TITLE:
On the Activities of Pancreatic Proteases and Alpha-1 Proteinase Inhibitor in Meat-Type Chicken
AUTHORS:
Vladimir G. Vertiprakhov, Alena A. Grozina, Ivan A. Egorov, Tatiana N. Lenkova, Vardges A. Manukyan, Tatiana A. Egorova
KEYWORDS:
Chicks, Pancreas, Trypsin, Alpha-1 Proteinase Inhibitor (Antitrypsin), Serum, Duodenal Fluid
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.7 No.3,
July
12,
2017
ABSTRACT: The study was aimed at the evaluation of the effects
of breed, age, different digestion stimulators, and dietary crude protein (CP)
level on the activities of proteolytic enzymes in pancreatic tissue and
duodenal chymus (in vivo), serum
trypsin and α1-proteinase
inhibitor (A1PI) concentrations in meat-type chicks. The study of age dynamics
of trypsin and A1PI concentrations was performed on the chicks of hybrid cross
“Smena-8”and two parental lines (Plymouth Rock and Cornish) fed standard commercial corn-wheat-SBM
diets. Twenty birds per breed were euthanized at 1, 7, 14, 21, 28 and 35 days
of age to obtain blood samples and pancreatic homogenate. Experiments on the
effects of different digestion promotors (probiotic, acidifier, phytobiotic,
enzymatic preparation) and different CP levels (finisher diet, CP 20%, vs.
ground corn, CP 8.5%) were performed on 12 hybrid chicks with fistulated duodenum from 14 to 50 days of age. The following conclusions were made: 1) At 1 day of age high
proteolytic activity in pancreatic tissue and maximal serum concentrations of
trypsin and A1PI were found in both hybrid and parental lines. Since 7 to 35
days of age A1PI concentration was nearly constant, serum trypsin concentration decreased while
proteolytic activity in pancreatic tissue exhibited undulate increase; 2) Proteolytic activity in pancreatic tissue was
higher in hybrids compared to the parental lines from 7 to 35 days of age (p 0.05); 3) Supplementation of diet with exogenous enzymes
stimulated the digestion due to the increase in protease activity in duodenal
chymus by 9.1% compared to unsupplemented control (p 0.05); 4) Proteolytic activity in duodenal chymus
significantly responded to the substitution of ground corn for the complete
diet by 2-fold decrease while serum trypsin concentration responded by 2.5-fold
increase (p 0.001). This fact can
indicate that physiological functions of digestive proteases are not confined
to the digestive processes.