Swiss Webster pups were fathered by sires given either an acute dose of alcohol (alcohol-sired) or saline (saline-sired) 12-24 h before mating. The same sires were used to father both groups of pups. Alcohol-sired pups were significantly lighter at birth and for the following three weeks than were saline-sired pups. Significantly more pups were fathered by saline-exposed sires, and dams carrying those pups had significantly longer gestations than those carrying pups of alcohol-using sires. More runts were born to the alcohol-sired group, and more pups in that group died over the next three weeks than in the saline-sired group. Significantly more pups in the saline-sired group achieved such developmental milestones as surface righting, clinging, the tail-pull reflex, rotation, linear movement and climbing an inclined surface earlier than did alcohol-sired pups. As adults, animals from the alcohol-sired group showed significantly less risk assessment behavior and longer latencies to such behaviors as stretched attention, flatback, freezing and defensive burying than did the saline-sired animals. Alcohol-sired animals contacted the stimulus object in the risk assessment test significantly sooner and more often than did the saline-sired group. In tests of aggression, alcohol-sired male offspring showed more frequent aggressive behaviors such as on-top, lateral attacks and jump-attacks, and significantly fewer defensive/fearful behaviors such as piloerection, tail rattling and jump-escape. This pattern of results suggests that exposure of the sire to one acute dose of alcohol before insemination caused some early developmental delays and that alcohol-sired animals are less fearful and more aggressive as adults than saline-sired animals.