Heamatological and biochemical status of cultured and wild blue Tilapia, Oreochromis aureus from Alau Lake, Northeast Nigeria.

Blood parameter assessments are sensitive diagnostic tools used to monitor the health status of fish and consequently the aquatic environment where the fish are inhabited. The culturing of Oreochromis aureus is becoming popular in Nigeria and there is a need for baseline parameters for the species. This study therefore examined the haematological and biochemical profiles of cultured and wild Oreochromis aureus from Lake Alau in Northeast Nigeria. Twenty (20) live specimens each of cultured and wild O. aureus (349.50 ± 42.52 g) were used for the study. Blood samples were taken via the caudal peduncle for haematological and serum biochemical analysis using standard techniques. Water samples from Oreochromis aureus culture tank and Lake Alau were collected in triplicate to monitor critical water parameters such as dissolved oxygen, pH, nitrate, nitrite and temperature. Data were analyzed using descriptive statistics, T-test and Pearson's correlation. All statistical significance was tested at 5% significance level. Higher white blood cells count, increased packed cell volume with lower haemoglobin and platelet counts were observed in wild O. aureus. Wild O. aureus also showed elevated albumin levels; however, aspartate aminotransferase and alanine aminotransferase were higher in cultured O. aureus. The results showed marginal variations (p > 0.05) in haematological constituents between the two groups but marked difference (p < 0.05) in biochemical analytes tested. The differences in the habitats of O. aureus caused significant biochemical changes with no significant changes in haematological indices. Further studies on the haematological and plasma biochemical changes in this species of fish under unusual environmental stress will aid understanding of the physiological response of the blue tilapia to environmental stressors. [ABSTRACT FROM AUTHOR]