Trypsin activity in duodenal contents of broiler chickens as an indicator of adaptation to diet composition

Relevance. The use of non-traditional dietary components in poultry farming is associated with the industry›s need for new additives that could compete in price and quality with soy products and animal feeds. Their use should be based on a comprehensive study of their chemical composition and physiological properties. Methods. The most objective way of evaluation is the determination of taste and nutritive value on fistulated birds by the activity of digestive enzymes after 60 and 120 minutes from the moment of feeding when using the studied additives in the diet. Results. Experiments performed on broiler chickens showed that out of three additives (soybean meal, rape seeds and white lupine) the most preference was given to white lupine by experimental fistula chickens, because in this case there was a more pronounced reaction from the side of trypsin activity in comparison with the control feed (trypsin activity was higher by 29,0% (p < 0.05) in the first 60 minutes after feeding. In this case, the lowest indices of phosphatase-trypsin index and increase of protein metabolism by blood biochemical indices were noted. When using rape seeds in the feed mixture, a tendency of trypsin activity decrease in the first 60 minutes after feeding was observed, indicating lower palatability of this additive.