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Abstract The aim of this work was to compare costs, in the horse, cattle, sheep, swine, and rabbit species, for the creation of gene banks for reconstruction of an extinct breed, using different strategies: embryos-only, embryos in combination with semen, and semen-only. Three cost measures were used: time required for population reconstruction, cost for creation of the gene bank, number of years-keeping-female to reach reconstruction. Semen costs were estimated across four scenarios: the presence or absence of a commercial market for semen, purchase of semen donors, and semen extracted from the epididymus. The number of cells were doubled to take into account the creation of two storage sites. The strategy embryos-only required the shortest time to reach reconstruction. With the strategy embryos + semen, time increased with decreasing proportions of embryos. With semen-only, reconstruction time varied from 2 to 21 years. A high variation of costs was observed across species and strategies, from 360 Euros in the rabbit to 1 092 300 in the horse. In all species, the embryos-only strategy was about 10% more expensive than using 90% embryos + semen. Decreasing the percentage of embryos further diminished costs. The number of years-keeping-female ranged across strategies, from 2 in the rabbit, to a maximum of 12 878 in the horse.

Abstract The objective of this empirical simulation study was to evaluate the use of a combination of semen and embryos in the creation of gene banks for reconstruction of an extinct breed. Such an approach was compared for banks with varying proportions of embryos on the basis of the amount of the material to be stored, time for reconstruction, maintenance of genetic variability, and probability of failure during reconstruction. Four types of populations were simulated, based on reproductive rate: single offspring, twinning, enhanced reproduction, and litter bearing. Reconstruction was simulated for banks consisting of different combinations of semen and reduced numbers of embryos (expressed as a percentage of the material needed for a bank containing exclusively embryos and ranging from 10 to 90%). The use of a combination of semen and embryos increased the number of insemination cycles needed for reconstruction and the level of genetic relatedness in the reconstructed population. The risk for extinction was unacceptably high when a very low proportion of embryos (< 20%) was used. However, combining semen with embryos could decrease costs, allowing for the conservation of more breeds, and specific strategies for semen use could decrease the level of relationships in the reconstructed breed.

Simple Summary: Small populations can suffer from high inbreeding rates and the associated loss of diversity, inbreeding depression, and expression of genetic defects. Two questions are important for population managers in this respect: (1) What is the status of my population regarding inbreeding? and (2) what is the effect of measures to decrease inbreeding rates? The Retriever and Pointer software has been developed to answer these questions. Retriever extracts relevant data and inbreeding levels from studbook data and Pointer simulates populations to indicate what the effect is of different forms of genetic management. This paper describes the software and gives examples of its use. The Retriever and Pointer software has been developed for genetic management of (small) captive populations The Retriever program uses as input pedigree data and extracts data on population structure that determine inbreeding rates such as skewness of sire contributions. Levels and rates of inbreeding and kinship and effective population sizes are determined as well. Data on population structure can be used as input for the Pointer program. This program uses stochastic simulation to evaluate a population and provides expected levels and rates of inbreeding and kinship, and optionally allelic diversity. The user can simulate different options for genetic management such as sire restrictions, restrictions on inbreeding levels, mean kinships and breeding circles. Both Retriever and Pointer can analyze populations with subpopulations and different rates of exchange between them. Although originally devised for dogs, the software can be, and has been, used for any captive population including livestock and zoo populations, and a number of examples are provide The pointer software is also suitable in education where students may generate their own populations and evaluate effects of different population structures and genetic management on genetic diversity. Input is provided via a graphical user interface. The software can be downloaded for free. [ABSTRACT FROM AUTHOR]

Simple Summary: Maintaining minimum population sizes for local livestock breeds is a key goal in the conservation of animal genetic resources. As markets and livestock production systems have tended to favour a narrow base of high-output improved breeds, countries have had to use financial and other incentives to motivate breeders to keep local breeds. This paper explores the potential for more cost-effective alternatives to the most commonly used financial incentive, a fixed payment per animal or livestock unit. We compare the current fixed payment incentives for local breeds under the Slovenian Rural Development Programmme with those instead determined through a competitive tender approach. A stated preference survey was realised to determine the conditions under which breeders would be willing to participate in such an incentive system based on differentiated payments. Willingness to accept (WTA) payment for conservation was found to differ significantly from actual payment levels, being lower for the local sheep and goat breeds, and higher for the local pig breed. This suggests that implementation of differentiated payments would be more cost-effective; particularly when accompanied by measures to streamline administrative requirements, improve access to breeding stock and target support for local breed market valorisation (e.g., promotion of value chains based on designated quality schemes). Local livestock breeds in Slovenia have been eligible for financial incentives in the form of a fixed payment per livestock unit (LU) since 2002. The scheme has however not been successful in reversing the erosion of animal genetic resources (AnGR). This paper investigates an alternative, whereby incentive payments would better reflect breeders' actual opportunity costs. The paper contributes to the limited existing body of knowledge related to the use of tender mechanisms in the design of the payments for agrobiodiversity conservation schemes (PACS), particularly for AnGR. Empirical findings draw on the results of a stated preference survey involving 301 farmers in Slovenia, engaging, or being potentially able to engage, in the rearing of local pig, sheep and goat breeds. Interval and logistic regression model results suggest that willingness to accept (WTA) conservation support significantly differs from actual payment levels. The estimated WTA was found to be 27% lower for the local sheep and goat breeds and 5% higher for the local pig breed, suggesting that differentiated incentive payments would provide a more cost-effective alternative. Additional analysis of breeders' preferences and motives for engaging in local livestock breed production further informs understanding regarding AnGR conservation policy and the importance of accompanying actions to reverse negative population trends. These include reducing administrative barriers and enhancing the market valorisation of local breeds. [ABSTRACT FROM AUTHOR]

Simple Summary: The American mink (Neovison vison) is one of the best-known and most widespread invasive species in China and worldwide. To investigate the genetic characteristics and increase comprehension of the invasiveness process for this species, we compared the genetic characteristics of farmed and feral populations in northeastern China using mitochondrial DNA sequences and microsatellite loci. We found a relatively high diversity among the feral populations that was as high as that of the farmed mink. This demonstrated that high genetic diversity promotes the invasiveness and rapid evolution in the wild. Genetic characteristics play an important role in alien species for achieving high adaptation and rapid evolution in a new environment. The American mink (Neovison vison) is one of the best-known and most widespread invasive species that has successfully invaded the Eurasian mainland over quite a short period, including most parts of northeastern China. However, genetic information on farmed and feral American mink populations introduced in China is completely lacking. In this study, we combined mitochondrial DNA sequences and polymorphic microsatellites to examine the genetic divergence and genetic diversity of farmed and feral American mink populations. Our results suggest that there is admixture of individuals of different genetic characteristics between farmed and feral populations of mink. Furthermore, the genetic diversity of both farmed and feral American mink populations was high, and no bottleneck or population expansion was detected in most of the populations. These findings not only highlight the genetic characteristics of American mink in northeastern China but also contribute to the general understanding of the invasiveness of farmed species. [ABSTRACT FROM AUTHOR]