Systematic analysis of animal welfare research priorities reveals significant gaps in knowledge that limit evidence-based welfare improvement.
Welfare research investment should be guided by where knowledge gaps create the greatest impediment to evidence-based improvement. Fish and invertebrate welfare research is urgently underfunded given the billions of individuals involved. Positive welfare indicator research is needed to complete welfare assessment frameworks. Wild animal welfare research requires investment to address the largest category of animal suffering. Strategic philanthropic investment in these areas creates multiplied welfare impact through enabling better-informed interventions.