title: Microsatellite based genetic diversity study in indigenous chicken ecotypes of Karnataka.
abstract: OBJECTIVE
  The current study was the first of its kind taken upon indigenous ecotypes of the Karnataka in order to unravel the diversity details at 20 chicken microsatellite regions.
  
  
  METHODS
  210 indigenous chicken belonging to six districts of Bangalore and Mysore division formed the target sample for the present study. The genomic deoxyribonucleic acid was isolated by phenol chloroform isoamyl alcohol method. A panel of 20 microsatellite regions, including 14 recommended by FAO and six identified from published scientific literature became the targeted chicken genomic region. 27-33 samples were successfully genotyped in each of the six ecotypes through simplex or multiplex polymerase chain reactions, polyacrylamide gel electrophoresis and silver staining for the selected microsatellite panel.
  
  
  RESULTS
  The chickens of Ramanagara and Chamrajnagara were most distant with a Nei's genetic distance value of 0.22. The chickens of Bangalore rural and Mysore were least distant with a value of 0.056. The Ramanagara and Chamrajnagara pair had Nei's genetic identity value of 0.802, which is least among all pairs of ecotypes. There were five main nodes from which the six ecotypes evolved on the basis 20 microsatellite markers used in this study. This study indicates that the four ecotypes Ramnagara, Bangalore Rural, Chickaballapura and Mysore are genetically identical due to their common ancestral evolution while, Mandya and Chamrajnagara ecotypes formed a relatively different cluster due to a separate common ancestral chicken population and less number of generations since drifting from bifurcation node.
  
  
  CONCLUSIONS
  Twenty microsatellite markers based genetic diversity study on six indigenous ecotypes indicated lower genetic distances as well as lower FST values compared to the distinguished breeds reported. There were two main clusters, which differentiated into six ecotypes. They may differentiate into more distinct varieties if bred in isolation for a longer number of generations.
authors.affiliation: Department of Animal Genetics and Breeding, Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Shimoga, Karnataka, India.
authors.forename: B H
authors.initials: BH
authors.lastname: Rudresh
authors.affiliation: Department of Livestock Production and Management, Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Bangalore, Karnataka, India.
authors.forename: H N N
authors.initials: HN
authors.lastname: Murthy
authors.affiliation: Department of Animal Genetics and Breeding, Veterinary College, Karnataka Veterinary, Animal and Fisheries sciences University, Bangalore, Karnataka, India.
authors.forename: M R
authors.initials: MR
authors.lastname: Jayashankar
authors.affiliation: All India Coordinated Research Project on Poultry Meat, Karnataka Veterinary, Animal and Fisheries Sciences University, Veterinary College, Bangalore, Karnataka, India.
authors.forename: C S
authors.initials: CS
authors.lastname: Nagaraj
authors.affiliation: Department of Veterinary Physiology and Biochemistry, Veterinary College, Karnataka Veterinary, Animal and Fisheries sciences University, Shimoga, Karnataka, India.
authors.forename: A M
authors.initials: AM
authors.lastname: Kotresh
authors.affiliation: Institute of Animal Health & Veterinary Biologicals, Bangalore, Karnataka Veterinary, Animal and Fisheries Sciences University, Karnataka, India.
authors.forename: S M
authors.initials: SM
authors.lastname: Byregowda
keywords: animal genetic resources; ecotypes; microsatellites; polyacrylamide gel