Hematology of a Semi-Free-Ranging Colony of Mandrills (Mandrillus sphinx)

Reference Intervals and Percentiles for Hematologic and Serum Biochemical Values in Captive Bred Rhesus (Macaca mulatta) and Cynomolgus Macaques (Macaca fascicularis)

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.

Role of Grooming in Reducing Tick Load in Wild Baboons (Papio cynocephalus)

Nonhuman primate species spend a conspicuous amount of time grooming during social interactions, a behavior that probably serves both social and health-related functions. While the social implications of grooming have been relatively well studied, less attention has been paid to the health benefits, especially the removal of ectoparasites, which may act as vectors in disease transmission. In this study, we examined the relationship between grooming behavior, tick load (number of ticks), and haemoprotozoan infection status in a population of wild free-ranging baboons (Papio cynocephalus). We found that the amount of grooming received was influenced by an individual's age, sex and dominance rank. The amount of grooming received, in turn, affected the tick load of an individual. Baboons with higher tick loads had lower packed red cell volume (PCV or haematocrit), one general measure of health status. We detected a tick-borne haemoprotozoan, Babesia microti, but its low prevalence in the population precluded identifying sources of variance in infection.

Clinical biochemistry and hematology of the elusive sun-tailed monkey (Cercopithecus solatus) in Gabon: inaugural data from the only semifree ranging colony in the world

Clinical blood biochemistry and hematology are valuable tools to evaluate health and welfare in many animal species. In order to document the general biology of one of the most poorly known nonhuman primate species, and contribute to its conservation, the clinical blood biochemistry and hematology of the sun-tailed monkey (Cercopithecus solatus Harrisson) was investigated in its range of endemicity in Gabon. Data derived from 26 years of clinical monitoring of the only semicaptive colony of this species in the world, housed at CIRMF (Franceville, Gabon), were analyzed in order to establish reference values of age-sex classes. Consistent with previous reports in other primate species, age and sex significantly affected a number of biochemical and hematological parameters in C. solatus. Hematological analyses demonstrated significant differences in red blood cells, hemoglobin (HB), and hematocrit (HT), with males showing significantly greater values than females. In contrast, neutrophil counts were greater in females. An ontogenetic effect was detected for HB, HT, eosinophil, and monocyte counts, while lymphocytes significantly decreased with age. Biochemical analyses also showed significant differences, with females displaying greater cholesterol and alanine aminotransferase levels. Increase in levels of blood urea and aspartate aminotransferase coupled with decrease in albumin in old individuals suggested declining kidney, liver, and muscle functions with age. Interspecific comparisons were conducted and the effects of the unique semifree-ranging setting on the validity and value of the results presented are discussed. The reference values established will be useful in further ecological, parasitological, and virological studies of the sun-tailed monkey.