Study And Application Of Recessive White Feather And Slow Feather Molecular Markers In Guizhou Local Chicken Breeds

The purpose of this study was to identify the white feather gene of Xingyi dwarf chicken white feather line.According to the sequence of TYR gene and PMEL17 gene,a group of primers was designed.The PCR products of Xingyi dwarf chicken was sequenced.The molecular identification methods of dominant white feather and recessive white feather were established to select and identify recessive homozygotes between Roman laying hens and Xingyi dwarf hens.The purpose of this study was to identify the K gene of slow feather line of Guizhou yellow chicken and Yaoshan chicken.According to the sequence of K gene,a pair of primers was designed.The PCR products of Guizhou yellow chicken(GHS)and Yaoshan chicken(YSS)were sequenced.Primers were designed to identify the homozygote of slow feather cocks.A molecular identification method of slow feather K gene will be established.The morphological changes of feathers of different generations of GHS and YSS were counted.The effects of different feather forms on body weight and feather growth were studied.The results are as follows:(1)Through molecular identification,the 196bp insertion fragment of TYR gene of XB was detected.The results of sequencing were consistent with those of the original sequence.No160bp insertion fragment of PMEL17 gene was detected.It was determined that XB was a recessive white feather chicken controlled by TYR gene,and the 160bp insertion fragment of PMEL17 gene of LB was detected by iicc;The results of sequencing were consistent with those of the original sequence.No 196bp insertion fragment of TYR gene was detected.It was determined that LB was a recessive white feather chicken controlled by TYR gene,and the genotype was IICC.The TYR gene of 208 hybrid progenies of XB and LB was detected.It was found that there were 8 genotypes such as IiCC and IICC in the hybrid offspring,but no IICC genotype was detected.9 individuals of iicc type were identified,accounting for 4.3%of all genotypes.By X~2test,the theoretical value was consistent with the actual value(P>0.05).(2)It was amplified by PCR,the insertion fragment of 1305bp was found in the slow feather system of GHS and YSS,and the result of sequence was consistent with that of the original sequence.This PCR fragment can be used as a marker for the detection of slow feather.Based on this clip.The slow feather lines of GHS and YSS were identified by molecular identification.It was found that the accuracy of phenotypic identification of GHS slow feather line was 98.3%,and that of YSs slow feather line was 97.9%.(3)In order to verify the accuracy of molecular identification of slow feather individuals,8 GHS fast feather line cocks and 48 GHS slow feather line hens were selected.The fast and slow feather traits of 146 hybrid progenies were identified.There wFast and slow featherere 67slow feather cocks and 77 fast feather hens.By X~2test,the theoretical value was consistent with the actual value(P>0.05).In order to verify the accuracy of molecular identification of slow feather individuals,6 YSS fast feather line cocks and 36 YSS slow feather line hens were selected.The fast and slow feather traits of 131 hybrid progenies were identified.There were65 slow feather cocks and 66 fast feather hens.By X~2test,the theoretical value was consistent with the actual value(P>0.05).(4)The study found,the feather morphology of different generations of GHS and YSS changed greatly.The original GHS and YSS feathers were mainly isometric-featherand inverted-feather.It accounted for 94.07%and 93.67%of all feather forms.After molecular identification,the feather morphology of slow feather offspring was mainly inverted fast-feathertype and ungrown-feathertype.It accounted for 95.07%and 94.98%of all feather forms.In order to verify the accuracy of molecular identification of slow feather individuals,8 GHS fast feather line cocks and 48 GHS slow feather line hens were selected.The fast and slow feather traits of 146 hybrid progenies were identified.There were 67 slow feather cocks and 77 fast feather hens.By X~2test,the theoretical value was consistent with the actual value(P>0.05).In order to verify the accuracy of molecular identification of slow feather individuals,6 YSS fast feather line cocks and 36 YSS slow feather line hens were selected.The fast and slow feather traits of 131 hybrid progenies were identified.There were 65 slow feather cocks and 66 fast feather hens.By X~2test,the theoretical value was consistent with the actual value(P>0.05).In this paper,the molecular markers for the identification of recessive white feather and slow feather were established,which were proved to be accurate and can be used in production practice.