Meeting Abstract
In the mid-1980’s, the last remaining black-footed ferrets (Carnivora: Mustelidae: Mustela nigripes), an obligate carnivore that feeds on prairie dogs throughout North America’s Great Plains, were removed from the wild to initiate a captive breeding program to save the species from extinction. After more than 30 years of captive breeding (starting with 7 founders), the rate of reproductive failure has increased from 20-30%, to nearly 70%. This reduction could be attributed to declining semen quality in males and/or the increased rate of ovulation failures in females. Moreover, because the baculum plays an important role in semen deposition and the degree of stimulation of the female reproductive tract (induced ovulation), its morphology provides information on male quality and female mate choice. Consequently, we wanted to determine if the baculum shape and size had changed over the duration of the breeding program, thereby potentially influencing reproductive success. Hence, we measured 50 bacula from captive adult ferrets born between 1993 and 2007, and obtained siring histories (studbook records) and semen data from 27 of these males. With no novel genes to bring into the population (naturally), inbreeding coefficients (F) will continue to increase over the years. Not surprisingly, we found that as the male F increased, the number of kits sired declined. Ferret body length was not related to baculum size and shape. However, we found that the baculum base width declined over time, while baculum length remained the same. The thinning baculum base was not directly linked to reproductive success in these males. Next steps are to continue measuring bacula from historic and modern specimens as a comparison between wild and captive born ferrets to further explore the role of the captive environment on the baculum morphology.
