Gene diversity, agroecological structure and introgression patterns among village chicken populations across North, West and Central Africa

BMC Genetics

Research Article

Xavier Rognon¹  Grégoire Leroy¹  Chia V Yapi-Gnaoré²  N’Goran E Loukou³  Michèle Tixier-Boichard⁴  Bertrand Bed’hom⁴  Khalid Benabdeljelil⁵  Jean-Claude Fotsa⁶  Boniface B Kayang⁷  Richard Osei-Amponsah⁷  Issaka AK Youssao⁸ 

[1] AgroParisTech, UMR1313 Génétique Animale et Biologie Intégrative, 05, F-75231, Paris, France;INRA, UMR1313 Génétique Animale et Biologie Intégrative, 78352, Jouy-en-Josas, France;Centre National de la Recherche Agronomique, 01BP 1740, Abidjan, Côte d’Ivoire;Centre National de la Recherche Agronomique, 01BP 1740, Abidjan, Côte d’Ivoire;Université de Cocody, 22BP 1244, Abidjan, Côte d’Ivoire;INRA, UMR1313 Génétique Animale et Biologie Intégrative, 78352, Jouy-en-Josas, France;Institut Agronomique et Vétérinaire Hassan II, DPBA, Rabat Instituts, BP 6202, 10101, Rabat, Maroc;Station Spécialisée de Recherche Agricole de Mankon (SRRAD), BP 4099, Bamenda, Cameroun;University of Ghana, Legon, Ghana;Université d’Abomey-Calavi, Ecole Polytechnique d’Abomey-Calavi, 01BP 2009, Cotonou, Bénin;

关键词: Allelic Richness;    Genetic Introgression;    Membership Coefficient;    Chicken Population;    Commercial Line;   

DOI  :  10.1186/1471-2156-13-34

 received in 2011-11-04, accepted in 2012-05-07,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundChickens represent an important animal genetic resource for improving farmers’ income in Africa. The present study provides a comparative analysis of the genetic diversity of village chickens across a subset of African countries. Four hundred seventy-two chickens were sampled in 23 administrative provinces across Cameroon, Benin, Ghana, Côte d’Ivoire, and Morocco. Geographical coordinates were recorded to analyze the relationships between geographic distribution and genetic diversity. Molecular characterization was performed with a set of 22 microsatellite markers. Five commercial lines, broilers and layers, were also genotyped to investigate potential gene flow. A genetic diversity analysis was conducted both within and between populations.ResultsHigh heterozygosity levels, ranging from 0.51 to 0.67, were reported for all local populations, corresponding to the values usually found in scavenging populations worldwide. Allelic richness varied from 2.04 for a commercial line to 4.84 for one population from Côte d’Ivoire. Evidence of gene flow between commercial and local populations was observed in Morocco and in Cameroon, which could be related to long-term improvement programs with the distribution of crossbred chicks. The impact of such introgressions seemed rather limited, probably because of poor adaptation of exotic birds to village conditions, and because of the consumers’ preference for local chickens. No such gene flow was observed in Benin, Ghana, and Côte d’Ivoire, where improvement programs are also less developed. The clustering approach revealed an interesting similarity between local populations found in regions sharing high levels of precipitation, from Cameroon to Côte d’Ivoire. Restricting the study to Benin, Ghana, and Côte d’Ivoire, did not result in a typical breed structure but a south-west to north-east gradient was observed. Three genetically differentiated areas (P < 0.01) were identified, matching with Major Farming Systems (namely Tree Crop, Cereal-Root Crop, and Root Crop) described by the FAO.ConclusionsLocal chickens form a highly variable gene pool constituting a valuable resource for human populations. Climatic conditions, farming systems, and cultural practices may influence the genetic diversity of village chickens in Africa. A higher density of markers would be needed to identify more precisely the relative importance of these factors.

【 授权许可】

Unknown   
© Leroy et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.