Salmonella infection in calves and other animals

Abstract

In a 2!-year survey of salmonella infection in animals being slaughtered at meat works, approximately 5% of 7,497 samples, from 2,755 animals, and the pasture and water supply of five farms, were found to contain salmonellae.The predominant type was S. typhimuriul1l, although a few isolations of S. bovis morbificans, S. senftenberg, S. newington, S. derby, and S. anatU1n were made. About 15% of the cows and sheep, 13% of the calves, and 4% of the beef cattle were found to have salmonellae in one lOr more of the samples examined.The principal source of this infection appeared to be on the farm. N.Z. ]. agric.

Salmonella infection in calves and other animals

“…The proportion of salmonella-infected calves (7.3%) was lower than in the previous study (Nottingham and Urselmann 1961), possibly as a result of improvements in hygiene in the meatworks and on the farm aimed at controlling the spread of this disease. The 1971 results showed little changes from the earlier part of this survey, so the improvement since 1960 appears to have been sustained.…”

“…Usually not more than five animals were sampled on anyone day. The samples were collected and prepared for enrichment as in the earlier survey (Nottingham and Urselmann 1961). Nasal swabs of calves were taken as the carcass joined the legging rail.…”

“…Salmonella infection may result in outbreaks of disease, but very often the animals show no obvious symptoms and appear fit for slaughter. In a previous survey of salmonella infection in animals being slaughtered at meatworks, about 15% of the cows and sheep, 13% of the calves, and 4% of the beef cattle sampled were found to have salmonellae present in one or more of the samples examined (Nottingham and Urselmann 1961). This survey has been extended to include pigs and calves slaughtered during a 4-year period, 1962 to 1965, as well as during July to October 1971.…”

Salmonella infection in calves and other animals

“…little difficulty was experienced in identifying salmonella colonies on this medium. Plating on SS agar after tetrathionate enrichment was not as successful as in the previous study (Nottingham and Urselmann 1961). and it was more difficult to identify salmonella on this medium than on either of the other two plating media used.…”

“…The samples were collected and prepared for enrichment as previously described (Nottingham and Urselmann 1961). As before.…”