Pathogenicity of four strains of staphylococci isolated from chickens with clinical tenosynovitis

Four strains of staphylococci of different phage patterns (two principal and two minor phage types) associated with naturally occurring tenosynovitis were studied for virulence in chickens and tropism for tendon tissue. There were significant differences in virulence between the principal and minor phage types of Staphylococcus aureus. Infection with the principal phage types produced a generalized septicaemic disease and no specific tropism of the bacteria for tendon tissue although there were gross and histopathological changes in tendons and tendon sheaths indistinguishable from those in natural tenosynovitis. However, the pathogenesis of the experimental infections was different from that considered to occur in natural cases and provided further indirect evidence for the secondary nature of the staphylococcal infection in tenosynovitis..