This study investigated the teratogenicity of ethanol in several different strains of chickens. The chick embryo provides a useful model for studying the fetal alcohol syndrome. Two broad classifications of chicks, each containing many strains, are commercially available for use: broilers and layers. Teratogenicity of ethanol in broilers and layers was studied by examining three different parameters: embryo weight, ratio of torso weight to head weight, and embryo viability. Broilers and layers experienced similar ethanol-induced reductions in embryo weight, Broiler embryos experienced a preferential ethanol-induced suppression of head growth. Differences in viability between different strains were found, but no clear pattern between broilers or layers could be determined, possibly due to environmental conditions. The data presented here suggest that the strain of chick and the handling of the eggs are important considerations when studying the teratogenicity of ethanol. An ethanol dose-response test should be periodically performed as a check on environmental conditions affecting the eggs--conditions that are beyond the control of the researcher.