Effects of complex enzyme preparation on growth performance,nutrient apparent digestibility,rumen fermentation,immunity,and antioxidant indexes of beef cattle

HONG Min; CHENG Ruibao; LAN Xiangli; SUN Yanan; WANG Hongyu; HAN Xiaohua; SUN Yingwu; LIU Zhiyou

doi:10.13557/j.cnki.issn1002-2813.2025.14.005

Abstract：This experiment aimed to investigate the effects of complex enzyme preparation on the growth performance,nutrient apparent digestibility,rumen fermentation,immunity,and antioxidant indexes of beef cattle.A total of 20 Simmental cattle with an initial body weight of(398.00±8.50)kg were randomly divided into two groups,with 10 replicates per group and one beef cattle per replicate.The control group was fed a basal diet,while the experimental group was fed a basal diet supplemented with 1.0 kg/t complex enzyme preparation.The pre-test period was 10 days,and the formal test period was 60 days.The results showed that compared with the control group,the average daily weight gain of beef cattle in the experimental group was significantly increased(P＜0.05),and the feed to gain ratio was significantly decreased(P＜0.05).The apparent digestibility of crude protein(CP)and crude fat(EE)in the experimental group were extremely higher than that in the control group(P＜0.01),the apparent digestibility of acid detergent fiber(ADF)was significantly higher than that in the control group(P＜0.05).The content of ammonia nitrogen in the rumen fluid of the experimental group was lower than that of the control group(P＜0.05),while the concentrations of acetic acid and microbial protein were higher than those of the control group(P＜0.05).On the 30th and 60th days of the experiment,the concentrations of total protein(TP)and high-density lipoprotein(HDL)in the serum of beef cattle in the experimental group and the activity of superoxide dismutase(SOD)were significantly higher than those in the control group(P＜0.05).The activity of aspartate aminotransferase(AST)and the concentrations of triglycerides(TG),total cholesterol(TC),and interleukin-1β(IL-1β)were significantly lower than those in the control group(P＜0.05).On the 30th day of the experiment,the content of low-density lipoprotein(LDL)in the serum of beef cattle in the experimental group was extremely higher than that in the control group(P＜0.0l).On the 60th day of the experiment,the content of serum immunoglobulin G(IgG)and total antioxidant capacity(T-AOC)in the experimental group were extremely higher than those in the control group(P＜0.01),and the content of malondialdehyde(MDA)was significantly lower than that in the control group(P＜0.05).The study indicates that adding 1.0 kg/t of the complex enzyme preparation to the feed can increase the nutrient apparent digestibility,optimize the rumen fermentation parameters,improve the growth performance of beef cattle,enhance the lipid metabolism status,and strengthen the immune function of beef cattle.