| In response to the current problem of antibiotic abuse in the farming industry,antibiotics in feed have been completely banned,and animal performance has dropped significantly,while the mortality rate due to disease has gradually increased,and the level of farming and other related agricultural production has been very seriously affected.With the increase in the dose of veterinary antimicrobial drugs and the increasing resistance,more and more residues of veterinary drugs in the product,seriously endangering human health and food safety.In order to strengthen the comprehensive management of veterinary antimicrobial drugs,as well as effectively curb the resistance of animal-derived bacteria,eliminate a series of problems such as excessive residues of veterinary drugs in products,and comprehensively improve the level of green and healthy breeding of livestock and poultry in China,in October 2021 by China’s Ministry of Agriculture and Rural Development to develop and implement the action plan to reduce the use of veterinary antimicrobial drugs,research and development of safe,efficient and ecologically sound new veterinary antibiotics It is urgent to develop new safe,efficient and ecologically sound alternatives to veterinary antibiotics.The combination of the two can play a synergistic effect,which can improve the intestinal flora of animals on the one hand,and enhance the immunity of the body to promote growth on the other.However,the sources of probiotics and the selection of Chinese medicine,the fermentation conditions for the preparation of the two compound preparations,and the effectiveness of the two compound applications still need to be further explored and studied.In this experiment,we intend to conduct tolerance test(heat,acid and bile salt resistance)and mutual inhibition test of probiotics with several strains of lactic acid bacteria and bacillus preserved in the laboratory,and screen out probiotics with good tolerance to heat,acid and bile salt,as well as those that do not inhibit each other as fermentation strains;then conduct the inhibition test of probiotics with Chinese medicine,screen out Chinese medicine that does not inhibit probiotics as fermentation substrate,and use probiotics to fermentation substrate A single-factor test was conducted to optimize the fermentation time,inoculum amount and temperature of the fermentation broth,and the polysaccharide and flavonoid contents in the herbal medicine-probiotic combination were used as response values to optimize the best fermentation conditions by using response surface test design to prepare a herbal medicine-probiotic compound preparation useful for animal husbandry.1.Screening of optimal Lactobacillus and Bacillus for swine and their combination with traditional Chinese medicineIn this experiment,40 strains of Lactobacillus and Bacillus isolated from feces frozen in the laboratory were recovered and identified,and the strains were tested for heat,acid and bile salt tolerance,from which two strains of Lactobacillus FC1 and SQ9 and two strains of Bacillus Y4 and Y2 with good tolerance were selected.The four herbal medicines,Taraxacum mongolicum,Houttuyniae Herba,Ligustrum lucidum and Codonopsis pilosula,had no inhibitory effect on the two strains of probiotics screened and could be used in the follow-up experiments.2.Preparation of herbal-probiotic compound preparation for swineIn this experiment,the fermentation time,inoculum amount and fermentation temperature were identified as the key influencing factors through one-way ANOVA,based on which the response surface test design was carried out by optimizing the fermentation time,inoculum amount and temperature,with the polysaccharide and flavonoid contents in the herbal-probiotic combination as the response values,and the optimized optimal conditions were: fermentation time 36 h,temperature 35 ℃,inoculum amount 20 %,through the optimized optimal fermentation conditions,the herbal-probiotic composite preparation was prepared.3.Evaluation of the effect of herbal-probiotic compound microecological preparation for swineThe safety and stability tests showed that the compound preparation was non-toxic and could be subjected to subsequent animal experiments.Mice and Anqing six white swine were divided into five groups and each group was fed as required to determine the evaluation of the effect of the compound preparation.The results of stability and irritation test proved that: the p H value of the compound preparation of Chinese herbal medicine-probiotics was less affected by different conditions and the difference was not significant(P>0.05).The feeding test of mice showed that: the weight of liver and spleen in the compound preparation group were significantly higher than other groups(P<0.05),and the meat ratio was also significantly lower than other groups(P<0.05),the content of IL-6 in serum was significantly higher than that in the lactobacillus group,the bacillus group and the control group(P<0.05),and the content of IFN-γ was significantly higher than that in the lactobacillus group,the bacillus group and the control group;the intestinal contents of mice were The number of E.coli in the intestine of the compound preparation group was lower than that of the Lactobacillus group,the Bacillus group and the control group,while the number of Lactobacillus in the intestine was higher than that of the Lactobacillus group,the Bacillus group and the control group.The swine feeding test proved that: the body weight growth rate of the compound preparation group was significantly higher than other groups(P<0.05),and the meat ratio was also lower than other groups(P<0.05);the number of E.coli in the intestine of the compound preparation group was lower than that of the Lactobacillus group,the Bacillus group and the control group,and the number of Lactobacillus in the intestine was higher than that of the Lactobacillus group,the Bacillus group and the control group when the swine’ feces were counted by dilution coating.In summary,this experiment successfully screened out two strains of probiotic bacteria with heat and acid resistance,bile salt resistance and no inhibition of each other,as well as four kinds of traditional Chinese medicine that have no inhibitory effect on probiotic bacteria,and successfully prepared a compound preparation of traditional Chinese medicine and probiotic bacteria after optimizing the fermentation conditions. |
PDF Full Text Request