Influence of strain of chickens on ileal amino acids digestibility of different protein sources

The main objective of this study was to assess the nutritional value of four protein sources (soyabean meal, fish silage, sardine fish and fishmeal) using commercial broiler and local poultry strains. Four experimental diets were formulated; representing four different proteins sources and was evaluated using six replicates of eight birds per cage at 21 day of age. Cages were located in an environmentally controlled room maintained under conditions suitable for birds at this age with a photo-period of 23 h in every 24 h. Diets and water were offered on ad libitum basis. On the fourth day after the adaptation to the experimental diets, feed troughs were removed from every cage for 1 h and then reintroduced for 2 h. Then the birds were killed to allow for sampling of ileal digesta, from Meckel's diverticulum to the ileal-caecal-colonic injunction. Broiler birds showed significantly (p<0.001) higher digestibility coefficients and digestible content of amino acids across all the protein sources than the local birds. Out of the four protein sources evaluated in this study, fishmeal had the lowest amino acids digestibility coefficient for the two bird breeds (p<0.001). The digestibility coefficient and digestible content of amino acids estimates for fish silage was the highest across the two strains (p<0.001). The lower digestibility of amino acids for soyabean meal is related to the presence of; antinutritional factor, trypsin inhibitor. Fish silage shows a great potential to be used as protein supplements for poultry feeding. The results suggest that the class of chickens and protein source significantly influenced the apparent ileal digestibility and digestible contents of amino acids in the nutrient assessed in this study.