HAEMATOLOGICAL AND SEROLOGICAL G' ARACTERISTICS OF HETEROTIS NILOTICUS, (CUVIER AND VALENCIENNES 1829): OSTEOGLOSSIDAE

Abstract

Heterotis niltiocus, is a freshwater fish, endermic to Africa. It has become popular in fish farming in Nigeria, largely due to its ability to breed in captivity, fast growth rate and large attainable size. Studies on the biology of Heterotis niltiocus has been previously focused on the food and feeding habits, as well as age and growth. No information exists on its haematological and serological profile. It Haematoloqical characteristics of 25 adults Heterotis niloticus, specimen (standard length, 30.4cm- 39.5cm) (weight, 340g- 610g) collected from, Osun State Ministry of Agriculture and Natural Resources Fish Farm, Osogbo, Osun State, were established. The blood parameters determined were, red blood cells, white blood cells, haemoglobin, haemotocrit, mean cell haemoglobin concentration, mean cell volume, mean cell haemoglobin, protein,glucose, albumin, sodium, chloride, potassium, magnesium and phosphorus. The red blood cells and white blood cells counts did not positively correlate with physical parameters of length and weight. There were siginificant and positive correlation between the blood cells, haemoglobin and pack cell volume, at P < 0.01 and P < 0.001). The serological (blood grcup, genotype and agglutination test) result were (92% O+ve and 8% O-ve), (56% AA and 44% AS) and 100%-ve respectively, and the result obtained were found to be similar to the pattern in humans. Factors which affected the haematology of the fish were discussed, and these include, stress due to capturing, transportation and sampling, age, sex and vessels in which the blood is taken. The knowledge of haematological and serological characteristics of Heterotis niloticus is important in (1) determining health status of fish. (2) comparative haematological parasitological investigations. studies, for disease, toxicological and (3) selecting brooders for breeding purposes. (4) Seprating the sexes of the fish.