GENETIC BACKGROUND AND HSP70 GENE POLYMORPHISMS FOR HEAT TOLERANCE IN INDIGENOUS CHICKENS OF KENYA

Abstract

It is postulated that  chickens were first domesticated in Asia  around 8000  years  ago and spread to the rest of the world.  This study  investigated  the origins,  phenotypes  as  well  as polymorphisms  at  a  candidate gene implicated  for  heat -tolerance  in  indigenous  chickens  from  four  agro  climatic  zones  of  Kenya  (Lamu archipelago,  the  Turkana  basin,  Victoria  basin  and  the  Mount  Elgon  Catchment).  Phenotypic  traits  for  heat tolerance were collected using the ODK collect suite and recorded. DNA was  extracted  from 296 indigenous
chickens.  Mitochondrial  DNA  d-loop  region  and  the  heat  shock  protein  7 0 ( H S P 7 0 )  gene  were  amplified using an optimized PCR protocol. Analysis of the HSP70 revealed the presence of three heterozygous and three homozygous sequences. The ancestral red jungle fowl was used as the reference sequence.
DnaSP  generated  28  mtDNA  haplotypes.  Our  samples  clustered  into  four  of  the  five  reference  haplogroups downloaded  from  GenBank.  Most  of  our  samples  clustered  into  Haplogroup  E.  Haplogroup  E.  This  study characterized  the  phenotypes  of  indigenous  chickens,  characterized  the  origins  and  HSP70  gene  functional polymorphisms in the various climatic regions of Kenya

Key words: arid and semi-arid lands, climate change, drought, heat stress, poultry