The Effects of Salinity on Growth of Sword Tail, <i>Xiphophorus helleri</i> (Heckel, 1848)

Abstract

This study was conducted to evaluate effect of different salinities (0, 2, 4, 6 ppt) on growth and survival of sword tail, Xiphophorus helleri for 45 days. The species were taken from the water sources, which has the salinity of zero ppt in the experimental unit and then transferred to control and respective treatments(T1,2 ppt, T2, 4 ppt and T3, 6 ppt). Fifteen sword tail fish were placed in each aquarium (1.5x 1.0x 1.0 feet3). They were fed with commercial feed along with plankton up to satiation once in a day and individually weighed at an interval of 15 days. The highest final mean weight was recorded in T1 ( 1.17±0.09 mg) which was significantly (P<0.05) higher than control and other treatments. The final length of the sword tail reared in the control (4.45 ± 0.102 cm) and T1(4.45 ± 0.286 cm) was significantly different than other treatments T2(4.35 ±0.076 cm) and T3 (3.98 ± 0.119 cm). Survival was significantly different among the three salinity treatments (P<0.05). In conclusion, the species can grow well in water having the salinity of 2 ppt, but it can tolerate salinity of 6 ppt. These findings give us a lead to further upscale the study to understand the scope of culture of the ornamental species in saline affected areas.