Application of a real-time PCR assay for the detection of Henneguya ictaluri in commercial channel catfish ponds.

The article presents a research on the myxozoan parasite Henneguya ictaluri that caused the proliferative gill disease (PGD) in channel catfish Ictalarus punctatus. It notes that the extensive gill damage was caused by prolonged exposure of channel catfish to the actinospore stage of the parasite, resulting to reduced production and significant mortality in commercial operations. Findings showed that increases in parasite load correlated with percent mortality in sentinel fish, as did increases in mean actinospore concentrations. It is believed that both applications are more rapid than current protocols for assessing the PGD status of a catfish pond and identified actinospore levels that correlate to both high and low risk of fish loss.