Hematological Parameters Of Freshwater Fish Species In Morogoro,Tanzania

Abstract

Hematological parameters of four freshwater fish species of the genus Oreochromis (Tilapia) (O. niloticus, O. karomo and O.urolepis) and the genus Clarias (catfish) (C. gariepinus) from natural and artificial habitats in Morogoro Tanzania were investigated using standard procedures. 122 samples (23 catfish, 99 tilapia) were used to study haemoglobin concentration (Hb), hematocrit (%), packed cell volume (PCV)), and erythrocyte and leukocyte counts. Three species; O. karomo, O. urolepsis and C. gariepinus were obtained from Mindu dam (natural habitat). One species, O. niloticus was obtained from Kihonda aquacultural concrete tank culture system (artificial habitat). Catfish had significantly (P<0.05) higher values of all the measured parameters compared to tilapia from either of the two sources. Male catfish had significantly (P<0.05) higher PCV and Hb values compared to females. Except for higher values for white blood cell (WBC) counts in female tilapia (P<0.05) compared to males, there were no other differences between the measured parameters in tilapia with respect to species or sex. Female tilapia reared in a natural habitat had higher PCV and lower WBC compared to those reared in artificial habitat. In contrast, male tilapia reared in artificial habitat had higher WBC, but lower Hb compared to those reared in a natural habitat. This study provides basic haematological data of catfish and tilapia fish reared under tropical conditions. Results indicate that haematological parameters of fresh water fish depend on the species, sex, and the type of habitat, and denote consideration of these factors at the time of utilizing haematological parameters for diagnostic purposes