Related Experiment Video
Updated: Aug 14, 2026
Noninvasive, In-pen Approach Test for Laboratory-housed Pigs
Published on: June 5, 2019
Cage toys reduce abnormal behavior in individually housed pigtail macaques
1Department of Laboratory Animal Medicine, Southwest Foundation for Biomedical Research, San Antonio, TX 78245-0145, USA.
Abstract:
As part of a behavioral intervention program that identifies and treats individual nonhuman primates exhibiting abnormal behavior, five individually housed pigtail macaques (Macaca nemestrina) were provided with multiple cage toys in an effort to reduce high levels of abnormal behavior. Ten 30-min observations of each subject were conducted during the baseline condition and again after novel toys were presented, both loose inside the cage and attached to the outside of the cage. The new toys were used during 27% of the observation time. Kong Toys were used most consistently by the macaques during the 5-week observation period. Significant decreases in abnormal behavior and cage-directed behavior, as well as significantly increased enrichment use, were evident after the toys were added. Several of the toys were destroyed quickly, and individual differences were evident in the levels of enrichment use and abnormal behavior. Providing multiple manipulable toys as enrichment for pigtail macaques was effective in reducing abnormal behavior and was an important part of an environmental enrichment program for monkeys who could not be housed socially.
Insights
Providing new cage toys significantly reduced abnormal behaviors in individually housed pigtail macaques. This environmental enrichment proved effective for these nonhuman primates, enhancing their well-being.
Area of Science:
- Primate behavior and welfare
- Animal enrichment strategies
- Nonhuman primate behavioral interventions
Background:
- Individually housed nonhuman primates can exhibit abnormal behaviors.
- Behavioral intervention programs aim to treat such behaviors.
- Environmental enrichment is crucial for captive animals, especially those housed alone.
Purpose of the Study:
- To assess the effectiveness of providing multiple manipulable cage toys as environmental enrichment.
- To reduce abnormal behavior in individually housed pigtail macaques (Macaca nemestrina).
- To evaluate enrichment use and its impact on behavior.
Main Methods:
- Five individually housed pigtail macaques were observed before and after the introduction of novel cage toys.
- Observations recorded abnormal behavior, cage-directed behavior, and enrichment use.
- Toys were presented both loose and attached to the cage exterior.
Main Results:
- A significant decrease in abnormal and cage-directed behaviors was observed after toy introduction.
- Enrichment use significantly increased, with Kong Toys being favored.
- Some toys were quickly destroyed, and individual differences in response were noted.
Conclusions:
- Multiple manipulable toys are an effective environmental enrichment strategy for pigtail macaques.
- This enrichment can successfully reduce abnormal behavior in individually housed primates.
- Toy-based enrichment is a valuable component of welfare programs for nonhuman primates unable to be socially housed.
