Rhesus macaques and SIV infection.

Thirty-nine infant rhesus macaques specific pathogen free for SIV, type D simian retrovirus, herpes B virus, and simian T-cell leukemia virus type 1 from the Tulane National Primate Research Center were used in this study (Table 1). Newborn macaques were removed from their mothers, reared in an animal biosafety level 2 (ABSL2) nursery, and studied in accordance with the standards of the Guide for the Care and Use of Laboratory Animals (62) and with approval by the Institutional Animal Care and Use Committee of Tulane University. Animals were inoculated intravenously with 100 50% tissue culture infective doses (TCID₅₀) of SIV_mac251 within 24 h of birth (n = 15) or between 53 and 105 days of age (n = 4). Humane euthanasia was conducted at the scheduled time points and/or when warranted by manifestations of clinical AIDS or morbidity as indicated in Table 1. Neonates were defined as less than 1 month of age, and infants were defined as less than 1 year old.