• Adebambo, A A R.
  Department of Biological Sciences, Tai Solarin University of Education, PMB 2118, Ijagun Ogun State, Nigeria.
  




• Fafioye, O. O.
  Department of Zoology and Environmental Biology, Olabisi Onabanjo University, PMB 2002, Ago Iwoye, Ogun State, Nigeria.
  




• Babarinde, T.A.
  Department of food and Nutrition Security, Hogeschool Van Hall Larenstein University, Larensteinselaan 26-A, 6882 CT Velp, Netherlands.
  




• Oke, A.S.
  Skretting Nigeria Limited. 17, Ibadan – Ife Expressway, Asejire, Oyo State.
  

The study investigated the immune response by white blood cells (WBCs) and its differentials in the African Catfish (Clarias gariepinus) in Ibadan to haemoparasitic infections using microscopy examination for haemoparasites and automated counts for WBCs. Out of the 405 randomly selected matured fish, 60(14.8%) were infected while 345(85.2%) represented the uninfected. The total white blood 3 cell (WBCx10 µl) counts were higher in infected pooled fish (16.99±237.60), similarly in other derivatives of WBC(%) such as heterophils (29.42±1.08), eosinophil (3.33±0.21) and basophil (0.60±0.13), although not significantly different statistically (p>0.05). In contrary, differentials such as lymphocytes (66.71±0.35%) and monocytes (3.04±0.07%) were both higher in uninfected pooled fish than infected ones suggesting a possible immune suppression or modulation due to infection. Exploring the influence of sex and morphometric parameters on haematological indices, the male WBC 3 (x10 µl) counts were higher (17.45±310.94) in uninfected fish than infected ones (16.49±751.30) and ditto both lymphocytes and eosinophil, though the difference were not statistically significant (p> 3 0.05). In females, higher (WBC x10 µl) counts were recorded in uninfected fish (16.54 ± 756.61) than in infected fish (15.91±958.52), similarly monocytes and lymphocytes were both higher in uninfected than haemoparasitic infected female C. gariepinus with no significant difference (p>0.05). Most morphometric values were higher in infected male except mean weight. This is contrary to female where most were higher in uninfected. The varying immune response recorded indicate the need for further investigation on environmental fluctuations in relation to parasitism in Clarias sp.