Variation in Growth and Condition Factors of Three Commercial Fish Species in Habitats Associated with Rice Paddy Fields in An Giang Province, Vietnam

The assessment of the length-weight relationship and condition factors was carried out for three commercial fish species, Esomus metallicus Ahl, 1923, Anabas testudineus (Bloch, 1792) and Trichopodus trichopterus (Pallas, 1770). The survey was carried out in habitats influenced by human activities associated with rice paddy fields in three areas situated in An Giang Province. Vietnam: Luong Phi, islets in An Thanh Trung and Hau riverside in Vinh Thanh Trung. The relationship between length and weight showed the slope values (b) of the three species between 2.75 and 3.29; the growth patterns in them (negative allometry, positive allometty and isometry) varied depending on site and time of sampling. The b values in the three species were close to the critical isometric value (3), which could indicate that these species were highly fit for these conditions. No significant difference in the condition factors were observed in Anabas testudineus and Trichopodus trichopterus sampled from areas inside dike systems and outside them as well as from periods of the three consecutive rice crops produced annually in this region. Variations in this effect were more evident for Esomus metallicus. The condition factors of these species were close to the well-being value, showing the prospective for culturing them in rice paddy fields. The three species were impacted by the dike-site x crop interaction, showing that they are well adapted to the habitats and the seasonal conditions.