Vet Med - Czech, 2024, 69(2):52-60 | DOI: 10.17221/109/2023-VETMED

Pharmacokinetics of praziquantel and its metabolites in grass carp (Ctenopharyngodon idella) following the oral administration of a single bolusOriginal Paper

R Dobsikova¹, J Blahova², P Marsalek², V Doubkova², E Zuskova³, J Velisek³

¹ Department of Animal Husbandry, Animal Nutrition and Biochemistry, Faculty of Veterinary Hygiene and Ecology, University of Veterinary Sciences Brno, Brno, Czech Republic

² Department of Animal Protection and Welfare and Veterinary Public Health, Faculty of Veterinary Hygiene and Ecology, University of Veterinary Sciences Brno, Brno, Czech Republic

³ South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Vodnany, Czech Republic

The study aimed to evaluate and compare the routes and rates of the depletion of the antiparasitic praziquantel (PZQ), a derivative of pyrazinoisoquinoline, following its oral administration in grass carp (Ctenopharyngodon idella). We focused on the depletion of PZQ and its major metabolites – cis-hydroxy praziquantel (CPZQ) and trans-hydroxy praziquantel (TPZQ), in water, the plasma, hepatopancreas, kidney, muscle, and skin, following a single oral administration of PZQ in a concentration of 50 mg/kg. Fish were sampled before the drug administration and then eight times in the course of the 30-day-long experiment. Our results indicate the rapid absorption and elimination of PZQ and its metabolites in all the analysed matrices. The most PZQ-burdened tissue was the hepatopancreas, the gill and the skin. In all the samples, the concentration of the drug and its metabolites consistently declined over time. The residue of the parent compound was detected for the longest time in all the tissues. During the study, a significant (P < 0.01) correlation was found within the concentration of PZQ, CPZQ, and TPZQ in the water and all the biological matrices. It was also found that the PZQ residue was not detected below the maximum residue levels (i.e., 20 µg/kg) until 16 days after exposure in the muscle and skin.

Keywords: fish; food safety; health; parasites

Received: October 25, 2023; Revised: December 20, 2023; Accepted: January 11, 2024; Prepublished online: February 27, 2024; Published: February 28, 2024  Show citation