Haematological responses of African catfish <i>Clarias gariepinus</i> (Burchell, 1822) broodstock fed varying dietary levels of groundnut oil

Abstract

A 24-week feeding trial was carried out to investigate the effect of replacement of dietary Fish Oil (FO) with Groundnut Oil (GO) on the haematological parameters of Clarias gariepinus broodstocks. A control diet (G0) without GO and four diets G25, G50, G75 and G100 with GO replacing FO at 25, 50, 75 and 100% levels respectively were formulated. Diets were fed to triplicate groups of C. gariepinus broodstock (Mean weight) for 168 days at 4% body weight in two installments daily. Fish blood samples were collected, for determination of White Blood Cell (WBC), Haemoglobin (Hb), Haematocrit (HCT), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC), Mean Corpuscular Volume (MCV) and Erythrocyte Sedimentation Rate (ESR) using standard methods. Data collected were subjected to ANOVA for means comparison at α0.05. Results indicated that WBC was significantly lower (P< 0.05) in G0 fish (4.46 x 10³/μl) than the other treatments. The highest WBC value of 8.76 x 10³/μl was recorded in G100 fish. There was statistical similarity in RBC and Hb values among all groups, however, G50 (2.82 x 10⁶/μl and 5.78 gdl-1 respectively) values were marginally higher than G0 (2.39 x 10⁶/μl and 5.75 gdl^-1respectively) values. HCT and MCV values (15.98 % and 73.02 fl respectively) were significantly higher (P < 0.05) in G0 group and lowest in G100 group (10.03% and 54.24 fl respectively). ESR values showed statistical similarity (P > 0.05) among all groups. The decreasing trend in values of some parameters above 50% inclusion level is indicative of a compromise in the health status of the fish. Therefore replacement beyond this level is not recommended