Date of Award
Summer 8-2-2024
Document Type
Thesis
Degree Name
Master of Arts (MA)
Department
Psychology
First Advisor
Dr. Diana Reiss
Second Advisor
Dr Christopher Cheleuitte-Nieves
Academic Program Adviser
Dr, Diana Reiss
Abstract
Nonhuman primates housed in indoor laboratory environments are generally exposed to nondescript background visual stimuli. This environment is not ideal for species whose primary sensory modality is visual. To provide a more naturalistic visual environment that would potentially improve their welfare, this study assessed the efficacy of a passive natural visual stimulus in the reduction of stress and stereotypy and agonistic behaviors in a cohort of four (2 male, 2 female) Cynomolgus macaques (Macaca fascicularis) housed in an indoor laboratory facility in New York City. The macaques were exposed to four different videos depicting scenes of natural landscapes that were projected onto a 5’ by 10’ area of wall in their housing room. A different scene per week was projected from 7:00 – 18:00hr, seven days/week over the course of four weeks. Stress was assessed by comparing weekly urine cortisol:creatinine ratio levels and stereotypy and agonistic behaviors were assessed by recorded behavioral observations. Urine samples were collected in the morning from catch pans, once a week during three conditions: Enrichment Standard (4 weeks), Visual Enrichment (4 weeks) and Return to Enrichment Standard (4 weeks). The animals’ behavior was assessed via 50 video recordings made of each macaque. The macaques had a baseline urine cortisol:creatinine ratio of 1.3 x 10⁻⁴ ± 2.7 x 10⁻⁵ μmol/L (mean ± SE) during Enrichment Standard which increased to 1.7 x 10⁻⁴ ± 2.6 x 10⁻⁵ μmol/L during Visual Enrichment and returned to baseline levels of 1.3 x 10⁻⁴ ± 1.8 x 10⁻⁵ μmol/L during Return to Enrichment. There were no significant effects found when comparing group average urine cortisol levels between Enrichment Standard or Return to Enrichment Standard conditions and the Visual Enrichment condition or between subject sex. Behavioral analyses showed a significant decrease of stereotypy in the macaques as a group (p = .001) during and after the Visual Enrichment. Additionally, a decrease in agonistic behaviors occurred during the Visual Enrichment period but
data was insufficient for a statistical analysis. Notably an increase in positive social behaviors such as allogrooming, cuddling and playing occurred during the Visual Enrichment period (4 weeks) and the Return to Enrichment period (4 weeks). Given the lack of negative response (increased stress or agonistic behaviors; decreased positive or affiliative behaviors) to the novel Visual Enrichment and the evidence of positive response (decreased stereotypy and agonistic behaviors; increase of positive or affiliative behaviors), this visual enrichment is a low cost, low maintenance way to improve the lives of cynomolgus macaques housed in indoor laboratory environments.
Recommended Citation
Rodgers, Jeannine C., "Enhancing the Visual Environment of Indoor Housed Laboratory Cynomolgus Macaques (Macaca fascicularis) to Reduce Stress and Maladaptive Behavior" (2024). CUNY Academic Works.
https://academicworks.cuny.edu/hc_sas_etds/1240
Included in
Animal Studies Commons, Comparative and Laboratory Animal Medicine Commons, Other Social and Behavioral Sciences Commons