Effects of fermented Chinese herb residues on growth performance, nutrient apparent digestibility, serum biochemical indices and faecal microbial flora in beef cattle

This study aimed to evaluate the effects of fermented Chinese herb residues on the growth performance, nutrient apparent digestibility, serum biochemical indices and microflora of Simmental beef cattle during the fattening period. Twenty-four healthy Simmental beef cattle with an average body weight of 358.54 ± 65.63 kg were randomly divided into four treatment groups, with 6 replicates. The dietary treatments were as follows: I: basal diet; II, III and IV: 10% corn husk in the diet was replaced by Chinese herb residue, enzyme-fermented residue, and enzyme bacteria co-fermented residue, respectively. The experimental period was 49 days. There was no significant difference in the growth performance of beef cattle (p > 0.05). The ether extract (EE) apparent digestibility of groups III and IV was significantly higher than that of group I (p < 0.05); the apparent digestibility values of nitrogen free extract (NFE) and total phosphorus (P) in group IV were significantly lower than those in the other groups (p < 0.05). The maleic dialdehyde (MDA) contents in groups I and II were significantly higher than those in groups III and IV (p < 0.05). The ACE and Chao1 indices of groups I and III were significantly higher than those of groups II and IV (p < 0.05). The Shannon indices of groups I and III were significantly higher than that of group II (p < 0.05). The abundance of Firmicutes in group III was significantly lower than that in group II (p < 0.05). In conclusion, fermented Chinese herb residues could replace 10% corn husk and be used in beef cattle breeding.