Adakole Sylvanus Adah - Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Ilorin, Ilorin, Nigeria.
Deborah Arimie Adah - Department of Veterinary Medicine, Faculty of Veterinary Medicine,University of Ilorin, Ilorin, Nigeria.
Charles Obiora Nwonuma - Department of Biochemistry, College of Pure and Applied Sciences, Landmark University Omuaran, Nigeria.
Taiwo Oyekunle - Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Ilorin, Ilorin, Nigeria.
Boluwaji Olaosebikan - Department of Veterinary Medicine, Faculty of Veterinary Medicine,University of Ilorin, Ilorin, Nigeria.

Background: The transportation of fish is a common practice in aquaculture. However, the transportation of fish results in significant stress that can cause mortality and disease outbreaks due to compromised immune status. To ameliorate the effect of this stress, it is advocated that a suitable antioxidant be supplemented to fish before subjecting to transportation. Objectives: The present experiment was performed to evaluate the effect of melatonin on haematological parameters and water quality indices of Clarias gariepinus post-transportation.Methods: Forty adult C. gariepinus fishes, weighing an average of ۴۵۰.۴۶ g and measuring an average of ۳۸.۲۳ cm and ۴.۴۶ cm were used for the experiment. They were divided into two groups. Group I (MMF) was supplemented with melatonin in their feed every day for one month while group II (OMF) was not administered melatonin. The subjects were fed a commercial pelleted diet once a day throughout the experiment. They were maintained in a tank made of plastic, and water was originally provided through a flow-through system. Haematological and water quality parameters were determined before and after transportation.Results: After the transportation process, erythrocyte count and packed cell volume of the group I was significantly higher (P<۰.۰۵). In comparison to group II, the total leucocyte count, neutrophil count, and neutrophil/lymphocyte ratio of group I were all significantly lower (P<۰.۰۵). After transit, group II had considerably higher quantities of nitrite, nitrate, and ammonia (P<۰.۰۵) than group I. Following transportation, group II had significantly higher nitrite, nitrate, and ammonia (P<۰.۰۵) than group I. However, in group I, dissolved oxygen concentration was greater (P<۰.۰۵) than that of group II.Conclusion: Accordingly, it was concluded that melatonin affected various haematological and water quality variables in C. gariepinus and will ameliorate the stress of transportation.

catfish, haematology, melatonin, Transportation, Water properties