Development of preventive method for enterotoxigenic colibacillosis using egg yolk antibodies II. Therapeutic effect of egg yolk antibodies against colibacillosis of piglets

난황항체를 이용한 돼지 대장균설사증 방제기법 개발 II. 난황항체의 돼지 대장균증에 대한 치료효과

The present study describes the effectiveness of egg yolk antibodies (IgY) against enteric colibacillosis and edema disease in piglets. The antibodies were gained from the egg yolk of hens immunized with k88, k99, 987p fimbrial adhesin and heat-labile toxin antigens of enterotoxigenic Escherichia coli (ETEC). Orally-administered egg yolk antibodies solution protected against experimental challenge with ETEC $K88^+$ and $k99^+$ strains in neonatal piglets and mice. In field trial, a total of 598 diarrheal piglets were orally treated with 3ml of antibody once a day to determine for the therapeutic effect. Of them, 582 (97.3%) piglets were recovered from diarrhea in 3 days. We also experimentally treated with the egg yolk antibodies twice a day for 5 consecutive days for 94 weaning piglets with edema disease for the determination of therapeutic effects. Seventy four piglets (78.7%) were recovered from clinical edema signs. Theses findings indicate that egg yolk antibodies against k88, k99, 987p and LT of ETEC are useful source of passive immunity for enteric colibacillosis and edema disease of piglets.