Effects of Nutrient Density and exogenous enzymesin Starter Diet on Performance, Intestinal Microflora, Gut Morphology and Immune Response of Broiler Chickens

Effects of exogenous protease on performance, economic evaluation, nutrient digestibility, fecal score, intestinal morphology, blood profile, carcass trait and meat quality in broilers fed normal diets and diets considered with matrix value

This study was conducted to estimate the effects of exogenous protease on performance, economic evaluation, nutrient digestibility, fecal score, intestinal morphology, blood profile, carcass traits, and meat quality in broilers fed normal diets and diets considered with matrix value. A total of 90, one-day-old Arbor Acres broiler chickens were randomly allocated to 3 dietary treatments with 6 replicates and each replicate of 5 broiler chickens. Treatments were as follows: 1) Basal diet (positive control, PC), 2) Basal diet formulated with full ProAct 360 matrix at 50 g/MT without addition of ProAct 360 (negative control, NC), 3) NC + 50 g/MT ProAct 360 (PA). Supplementation of exogenous protease to nutrient deficient NC diet by matrix values (PA) tended to increase growth performance and significantly improved intestinal morphology compared with the NC group. The PA group had significantly lower fecal score, and higher ATTD of crude protein and amino acids than those of the NC group. Furthermore, supplementation of exogenous protease to NC diet decreased feed cost, resulting in improved profit margin. However, there was no significant difference on carcass yield and relative organ weight. In conclusion, supplementation of exogenous protease using matrix value could be used as economic additive to improve growth, profit margin, digestibility, and gut health in broiler chickens.

Effects of Low-Protein Diets and Exogenous Protease on Growth Performance, Carcass Traits, Intestinal Morphology, Cecal Volatile Fatty Acids and Serum Parameters in Broilers

Dietary exogenous proteases (ENZ) can be used in poultry production to improve the growth of chickens fed low-protein (LP) diets. We hypothesized that ENZ supplemented in an LP diet would improve growth performance and physiological response in broilers for 8-35 days. To investigate this, we used a 2 × 2 factorial design with crude protein (CP, normal diet (NP) and LP) and ENZ. The LP diet contained low in 1% CP and ca. 8-12% amino acids compared to the NP diet and both NP and LP diets were added without or with (1 g/kg of diet) ENZ. We randomly allocated 720 1-week-old Ross 308 male chicks to 48 pens and experimental diets. At 21 days, dietary ENZ, but not CP, increased (p = 0.007) live body weight. Body weight gain from 8-21 days was affected (p = 0.006) by dietary ENZ, but was not affected (p = 0.210) by CP. The feed conversion ratio was affected by both CP and ENZ during the starter period (p < 0.05), by ENZ (p = 0.034) during the finisher period, and by CP (p < 0.001) during the whole period. However, the interaction between CP and ENZ did not significantly affect growth performance (p > 0.05). Dietary ENZ increased (p = 0.013) the relative weight of liver at 21 days. CP and ENZ affected (p = 0.043) total short-chain fatty acids at 21 days. However, this effect was not seen (p = 0.888) at 35 days. Dietary CP increased (p < 0.05) the serum concentrations of both uric acid and creatinine in broilers. We concluded that dietary ENZ is more beneficial to younger broilers, independent of CP levels, and that its effect was restricted to body weight and the feed conversion ratio.