RESUMO
In 1980, 16 abortions or stillbirths occurred and 26 deformed calves were born in a beef herd of 115 Friesian cross Hereford cows mated to Charolais bulls. The deformities were principally arthrogryposes with contractures, particularly of the forelimbs, and various skull abnormalities. Following investigation it was considered highly unlikely that hereditary causes, infectious agents or a nutritional deficiency were responsible. The most likely cause was exposure to an unidentified teratogen early in pregnancy.
Assuntos
Aborto Animal/etiologia , Artrogripose/veterinária , Doenças dos Bovinos/etiologia , Animais , Artrogripose/etiologia , Bovinos , Doenças dos Bovinos/congênito , Doenças dos Bovinos/patologia , Feminino , Membro Anterior/anormalidades , Membro Posterior/anormalidades , Gravidez , Crânio/anormalidadesRESUMO
Factors influencing the incidence of hypocupraemia and responses to copper therapy were investigated in three beef suckler herds calving in spring and early summer. On farm A hypocupraemia was most severe (plasma copper less than 0.4 mg per litre) in March for the cows and in October/November for their calves. On farm B plasma copper levels were 30 per cent lower in five to eight-year-old cows than in two-year-old cows in late November. Administration of copper (100 mg) in late pregnancy significantly increased plasma copper in the suckled calves on farm A but not in their dams after parturition. Growth of the calves was not increased. The alleviation of severe hypocupraemia on a third farm (C) by injecting the calf with copper did not improve growth rate. It is concluded that in some areas a severe seasonal hypocupraemia may be tolerated without loss of productivity.
Assuntos
Doenças dos Bovinos/economia , Bovinos/crescimento & desenvolvimento , Cobre/deficiência , Ração Animal/análise , Animais , Doenças dos Bovinos/sangue , Cobre/administração & dosagem , Cobre/sangue , Feminino , Masculino , Gravidez , Estações do Ano , Solo/análiseRESUMO
A single dose of inactivated louping-ill oil-adjuvant vaccine elicited a sero-logically detectable immune response in sheep lasting for at least 1 year. These sheep when exposed to a natural focus of louping-ill virus were completely protected from clinical disease and 1 year after vaccination were able to pass on a substantial maternal immunity to their lambs.Twenty-nine per cent of unvaccinated sheep, exposed at the same time, died from clinical louping-ill; half of the survivors showed positive sero-conversion and became immune, while the other half remained susceptible. The incidence of fatal encephalomyelitis in sheep which were known to have circulated virus exceeded 50% in 2 out of 3 trials conducted simultaneously in different locations in Scotland in 1969.