Darkling beetles source of pathogens in broilers

27-11-2008 | Home | News

A study suggests that darkling beetles and their larvae can transmit Salmonella and Campylobacter pathogens to broiler chickens in successive rearing cycles in the broiler house.

Broiler flocks often become infected with Campylobacter and Salmonella, two main sources of human foodborne disease. The exact routes of contamination, however, are reportedly still not fully understood. This study conducted by researchers from Wageningen University, Wageningen, and Research Centre, Lelystad, the Netherlands, looked at the role that darkling beetles and their larvae may play in transfering pathogens between consecutive cycles.

The darkling beetle (Alphitobius diaperinus) and its larvae are known to inhabit broiler houses and are believed to survive between rearing cycles by eating their way into insulation materials and hiding under floors.

In the study researchers artificially contaminated several groups of beetles and their larvae with a mixture of Salmonella enterica Serovar Paratyphi B Variant Java and three Campylobacter jejuni strains. These were then fed to housed broiler chicks either the day of inoculation or one week following to mimic an empty week between rearing cycles.

All the broiler chicks that were fed insects contaminated on the same day showed Campylobacter and Salmonella colonization levels of 50-100%. Insects that were fed a week after infection resulted in transfer of both pathogens as well, but at lower levels. Naturally infected insects collected at a commercial broiler farm and fed to chicks also resulted in colonisation, but at lower levels.

The researchers concluded that the fact that Salmonella and Campylobacter can be transmitted via beetles and their larvae to flocks in successive rearing cycles indicates that there should be intensive control programmes for exclusion of these insects from broiler homes.

Source: Science Daily