Isolation And Identification Of Clostridium Perfringens And Screening Of Vaccine Strain

Clostridium perfringens,also known as Clostridium perfringens,are present in the intestinal tracts of many healthy animals.When feeding and environmental conditions change,Clostridium perfringens can cause Clostridium perfringens in livestock and poultry.,Will lead to rapid death of livestock and poultry,the course is very short,often in the absence of effective treatment before death.In recent years,Clostridium perfringens has caused the aquaculture industry suffered huge economic losses.Necrotic enteritis(Necrotic enteritis)is a type A or C-type Clostridium perfringens caused by chicken intestinal necrosis,bleeding a common disease,prevalent in the country,can occur throughout the year,Especially in the winter and spring season incidence is higher.The disease chickens disease suddenly,was acute,death fast,high mortality.Dead chickens are full of muscle fat,full of healthy chickens.Most of the chicken chicks,eyelids bruising,a few pale.Some sick chicken with crooked neck,gait stiffness and other neurological symptoms.The Chinese chicken industry caused many potential threats.The traditional method of preventing Clostridium perfringens infection leads to chicken necrotizing enteritis by adding antibiotics to animal words and drinking water.However,in recent years,the problem of veterinary drug residues has been paid more and more attention,the use of antibiotics in the poultry industry is becoming more and more stringent,leading to the rising trend of chicken necrotizing enterocolitis,the domestic and international poultry industry To the major economic losses,so the diagnosis and treatment of chicken necrotizing enteritis become particularly important.And vaccination is the best way to reduce the incidence of the disease.In this study,we collected samples of liver and intestine contents from large-scale chicken farms in Shandong province.The isolates were isolated from Clostridium oryzae and cultured in anaerobic culture.The isolation,culture,biochemical identification,Molecular biology identification,were isolated from the five chicken Chicken Clostridium.PCR was used to detect the toxin gene of isolates.It was confirmed that the isolates were Clostridium perfringens type A.The pathogenicity of Clostridium perfringens type A was compared with that of TA-02 and LX-04,and the results were further studied.LX-04 strain showed that the liver cells were granulated degeneration,steatosis,the boundary was not obvious,and see a small necrosis,intestinal mucosal epithelial cells necrotic loss,the number of intestinal glands decreased,mucosal lamina propria,Inflammatory cell infiltration and other typical lesions.In order to reduce the production cost and make the prepared vaccine safer and effective,this study screened the culture conditions of the vaccine strain in vitro.The results showed that the culture was carried out at 42? for 5 hours at 10%inoculation amount.Less metabolic substances,the vaccine safer.The 7-day-old SPF chickens were immunized with 1:2 ratio of 1:2 emulsified virus.The protection rate of LX-04 strain was 80%after three weeks of immunization,and the effect was good.Screening out the vaccine strains for Clostridium perfringens vaccine,and provide the basis for the development and prevention of Chicken Clostridium toxin vaccine and the diagnosis and prevention of chicken necrotizing enteritis.