The bacterial agents of ovine and caprine pneumonia and associated gross pathological lesions were studied for a period of ten years (1985-1995). Bacteriological data were obtained from the necropsy report books of the Microbiology and Pathology Dagnostic units of the Department of Vetinary Pathology and Microbiology, Ahmadu Bello University, Zaria, on 283 Pathologic lung samples. The major bacterial agents isolated from affected ovine lungs were E. Coli 24.7%; Pasteurella multocida 17.3%; Arcanobacterium pyogenes 14.9%; Streptococcus pyogenes 6.9%; and Neiseria catarrhalis 5.7% and from caprine lungs were E. Coli 26.6%; Pasteurella multocida 13.8%; Staphylococcus aureus 16.5%; Aracanobacterium pyogenes 11.9%; Streptococcus pyogenes 8.2%; and Proteus vulgaris 5.5%. There were more cases of ovine pneumonia (61.5%) than caprine (38.5%). In both sheep and goat, more cases of pneumonia were recorded during the dry season, with the highest monthly average value for both occurring in January. Annual distribution of ovine Pneumonia was highest in 1990 (24.7%), followed by 1987 (21.8%), while caprine pneumonia was highest in 1990 (22.9%) followed by 1998 (21.1%). The findings of this study suggest a high susceptibility of small ruminants in Zaria to bacterial pneumonia during the early dry season and early rainy season. It is recommended that adequate management measures should be instituted to protect stock during these periods of high vulnerability. Global Journal of Pure and Applied Sciences Volume , No 1 January (2001) pp. 57-60
KEY WORDS: Seasons, small ruminants, bacterial pneumonia.