摘要：Two experiments were carried out to evaluate the effects of laboratory produced tannase enzyme (Tanozym) to diet including Palm Kernel Powder (PKP) on in vitro dry matter and organic matter disappearance (IVDMD and IVOMD) and in vivo nutrients digestibility, nutritive value s, milk production and composition by lactating Baladi goats. In vitro experiment, IVDMD and IVOMD, were determined for control diets (60% CFM and 40% Berseem hay); (T1) control diet plus different levels of polyethylene glycol (PEG), being 10, 15 and 20 g kg-1 DM and (T2) control diet plus different levels of Tanozym (3.9, 5.85 and 7.8 U kg-1 DM). The maximum IVDMD and IVOMD values were observed with 5.85 U kg-1 DM for Tanozym and 20 g kg-1 DM for PEG compared to control, however there was no significant (p<0.05) difference between 15 and 20 g kg-1 DM. The in vivo experiment was carried out on nine lactating Baladi goats after 7 days of parturition where animals were divided into three groups, three animals each, using 3x3 Latin square design. The first group fed control diet (60% CFM and 40% Berseem hay), the second group fed T1 (control diet plus 15 g kg-1, DM), the third group fed T2 (control diet plus 5.85 U kg-1, DM). Tanozym supplementation significantly (p<0.05) increased nutrients digestibility, nutritive value s, ruminal Total Volatile Fatty Acids (TVFAs) but insignificant (p<0.05) increased ammonia nitrogen (NH3 N). Lower significant (p<0.05) values of rumen pH were recorded for treated groups compared with the control. Blood serum of animals fed Tanozym and PEG had higher values of total protein, albumin, globulin, total lipids, urea and glucose but lower values of AST and ALT compared with those of control. Daily milk yield, SNF, lactose and ash yield were significantly (p<0.05) increased with Tanozym compared control group. While, there are no significant (p>0.05) differences among groups for fat corrected milk 4%, total solids, fat and total protein yield.
