Genetic analysis of local Vietnamese chickens provides evidence of gene flow from wild to domestic populations

<p>Abstract</p> <p>Background</p> <p>Previous studies suggested that multiple domestication events in South and South-East Asia (Yunnan and surrounding areas) and India have led to the genesis of modern domestic chickens. Ha Giang province is a northern Vietnamese region, where local chickens, such as the H'mong breed, and wild junglefowl coexist. The assumption was made that hybridisation between wild junglefowl and Ha Giang chickens may have occurred and led to the high genetic diversity previously observed. The objectives of this study were i) to clarify the genetic structure of the chicken population within the Ha Giang province and ii) to give evidence of admixture with <it>G. gallus</it>. A large survey of the molecular polymorphism for 18 microsatellite markers was conducted on 1082 chickens from 30 communes of the Ha Giang province (HG chickens). This dataset was combined with a previous dataset of Asian breeds, commercial lines and samples of Red junglefowl from Thailand and Vietnam (Ha Noï). Measurements of genetic diversity were estimated both within-population and between populations, and a step-by-step Bayesian approach was performed on the global data set.</p> <p>Results</p> <p>The highest value for expected heterozygosity (> 0.60) was found in HG chickens and in the wild junglefowl populations from Thailand. HG chickens exhibited the highest allelic richness (mean A = 2.9). No significant genetic subdivisions of the chicken population within the Ha Giang province were found. As compared to other breeds, HG chickens clustered with wild populations. Furthermore, the neighbornet tree and the Bayesian clustering analysis showed that chickens from 4 communes were closely related to the wild ones and showed an admixture pattern.</p> <p>Conclusion</p> <p>In the absence of any population structuring within the province, the H'mong chicken, identified from its black phenotype, shared a common gene pool with other chickens from the Ha Giang population. The large number of alleles shared exclusively between Ha Giang chickens and junglefowl, as well as the results of a Bayesian clustering analysis, suggest that gene flow has been taking place from junglefowl to Ha Giang chickens.</p

Reproductive prefomance of goats in traditional livestock systems in communal areas in Zimbabwe

Individual and herd performances of goats were monitored in nine communal areas in Zimbabwe, which are representative of the various traditionally managed production systems. Between 1 September 1990 and 1 November 1991, 6950 goats from 254 farms were monitored twice monthly on an individual basis. Results showed that the reproductive performance varied markedly with the natural and socio-economic environment of the animals. Animals in recently established communal areas performed better than those from both the old communal areas and the heavily degraded natural environments. The animals' potential was achieved through the individual techniques of their owners

Etude de faisabilité d'un projet d'élevage au Mozambique : districts de Magude, Angonia et Tsangano

Dans les districts de Magude, Angonia et Tsangano (Mozambique), l'élevage bovin en secteur paysan a été gravement affecté par la guerre civile. Entre 1983 et 1995, les effectifs ont baissé de 95 % à Magude et de 70 % à Angonia et Tsangano. Une enquête auprès de 300 agriculteurs a permis de comprendre l'histoire et le fonctionnement du système agro-élevage dans ces trois districts. L'élevage bovin est destiné principalement à la traction animale (labour à Magude, transport à Angonia et Tsangano). Pratiqué par des agro-éleveurs et non par des pasteurs, il est un important moyen d'accumulation de l'épargne. La réhabilitation de cet élevage passe par la reconstruction des systèmes sociaux de gestion de l'espace (pâtures, labours). Elle nécessite, à Magude, l'introduction de cheptel importé. Les stations zootechniques de Chobela (race N'Guni) et Angonia (race Angonia) peuvent servir de support à une action de formation et de recherche pour le développement de l'élevage bovin

Projet CIRAD-Zimbabwe : rapport d'activités 1997

Ce rapport dresse le bilan des activités du CIRAD-EMVT au Zimbabwe, effectuées à la demande du MAE, dans le cadre de quatre projets actuellement en cours d'exécution et d'un appui pour la préparation de la Conférence du CITES, tenue en Juillet 1997 à Harare. 1-"Conservation de la biodiversité dans la Vallée du Zambèze après l'éradication de la mouche tsé tsé" : ce programme est devenu opérationnel en 1997 avec la mise en oeuvre d'une première phase, destinée à dresser un bilan-diagnostic de la biodiversité dans la zone et à identifier un certain nombre de microprojets de développement axés sur la valorisation des ressources locales. 2-"Projet Ecologie Comparée" : actuellement concentré sur la dynamique et les interrelations tiques-bétail domestique et animaux sauvages sur le site du Ranch de Kelvin Grove (ARDA). 3-"Projet régional de lutte contre la tsé tsé (RTTCP)". Entré dans sa phase en 1997, ce projet devrait être suivi en 1998 d'une phase transitoire de redéfinition des objectifs, en terme de lutte contre la tsé tsé, et en 1999, voir ses prérogatives étendues à d'autres maladies animales. 4-"Projet Faune-Villages" : ce programme a permis en 1997 d'encadrer un plan d'abattage raisonné de 500 animaux, en assurant notamment une formation des agents de terrain. Ce programme, qui a été unanimement reconnu et apprécié, tant par les populations locales que par les partenaires institutionnels (District Council) devrait être suivi en 1998 d'une nouvelle campagne, portant cette fois sur un programme de formation et sur l'accompagnement scientifique et technique d'un plan d'abattage de 1500 animau

Prevalência da infecção pelo vírus da artrite encefalite caprina no estado do Ceará, Brasil Prevalence of caprine arthritis encephalitis virus infection in the State of Ceará, Brazil

A elevação do risco de contaminação pelo vírus da artriteencefalite caprina (CAEV) em rebanhos caprinos nativos e sem raça definida (SRD) tem sido verificada paralelamente à introdução de caprinos de raças exóticas no Brasil, o que motivou a realização deste levantamento epidemiológico no Estado do Ceará. Para o diagnóstico da infecção pelo CAEV, utilizou-se a microtécnica de imunodifusão em gel de ágar. Foram pesquisadas 4019 amostras de soro caprino em 30 municípios do Ceará. A prevalência da infecção pelo CAEV verificada foi de 1% (40/4019 animais), sendo a maior prevalência (11,1%) na região metropolitana de Fortaleza. Analisando a distribuição de animais soropositivos nos municípios pesquisados, constatou-se que um terço dos municípios (10/30) apresentaram pelo menos um animal soropositivo. Verificou-se maior prevalência (p<5%) nos caprinos mais velhos quando comparados com os jovens. A análise por sexo e composição do rebanho mostrou que os machos estavam estatisticamente mais afetados (p<5%). Considerando-se o grau de sangue, 5,02% de raças puras e 0,12% de animais mestiços apresentavam anticorpos contra CAEV. Dentre os soropositivos, a raça Parda Alpina foi estatisticamente mais afetada (p<5%). Com base nos resultados, pode-se verificar que o lentivírus de pequenos ruminantes já se encontra disseminado nas várias regiões do Ceará e que, provavelmente, os reprodutores sejam a principal fonte de transmissão viral entre os rebanhos nativos/SRD.<br>This epidemiological study in the State of Ceará, Brazil was motivated by the risk of infection with caprine arthritis encephalitis virus (CAEV) through introduction of exotic caprines. For diagnosis of CAEV infection the agar gel imunodifusion microtechnic was used. 4019 goat serum samples were collected in 30 counties. The prevalence of CAEV infection was 1% (40/4019 animals). The highest prevalence (11.1%) was found in the metropolitan area of Fortaleza, the area with highest goat milk production. The analysis of the distribution of seropositive animals in the studied counties showed that 33% (10/30) had at least one positive animal. The highest prevalence was found (p <0.05) in older animals. The males were more affected (p<0.05). The pure breeds presented 5.02% of animals with antibodies against the CAEV and the half-breeds 0,12%. The Alpine breed was the more affected (p<0.05) among all breeds studied. It was verified that the small ruminant lentivirus is already disseminated in several areas of the Stete of Ceará and that the males are probably the main source of transmission to the native/SRD flocks