Medical procedures necessary for routine care can induce stress in both the veterinary and human clinical situations. In the research environment, nonhuman primates undergo procedures like physical examination, blood sampling, and intravenous drug or fluid administration either as a part of routine veterinary care or during the modeling of clinical disease and interventions under study. Behavioral management techniques, such as training for cooperation, allow caregivers to train primates to voluntarily engage in various medical procedures. This approach reduces stress and anxiety associated with necessary procedures, thereby enhancing efficiency and minimizing the invasiveness of medical care. Consequently, veterinary evaluation and care can be provided without compromise, resulting in enhanced clinical outcomes and overall better health. In this study, we explored the impact of the behavioral management program implemented at our center on a subset of animals undergoing routine veterinary care, focusing on the overall experience, including animal welfare, scientific rigor, and efficiency in terms of economics and time. We investigated its impact on key factors, such as the total procedure and recovery time, incidence of side effects, and welfare indicators, revealing a significant positive influence on animal care. Furthermore, through case studies, we illustrate how behavioral management facilitates timely medical care and monitoring, effectively mitigating stressors that could otherwise impair health and welfare, enabling the provision of care that would have otherwise been unachievable. A thoughtfully designed primate behavioral management program, integrating cooperation and participation with veterinary care, forms the cornerstone of superior animal welfare, enhanced clinical care, and more accurate scientific outcomes.

Weight change predicts mortality and graft loss in human kidney transplant recipients, yet post-transplant weight dynamics in nonhuman primate (NHP) transplant models remain poorly characterized despite their importance in preclinical immunosuppression and tolerance studies. By failing to account for demographic-specific growth patterns, static weight thresholds reduce interpretability and mask early biological signals of post-transplant morbidity. We analyzed 879 weights from 40 NHPs undergoing allogeneic kidney transplantation, with follow-up censored at 1-year post transplant. Expected post-transplant trajectories were estimated using demographic-stratified linear mixed-effects models with natural splines. Deviations from predicted trajectories defined pathologic weight loss. Associations with adverse events were evaluated using time-dependent cause-specific Cox regression. Expected trajectories differed significantly by age and species, with greater anticipated weight gain among younger animals. Each one-standard deviation decrease below predicted weight was associated with a two-fold increased hazard of adverse events. The model predicted pathological deviations before symptom onset and humane endpoints. Longitudinal weight trajectory modeling represents a computational modeling-based new approach methodology (NAM) that improves interpretability of preclinical weight endpoints. Defining risk relative to expected trends enables earlier and more precise prediction of adverse events, supports adaptive intervention including immunosuppression de-escalation and infection-directed management.

Anticoagulant and antiplatelet therapies are used to prevent life-threatening complications associated with thrombosis. While there are numerous clinical guidelines for antithrombotic medications, there is an incomplete understanding of whether these interventions yield similar effects in preclinical models, potentially impacting their predictive value for translational studies on the development of medical devices, therapies, and surgical techniques. Due to their close physiologic similarities to humans, we employed nonhuman primates (NHPs) using a reverse translational approach to analyze the response to clinical regimens of unfractionated heparin, low-molecular-weight heparin (LMWH) and aspirin to assess concordance with typical human responses and evaluate the predictive validity of this model. We evaluate activated clotting time (ACT) in nine rhesus and six cynomolgus macaques following the intraoperative administration of intravenous unfractionated heparin (100–300 U/kg) reflecting the clinical dose range. We observed a significant dose-dependent effect of heparin on ACT (low-dose average = 114.1 s; high-dose average = 148.3 s; p = 0.0011). LMWH and aspirin, common clinical antithrombotic prophylactics, were evaluated in three rhesus macaques. NHPs achieved therapeutic Anti-Xa levels (mean = 0.64 U/mL) and ARU (mean = 459) via VerifyNow, adhering to clinical guidance using 1.0 mg/kg enoxaparin and 81 mg aspirin. Clinical dosing strategies for unfractionated heparin, LMWH, and aspirin were safe and effective in NHPs, with no development of thrombosis or bleeding complications intraoperatively, postoperatively, or for prophylaxis. Our findings suggest that coagulation studies, performed as an integrative part of studies on biologics, bioengineered devices, or transplantation in NHPs, can be extrapolated to the clinical situation with high predictive validity.