ABSTRACT Freshwater ecosystems across South Asia face increasing pressure from anthropogenic activities, with rheophilic fishes particularly vulnerable due to specialized habitat requirements and reliance on seasonal migrations. Labeo dero (Hamilton 1822), a declining rheophilic cyprinid, represents both a conservation priority and a candidate for aquaculture diversification. We conducted the first comprehensive reproductive biology characterization and comparative hormonal induction trials for this species in Bangladesh, providing a foundational framework for conservation aquaculture. Seasonal monitoring of 180 broodstock revealed a unimodal breeding peak in July, with female gonadosomatic index (GSI) reaching 14.9% and fecundity showing positive allometry. Dose–response experiments established optimal induction at 6 mg/kg (♀) and 3 mg/kg (♂) for carp pituitary gland (CPG) and 0.6 mL/kg (♀) and 0.3 mL/kg (♂) for Ovuhom, yielding spawning success of 94.7% and 82.3%, respectively. Three‐parameter logistic (3PL) regression yielded a reliable ED 50 of 4.04 mg/kg for CPG. For Ovuhom, although a clear dose‐dependent response was confirmed, ED 50 estimation was less robust due to limited dose spacing, and this value should be considered preliminary. Comparative analysis indicated broadly similar efficacy, though the results should be considered preliminary due to limited replication ( n = 3 per treatment), which constrained statistical power. CPG demonstrated numerically shorter latency (9.7 vs. 11.0 h) and higher spawning rates, but formal equivalence testing was inconclusive due to insufficient sample size. This work provides a practical, evidence‐based hatchery protocol to support captive breeding efforts. While preliminary, these findings offer a critical foundation for conservation aquaculture and a transferable model for other data‐deficient hillstream species in South Asia.
Ahamed et al. (Thu,) studied this question.