Hatchery

A hatchery is the production unit where gametes from broodstock are fertilized and reared through the most fragile early life stages — egg incubation, hatching, yolk-sac absorption, first feeding, and larval rearing — until animals reach fry or fingerling size for transfer to nursery or grow-out. Hatchery work is intensive and unforgiving: eggs may number in the millions, and survival from egg to weaning is often just 30–60% even in well-run facilities. Critical control points include water disinfection and ozonation, temperature management within 0.5°C of target, live-feed production (rotifers, Artemia, copepods) for marine larvae, and continuous removal of mortalities and debris. Because larvae are immunologically immature, pathogen exclusion via SPF broodstock, egg disinfection, and strict biosecurity is essential; a single bacterial or viral introduction can destroy an entire cohort. For the industry, the hatchery sets the ceiling on farm performance — size uniformity, deformity rates, and disease status at stocking are all determined here. Modern hatcheries are increasingly recirculation-based, tying hatchery performance to biofilter and dissolved oxygen management.