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Content: Treatment
Penicillin is the drug of choice for the treatment of acutely affected pigs, and it has been used concurrently with antiserum. Penicillin should be given daily for 2-3 days; alternatively, a long-acting form may be used. Improvement is usually seen in 24 hr. Treatment of chronic infection is usually ineffective or not cost effective, and such pigs should be culled. If acute cases develop suddenly in an unvaccinated herd, antiserum, if available, may be administered to in-contact pigs. It may be more cost effective to use a long-acting form of penicillin or tetracyclines before implementing a vaccine program. Prevention is best achieved by regular vaccination using killed bacterins or, in some countries, attenuated vaccines prepared by serial passage or strains of low virulence for pigs. The formalin-killed, aluminum-hydroxide-adsorbed bacterin confers an immunity that, in most instances, protects growing pigs from acute disease until they reach market age. An oral vaccine of low virulence is also used.