Experimental reproduction of rotavirus and <i>Salmonella pullorum</i> gastroenteritis in broiler chicks

Abstract

Numerous viruses, including astroviruses, reoviruses, rotaviruses, coronaviruses, and adenoviruses, have been implicated as causative agents of enteric disease. This is because they have been isolated from or identified in the intestines and intestinal contents of affected poultry flocks. Four experiments were conducted to reproduce enteritis in broiler birds using rotavirus and Salmonella pullorum. Fifty-two broiler birds were obtained and randomly divided into 4 groups. Group A chicks were inoculated with 1 X 10 6 pfu/ml of rotavirus, group B chicks were inoculated with 1 X 10 6 cfu/ml of Salmonella pullorum, group C chicks were inoculated with 1 X 10 6 pfu/ml of rotavirus and 1 X 10 6 cfu/ml of Salmonella pullorum, while group D birds were given 1ml of PBS alone. Birds in all groups were observed daily for clinical signs and the intestines were processed for histopathological evaluation. Diarrhea and depression were the major signs in chicks given any one of the inoculum. Histological changes were characterized by swollen villus tips and constricted villus bases, proliferation of enterocytes and necrotic villi. Significant growth retardation was observed in chicks given either rotavirus or Salmonella pullorum, but this effect was more pronounced in chicks given the combination of rotavirus and Salmonella pullorum. The present study reveals that oral inoculation of birds with rotavirus or rotavirus/Salmonella pullorum combination leads to diarrhoea and significant growth depression. It is thus important to continuously screen and prevent against organisms infecting the GIT for optimal performance of birds.