Testing the effect of medical positive reinforcement training on salivary cortisol levels in bonobos and orangutans.

The management of captive animals has been improved by the establishment of positive reinforcement training as a tool to facilitate interactions between caretakers and animals. In great apes, positive reinforcement training has also been used to train individuals to participate in simple medical procedures to monitor physical health. One aim of positive reinforcement training is to establish a relaxed atmosphere for situations that, without training, might be very stressful.

Measurements of salivary alpha amylase and salivary cortisol in hominoid primates reveal within-species consistency and between-species differences.

Salivary alpha amylase (sAA) is the most abundant enzyme in saliva. Studies in humans found variation in enzymatic activity of sAA across populations that could be linked to the copy number of loci for salivary amylase (AMY1), which was seen as an adaptive response to the intake of dietary starch. In addition to diet dependent variation, differences in sAA activity have been related to social stress.

Stress affects salivary alpha-Amylase activity in bonobos.

Salivary alpha-Amylase (sAA) is a starch digesting enzyme. In addition to its function in the context of nutrition, sAA has also turned out to be useful for monitoring sympathetic nervous system activity. Recent studies on humans have found a relationship between intra-individual changes in sAA activity and physical and psychological stress.

Effect of giving birth on the cortisol level in a bonobo groups' (Pan paniscus) saliva.

This study documents the cortisol levels in the saliva of a bonobo group, especially that of a bonobo female which had given birth for the first time. During a long study in Zoological Garden Frankfurt, Germany, a bonobo baby was born on 3 August 2007. Due to the fission-fusion keeping system employed, the bonobos were divided into two groups on this day.