Growth performance, internal organ traits, intestinal morphology, and microbial population of broiler chickens fed quinoa seed-based diets with phytase or protease supplements and their combination

The aim of this study was to evaluate the effects of quinoa seed-based diets with phytase and protease enzymes, individually or in combination, on the productive performance, internal organs, microbiota activity, and intestinal morphology of broiler chickens. A total of 250 1-day-old broiler chicks (ROSS 308) were randomly distributed into five treatments with each five replicate pens of 10 birds in a 42-day trial. Dietary treatments were a conventional diet (CC) based on a corn-soybean meal or an experimental diet (EC) which contained 150 g/kg of quinoa seed. Other treatments were EC diet supplemented with 500 FTU/kg phytase (EPH), 0.2 g/kg protease (EPR) enzymes, or their combination (EPPC). At the end of the trial, the feed intake of the EPH broilers was higher than those of the EC and EPPC birds (P < 0.05). Meanwhile, broiler chickens fed the EPH and EPPC diets had higher body weight gain compared with those of the birds fed the other diets (P < 0.05). The EC and EPPC broilers consumed less feed than the EPH birds (P < 0.05), while CC and EPR birds were intermediate. The EC group had the highest feed conversion ratio among all groups (P < 0.05). The EPPC group had the best feed conversion ratio compared with other groups except for the EPH group (P < 0.05). The highest relative weight of the bursa and spleen was observed in EPPC and CC groups, respectively. The pancreas had the lowest weight in the broilers fed protease-supplemented diet. An increase in villus length and villus width was observed in birds fed EPH and EC diets, respectively (P < 0.05). The ratio of VL to crypt depth was greater in the phytase-supplemented group (P < 0.05). Inclusion of phytase or phytase + protease to QS diet increased the cecal Lactobacillus population, while the count of Coliforms decreased in EPR and EPPC groups (P < 0.05). It is concluded that addition of phytase and protease enzymes to QS-based diet may have beneficial effects on the growth performance, gut bacteria ecology, and intestinal morphology of broiler chickens.