GASEOUS LYMPHADENITIS IN GOATS - THE DOSE OF INFECTION AND THE SEROLOGICAL RESPONSE

Goats were infected intradermally with caseous pus containing between 1 x 10(5) and 5 x 10(1) colony forming units (CFU) of Corynebacterium pseudotuberculosis. Animals infected with doses of equal and above 1 x 10(2) CFU of the organism developed caseous lesions in regional drain ing lymphnodes while those infected with lesser doses developed none. On serological examination, 3/6 animals infected with equal to or less than 1 x 10(3) CFU and 2/4 infected with equal to or less than 1 x 10 (2) CFU had no positive bacterial agglutination and antitoxin antibody titres respectively. These results indicated that caseous lymphadenit is (CLA) is a highly contagious disease since a relatively low dose (1 x 10(2) CFU) of C. pseudotuberculosis injected intradermally could in duce CLA lesions in draining lymphnodes. The serological response in t erms and rate and extent appeared to depend on the dose of infection.