Typhaea stercorea (Coleoptera: Mycetophagidae), a carrier of Salmonella enterica serovar Infantis in a Danish broiler house

In December 1994, Salmonella enterica serovar Infantis (S. Infantis) was accidentally introduced into a Danish broiler house by stocking an S. Infantis-infected broiler nock of 39,900 day-old chicks. At the time of the study, the infection had persisted through e broiler cycles. Typhaea stercorea (L.), the hairy fungus beetle, was found in large quantities inside and around the broiler house. Various attempts to control the beetle had failed; T, stercorea had been uncontrollable on the farm since Alphitobius diaperinus (Panzer), the lesser mealworm, was eradicated approximate to 10 yr earlier. We investigated the ability of T. stercorea to act as a carrier of S. Infantis in the broiler house between 2 broiler cycles. We examined the empty, cleaned, and disinfected broiler house for S, Infantis 3 d before stocking the 7th broiler nock, and S. Infantis was isolated from the beetles only. Of 20 singly examined T. stercorea, 9 (45%) were S. Infantis positive. A rapid spread of the infection was seen in the 7th broiler nock; 100% of the culled chicks were S. Infantis positive 3 d after stocking. Under experimental conditions chicks were observed eating beetles, and when 5 d-old, specified pathogen free chicks were fed with S. Infantis-positive T. stercorea collected from the broiler house, all 5 chicks became infected in 4 d. We conclude that T, stercorea may act as a potential carrier of S. Infantis between successive broiler cycles.