Effect of thyroxine hormone towards growth and survival of climbing perch (Anabas testudineus, Bloch) larvae

Aim: Climbing perch (Anabas testudineus) is a popular fish in Asian countries. However, the long culture period and slow growth of the species has made it unpopular among fish farmers. Thyroxine (T-4) is a hormone that functions as a growth precursor in all mammals including teleosts. This research aimed to study the effect of T-4 on growth and survival of climbing perch. Methodology: Larvae of climbing perch were used to perform the experiment at different frequencies of T-1 treatments (Group 1:1 X0.5 ppm T-4; Group 2: 2X0.5 ppm T-4; Group 3: 3X0.5 ppm T-4 and Group 4: control, 0 ppm T-4), by using immersion technique for 30 min. Treatments were performed once a week for three continuous weeks. Results: The highest survival of larvae was recorded from Group 2 (66.7%) as compared to control group (52.5%). The length and weight of fish treated with T4 showed significant increment (p