ABSTRACT
A morphometric study to assess the length-weight relationships, condition factor and body length/intestinal length relationship of two (2) freshwater fishes namely Tilapia mariae and Synodontis nigrita, belonging to the families Cichlidae and Mochokidae respectively was conducted in Ikpoba River, Benin City, Edo state, Nigeria over a period of 6 months, spanning from October, 2023 - March, 2024. Morphometric measurements such as Total Length (TL), Head Length (HL), Standard Length (SL), Intestinal Length (IL), Body Depth (BD) and Weight (W) were taken and recorded for each specimen in the laboratory. The range of the Total Length (TL), Head Length (HL), Standard Length (SL), Intestinal Length (IL), Body Depth (BD) and Weight (W) of T. mariae was from 14.8 - 23.2cm, 3.5- 6.3cm, 11 - 19.5cm, 9.4 - 22.6cm, 4.2 - 8cm, 9.5 -21.05cm, and 100- 200g respectively while, that of Synodontis nigrita for TL, SL, BD, HL, IL, W and IL/SL values was from 9.3 – 24.9cm, 6.9 – 20.5cm, 2.7-12cm, 2.1– 6.8cm, 3.4–241.8cm and 20 - 450g respectively. The condition (K) -factor for both species showed were both above 1.0 indicating a healthy fish population and good growth conditions across the duration (P>0.05). The length-weight relationship showed that T. mariae was not highly regressed on length which depicted no significant difference (P>0.05), whereas S. nigrita was highly regressed on length (P<0.05) showing significant difference. The Coefficient of determination (R2 ) and the Correlation co-efficient (r) being 1 and 1 respectively for T. mariae and Synodontis nigrita. The growth coefficient (b) was 0.1443 and 3.1815 for T. mariae and Synodontis nigrita respectively. Body Length-Intestinal Length Relationship for T. mariae with coefficient (b) = 1.0565 been positively allometric was not significantly different (P>0.05), While S. nigrita with coefficient (b) =4.5123, also positively allometric was significantly different (P<0.05). Thus, the result shows the fishes were in good condition.
