decrease in the level of triglycerides and ionized calcium (p<0.05). The obtained results show that the use of a low-protein diet balanced with synthetic amino acids alters the dynamics of postprandial enzymatic activity of the pancreas and reflects the adaptation of the digestive system to the altered amino acid profile of the diet.

Author Biography

Victoriya Vasilevna Lopatina , Russian State Agrarian University -- Moscow Agricultural Academy named after K.A. Timiryazev

Post-graduate student, Assistant of Animal Physiology, Ethology and Biochemistry Department

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Xing R, Fan K, Fan Z. Porcine bile acids improve performance by altering hepatic lipid metabolism and amino acid metabolism with different protein level diets in late laying hens. Poultry Science. 2025; Vol.104. Article 104777. https://doi.org/10.1016/j.psj.2025.104777

Ravindran V, Abdollahi MR. Nutrition and digestive physiology of the broiler chick: state of the art and outlook. Animals. 2021; Vol.11. 10. Article 2795. https://doi.org/10.3390/ani11102795

Published

2026-09-03