Selective breeding programs for tilapia have produced fish with dramatically improved growth rates. Understanding the welfare implications of genetic improvement programs guides more balanced approaches to aquaculture genetics.
Tilapia selective breeding welfare mirrors broiler chicken genetics in miniature: selection primarily for production traits has delivered impressive productivity improvements but may have created fish who are more susceptible to the welfare-compromising conditions of intensive culture. Fast-growing strains that show reduced immune function are more vulnerable to disease in crowded pond conditions, requiring more frequent health interventions. The hormonal sex reversal of female fingerlings to produce monosex male culture involves brief exposure to testosterone-laced feed — a practice that is effective for production purposes but raises welfare questions about the hormonal manipulation of developing fish. Future welfare-conscious breeding programs should incorporate immune function, stress tolerance, and behavioral health metrics alongside growth and disease resistance as selection criteria.