PATHOLOGICAL INVESTIGATION OF PESTE DES PETITS RUMINANTS (PPR) IN GOATS

Abstract

In pathological investigation of peste des petits ruminants (PPR), a total of 11 Black Bengal goats of both sexes about 6-12 months old were included. Six goats out of 11 were suspected to be of natural infection with PPR and 5 goats used for experimentation. Four experimental goats out of 5 were inoculated with PPR virus isolated from natural outbreak and one was used as uninoculated control. The diagnosis of PPR virus infection both in natural outbreak and experimental cases were based on clinical signs, gross pathology, histopathology and ELISA test for confirmation of the PPR virus. Clinical signs included anorexia, depression, fever (106 ± 1°F), oculonasal discharges, diarrhoea with soiled hind quarter, sunken eyes, coughing, respiratory distress and prostration and/or death in natural cases. In experimental infection the goats showed the 5 phases of PPR virus infection cycle which included varying incubation period, prodromal phase, pneumonic phase, diarrhoeic phase and prostration and/or death. Average duration of incubation period was 4 days, prodromal phase 3 days, the pneumonic phase and diarrhoeic phase started at day 5 and 7 of inoculation, respectively and continued till death. Necropsy of both natural and experimental goats revealed stomatitis, congested and/or consolidated pneumonic lungs, generalized enlargement of lymphnodes accompanied with necrosis and congestion of some lymphnodes, atrophied congested spleen and haemorrhagic gastroenteritis. Congestion of the urinary bladder, uterus and vagina in experimental goats and intestinal intussusception in dead goats of natural infection were also found. Histopathological study of both natural and experimental cases revealed congestion and edema of lungs in some cases but in other cases there were network of fibrin infiltrated with neutrophils, formation of syncytia, gaint cell and presence of pink color bacterial colony. There was infiltration of neutrophils and mononuclear cells within the alveoli, bronchioles, alveolar wall and interstitium of lungs. Lymphoid organs showed necrosis and depletion of lymphoid cell; congestion, morionuclear and neutrophilic infiltration in the lamina propria and submucosa of the abomasum, intestine, uterus and urinary bladder; loss of intestinal villi; congestion of cortical blood vessels and glomeruli of kidneys were recorded. Samples of both natural and experimental cases were confirmed as PPR by ELISA test. In this investigation, it was observed that clinical signs, gross and microscopic findings were more severe in experimental PPR infected cases than that of natural cases.