Clinicopathological observations in experimental peste des petit ruminants virus and Mannheimia haemolytica A:2 co-infection in goats.

The experiment describes for the first time the clinicopathological features of the co-infection of Peste des petit Ruminants (PPR) virus and Mannheimia haemolytica,in goats. Twenty clinically healthy goats, six months of age were used. 15 goats were infected by intratracheal inoculation of 1ml of pure cultured 106.5 TCID50 PPR virus grown in Baby hamster kidney cell lines, and a week later,1 ml of pure culture (109 CFU) of Mannheimia haemolytica (MH)A2 to study its clinico-pathological features and five goats served as controls. The clinical signs were observed and two goats were euthanized at predetermined intervals for gross examinations, bacteriological, virological and histopathological investigations on tissues collected using standard techniques. The clinical signs were severe and the order of manifestation was anorexia, pyrexia, dyspnea, oculo-nasal discharge, recumbency and death. The lesions observed were severe fibrinous bronchointerstitial pneumonia and pleurisy with thickened alveolar septa, edema and neutrophilic infiltrations of the interstitium with giant cells. There was also marked erosive stomatitis and acute enteritis. The average percentage lung consolidation for the infection was 7.01% and the right lung was more affected (p<0.05) while the overall mortality was 33.3%. MHA:2 and PPR virus were re-isolated from the lungs. The clinicopathological features observed showed that goats were susceptible to co- infection of PPR and Mannheimiosis which was severe and fatal. The data should help veterinarians and other medical experts to recognize cases of bacterial complicated viral infection and be informed of the approach to the treatment of such conditions.