Preparation Of Probiotics And Its Application In Beef Cattle

The beef cattle production in Xinjiang pastoral areas takes full advantage of natural pastures,and grazing methods are used in summer and autumn.While in spring and winter,the intensive management of rich agricultural crops and farms and byproducts in farming areas is very easy to cause imbalance of the intestinal microflora system,which leads to the body's disorders of digestion,obstructs the growth of beef cattle,and increases the cost of beef production.The previous studies found that the addition of probiotics can improve feed efficiency and increase daily growth performance in beef cattle fattening of high concentrates.Therefore,Bacillus subtilis(BS),Bacillus licheniformis(BL)and Lactobacillus plantarum(LP)are the main strains in this study.Using solid fermentation method,a solid micro-ecological preparation with high viable count and stable quality is developed.The solid microecological preparations are then added to the beef cattle diet to study the effects of the microecological preparations on the growth performance,number of post-intestinal microbiota,serum biochemical indicators and apparent digestibility of the beef cattle,and to provide data support for the wide application of the microecological preparations in beef cattle production.The full text includes two sections.The experiment 1 aims to screen out the best solid fermentation substrate formulation,fermentation conditions,and develop a solid microbial product with high live bacteria and stable quality.The main strains were BS and BL,which are known to produce many enzymes and have strong resistance,and strong acid-producing LP.Bran,corn meal,soybean meal,glucose,gelatin and other carriers were used as fermentation substrates to screen ideal solid state fermentations.The substrate formulation was then subjected to optimization of the fermentation conditions by the single factor test on the best solid fermentation substrate selected above to obtain the optimum fermentation temperature,time and inoculum size.The experiment aims to screen out the best solid fermentation substrate formulation,fermentation conditions,and develop a solid microbial product with high live bacteria and stable quality.The main strains were BS and BL,which are known to produce many enzymes and have strong resistance,and strong acid-producing LP.Bran,corn meal,soybean meal,glucose,gelatin and other carriers were used as fermentation substrates to screen ideal solid state fermentations.The substrate formulation was then subjected to optimization of the fermentation conditions by the single factor test on the best solid fermentation substrate selected above to obtain the optimum fermentation temperature,time and inoculum size.Then,the above-selected optimal solid substrate was precisely weighed,and about 52%of distilled water was added to prepare a certain amount of fermentation products of BS,BL,and LP,and the number of viable cells was detected.The amount of enzyme and the amount of viable cells were determined according to Bacillus.There was a positive correlation between them,so the proportion of viable cells of the fermentation product was(BL:BS:LP=2:2:1)in combination with the solid probiotics used in the test.The results showed that:BS and BL of best solid fermentation substrate formulations:65%wheat bran,15%soybean meal,15%corn flour,2%glucose,3%gelatin;LP of best solid fermentation substrate formula:65%bran,15%soybean meal,14.1%corn flour,2%glucose,3%gelatin,0.3%Na Cl,0.2%CaCO3,0.2%MgSO4,0.2%K2HPO4.The best fermentation conditions were that the BL of fermentation temperature was determined to be 37°C,the inoculation amount was 10%,the fermentation time was 20hours,the live bacteria amount was 5×10~9 CFU/g;BS of fermentation temperature was determined to be37°C,the inoculum amount was 10%,the fermentation time was 22 hours,the live bacteria amount was 5×10~9 CFU/g.The LP of fermentation temperature was 35°C,the inoculum amount was 4%,the fermentation time was 24 hours,and the live bacteria amount was 1×10~9 CFU/g.Under the 30°C drying condition,there was no significant change in the number of viable cells during the 60 d storage period.Experiment 2 aimed to study the effects of probiotics on the growth performance,number of post-intestinal microbiota,serum biochemical parameters and apparent digestibility in beef cattle.A20-month-old,healthy,cross-breeding beef cattle of Kazakh and Yili brown cattle with a healthy body weight of(284±19.33)kg was randomly divided into a control group(CG)and a test group(TG)(10 in each group).The control group(CG)and test group(TG)were fed with Total Mixed Ration(TMR)+Solid substrate of probiotics and TMR+Solid substrate of probiotics+probiotics consisting of Bacillus licheniformis(BL),Bacillus subtilis(BS)and Lactobacillus plantarum(LP)to the diet,respective ratio is(BL:BS:LP=2:2:1).At the time of morning feeding,it is added to the diet alone and fed in a single tank once a day,ensure that the total number of probiotics into each cow fed 5×10~100 CFU/(head·d).The adaption period lasted for 7 days and the formal trial period lasted for 30 days,0 and 30th days were weighed separately.The daily feed intake of each group was recorded.At day 0d,15d,and 30d,fecal samples were collected about 20 cm from the anus,and the number of microbes in the intestine was determined by plate count.In the last 5 days of the formal trial period,feed and fecal samples were collected,and the apparent digestibility of beef cattle was determined by using acid-insoluble ash(AIA)as the endogenous indicator.At the end of the test,5 cows were randomly selected for jugular vein blood sampling only once in each group.The results showed that the ADG and ADFI of the test group were increased by 32.58%and 14.54%(P<0.05),F/G was decreased by 13.58%(P<0.05).With the increase of feeding days,the number of E.coli in the intestine of the experimental group was significantly decreased(P<0.05),while that of Lactobacillus was 2.48%higher than that of the control group(P>0.05).The serum Glucose(GLU)and alkaline phosphatase were higher than the control group.(AKP)and triglyceride(TG)values were 20.4%,21.08%,and 23.53%higher than those in the control group respectively,and blood urea nitrogen(BUN)was decreased by 1%,But all show no significant difference(P>0.05).The apparent digestibility of DM,CP,EE,NDF,and ADF was higher than that of the control group 3.36%,(P<0.05),1.9%(P>0.05),1.49%(P>0.05),4.46%(P>0.05),and 5.11%(P>0.05).In summary,the test results showed that dietary supplementation of a certain amount of probiotics on the growth performance and DM apparent digestibility of beef cattle had a significantly promoting role,significantly reduced the number of post-intestinal E.coli and did not significantly affect the serum biochemical parameters.In conclusion,the solid probiotics developed in this paper have high viable bacteria and stable quality.Supplementation to the diet with 5×10~100 CFU/(head·d)can increase the growth performance and nutrients of beef cattle.The apparent digestibility and the number of post-intestinal E.coli..