Effects And Correlative Research Of Daidzein On Production Performance, Blood Index And Fecal Microfolar In Growing Jinjiang Cattle

Daidzein, a type of green feed additive of phytoestrogen has many physiological functions. In this paper, the effects of daidzein on growth performance, nutrient digestibility, blood index and fecal microbial community structure of growing jinjiang cattle were studied, which will provide a theoretical basis for daidzein applied to calf production. The following aspects were studied:Experiment 1: The effects of daidzein on growth performance, nutrient digestibility and relative blood parameters of the growing jinjiang cattle were studied. Twenty healthy,similar weight(140±5)kg and about six months jinjiang cattle were randomly and equally divided into four groups. Three experimental groups were fed the basal diet and supplemented with 100,200,400 mg/kg daidzein,respectively. The control group was fed the basal diet. The pre-feeding period was 10 days and the formal stage was 60 days. The results showed that:(1) Compared with the control group, the average body weight of calves among different level daidzein added groups significantly improved(P<0.05), and the average daily gain from a low dose to a high dose of daidzein in treatment groups increased by 19.05%, 21.05% and 29.19%,respectively. The average daily gain in 400mg/kg daidzein added group was significantly higher than 100 mg/kg group(P<0.05), but there were no significantly difference between 200 mg/kg group and the other two level daidzein added groups(P>0.05).(2) The apparent digestibility of crude protein in each different level daidzein added group was significantly higher than the control group(P<0.05), and the digestibility of NDF in 100 mg/kg group decreased at a certain degree compared with the control group(0.05?P?0.1).(3) The daidzein treatment group had the effects on decreasing the content of blood glucose levels, especially significantly reducing blood sugar concentrations at day 60(P<0.05). These results indicate that daidzein can improve the growth performance of calves, increasing growing jinjiang cattle crude protein digestibility and reducing the blood glucose concentrations, and the overall effects of 400mg/kg group were better.Experiment 2: The effects of daidzein on blood antioxidant capacity, immune function and endogenous hormones of growing jinjiang cattle were studied. The experimental design and animals were the same as experiment one. The results displayed that:(1)Compared with control group, the T-SOD and GSH-Px concentrations of samples obtained at day 30 and 60 increased in a certain degree, while MDA serum concentrations decreased(P>0.05). At the end of the experiment(60d), the T-SOD of each different level daidzein added group was significantly higher than the control group(P<0.05), but the differences between different level daidzein added groups were not significant(P>0.05). Meanwhile,diet with daidzein had the trend to increase serum GSH-Px activities(0.05?P?0.1).(2) The immunoglobulins of different level daidzein added groups increased compared with thecontrol group. The determination results of 30 d serum samples showed that the content of IgG of 400 mg/kg group was significantly higher than control group(P<0.05). 60 d measurement results showed that the concentration of 200 mg/kg and 400 mg/kg daidzein addded groups of IgM were significantly higher than that of the control group(P<0.01),meanwhile 100 mg/kg daidzein added group of immunoglobulin IgM concentration was higher than the control group but there was no significant difference(P>0.05).(3)Basic diet with daidzein could improve blood endogenous hormones at a certain degree. At day 30, the content of blood T3 levels of each different level daidzein added group was significantly lower than the control group(P<0.05), and the content of blood T4 levels had also the trend of decrease compared with the control group. The levels of testosterone in200 mg/kg group were significantly higher than that in the control group(P<0.05).However, the testosterone levels in the other two level daidzein added groups were also higher than those in the control group, though the difference was not significant(P>0.05),and there were also no significant difference between the different level daidzein added groups(P>0.05). At day 60, the concentrations of T3 of 400 mg/kg daidzein added group was significantly higher than that of 100mg/kg group(P<0.05), but there were no significant differences between each different level daidzein added group and control group(P>0.05). The concentrations of blood GH and IGF-1 of the 400 mg/kg daidzein added group were significant higher than that of the control group and the other two treatment groups(P<0.05). Additionally, there were no significant differences among the control group, the 100 mg/kg, 200 mg/kg groups(P>0.05). These results suggest that:Basal diet supplement with approporiate Daidzein may increase antioxidant and immune performance of calves, meanwhile improve the levels of serum endogenous hormones.Experiment 3: This experiment was aimed at studying the effects of daidzein on fecal bacterial diversity and structure of calves. Three healthy and similar body weight growing jinjiang cattle from each group were chosen. The experimental design was the same as experiment 1. At the last three days of the trial period, the fecal samples were collected from each calf used for deteriming of bacterial flora. The diversities and structures of fecal microflora were determined by Miseq high throughput sequencing technology. The results showed that:(1) According to the composition of bacteria phylum level, compared with the control group, the abundance of Firmicutes of 200 mg/kg and 400 mg/kg groups had a increasing trend(0.05?P?0.1), while the abundance of bacteroidetes was lower. Basic diet with daidzein increased Proteobacteria abundance to some extent, but the proportion of Spirochaetae and Saccharibacteria decreased at a certain degree compared with the control group.(2) According to the composition of bacteria family level, The proportion of Ruminococcaceae of 400mg/kg daidzien added group was significantly higher than100mg/kg group(P<0.05), but there were no significant differences between each different level daizein added group and control group(P>0.05); compared with the control group, the abundance of Peptococcaceae was increased in a certain degree in each dadzein added group(P>0.05), and the abundance of Peptococcaceae from a low dose to a highdose of daidzein in treatment groups increased by 21.43%,142.86% and 50%,respectively;the proportion of Coriobacteriaceae in 100 mg/kg and 200 mg/kg daidzein added group were lower than the control group, but there were no significant differences compared with the control group(P>0.05); meanwhile, the abundance of Porphyromonadaceae in 100mg/kg and 400 mg/kg daidzein added group were lower than the control group, there were no significant difference between two daidzein added group and control group(P>0.05).(3)According to the composition of bacteria genus level, the percentage of Ruminococcaceae_UCG-005 of 100 mg/kg group had a decreasing trend(0.05?P?0.1),and the abundance of Lachnospiraceae_NK4A136_group and Phocaeicola of 200mg/kg group were significant higher than that of the control group. Compared with the control group, the abundance of Ruminococcaceae_UCG-010 and Succinivibrio increased, but Ruminococcaceae_UCG-014 reduced at a certain degree, respectively(P>0.05). These results showed that the total numbers and diversities of the fecal bacteria of calves can not be significantly influenced by daidzein, but the composition of bacteria in fecal can be altered, which will be helpful to reduce the colonization of harmful bacteria and the inflammation of animals.