EVALUATION OF SPAWNING PERFORMANCE IN Anabas testudineus (BLOCH, 1792) BY SERIAL DILUTION OF sGnRHa WITH NORMAL SALINE

Anabas testudineus also known as climbing perch is an air-breathing fish, which can survive in low DO concentrations. It is an important food fish in India and has a good consumer preference. The breeding protocol was standardised for this fish but the hormone requirement for induced breeding was much higher. So, the present study was conducted to reduce the hormonal requirements and hence reduce the hormonal cost. The sGnRHa was serially diluted with normal saline in a ratio of 1:0.5, 1:1, 1:1.5, 1:2 and 1:0 v/v (Table. 1) which served as T1, T2, T3, T4 and control respectively. Mature males and females were selected based on their secondary sexual characters (Fig. 1 & 2) and are stocked in 200L capacity FRP tanks. In every treatment one female and two males were stocked. The females were administered with 0.75µl/g BW and the males were administered with half the dose of females. The greatest (P<0.05) relative fecundity (532 ± 15 eggs/g BW), fertilization rate (95.5 ± 6%)  and hatching rate (94.93 ± 7.3%) was observed when the brooders were injected with 1:1.5 hormonal dilution. The treatment T4 showed the lowest spawning performance in comparison to the other treatments. Hence, the study indicated that the dilution of sGnRHa with normal saline in a ratio of 1:1.5 and injecting with 0.75µl/g BW resulted in effective spawning in climbing perch, which not only reduces the hormonal doses but also reduces the hormonal cost expenditures.