Pathology of the TrematodeAlloglossidium renalein the Freshwater Grass ShrimpPalaemonetes kadiakensis

Abstract

The trematode Alloglossidium renale was commonly observed in the freshwater shrimp Palaemonetes kadiakensis in Pike County, AL, with a prevalence of 30.2% and 12.7% at two different collection sites. Sectioned antennal glands demonstrated tissue damage near the parasite, including antennal gland tubule cell compression and destruction of host cells. Normal tubules as well as those showing cellular changes were functional and contained parasite ova. Grass shrimp outlive this infection, as evidenced by masses of ova and debris within infected antennal glands, but no viable parasite. The non-lethal nature of the parasite helps to explain the high intensity of infection observed at one of the collection sites. This study furthers our understanding of the effect of this parasite on its host, and extends the reported range of Alloglossidium renale to Alabama.