Haematological Profile and Basic Biochemical Characteristics of Wild-Caught Nile Tilapia (Oreochromis niloticus) from the Vellar Estuary

Abstract

Nile tilapia (Oreochromis niloticus) is an important fish species widely distributed in freshwater and estuarine environments. The present study was conducted to assess the basic haematological and serum biochemical characteristics of apparently healthy wild-caught Nile tilapia from the Vellar Estuary, Parangipettai, Tamil Nadu, India. A total of 30 apparently healthy fish were collected and examined for morphometric characteristics, selected water-quality parameters, haematological indices and serum biochemical parameters. The total length of the fish ranged from 15.3 to 24.5 cm, while body weight ranged from 92 to 203 g. During sampling, the water temperature, pH, dissolved oxygen and salinity were 26°C, 7.2, 4.6 mg L⁻¹ and 21 ppt, respectively. The mean RBC count, WBC count, haemoglobin concentration and PCV were 2.08 ± 0.28 × 10⁶ cells mm⁻³, 50.72 ± 8.81 × 10³ cells mm⁻³, 7.86 ± 0.82 g dL⁻¹ and 31.60 ± 2.48%, respectively. Serum glucose and total protein concentrations showed mean values of 75.97 ± 8.16 mg dL⁻¹ and 4.30 ± 0.39 g dL⁻¹, respectively. The findings provide baseline information on the haematological and biochemical characteristics of apparently healthy wild-caught O. niloticus inhabiting the Vellar Estuary. These baseline observations may be useful for future assessment of seasonal variation, environmental stress and health-related changes in Nile tilapia populations.