Hormonal and Hematological Responses of Cyprinus Carpio (LINN) to Nitrite Toxicity

Study on hormonal and haematological responses of Cyprinus carpio to nitrite toxicity was carried out to know the magnitude of the effects of this stressor on fish physiology. Haematological responses of Cyprinus carpio to sub-lethal level of nitrite (0.1g L⁻¹) at different exposure h (0, 6, 24, 48, 72 and 96h) were carried out. Blood sample were collected at each exposure h and evaluated for primary and secondary stress indicators. Data obtained were subjected to simple descriptive analysis, analysis of variance and Pearson Product Moment correlation analysis. When exposed to nitrite, there was progressive increase in plasma control level of Cyprinus carpio from ohour to 48hour. This later decreased at 72h, it increased in 96h. PVC and Hb were elevated after 6h of exposure and decreased significantly (p<0.05) at 48h, 72 and 96h of exposure in fish exposed to sub-lethal level of nitrite. RBC level decreased significantly at 6h, this was followed by significant increase at 24h. The RBC value later decreased gradually at 96h. This study shows that hormonal and haematological balances of Cyprinus carpio was affected on short term exposure to nitrite toxicity.