Computed tomography is a feasible method for quantifying bone density in Macaca mulatta.

Osteopathologies are a result of advanced age and decreased bone density and represent a global health problem. It is therefore important to generate models for longitudinal studies of the pathophysiology in order to improve early diagnosis and develop preventive therapies. For this kind of research, the use of computed tomography (CT) to evaluate bone health offers advantages over other techniques since it provides more complete information. The aim of this prospective, pilot study was to obtain measurements of the left femur from a population in captivity of 32 rhesus monkeys (Macaca mulatta) in order to standardize the model for future research. Healthy subjects from 5 to 28 years old were chosen. Three groups with different ages were formed as follows: (1) 5-9 years, (2) 10-19 years, and (3) 20-28 years. Semi-automatic segmentation by threshold defined the regions of interest, which were subdivided in the range of 300-700 Hounsfield units (HU) for trabecular bone and >700 HU for cortical bone. Then, the proportional ratios of the volumes of trabecular bone and cortical bone were obtained. Significant differences (analysis of variance test) in the averages of Hounsfield units, cortical, and trabecular bone proportions from each age group proved that a decrease in bone density begins at approximately 20 years of age. The values presented here, as well as the method to obtain them from CT scans, can be used as a baseline in a primate model for long-term research in bone pathology diagnosis and treatment.

Absence of the right wing of the ilium generated a compensatory scoliosis in rhesus monkey in captivity: diagnostic imaging and its alteration on the SEPNT.

BACKGROUND: Congenital scoliosis (CS) is defined as lateral curvatures of the spine provoked by the anomalous development of the vertebral bodies. It is associated with neuromuscular anomalies, which can be genetic, caused by the compensation of discrepancies in the length of the extremities or intrarachidian anomalies. METHODS: This study was carried out in 2-year-old female, showed alterations in the gait, mainly in the hind limbs, a clumsy gait and a slight claudication in the right hindlimb. To perform the imaging study were: X-Ray projections and Computerized Axial Tomography, neurophysiological evaluation was performed by means somatosensory-evoked potentials of the tibial nerve (SEPTN). RESULTS: The results showed an enlargement of the latencies from the L5 to the cortex, mainly in the left afference, correlated with the imaging studies. CONCLUSIONS: There is no doubt that the concurrent use of different diagnostic tools complements knowledge regarding the physiopathogenesis of these osteopathologies.

Changes in blood parameters in rhesus monkeys (Macaca mulatta) during the first trimester of gestation.

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.