FUNCTIONAL POLYMORPHISMS AT A CANDIDATE GENE FOR MEAT AND EGG PRODUCTION IN INDIGENOUS CHICKENS OF KENY A

Abstract

Indigenous  chickens  provide  large  proportion  of  quality  protein  in  human  diet  in  terms  o f  meat  and  eggs. Indigenous chicken are reared under the free range system. Commercial chickens produce much more meat and  eggs;  but  the  meat  and  egg  quality  has  been  affected  in  terms  of  taste,  flavor  and  micronutrients. Indigenous  chickens  are  largely  unexploited  and  have  ecotypes  capable  of  producing  more  meat  and  eggs. Cross-breeding  of  indigenous  chickens  with  exotic  chickens  to  increase  meat  and  egg  production  has  led  to genetic erosion thus loss of important production traits. This research characterized functional polymorphisms of two candidate genes associated with meat and egg production in the indigenous chicken. DNA was extracted from  96  unrelated  chickens  sampled  from  three  populations  not  involved  in  the  initial  cross -breeding improvement  program:  TransNzoia,  West  Pokot,  Turkana,  Marsabit  and  Lamu  counties.  The  presence  of Prolactin  gene  and  Insulin  growth  like  factor  1  gene  were  amplified  using  an  optimized  PCR  protocol.
Electrophoresis was then carried out on the PCR products on a 2% Agarose gel and the bands viewed under a UV light. The band size for prolactin gene was found to be 130bp and 154 bp while for IGF-1 gene was found to
be 813 bp .These two genes were sequenced and polymorphisms identified. Prolactin gene was found to have a 24bp INDEL while IGF-1 was found to have point  mutations and INDEL’s. This is the first study in Kenya to sequence  production  traits  genes  of  indigenous  chickens.  Analysis  of  the  production  traits  will  be  used  for molecular breeding work and be adopted by the national poultry breeding programs to increase quality meat and egg production in indigenous chicken.