Project description:Beak deformities (BD) of different forms have been documented in many wild birds. The phenomenon is termed as “the largest epizootic of gross abnormalities ever recorded among wild bird populations.” Frequencies of 1% to 3% of BD (crossed beaks) were found in several indigenous chickens including Silkies, Qingyuan Partridge, Huxu, and the Beijing-You (BJY) chickens (studied here). Birds with deformed beaks have poor production performance and induce higher mortality. Therefore, BD represents an economic as well as a welfare problem. Our lab have focused and performed studies on this complex trait/disease for 7 years. Therefore, we performed a single SNP, a pathways-based genome-wide association study (GWAS), and a genome-wide CNV detection with the genotype data of 48 BD (case) and 48 normal (control) birds from Affymetrix 600K HD genotyping arrays, using ROADTRIPS, SNP ratio test (SRT) and PennCNV, respectively. To the best of our knowledge, this is the first GWAS and CNV study to investigate the mutations and genomic structural variations in the deformed and normal beaks of chickens. The findings herein are worth of further functional characterization for better understanding the genetic mechanisms of BD in chickens and wild birds as well.
Project description:Relative expression levels of mRNAs in chicken cecal epithelia experimentally infected with Eimeria tenella were measured at 4.5 days post-infection. Two weeks old chickens were uninfected (negative control) or were orally inoculated with sporulated oocysts of Eimeria tenella. Cecal epithelia samples were collected from >12 birds in infected or uninfected group at 4.5 d following infections, in which samples from 4 birds were pooled together to form a total 3 biological replicates in each group. Parasite merozoites were also collected from four infected chickens at 5 d after infections. Uninfected control samples, merozoites and infection group samples were selected for RNA extraction and hybridization on Affymetrix microarrays. We used Affymetrix GeneChip chicken genome arrays to detail the chicken cecal epithelia gene expression in the control and E. tenella-infected birds.