Effect of pheromones on wild pig and peccary breeding success

Red River HogsRed River Hogs (Potamochoerus porcus) while not endangered are considered a Yellow Species Survival Program in zoos within the Association of Zoos and Aquariums (AZA). The reasons behind this program designation relate to over-representation of some founder animals and under-representation of other founder animals within the population. Such genetic distribution results in overall loss of gene diversity within the AZA population. This loss of gene diversity is due primarily to sporadic breeding within the population wherein some pairs of animals breed well, some do not and some breed well initially and then stop breeding in subsequent years.  The traditional approach to the management of this and many other zoo species has been to move non-breeding animals around to make new pairs in the hope that this would stimulate them to breed.  However, data within Red River Hogs suggests that movement and introduction of new animals has not improved reproductive rates in this species.

In primate species, pheromones have been shown to stimulate estrous cyclicity and libido. This research project examines the effect of introduction of novel pheromones (urine) versus novel animals on fecal steriod metabolite concentrations, behavior and estrous cyclicity in captive, female Red River Hogs (Potamochoerus porcus). We hypothesize that introduction of novel boar pheromones will stimulate estrous cyclicity in females and introduction of novel sow pheromones will stimulate increased libido in males.

We also are funded by the American Association of Zoo Veterinarians Wild Animal Health Fund to retrospectively examine the effects of age, parity and contraception use on reproductive tract lesions in male and female Suidae (pig) and Tayassuidae (peccary) species. This project is in collaboration with Drs. Dalen Agnew of Michigan State University and Anneke Moresco of Denver Zoo.

Dr. Newell-Fugate in her capacity as the reproductive advisor to the Association of Zoos and Aquariums Wild Pig, Peccary, and Hippo Taxon Advisory Group (TGA) consults on cases of reproductive infertility and contraception in captive Suidae and Tayassuidae species.  Her laboratory also runs fecal steroid profiles for these species on a contract basis.