Growth performance of hatchery-reared mahseer (Tor soro) based on different cultural periods

Abstract

This study was carried out to evaluate growth performance, length-weight relationship, and condition factors of mahseer based on different culture stages. Fish larvae were produced by artificial spawning and reared in indoor tanks. Fingerlings were stocked in three replicate concrete ponds, fed with commercial pellets, and sampled within 4, 6, 12, and 24 months. In the first six months, the growth of fish increased much slower than in the 12 and 24 months of cultures. There were no significant differences in total weight at six months of culture (p>0.05) compared with two and four months. Fish started to grow significantly different from 12 and 24 months of culture periods (P<0.05). The specific growth rate in the four-month culture was 2.01±0.40 (%) and slightly increased in six-month culture periods (2.10±0.22%), but it started to decrease with increasing the day of culture (12 months : 1.58±0.09% and 24 months: 1.13±0.04%). Negative allometric trends (b<3) were implied for all stages, but a high correlation occurred in the 12 and 24-month rearing periods with the equation W=0.331×L1.527 and W=0.375×L1.332, respectively. The condition factor ranged from 0.99 to 1.04, indicating fish tend to be poor, long, and thin.