Lozano, A., West, A., Leland, S. et al. 2010. Preventing boredom in NHPs using fleece fabric and food treats. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 15(5), page numbers missing.

Recently, I devised yet another way to use this fleece material to enhance the environments of our animals. To this end, I sought out a way to present food enrichment to our animals so that they would have to solve a problem to receive the food enrichment. To do this, I laid out one pre-cut square fleece blanket and sprinkled a birdseed trail mix in the center. Then, I placed a few grapes and slices of apple on top of the mix, and tied all of the four corners into two knots in the middle of the blanket. This created a small satchel that could easily be placed in the feeder hole of the cages. When the animals receive the satchel, they have to work in some way to get the knots out to receive the food enrichment. The scent of the fruits and birdseed trail mix, along with the odd shape, attracts the curiosity of the primates. An immediate desire to obtain the treats within can be observed. I now use many variations of the enrichment idea that I have created. Occasionally, I will cut a longer and narrower strip of fabric and create three separate knots with smaller amounts of food enrichment in each. The three knots require additional effort from the animal to receive their food enrichment, further alleviating boredom. It is so rewarding to see the animals find creative ways to untie the knots of the fleece material to receive their food enrichment. Once all of the treats have been removed, the primates have a piece of fleece they can manipulate as they choose.