Longevity and viability of Taenia solium eggs in the digestive system of the beetle Ammophorus rubripes / Duração e viabilidade de ovos de Taenia solium no sistema digestivo do besouro Ammophorus rubripes

ABSTRACT

The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle's digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas.

RESUMO

Este estudo avaliou a duração e viabilidade de ovos de Taenia solium no sistema digestivo do besouro Ammophorus rubripes como portador dos ovos de T. solium. Cem besouros foram distribuídos em cinco caixas de polietileno, contendo um grama de fezes bovina misturada à proglotes grávidas de T. solium trituradas. Após 24 horas, cada grupo de besouros foi transferido para uma caixa limpa e, a cada três dias, cinco besouros foram dissecados para determinar a contagem e viabilidade dos ovos nos intestinos de cada besouro. Ovos de T. solium foram detectados no sistema digestivo até 39 dias (13° dia da amostragem de 20), observando-se uma redução gradativa do número e viabilidade dos ovos, até 36 dias após a infecção. A viabilidade dos ovos foi de 40% após 24 horas da infecção, com uma média de 11 ovos por cada besouro. Besouros coprófagos têm potencial para contribuírem na dispersão dos ovos de T. solium em áreas endêmicas.