Effects of potato peels inclusion with exogenous enzymes in broiler diet on growth performance, nutrients digestibility and carcass characteristics

The purpose of the research was to investigate the effects of including potato peels (PP) in broilers diet with exogenous enzymes supplementation on feed intake (FI), body weight gain (BWG), nutrient digestibility and carcass parameters. For this purpose, five iso-caloric and iso-nitrogenous rations were formulated with different levels of PP (0, 5, 10, 15 and 20%). Experimental diets were supplemented with a blend of exogenous enzymes (Xylanase, Mannanase, Protease, Cellulase). A total of four hundred male broiler chicks (day old) of 38 ± 3 gram were randomly distributed into 5 experimental groups in such a way that each group had 8 replicates and each replicate had 10 birds. Results revealed that the inclusion of PP @ 5% with exogenous enzymes had similar FI, BWG and nutrients digestibility with control. However, the inclusion of P @ of 10, 15, and 20% with exogenous enzymes in the broiler diet adversely affected the BWG, feed conversion ratio and nutrient digestibility (p < 0.05). Results of carcass parameters were not affected (p > 0.05) by dietary treatments. Based on findings, it is concluded that 5% addition of PP with exogenous enzymes could be practiced in broiler diet without any adverse effect on the performance of commercial broilers.

Digestive Ability, Physiological Characteristics, and Rumen Bacterial Community of Holstein Finishing Steers in Response to Three Nutrient Density Diets as Fattening Phases Advanced

The aim of this study is to track the dynamic alterations in nutrient intake and digestion, rumen fermentation and plasma metabolic characteristics, and rumen bacterial community of Holstein finishing steers in response to three nutrient density diets as fattening phases advanced. A total of eighteen Holstein steers were randomly allocated into three nutrient density groups and steers in each group were fed under a three-phase fattening strategy, with nutrient density increased in each group when fattening phase advanced. Results showed that both fattening phase and dietary nutrient density significantly influenced the nutrient digestion, most of the rumen fermentation parameters, and part of bacteria at phylum and genus levels. Individually, dietary nutrient density affected the concentrations of plasma alanine aminotransferase and urea N, bacterial richness and evenness. All determined nutrient intake and plasma biochemical parameters, except for alanine aminotransferase and triglyceride, differed among fattening phases. Spearman correlation analysis revealed strong correlations between fiber intake and bacterial richness and evenness, rumen fermentation characteristics and certain bacteria. Moreover, Patescibacteria abundance was positively correlated with ambient temperature and plasma total protein. These results indicate that rumen fermentation and nutrient digestion were influenced by both dietary nutrient density and fattening phase, and these influences were regulated by certain rumen bacterial community and ruminal bacteria may be affected simultaneously by ambient temperature. This study may provide insights into diet optimization and potentially adaptive mechanism of rumen bacterial community in response to fattening phases and gradually climatic change.