A study of nasal and visceral schistosomosis in cattle slaughtered at an abattoir in Bangalore, South India.

The authors studied the incidence of nasal and visceral schistosomosis in 300 male cattle that were slaughtered in 2001 at the Karnataka Meat and Poultry Marketing Corporation Limited abattoir in Bangalore, South India. The nasal and intestinal scrapings and their contents were screened for eggs and the nasal and visceral cuttings were examined for worms. Eggs of Schistosoma nasale and S. spindale were observed in 197 and 151 samples and worms in 218 and 204 carcasses respectively. A mild infection of S. nasale was observed in 129 animals and a mild infection of S. spindale in 124 animals, a moderate infection of S. nasale was found in 77 animals and a moderate infection of S. spindale in six animals. Twelve animals were heavily infected with S. nasale and 14 cattle were heavily infected with S. spindale. Mixed infections of both species occurred in 163 animals. The level of infection was determined by the eggs per gram method and was found to be in the range of 1 to 310 eggs per gram for S. nasale and 1 to 201 for S. spindale, this was a higher result than the eggs per cubic centimetre method, which indicated lower egg counts. Worms were recovered from 218 nasal and 204 visceral cuttings. It was concluded that the incidence of nasal and visceral schistosomosis in cattle in this region is under-diagnosed and the carrier status of these animals in the subclinical state is potentially high.