A newly developed tannase enzyme from Aspergillus terreus versus commercial tannase in the diet of lactating Damascus goats fed diet containing pomegranate peel

Abstract

Inclusion of tannase enzyme in tannin-rich diets of lactating animals can be explored as a strategy to overcome the negative effects of tannins on feed utilization and lactational performance. The present study aimed to compare the effect of replacing commercially available exogenous tannase with a newly developed tannase, produced from Aspergillus terreus, on feed utilization and lactational performance of lactating Damascus goats fed tannin-rich pomegranate peel based diet. Thirty lactating Damascus goats were randomly stratified into 3 treatments and fed pomegranate peel-based basal diet at 10% (containing 7.13% tannins DM basis) without exogenous tannase as a control treatment or with addition of 500 IU of new tannase/kg feed daily, or 500 IU of commercial tannase/kg feed daily for 9 weeks. Tannases decreased feed intake and increased diet digestibility; however, new tannase increased (P<0.05) diet digestibility relative to commercial tannase. Tannase treatments increased (P<0.05) blood total protein and glucose concentrations. New tannase improved (P<0.05) milk production and feed efficiency, without affecting milk composition. Moreover, new tannase reduced (P<0.05) total unsaturated fatty acids (UFA) and increased (P<0.05) poly UFA and total conjugated linoleic acid concentrations, while the commercial tannase increased (P<0.05) total SFA and atherogenic index. Tannases reduced (P<0.05) milk total essential amino acids (EAA), total non-EAA, total conditionally EAA, and total branched amino acids. It is concluded that tannases enhanced the utilization of tannin-rich diet by lactating goats, with better results for the new tannase produced from A. terreus compared with the commercial tannase.