J Vet Sci.  2024 Jul;25(4):e58. 10.4142/jvs.24118.

Pharmacokinetics of oxytetracycline in hybrid catfish (Clarias macrocephalus x C. gariepinus) after intravascular and oral administrations

• Poapolathep A
• Sriphairoj K
• Hatachote S
• Wongpanit K
• Saensawath D
• Klangkaew N
• Phaochoosak N
• Giorgi M
• Poapolathep S

• KMID: 2558446
• DOI: http://doi.org/10.4142/jvs.24118

Abstract

Importance
Over the past decade, catfish farming has increased in Southeast Asia. However, there has been no existing for pharmacokinetic data in the hybrid catfish (Clarias macrocephalus x C. gariepinus).
Objective
This study was designed to evaluate the pharmacokinetic characteristics of oxytetracycline (OTC) in the hybrid catfish, following single intravascular (IV) or oral (PO) administration at a single dosage of 50 mg/kg body weight (BW).
Methods
In total, 140 catfish (each about 100–120 g BW) were divided into two groups (n = 70). Blood samples (0.6–0.8 mL) were collected from ventral caudal vein at pre-assigned times up to 144 h (sparse samples design). OTC plasma concentrations were analyzed using high-performance liquid chromatography-photodiode array detector.
Results
The pharmacokinetic parameter of OTC was evaluated using a non-compartment model. OTC plasma concentrations were detectable for up to 144 and 120 h after IV and PO, respectively. The elimination half-life value of OTC was long with slow clearance after IV administration in hybrid catfish. The average maximum concentration value of OTC was 2.72 µg/mL with a time at the maximum concentration of 8 h. The absolute PO bioavailability was low (2.47%).
Conclusions and Relevance
These results showed that PO administration of OTC at a dosage of 50 mg/kg BW was unlikely to be effective for clinical use in catfish. The pharmacodynamic properties and clinical efficacy of OTC after multiple medicated feed are warranted.

Keyword

Oxytetracycline; pharmacokinetics; catfish; animal feed; oxytetracycline