Evaluation of Praziquantel Efficacy against Zeuxapta seriolae Infections in Greater Amberjack, Seriola dumerili

The aim of this study was to evaluate the efficacy of dietary praziquantel (PZQ), a promising fish anthelminthic, against Zeuxapta seriolae, a lethal ectoparasite of greater amberjack (Seriola dumerili Risso) farmed in the Mediterranean and elsewhere. The trial was carried out in small cages (3 m(3)) in situ, harbouring fish (125 +/- 14 g) naturally infected with Z. seriolae, at 25 +/- 1 degrees C water temperature. Praziquantel-medicated diet (150 mg PZQ/kg fish) was delivered for three days against a control group. Measurement of both adults and oncomiracidia of Z. seriolae in sampled gill arches revealed significant differences between the tested groups (PZQ: 19.3 +/- 9.8 vs. Control: 3.8 +/- 6.3). Considering an estimated efficacy of 80.4% in the medicated fish, the present study indicates that oral PZQ treatments can confront Z. seriolae infections considerably in farmed greater amberjack and, perhaps, replace the commonly used hydrogen peroxidase baths.

Automated summary

The study demonstrated that oral PZQ treatments can significantly combat lethal ectoparasite infections in farmed greater amberjack, potentially replacing commonly used hydrogen peroxide baths.