INFECTIOUS PNEUMONIA IN SHEEP

In recent years, especially in summer time, infectious pneumonia has been very prevalent among lambs of the Government Sheep Farm at Tomobe (Prefecture Ibaraki), causing great losses every year. The results of our investigation on the disease are summarized as follows:At post-mortem of animals dead from the disease were demonstrated severe anaemia owing to numerous nematodes in the stomach and intestine, pneumonia catarrhalis purulenta lobaris (part of middle lobe, and outer half of anterior and posterior lobes affected) with pleuritis fibroplastica. The histological examination of the affected part of lung revealed hyperaemia, desquamation of alveolar epithelium, exudation of serous fluid, large mononuclear cells and leucocytes in alveoli, leucocytic and lymphocytic infiltration as well as connective tissue production around the bronchioli.From the affected areas of the lung were isolated Bacillus pyogenes, Bacillus ovisepticus, a small Gram-positive bacillus, Micrococcus catarrhalis, a streptococcus, and a staphylccoccus, of which the first three organisms are to be considered most significant for the disease in view of high percentage of their occurrence in pulmonary lesions, their great virulence for the lamb and laboratory animals, and of intimate immunological relations between these organisms and the serum of affected lambs.As the mixed vaccine prepared from these three organisms gave a good result in laboratory animals and a few lambs treated, double treatments with the vaccine were practised this year on the Government Sheep Farm where the administration of vermifuges was enforced at the same time. As the result of the prophylactic measures cases of the disease and losses to the Farm were less than one-tenth those in the previous years.