RESUMEN
BACKGROUND: Regarding the good practice in the laboratory work, it is essential to have a broad spectrum of biochemical and hematological references in pregnant females to determine the health status of the colony. OBJECTIVE: To establish reference values to reveal changes in hematology and blood chemistry in pregnant rhesus monkeys (Macaca mulatta) in their first trimester of pregnancy. METHODS: Twenty-eight females in reproductive stage were used, divided into two groups: 14 pregnant macaques in their first trimester and 14 non-pregnant used as the control group. Blood samples were collected for the hematological test and blood chemistry. RESULTS: The results showed significant difference in the blood chemistry for the following parameters: glucose, total bilirubin, and total protein. The hematological evaluation revealed significant difference in leukocytes and neutrophils. CONCLUSIONS: These findings offer a reference range and provide a basis for improvement in techniques and refinement of clinical processes in these specimens.