Polymorphism Analysis Of Candidate Genes On Regulation Of Downy Feather Regeneration And Its Association With Feather Traits In Wanxi White Goose

As a Chinese indigenous breed, Wanxi white goose is famous for its downy traits, andgenetic play important role during this economically important traits formation. BMPfamily, negatively regulate follicle morphogenesis, play pivotal role during featherformation. BMP2, one of BMP family, is a mainly gene on regulation of follicle anddown development. BMPR1A, as BMP receptor, has been ascertained to regulate keratinsynthesis which affect the differentiation and proliferation of feather follicle. ACTB, asthe major component for compose of cytoskeleton, has been showed significantly upregulated during feather regeneration in Wanxi-white goose. In this study, identificationof single nucleotide polymorphisms (SNPs) in BMP2、BMPR1A and ACTB, and thecorrelation between SNPs and downy traits in Wanxi-white goose was performed in thisstudy, which might provide meaningful information in comprehensively understand thegenetic characteristics of downy feather formation and the prospective for breeding ofspecialized downy lines in Wanxi-white goose.There were no polymorphisms detected in BMP2, while an A-T mutation in exon8,1182bp in the mRNA sequence of BMPR1A, was found, which leads to Thr-Ser mutation.The experimental population was defined as CC、DD and CD genotype according to thissite mutation. Another mutation in ACTB was found in exon4,968bp in the mRNAsequence, which leads to Gly-Glu mutation. The experimental population was defined asEE、FF and EF genotype considering to this site mutation. Chi-square test revealed thatall loci were in Hardy-Weinberg balance (P>0.05). The heterozygose、effective numberof alleles and polymorphic information content (PIC) in BMPR1A and ACTB were0.4975and0.4972,1.99and1.9889,0.4356and0.4354, respectively. The results showedthat all loci were in moderate polymorphism and genetic variation.Usually, Wanxi white goose going to molt at about110day of age. Downy and featherwas harvested from every goose and store individually. The weight of downy and featherwere79.39±15.03g per bird and64.68±10.18g per bird respectively. Filling power, fatand oil content, oxygen number, downy length and weight of1000downy were13.68±1.16cm,1.40%±0.98%,32.54±21.59mg/100g,30.50±4.94mm, and2.61±0.49g,respectively. Downy regeneration was determined with3.82±3.07and6.62±1.11persquare centimeters during7thand14thday respectively after moltingGenotypes and downy traits association analysis showed that higher oxygen numberand the number of regenerated downy after7thday of molting were observed in CC genotype than that of DD genotype. While considering downy length, the CD genotypeshowed longer than that of DD and CC genotype. The FF genotype showed betterfilling power than EE genotype. The EF genotype had more number of regenerateddowny than FF and EE genotype after7thday of molting. A heavier weight of1000downy was observed in EF genotype than EE genotype. Taken together, the CCFFgenotype showed better filling power than CDEE, DDEE and CCEF genotypes. TheCDEF genotype showed more number of downs after14thday of molting, heavier weightof1000downs, and longer downy length than CDFF, DDEE and DDFF, CCEFgenotypes, respectively.