Optimizing mating strategies to maximize genetic diversity in the mhorr gazelle (Nanger dama mhorr) ex situ breeding program

To minimize coancestry among the offspring by equalising parents' contributions is currently one of the most widely used methods to maximize the genetic diversity in conservation programs of threatened species. The objective of this study was to compare the performance of 22 different mating strategies to limit the loss of genetic diversity in a real captive population of mhorr gazelle (Nanger dama mhorr) via computer simulations. This objective was achieved by monitoring the evolution of the effective population size (Ne) throughout 15 generations. The studied population consisted of 87 breeding animals (25 males and 62 females), from a total pedigree of 3059 records. The scenarios were designed according to different assumptions: the use of parents coancestry or offspring coancestry, the use of the coefficients themselves in calculations or their increases, and the number of males and females involved in the mating. The results for this captive population showed that strategies to minimize the parent's coancestry were the best in the short term, but mixed strategies to minimize coancestry of both parents and offspring were better in the medium and long term when a weight to coancestry in the parents' generation between 5% and 50% was applied. Furthermore, it was observed that these mixed strategies improved their performance when all females in the population participated in breeding, but not all males. These results suggest that each managed population may need different mating strategies, considering its generation interval, the species' breeding system, the expected time horizon of the conservation program, or other species-specific considerations of the population.