[Leukocyte enzyme activity in the gamma-ray irradiation of lambs].

: The virologic investigation of clinical and pathological material from calves affected with a respiratory disease at the age of 30 days to 10 months on 16 infected stock-breeding farms led to the isolation of two virus strains (D-117 and Ch-216) on primary cell cultures of fetal calf kidney from the nasal discharge of two 8-month-old calves. By their cytopathic changes, physico-chemical properties and the presence of a group-specific antigen they were said to belong to the adenovirus family. The results of the cross virus-neutralization test pointed to the assumption that they had to be referred to the bovine adenovirus type 1. Discussed is the problem concerning the participation and the importance of individual types of adenoviruses in the acute respiratory enzootics of grown-up calves.