Campylobacter jejuniin broilers: the role of vertical transmission

Abstract

SUMMARYThe role of broiler eggs in the transmission ofCampylobacter jejunito broiler grow-out flocks was investigated. Six breeder flocks supplying broiler eggs to hatcheries were examined for cloacal carriage ofC. jejuni. Of 240 birds tested, 178 (74%) wereC. jejuni-positive. Eggs from these birds examined forC. jejunipenetration of the egg shell indicated that 185 of 187 were campylobacter-free. Eggs from breeder flocks of unknownC. jejunistatus were also examined forC. jejunishell penetration.C. jejuniwas not isolated from 142 eggs examined. A further 193 hatchery eggs incubated and hatched in the laboratory were campylobacter-free. Six farms containing the progeny ofC. jejuni-positive breeder flocks were monitored. Eight hundred and forty birds from 14 flocks m these grow-out farms were campylobacter-free during their 6-week grow-out period. Experimental egg-penetration studies indicated thatC. jejunitransmission via the egg is not easily effected. Of 257 eggs surface-challenged withC. jejuni, 162 hatched; all were campylobacter-free. Of 167 eggs injected withC. jejuni, 12 hatched; 2 of these were colonized withC. jejuni. Our data do not support a role for vertical transmission ofC. jejuniin commercial broiler production.