Fish Health Assessment in Relation to Sex and Season: Haematological Variations and Serum Biochemical Constituents of Labeo rohita (Hamilton, 1822) from Kotri Barrage near Jamshoro, Sindh, Pakistan

F ish imitate to situation of water quality and pollution since they existed at the lowest level of food chain of aquatic bodies. They can obtain and retain chemicals like heavy metals and pesticides through submissive phenomena so pollutant in their environment can be identified. Fish consume greater amount of algae, phytoplankton and different aquatic plant infected with pesticide, which consequently Abstract | This study was focused on fish health assessment in relation to sex and season via haematological variations and serum biochemical constituents of Labeo rohita from Kotri Barrage near Jamshoro, Sindh, Pakistan. Fish samples (100 specimens for each sex) were collected during two seasons i.e., summer: March to May, 2017 and winter: November, 2017 to January, 2018. Haematological characteristics of the fish specimens were considered season and sex wise separately. Results showed that erythrocytes (2.09 10 6 to 2.26 10 6 ), leucocytes (164.90 10 3 to145.55 10 3 ) and haemoglobin (10.34 g/100 ml to 7.06 g/100 ml) concentration were significantly higher in male fish during summer and winter than that of female. In female fish, erythrocyte sedimentation rate (ESR) in summer and winter season was found higher (7.3 mm/h to 2.56 mm/h). Thrombocytes, neutrophils, lymphocytes, eosinophil and monocytes did not show any significant difference in their counts of male and female fish during summer and winter season. Important serum constituents like protein, cholesterol and glucose were also assessed and it was reported that serum glucose was found more in male than female fish, while in male protein and cholesterol were high in female in summer. In winter season, female fish showed low level of cholesterol, though protein and glucose remained high. Based on the serum biochemical constituent data, it was concluded that male L. rohita were healthier than the female fish in terms of blood parameters.