The implementation and initial evaluation of a physical therapy program for captive chimpanzees (Pan troglodytes)

Area of Science:

• Veterinary Medicine
• Primatology
• Animal Welfare Science

Background:

• The captive nonhuman primate (NHP) population includes a growing number of geriatric chimpanzees (≥35 years old).
• Geriatric chimpanzees often experience age-related conditions like arthritis, stroke, and mobility impairments.
• Existing welfare programs for geriatric chimpanzees lack robust empirical evaluation of their efficacy.

Purpose of the Study:

• To develop, implement, and assess the impact of a physical therapy (PT) program on the physical health, mobility, welfare, and behavior of geriatric chimpanzees.
• To evaluate the effectiveness of PT interventions in improving the quality of life for aging chimpanzees in captive environments.

Main Methods:

• Nine mobility-impaired chimpanzees participated in personalized, positive reinforcement-based PT sessions twice weekly for five months.
• A control group of nine age- and gender-matched, non-mobility-impaired chimpanzees engaged in body exam behavior sessions.
• All chimpanzees were assessed on 14 health, well-being, and behavior items, alongside mobility levels throughout the study.

Main Results:

• Chimpanzees in the PT program demonstrated significant improvements in physical health, well-being, and activity levels.
• Compared to controls, PT participants showed notable increases in ease of movement ratings.
• Rater bias was a limitation, indicating these findings are an initial evaluation.

Conclusions:

• Participation in the physical therapy program appears to confer physical, behavioral, and welfare benefits to geriatric chimpanzees.
• The study highlights the necessity of assessing novel, geriatric-focused care strategies to improve captive chimpanzee welfare.
• As the proportion of geriatric animals increases, such programs are crucial for their long-term care.