African wild dogs live in highly social and hierarchical groups. However, intra-pack aggression, injuries and even mortalities may occur during temporary separation of individuals from the pack, during new pack formations and after translocation events both in captive and free-living animals. Pheromones are naturally occurring chemicals that are released by one animal that act to control the behaviour or physiology of another animal of the same species. Appeasing pheromones have been found to be secreted by a number of different mammalian species. These pheromones have been found to reduce fear and stress behaviours in domestic dogs and offer a natural approach to moderate stress and aggression in African wild dogs. Previously, we tested domestic Dog Appeasing Pheromone (DAP; AdaptilTM, CEVA) to alleviate stress and subsequent aggression. We found that DAP did not appear to change stress hormones, but did reduce the aggression hormone, testosterone, after stressful events. DAP-treated animals also showed less contact dominance and active submission behaviours, with a shift toward non-contact dominance behaviour.
While pheromones of one species may be detected by another species that is closely related, these chemical odours are thought to be highly species-specific. As such, treatment with a domestic dog appeasing pheromones may not have as strong a beneficial effect on physiology and behaviour in African wild dogs as desired. The beginning of 2020 has brought a new face to the team to investigate whether an African wild dog-specific appeasing pheromone will be better at reducing stress and aggression during conservation interventions in this highly endangered species. Importantly, a reduction in these two behaviours can improve pack bonding and survival, by bolstering the immune system against disease threats like canine distemper, rabies and parvovirus.
Pia Riddell, our newest PhD student to join the team, completed a university degree in behavioural psychology at Edith Cowan University, Western Australia then moved to South Australia to pursue her passion for a career in wildlife conservation and reproduction by completing a degree in Animal Science, at the University of Adelaide. In 2019, she completed honours degree working with Merino sheep to determine how stress hormones and immune molecules transferred in milk within the first 24 hours after birth influenced neonatal lamb behaviours and survival. Now a PhD student at James Cook University in Queensland, Pia is using her time constructively during the Covid-19 shutdown to develop this new project in collaboration with Research Institute in Semiochemistry and Applied Ethology (IRSEA; France) and Wild dog Advisory Group (WAG; South Africa), and will be travelling to France to begin isolation of African wild dog appeasing pheromone candidates once international travel resumes.