Extinction probabilities of Jordan indigenous cattle using population viability analysis

摘要

Estimation of expected loss of genetic diversity in a population or breed within a defined future time horizon requires initially population viability analysis (PVA). The PVA needs estimates of probability of extinction (PE). In this study, the PE of Jordan indigenous cattle breed was simulated by PVA using Vortex (R) modeling program. The annual numbers of recorded cows, bulls and their progeny were used as census data. Using the census data, effective population size (N-e) was calculated and found to be almost half (N-e = 40) of what is recommended (N-e = 82) by FAD [FAO, 1995. World Watch List for Domestic Animal Diversity. 2nd Ed. Rome, Italy] to escape endangerment. Furthermore, the EP, growth rate, heterozigosity and inbreeding rate were simulated using the PVA for a past and future time horizon. The estimates of EPs were sensible and depended heavily on the time horizon, physiological parameters and catastrophic events considered. The catastrophes were exotic breed competition and drought of 25% severity each on the population living. The model concludes that. while perhaps more or less variation in simulated population dynamic compared to real population dynamic in the past, the simulation was a fairly simulation of the likely fate under assumed living conditions. Further, the future simulated model concluded that the population is currently expected to decline rapidly toward extinction within the coming 10 years considering the same assumed conditions and absence of conserving genetic program. In such situation, it is recommended that an ex-situ live conservation program can only be a successful tool to conserve this endangered breed.