Isolation of the respiratory syncytial virus from calves with respiratory diseases

: Described is a respiratory enzootic in calves aged 30 to 90 days. Two cytopathic strains of the bovine respiratory syncytial virus were isolated from diseased calves in a cell culture of lamb thyroid. Clinical observations and the results of virologic and serologic investigations have revealed that mixed infections of the respiratory syncytial virus and the mucosa disease virus take part in the etiology of the respiratory enzootic described.