Epidemiological Investigation And Control Of Edema Disease Of Piglets In Haian County

Since the first report of edema disease(ED) of piglets (Shanks, 1938), this disease now is epidemic in all porcine breeding countries around the world. This disease most occurred in well development piglets one to two weeks post weaning. Usually is sudden outbreak, and have a high incidence that is about ten to forty percent. According to the primary statistic, there are about 20,000 piglets were affected with the disease, and about 5,000 were dead from the disease in HaiAn county every year. This caused a direct loss of about 2,000,000 yuans per year. So to decrease the economic loss and effectively control the disease, it is necessary to investigate the epidemiology of edema disease of piglets . And this work would benefit the control of piglets edema disease.In this paper, we investigated the incidence of the disease and the mortality of piglets edema in several towns of HaiAn in 2003. The investigating results demonstrated that piglets edema disease is sporadic in HaiAn district. The incidence of the disease in Haian county is about 0.29-1.36 percent; the mortality is about 0.08-0.35 percent; mortality in affected herds is about 16.0-35 percent. This disease most occur in post-wean piglets, occasional in breeding pig. And most occur in April,k May, September and October every year. Twenty-two strains of Escherichia coli have been isolated from samples of affected cases. Among these E. coli strains via 0 seragroup identification, five were 0,39, two were O45, and another five were O55, O93, O9, 0101 O119 respectively. By multi-PCR and monoclonal antibodies identification of toxins gene and fimbriae antigen, six strains gene type were SLT- II e, five out of six if belong seragroup O139, one out of six is belong to seragroup O55; other six strains are STb gene type. Among the twelve strains there are four F18 fimbriae expression strains (two O139, one O45 and one O119); fimbriae F5+F41 one strain, fimbriae F41+F18 one strain, two strains of F5+F41+F18 (O139). By antibiotic susceptibility test, most strains are highly sensitive to enrofoxacin, gentamycin, and spectinomycine. We set atherapy scheme where epidemic piglets edema occurred in last two years. In this scheme 0.3-0.5% mixed acidifing reagent and traditional medicine erling powder for regulating micro flora in digestive tract were added into the daily feeds respectively for twenty days. The results demonstrated that the incidence of disease significantly decreased from 25.3% and 22.7% to 1.8% and 0.8%. At the same time we randomly investigated fifty edema epidemic herds to statistic the effectiveness of using sera against edema disease. And the results showed that the effectiveness of drug therapy is higher than that using of sera against edema disease. 378 piglets were chosen as preventing and treatmenting experiments by using compositive method which including followings: muscle injection of medicine called: "Compound Sorbitol injection"and "Sodium Selenite injection", oral administration of Magnesium sulfate to expell toxin. 339 cases were cured, the effectiveness is about 89.7%.The results of epidenilosical investigation and preventive and therapeutical experiments demonstrated that compositive preventive and therapeutical method could effectively control the disease of piglets edema. These methods including adding acidifing reagent or traditional Chinese medicine to the diet, reasonble feeding management, decrease stress, properly configuration of daily feed. For the clinical cases it could increase the effectiveness by finding and treatmenting as early as possible, combined with antibiotic injection and expell toxins and diuresis.