Prevalence of campylobacter in pigs during fattening; an epidemiological study.

Numerous epidemiological reports implicate foods of animal origin as vehicles of human campylobacteriosis. Pigs are probably an important reservoir of campylobacter and a potential source of human infection. In order to improve our knowledge of the epidemiology of campylobacter in pigs, the prevalence of campylobacter and its contamination of feed were monitored in eight pig farms. Faeces samples of pigs aged 11 and 22 weeks, and samples of rectal, ileal and gastric content at a slaughterhouse were collected for bacteriological examination. On 5 farms, subsequent groups of pigs housed in the same stalls was sampled, too. A selection of the campylobacter isolates was characterized with a genetic typing method (RFLP). More than 85% of the sampled porkers were shown to be intestinal carriers of campylobacter at all stages of fattening. Subsequent groups of pigs housed in the same stalls were all carriers, too. The level of campylobacters in the faeces tended to decrease as the pigs got older. There was no difference in the frequency and level of infection with campylobacter between porkers on different farms. The feeding system (wet feed versus dry pellets) did not seem to influence the prevalence of campylobacter although wet feed gave lower counts of Enterobacteriaceae in the faeces. RFLP-typing showed a high diversity of campylobacter strains at each sampling on the farm. Similarities were seen between strains isolated during two subsequent samplings of the same group of pigs, but not between strains isolated on the same farm from subsequent groups of pigs housed in the same stall. This suggests that the piglets were already infected at a young age on the breeding farm.

Some aspects of the gastrointestinal microflora of veal calves fed different rations: a pilot study.

The gastrointestinal microflora of veal calves reared on different diets was studied because the nature of this microflora affects the quality of veal as a result of contamination of carcass surfaces with intestinal contents during slaughter. Diet A consisted of a milk substitute, diet B of milk substitute + straw pellets and diet C of milk substitute + straw pellets + concentrates. In the rumen fluid of calves reared on diet A significantly higher counts of Gram-negative bacteria but lower counts of thermotrophic enterobacteriaceae were found than in calves reared on diets B or C. As for the faecal flora, diets B and C seem to result in significantly lower counts of Gram-negative bacteria and thermotrophic enterobacteriaceae. In 46% of the faecal specimens and 62% of the specimens of rumen fluid from calves fed on milk substitute only, Pseudomonas aeruginosa was isolated in mean counts of 4.1 log cfu/g and 5.2 log cfu/g respectively. P. aeruginosa could not be isolated from any specimen from calves receiving straw pellets. These results indicate that the inclusion of straw pellets in the diet of veal calves may increase the bacteriological safety and keeping quality of veal.