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From the beginning of domestication, the transportation of domestic animals resulted in genetic and demographic processes that explain their present distribution and genetic structure. Thus studying the present genetic diversity helps to better understand the history of domestic species. Methodology/Principal Findings. The genetic diversity of domestic goats has been characterized with 2430 individuals from all over the old world, including 946 new individuals from regions poorly studied until now (mainly the Fertile Crescent). These individuals represented 1540 haplotypes for the HV segment of the mitochondrial DNA (mtDNA) control region. This large-scale study allowed the establishment of a clear nomenclature of the goat maternal haplogroups. Only five of the six previously defined groups of haplotypes were divergent enough to be considered as different haplogroups. Moreover a new mitochondrial group has been localized around the Fertile Crescent. All groups showed very high haplotype diversity. Most of this diversity was distributed among groups and within geographic regions. The weak geographic structure may result from the worldwide distribution of the dominant A haplogroup (more than 90% of the individuals). The large-scale distribution of other haplogroups (except one), may be related to human migration. The recent fragmentation of local goat populations into discrete breeds is not detectable with mitochondrial markers. The estimation of demographic parameters from mismatch analyses showed that all groups had a recent demographic expansion corresponding roughly to the period when domestication took place. But even with a large data set it remains difficult to give relative dates of expansion for different haplogroups because of large confidence intervals Conclusions/Significance. We propose standard criteria for the definition of the different haplogroups based on the result of mismatch analysis and on the use of sequences of reference. Such a method could be also applied for clarifying the nomenclature of mitochondrial haplogroups in other domestic species.

The effective design and implementation of interventions that reduce vulnerability and poverty require a solid understanding of underlying poverty dynamics and associated behavioral responses. Stochastic and dynamic benefit streams can make it difficult for the poor to learn the value of such interventions to them. We explore how dynamic field experiments can help (i) intended beneficiaries to learn and understand these complicated benefit streams, and (ii) researchers to better understand how the poor respond to risk when faced with nonlinear welfare dynamics. We discuss and analyze dynamic risk valuation experiments in Morocco, Peru, and Kenya.

Les techniques d'élevage intensif appliquées dans les systèmes agricoles ont une influence négative sur la biodiversité des animaux domestiques. Une des mesures mises en oeuvre afin de juguler ce phénomène d'érosion génétique est la conservation des ressources génétiques des animaux d'élevage (RGAs). La problématique de conservation est d'arbitrer entre des impératifs de préservation et le caractère fini des ressources financières. Cette problématique a été abordée en retenant l'approche développée par Weitzman comme cadre d'analyse et des races ovines et caprines retenues dans le cadre d'un projet de recherche européen (Econogene) comme objet de recherche. Choisir les races à préserver revient à élaborer et à pondérer des critères de conservation. Dans le cadre de cette thèse, cette question a été approchée sous trois angles prospectifs distincts : politique, génétique et économique. Le quatrième angle, qualifié de méthodologique, a consisté en l'élaboration de modèles d'optimisation comme outils d'aide à la décision. Le premier angle s'est focalisé sur les déterminants des décisions des choix de conservation observés au niveau de l'Union européenne. Les résultats ont montré que les programmes de conservation opèrent indépendamment des risques d'extinction. Le second angle se place au niveau génétique. Les résultats ont révélé que les races originales présentent de faibles taux d'hétérozygotie et vice versa. Le troisième angle s'est attaché à analyser les critères de conservation et leur pondération par le biais d'une analyse économique intégrant les points de vue d'un échantillon d'experts. Les résultats ont permis de montrer que la dissemblance génétique est perçue comme l'attribut le plus important. Enfin, le dernier angle, qualifié de méthodologique, a consisté en l'élaboration de modèles bioéconomiques comme outils d'aide à la décision. A travers les résultats de ce travail, certaines implications empiriques et méthodologiques ont pu être identifiées. Celles-ci constituent une ébauche d'une vision pour la conservation des RGAs qui devrait s'articuler en quatre volets : un volet protection, un volet conservation, un volet valorisation et un volet recherche. (AGRO 3)--UCL, 2006

We consider the choice of farm animal breeds for conservation programmes. Based on an analysis of past decisions in EU member countries to enter breeds into the conservation programmes of rural development plans and based on the results of an expert survey among breed societies and scientists, we find an inconsistency in the valuation of breed characteristics. Policy makers seem to be less concerned about considering true extinction risk and diversity and more about cultural values and about means to benefit a larger number of farmers for raising rare breeds.

Rapidly declining biodiversity has made international and national policies focus on the question of how best to protect genetic resources. Loss of biodiversity does not only concern wildlife, but equally affects agriculturally used species. These species, of foremost importance for the subsistence of humankind, are subject to pressures sometimes similar and sometimes very distinct from those of their wild counterparts. And so are the losses implied by this decline in diversity. This handbook was conceived within the project Sustainable conservation of animal genetic resources in marginal rural areas: Integrating molecular genetics, socio-economics and geostatistical approaches (ECONOGENE - EC-QLK5-CT-2001-02461) to review and design methods that can serve as a basis to guide conservation policies for livestock breeds at risk of extinction. It is part of the broader effort of a multidisciplinary research team assessing the diversity of European sheep and goat breeds. The final goal of the project is to assess the impact of current and future policies on these breeds.