Probiotics For Haemophilus Parasuis Infection Disease Prevention Research

Haemophilus parasuis（HPS）is a resident bacterium of the upper respiratory tract of pigs,which usually comes on when the body’s immune capacity is low.There are many serotypes of this bacterium,as well as varying degrees of drug resistance.Currently,the inactivated vaccine is widely used in the prevention of HPS,but its application area is limited.Although the multi-valent vaccine has appeared,the limited effect still cannot effectively prevent the occurrence of the disease.In recent years,the probiotic function of probiotics has been gradually developed,which has a significant effect on the prevention of diseases in clinical practice.Therefore,it gives us a revelation whether probiotics can be used to improve the immune capacity of the body in the prevention and treatment of HPS diseases,so as to inhibit the occurrence of HPS diseases.This study is to look for probiotics that can inhibit the growth and reproduction of HPS and improve the immune capacity of the body,so as to provide scientific basis for the clinical prevention and treatment of HPS disease and the rapid development of pig breeding industry,which has important practical significance and application value.Experiment 1:first of all,from the food,feed and environment that may contain probiotics,separation and purification of bacteria liquid after four different treatment ways,reuse bacteriostatic experiment,scraps of paper AGAR diffusion method bacteriostatic experiment and growth inhibition test screening of probiotic strains can effectively inhibit the growth of HPS,and identified.The results showed that:1.MRS,TSB,TSA and other medium were used to isolate multiple strains of probiotics,and 3 strains of probiotics that could effectively inhibit the growth of HPS were selected.2.Through the gram staining,PCR identification and sequencing analysis of the effective strains,the three probiotics were identified as lactobacillus plantarum,streptococcus thermophilus and lactobacillus dei Bulgarian subspecies（also known as lactobacillus bulgaricus）.3.The curve of the relationship between the concentration of bacteria and OD₆₀₀ was calculated according to the data,as the basis for the subsequent challenge test.Experiment 2:70 KM rats（only female）were randomly divided into 7 groups,they were blank group,PBS control group,challenge group,probiotic-1 group,probiotic-2 group,probiotic-3 group and mixed probiotics group.use probiotics to mice stomach,after 21 d to 5type HPS poison,and detection of T lymphocyte subgroup IgA each index and the content of sIgA results show:1.The clinical and histopathological examination showed that in a given amount of HPS poison attack,probiotics can provide a degree of protection to mice,to alleviate the pathological damage of HPS on the organs of KM mice.2.After the application of probiotics CD4+/CD8+ratio and poison attack group no significant difference（P>0.05）,but with the blank group and PBS group is no significant difference（P>0.05）,showed the probiotics to maintain the body’s cellular immune function has certain effect,thus against pathogenic role of the HPS.3.the probiotic group and poison attack than the percentage of peripheral blood mononuclear cells were significantly or extremely significantly reduced（P<0.05 or P<0.01）.At the same time,the percentage of neutrophils in probiotic-1 group and probiotic-3 group was also significantly reduced（P<0.01）.,both are closer to the control group 4.SIgA content in each probiotic group increased.among them,the sIgA level in probiotic-1 group was significantly or extremely significantly higher than that in the challenge group and the control group（P<0.05 or P<0.01）.suggesting probiotics-1 induced mucosal immunity effect is best,can establish mucosal immune barrier for the body to prevent the attack of HPS this study results show that probiotics for HPS infection disease have a certain preventive effect,some of its mechanism is probably by increasing the level of cellular immunity and mucosal immunity...