PROJECT SUMMARY The California National Primate Research Center (CNPRC) has supported the production of Specific Pathogen Free rhesus macaques for HIV/AIDS research since 1990. The initial agents selected for exclusion included Simian Retrovirus (SRV), Simian Immmunodeficiency Virus (SIV) and Simian T Cell Lymphotrophic Virus (STLV), based on their potential to interfere with AIDS research studies. The SPF program also included Herpes B virus due to the risk posed by the presence of this virus in macaque tissue and body fluids to personnel working with rhesus macaques. Initial colony development was based on test and removal with a high frequency of testing to identity seropositive or virus- positive animals that had the potential to transmit the viruses in question. This created a colony of Specific Pathogen Free (SPF4) Indian origin rhesus macaques for AIDS research. The CNPRC has 24 half-acre field corrals that provide housing for the rhesus monkey breeding colony. Currently four are assigned to the U42 project to support the production of pedigreed SPF4 animals for AIDS research. Each of these field corrals can house approximately 150 animals but typically are formed with smaller populations of twenty males and fifty females. A typical breeding group consists of animals belonging to several age groups characterized by a strict dominance hierarchy. The CNPRC maintains detailed behavioral and social records of each social group to facilitate management decisions pertaining to breeding needs, research support and the colony’s wellbeing. Established matrilines along with several adult males provide social stability in the group formation and subsequent years. These animals are a long- term breeding resource and serve as a national resource for infants, juveniles, adults, and aged animals for use in biomedical research by investigators from throughout the United States. 18 of the existing field cages at the CNPRC already have steel overhead structures to protect the animals from the heat in the summer and the rain in the winter. Approximately 10 of these corrals were constructed in the 1970’s and have required repair and maintenance over the past 50 years. 6 of the corrals have either structural problems and/or deteriorating shade covers that were put in place to shelter the outdoor animals from both sun and rain. These canvas shade structures are damaged by wind and the sun and need replacement every few years. The requested funds will help purchase one steel overhead shelter for one of the corrals. This project will purchase a replacement 19' high, 100’ wide, and 60’ long steel-frame canopy covers (similar to patio structures) that will cover approximately one-quarter of a corresponding half-acre field corral, or 6,000 square feet. The structures will include steel framing, metal roofing, and concrete footings. Each structure has a life span of 50 years. Depending on the corral population each corral can produce between 25 to 35 infants per year...