Neutralization of the pharmacological effects of Cobra and Krait venoms by chicken egg yolk antibodies.

Five-month-old white leghorn chickens were immunized with 50 microg of Common Cobra (Naja naja) and 30 microg of Krait venoms (Bungarus caeruleus) to generate antivenom antibodies against the venom antigen. Chickens received booster doses of increasing concentrations of venom at 14 days time intervals to raise the antivenom level in egg yolk. The antivenom from immunized chicken egg yolk was extracted by polyethylene glycol (PEG) and ammonium sulphate precipitation method which was further purified by DEAE cellulose ion exchange column chromatography. A high molecular weight protein of 180 kDa was detected by electrophoretic analysis which shows the purity of antivenom generated in chicken. Antibodies generated were specific and sensitive to the venom antigen. Various pharmacological activities of Cobra and Krait venoms were carried out by both in-vivo and in-vitro methods. The neutralization of lethality, hemorrhagic, edema, PLA(2) and procoagulant activity was evaluated in assays involving pre-incubation of venom and antivenom prior to testing. The antivenom was effective in neutralizing the toxic and enzymatic activities of venom. The LD(50) of venom for 18 g of mice was found to be 10 microg for Cobra and 3 microg for Krait venoms. The median effective dose (ED(50)) of anti-Cobra venom was 4.48 mg/5LD(50) and 1.0 ml neutralized 0.127 mg of Cobra venom and the median effective dose (ED(50)) of anti-Krait venom was 3.18 mg/5LD(50) and 1.0 ml neutralized 0.051 mg of Krait venom. The results indicate that antivenom generated in chicken could be used for therapeutic purposes in case of snakebite envenomation.