Fatal enteric disease reproduced in guinea pigs by oral administration of pollen beetle ( Astylus atromaculatus )

The ingestion of the pollen beetle Astylus atromaculatus causes gastroenteric disease in ruminants and possibly in other species. No toxic principle has been identified in these insects. Two studies were conducted to evaluate the effects of oral administration of A. atromaculatus in guinea pigs using fresh insects (n = 3) and insects dried for different periods (2, 30, 60, 120, or 240 days) (n = 5). All animals became sick and died spontaneously between 10 and 96 hours after inoculation. Clinical signs included depression; reluctance to move, eat, and drink; kyphosis; and increased frequency of vocalization, with no differences observed between the 2 experiments. Gross and microscopic findings consisted of diffuse ulcerative, fibrinonecrotizing, and hemorrhagic enteritis. No differences were observed in the type or severity of lesions between the 2 experiments or in animals inoculated with beetles dried for different durations. No clinical signs or lesions were observed in guinea pigs from the control group (n = 2). This study adds to the knowledge of A. atromaculatus-associated fatal gastroenteric disease in non-ruminants and highlights the persistent harmful effects of dried pollen beetles.