Haematological Responses Of Oreochromis Niloticus (Trewavas) Exposed To Various Concentrations Of Poisonous Extract From Two Local Plants

Abstract

Haematological studies were carried out on the blood Oreochromis niloticus juveniles exposed to various concentrations of poisonous extracts from two itcheotoxic plants, Parkia biglobosa (clappertoniana) and Tephrosia vogelii in separate bioassays. Haematological parameters invested include Hb, RBC, WBC, Platelet, Lymphocyte and Neutrophil counts, PCV/Haematocrit, MCV, MCHC and MCH values. Various physico-chemical parameters of the test water were also examined. These increased in value with increase in concentration of extract in water except for dissolved oxygen which had an inverse proportion to temperature and pH which reduced slightly with increase in concentration of extract in test water. Haematological analysis of the blood of the fish examined showed that Hb, RBC, PCV, MCH and Platelet count reduced in value with increase in concentration of extract in water of both bioassays, while WBC, Lymphocyte and Neutrophil counts increased with increase in concentration of extract in water of both bioassays. It was concluded that both plant extracts were poisonous and had significant depressive effect on the blood forming system as well as on the immune system of the fish and also affected the physico-chemical nature of the test water, which adversely affected the health of the fish.

Keywords: Haematological, Oreochromis niloticus, poisonous extracts, local plants.

Nigerian Journal of Fisheries Vol. 5 (1) 2008: pp. 23-30