Several physiological characteristics and housing conditions are known to affect hematologic and serum biochemical values in macaques. However, the studies that have been conducted either report values calculated based on a small number of animals, were designed specifically to document the effect of a particular condition on the normal range of hematologic and serum biochemical values, or used parametric assumptions to calculate hematologic and serum biochemical reference intervals. We conducted a retrospective longitudinal cohort study to estimate reference intervals for hematologic and serum biochemical values in clinically healthy macaques based on observed percentiles without parametric assumptions. Data were obtained as part of the Biomedical Primate Research Centre (Rijswijk, The Netherlands) health monitoring program between 2018 and 2021. In total, 4009 blood samples from 1475 macaques were analyzed with a maximum of one repeat per year per animal. Data were established by species, gender, age, weight-for-height indices, pregnancy, sedation protocol, and housing conditions. Most of the parameters profoundly affected just some hematologic and serum biochemical values. A significant glucose difference was observed between the ketamine and ketamine-medetomidine sedation protocols. The results emphasize the importance of establishing uniform experimental groups with validated animal husbandry and housing conditions to improve the reproducibility of the experiments.

This case describes a fibrosarcoma on the left upper leg of an adult female rhesus macaque. The patient was initially presented with a defined swelling at the caudolateral side of the upper leg. Medially from the growth, a swollen circular wound had formed with a fistula leading in the direction of the mass. The swelling was firm on palpation and was located in the subcutis, attached to the skin and underlying tissues. No other clinical abnormalities were observed. Treatment was initiated for an abscess with concurrent infection. Unfortunately, despite intensive wound debridement, wound lavage and antibiotic treatment, the growth did not resolve, and the animal was euthanased humanely due to clinical deterioration. Postmortem examination revealed a uniform, firm, white structure that had infiltrated deep into the underlying tissues. Histologically, the mass consisted of pleiomorphic spindle cells in fascicles with a collagenous stroma and negative desmin immunostaining, suggesting diagnosis of a fibrosarcoma.

This case represents the first reported use of Siemens Cios Spin mobile 3D C‐arm system for diagnostic imaging for a congenital cleft palate in an adult rhesus macaque ( Macaca mulatta ). This technology provided a versatile, rapid, and on‐site imaging modality with diagnostic value for craniofacial assessment that may also be applicable to other nonhuman primate species and the evaluation of additional anatomical structures.

Marmosets are routinely used in biomedical research, therefore there is an increasing need for updated reference intervals calculated using a large sample size, correct statistics, and considering different variables. Hematological and biochemical values from 472 healthy common marmosets sedated with alphaxalone were collected over a ten-year period (2013–2023). The variables assumed to have influenced the blood-based parameters were compared, i.e., sex, age, housing condition, pregnancy, and contraceptive use. Reference intervals were calculated based on observed percentiles without parametric assumptions, and with parametric assumptions following Box–Cox transformation. Juvenile marmosets showed increased ALP, phosphate, WBC, lymphocyte count, and basophil count and decreased levels of GGT and Fe compared to adults. Marmosets housed strictly indoors showed increased ALT and GGT levels and decreased levels of total bilirubin and neutrophil count compared to marmosets housed with outdoor access. Pregnant marmosets showed increased ALP, total bilirubin, neutrophil count, monocyte count, and basophil count, and decreased levels of AST, ALT, cholesterol, Fe, and lymphocyte count compared to non-pregnant marmosets. Etonogestrel contracepted marmosets showed decreased P-LCR compared to females who were not contracepted. Updated reference intervals will aid researchers and veterinarians in identifying physiological and pathological changes, as well as improve the reproducibility of research in this species.