Lechiguana em bovinos: aspectos patogênicos

LADEIRA S; RIET-CORREA F; BONEL-RAPOSO J; CARDOSO PACHECO C; GIMENO EJ; PORTIANSKY EL

CIêNCIA RURAL

UNIV FEDERAL SANTA MARIA

Año: 2010 vol. 40 p. 944 - 949

0103-8478

Two cattle were infected at the left scapula with larvae of the Dermatobia hominis, while one of them was infected with the Mannheimia granulomatis. Biopsies of the lesions were taken at the 7, 14, 21 and 28 days p.i. for their later histopatological, immunohistochemical and electron microscopical studies. In the animal just infected with larvae, dermatitis eosinophilic, infiltration of mononuclear cells and proliferation of connective tissue characterized the histological lesions. The simultaneous inoculation of Dermatobia hominis and Mannheimia granulomatis caused, besides the characteristic lesions of the parasitosis, linfangitis and eosinophilic microabscesses, similar changes to those observed in spontaneous cases of the disease. In the samples taken after 28 days of the bacterial infection it was observed, immunohistochemically as well as through the electronic microscopy the presence of apparently intact bacterial bodies inside macrophages fagosomes, suggesting that the bacteria is inside the macrophages until some unknown factors can trigger the development of the illness.