Effects Of Complex Microecological Preparations On Rumen Fermentation,Performance,Blood Indexes And Rumen Function Of Dairy Goats In Vitro

Compound microecologics are biological feed additives prepared by a variety of beneficial microorganisms,which play an important role in ruminant production.Based on the current research status of compound microecologics at home and abroad,this study explored their effects on performance,blood biochemistry and rumen function of lactating sheep through in vitro fermentation and animal feeding experiments.To provide the theory and application basis in breeding production.This study is divided into two parts.Treat 1:Effects of complex microecological preparations on rumen fermentation characteristics of dairy goats in vitroRumen fluid donor animals were selected adult Sarone dairy goats fitted with permanent rumen fistulas.The fermentation substrate ratio was50:50.The fermentation substrate of control group was silage corn,soybean meal and bran,and the fermentation substrate of experimental group was added with 0.40% microecological preparation on the basis of control group.Anaerobic fermentation was performed at 4,12,24 and 48 h using an automatic in vitro simulated rumen fermentation device,with 3 parallel and 3repeated experiments in each group.The results show that: Compared with the control group,dry matter degradation rate at 24 h was significantly increased by 6.98%(P < 0.01),total gas production at 24 h was significantly increased by 15.03%(P < 0.05),and methane production at 48 h was significantlydecreased by 8.51%(P < 0.05).There was no significant difference in hydrogen production between the two groups(P > 0.05).In vitro rumen fermentation parameters of the two groups,p H value and microbial protein had no significant effects(P > 0.05),ammonia nitrogen at 12 h was significantly increased by 16.11%(P < 0.05),and volatile fatty acids at 4 h,isobutyric acid and valeric acid in experimental groups were significantly decreased(P =0.098)and(P = 0.088).There were no significant differences in total volatile acid,acetic acid,propionic acid,butyric acid and the ratio of ethylene to propylene(P > 0.05).In conclusion,the composite microecological preparation can improve the dry matter degradation rate,effectively reduce the production of CH4,thus reducing greenhouse gas emissions,more conducive to rumen health,conducive to the sustainable development of modern animal husbandry environment.Treat 2: Effects of compound microecological preparations on rumen fermentation characteristics in vitro at different time points of dairy goatsA total of 26 lactating Sarone dairy goats with(1 to 2)parity and(1.01±0.38 kg/d)average daily milk yield were randomly divided into 2groups with 13 goats in each group.Goats in the control group were fed a basal diet,and goats in the experimental group were fed the control diet supplemented with 10 g/d microecological preparation.The effective viable numbers of Lactobacillus casei and Saccharomyces cerevisiae were ≥ 1.0×108CFU/g and 0.2×108 CFU/g.The experimental pre-feeding period lasted for 7days and the experimental period lasted for 36 days.The results showed as follows: 1.In terms of production performance,there were no significant differences in dry matter intake,milk yield and feed to milk ratio between the two groups(P > 0.05);In terms of milk composition,milk protein of experimental group had a significant increase trend on the 21 st and 43 rd days(P = 0.094)and(P = 0.069),while non-fat solids had a significant increase trend on the 21 st and 43 rd days(P = 0.082)and(P = 0.070).There were no significant differences in other milk components between the two groups(P >0.05).There was no significant difference in apparent digestibility between the two groups(P > 0.05).2.In terms of blood indexes,blood biochemical glucose in test group was significantly increased by 39.83% compared withcontrol group(P < 0.05),while total protein,albumin,globulin and other indexes were not significantly different(P > 0.05);In terms of serum immune indexes,the immunoglobulin Ig A content in experimental groups was significantly increased by 25.06%(P < 0.01),but there was no significant difference between immunoglobulin Ig G and immunoglobulin Ig M(P > 0.05).The contents of interleukin-1 and interleukin-6 were significantly decreased by33.23% and 15.80%(P < 0.01).In terms of serum antioxidant indices,the content of propylene glycol was significantly decreased by 16.16%(P < 0.05),the content of superoxide dismutase was significantly increased by 35.01%(P< 0.01),and the content of glutathione peroxidase was significantly increased by 13.11%(P < 0.05).There was no significant difference in total antioxidant capacity between the two groups(P > 0.05).3.In terms of rumen fermentation parameters,there were no significant differences in p H,microbial protein and ammonia nitrogen between the two groups(P > 0.05).The proportion of butyric acid in experimental groups was significantly decreased(P = 0.070),the proportion of valerate was significantly decreased by 14.14%(P < 0.01),and the ratio of acetic acid,propionic acid and ethylene to propylene was not significantly different(P > 0.05).At the level of rumen bacteria,the relative abundance of Fibrobacteres of the experimental group was significantly increased by 123.08%(P < 0.05),and the relative abundance of Lactobacillus SR1 tended to increase(P = 0.072).At the family level,the relative abundance of Paraprevotellaceae in experimental group tended to increase(P = 0.099)At the genus level,the relative abundance of Ruminococcus and Oscillospira showed an increasing trend(P = 0.072)and(P = 0.072).In conclusion,composite microecological preparations can promote the health of ruminants,improve production performance,improve rumen fermentation parameters,and optimize rumen microbial community structure by increasing the content of immunoglobulin and antioxidant properties of the body.Therefore,the development and utilization of composite microecological preparations as feed additives for ruminants have broad application prospects.