Effects of Diet and Social Housing on Reproductive Success in Adult Zebrafish, Danio rerio.

Zebrafish (Danio rerio) have proven their efficiency as an animal model for genetics and development, but their nutrition and housing requirements continue to elude researchers. Diet and housing density were predicted to affect weight change and reproductive success in 120 days postfertilization (dpf) zebrafish, and growth performance of their progeny. Fish were fed one of four diets, each utilizing a different primary protein source (fish meal [Zeigler™], algae, or insect), while being housed 3.3 or 6.6 fish/L for 3 weeks. Clutch size, viability, and larval development of their progeny were monitored out to 10 dpf. All diets were sent out for proximate nutrient analysis and fatty acid profiles to understand how diet compositions affect reproduction. We found that diet and housing proximity affected adult fish weight and larvae growth; diets composed of higher levels of protein and polyunsaturated fatty acids (specifically arachidonic acid [AA] and eicosapentanoic acid) allowed fish to gain weight and produce healthy larvae. Fish housed at higher densities produced smaller embryos, but larger larvae than those housed at lower densities. These findings imply that significant effects of a modified stimulus are exhibited after relatively short periods.