Spawning biology, breeding, and larval rearing techniques for Xenentodon cancila (Hamilton) for aquaculture and recreational use in Bangladesh: The first approach

Abstract

The study examined Xenentodon cancila (Hamilton) breeding biology, reproduction, and larval rearing. In this study, gonadosomatic index (GSI) and fecundity were measured for breeding biology every 15 days. Nine doses of common carp pituitary gland (CPG), human chorionic gonadotropin (HCG), and Ovaprim for breeding were administered, except in the control treatment that was without hormones. Mustard oil cake (D1), powdered feed (D2), and one-day-old live tilapia (Oreochromis sp.) larvae (D3) were used to determine larval survival after 28 days. From the end of May to mid-July, the mean GSI value exceeded 15 ± 0.72%, peaking at 16.02 ± 1.28% in June. Mean fecundity ranged from 110 ± 13.34 to 2961 ± 318.57, peaking at the end of June 2019, which indicated that this was the peak breeding season for X. cancila. The best spawning was with CPG at 20 mg kg^-1 fish body weight (BW) and Ovaprim at 1.0 ml kg^-1 BW, but the control group (B) and the group administered 500 IU kg^-1 HCG (H1) did not spawn. Latency and hatching periods were 19-21 and 260-288 h, respectively. The highest fertilization, hatching, and survival rates were 92 ± 4.63%, 69 ± 5.52%, and 66 ± 4.11% with 20 mg kg^-1 CPG (C2), while the next closest value was recorded with 1.0 ml kg^-1 Ovaprim (O2). After 28 days, D3 had the highest survival rate (47.5 ± 4.62%), followed by D2 (31 ± 2.42%), and D1 (18 ± 1.54%). The findings will be useful for hatcheries, fish farmers, the ornamental fish sector, and biodiversity protection.