Tilapia fingerling production — the phase from hatching to juvenile — involves intensive handling and stocking conditions that significantly affect both survival rates and fish welfare.
The fingerling phase involves repeated acute stressors including netting, grading, counting, and transport that compromise welfare even if survival rates appear adequate. Chronic crowding stress suppresses immune function and promotes aggression. Hormonal sex reversal raises welfare questions that are only beginning to be researched. Water quality — particularly ammonia, dissolved oxygen, and temperature — is often variable in intensive fingerling systems, and fish lack behavioral refuge from these stressors. Improving fingerling welfare through reduced handling, better water quality management, and lower stocking densities has the dual benefit of improving survival rates and productivity.