Description: This core provides the following: 1) breeding and husbandry, 2) studies developmental progress in individuals, 3) consultation for core users, 4) training for user personnel, 5) develop normative standards of development for comparison, 6) experiments on husbandry improvements, and 7) provide innovative responses to user needs. In addition to the service component, the laboratory conducts research on the influence of husbandry practices and reproductive history on pregnancy outcome and infant characteristics. In addition IPRL collaborates on research that uses these endpoints along with intervention variables associated with specific research hypotheses. The laboratory supports seven NIH-funded projects with seven different principal investigators in four of the six research programs of the MRRC.