Evaluation of growth performance and stock variance of common carp, Cyprinus carpio in inland saline aquaculture system

Aim: This study examined the growth performance of six geographical stocks of common carp, Cyprinus carpio a species that tolerates salinity up to 10 ppt, in saline water systems. Methodology: Two growth experiments were conducted under low salinity (S1: 2-4 ppt) and high salinity (S2: 8-10 ppt) levels. In the first experiment (1-225 days), six stocks (MH, MN, TR, MP, HR, AP) were housed separately, and traits like body weight, length, and height were recorded. In the second experiment (225-365 days), fish were tagged and communally reared, with males and females kept separately. Results: Significant variations in Body weight (Bw), Body length (Bl), and Body height (Bh) were observed among the stocks in the first experiment, with the MH stock performing best. In the second experiment, the least squares means of Bw was 354.59±10.04 g in S1 and 335.99±10.12 g in S2. The effect of Bw at tagging, salinity and sex by salinity interaction had a significant effect on Bw and Bh. Females in the S1 group exhibited the highest growth metrics (376.19±10.39 g, 21.39±0.43 cm, and 8.23±0.10 cm for Bw, Bl and Bh, respectively). Heritability estimates for growth traits (Bw: 0.11 ± 0.06; Bl: 0.12 ± 0.07; Bh: 0.11 ± 0.06) indicated moderate genetic variability, supporting the potential for a selective breeding program to develop fast growing common carp for inland saline aquaculture. Interpretation: The study demonstrates the potential of selective breeding in common carp to culture in saline environment, offering a sustainable solution for utilizing degraded saline soils. Key words: Common carp, Growth performance, Inland saline aquaculture, Salinity tolerance