Embryonic Development, Early Ontogeny and Reproductive Performance Across Successive Spawning Cycles in Tiger Barb (Puntigrus tetrazona)

Tiger barb (Puntigrus tetrazona) is an economically important ornamental cyprinid widely cultured in the global aquarium trade; however, comprehensive information on its early development and reproductive performance remains limited. This study characterized embryonic development, larval and juvenile ontogeny, and reproductive performance under controlled hatchery conditions. Fertilized eggs were continuously observed from fertilization to hatching using stereomicroscopy, while larval development was monitored from hatching to 30 days post-hatching (dph). Reproductive performance was evaluated across five consecutive spawning cycles by determining estimated mean egg production per stocked female, fertilization rate, hatching rate, and larval survival. At 26.5–27.5 °C, embryonic development progressed through cleavage, blastula, gastrula, neurula, and organogenesis, and hatching commenced at 25 h 10 min post-fertilization; approximately 50% of viable embryos had hatched by 27 h 17 min, and hatching was completed by approximately 35 h 28 min. Newly hatched larvae measured 3.88 ± 0.56 mm in total length, and complete yolk-sac absorption occurred at approximately 7 dph. Characteristic vertical body pigmentation appeared at 15 dph, whereas juvenile characteristics were evident by approximately 20 dph, while complete scale coverage and adult-like coloration were observed by 30 dph. Reproductive performance declined significantly with successive spawning events, with fecundity decreasing from 182.33 ± 1.57 to 64.33 ± 3.52 eggs female−1 between the first and fifth spawnings, accompanied by reductions in fertilization, hatching, and larval survival rates. These findings provide a morphological developmental reference and practical hatchery benchmarks that can support broodstock management, larval rearing, and seed production of tiger barb in ornamental aquaculture.