Feeder insects differ in passage of coccidian oocysts in captive reptiles

Coccidia (Apicomplexa) may have a devastating effect on captive reptiles, particularly chameleons and bearded dragons (Pogona vitticeps). This study investigated the potential of three common feeder insects - the Argentine cockroach (Blaptica dubia), the banana cricket (Gryllus assimilis) and the superworm larva (Zophobas morio) - to act as passive vectors for coccidian oocysts, specifically Isospora amphiboluri and Choleoeimeria pogonae, common enteric parasites of captive bearded dragons. Faecal samples from experimentally infected bearded dragons were fed to the insects to assess the passage of viable oocysts through their digestive tracts. Gryllus assimilis exhibited the highest passage rates for both coccidia, followed by B. dubia; Z. morio showed the lowest rates. However, only G. assimilis passed both I. amphiboluri and C. pogonae at a significantly higher rate than Z. morio. These findings suggest that feeder insects, particularly crickets, can act as mechanical vectors for coccidia, highlighting the importance of strict hygiene protocols in reptile keeping minimizing the risk of parasite transmission.