Project description:Even though feather pecking (FP) in laying hens has been extensively studied, a good solution to prevent chickens from this behavior under commercial circumstances has not been found. Selection against FP behavior is possible, but for a more effective selection across different populations, it is necessary to characterize the genetic mechanism associated with this behavior. In this study, we use a high FP selection line, which has been selected for 8 generations. We present evidence of the presence of a major dominant allele affecting the FP behavior by using an argument based on the presence of mixture in the distribution of the observed FP and by studying the evolution of the proportion of very high FP along the sequence of 8 generations. This hypothesis is further supported by the fact that the gene transcription profile of the birds performing high FP differs from the profile of the other birds performing FP (456 genes differentially expressed from a total of 14,077 investigated genes). Keywords: severe feather pecking , selection , modeling , inheritance pattern From each selection line (high feather pecking line, low feather pecking line and control line) 60 animals were randomly selected. Within each line the birds were randomly assigned to a cage of 20. The cages were kept in a randomized block design. Number of samples analyzed in total: 179 (60 high feather pecking line, 60 low feather pecking line, 59 control line samples. Common reference design using total-RNA purified from brain from a single F1 cross between the high and low feather pecking line as reference.
Project description:Feather pecking is a major welfare problem in egg production. It may be caused by genetic, physiological and environmental factors. The main aim of this study was to uncover variability in gene expression between individuals from high (HFP) and for low feather pecking (LFP) line using Chicken Gene Expression Microarrays (Agilent Technologies). Samples were assorted to two groups, each containing 9 biological replicates from high feather pecking (HFP) and low feather pecking (LFP) line.
Project description:The feather follicle is a “professional” regenerative organ that undergoes natural cycling and, regeneration after wound plucking. Similar to mammalian hair follicle, dermal papilla (DP) controls feather regeneration, shape, size, and axis. Here we report gene expression profiling for feather DP at different growth stages. For growth phase, we compared gene expression of DP, the ramogenic zone of feather branching epithelium (Erz) and the mesenchymal pulp (Pp). We also compared gene expression of DP at resting phase. To characterize the feather regeneration process, we further profiled gene expression at Day-2 and Day-4 post wound. Our results provide a resource for investigating feather growth and regeneration. Examination of gene expression in dermal papilla (DP) at growth phase and resting phase feather follicle, and during feather regeneration.
Project description:The feather follicle is a “professional” regenerative organ that undergoes natural cycling and, regeneration after wound plucking. Similar to mammalian hair follicle, dermal papilla (DP) controls feather regeneration, shape, size, and axis. Here we report gene expression profiling for feather DP at different growth stages. For growth phase, we compared gene expression of DP, the ramogenic zone of feather branching epithelium (Erz) and the mesenchymal pulp (Pp). We also compared gene expression of DP at resting phase. To characterize the feather regeneration process, we further profiled gene expression at Day-2 and Day-4 post wound. Our results provide a resource for investigating feather growth and regeneration.
Project description:Feather evolution enabled feathered dinosaurs and early Mesozoic birds to venture into new ecological niches. Studying how feathers and scales are specified provides insight into how a new organ evolves. We use genome-wide analyses to identify feather-associated genes and test their feather-forming ability by expressing them in chicken and alligator scales. Intermediate morphotypes revealed five cardinal morphogenetic events: localized growth zone, follicle invagination, branching, feather keratin differentiation and dermal papilla formation. In contrast to molecules known to induce feathers on scales (retinoic acid, beta-catenin), we identify novel scale-feather converters (Sox2, Zic1, Grem1, Spry2, Sox18) which induce only one or several of the five regulatory modules. Some morphotypes resemble filamentous appendages found in feathered dinosaur fossils, while others demonstrate some characteristics of modern feathers. We propose that at least five morpho-regulatory modules were used to diversify ancient reptile scales. The regulatory combination and hierarchical integration led to extant feather forms.
Project description:Even though feather pecking (FP) in laying hens has been extensively studied, a good solution to prevent chickens from this behavior under commercial circumstances has not been found. Selection against FP behavior is possible, but for a more effective selection across different populations, it is necessary to characterize the genetic mechanism associated with this behavior. In this study, we use a high FP selection line, which has been selected for 8 generations. We present evidence of the presence of a major dominant allele affecting the FP behavior by using an argument based on the presence of mixture in the distribution of the observed FP and by studying the evolution of the proportion of very high FP along the sequence of 8 generations. This hypothesis is further supported by the fact that the gene transcription profile of the birds performing high FP differs from the profile of the other birds performing FP (456 genes differentially expressed from a total of 14,077 investigated genes). Keywords: severe feather pecking , selection , modeling , inheritance pattern
Project description:Feather evolution enabled feathered dinosaurs and early Mesozoic birds to venture into new ecological niches. Studying how feathers and scales are specified provides insight into how a new organ evolves. We use genome-wide analyses to identify feather-associated genes and test their feather-forming ability by expressing them in chicken and alligator scales. Intermediate morphotypes revealed five cardinal morphogenetic events: localized growth zone, follicle invagination, branching, feather keratin differentiation and dermal papilla formation. In contrast to molecules known to induce feathers on scales (retinoic acid, beta-catenin), we identify novel scale-feather converters (Sox2, Zic1, Grem1, Spry2, Sox18) which induce only one or several of the five regulatory modules. Some morphotypes resemble filamentous appendages found in feathered dinosaur fossils, while others demonstrate some characteristics of modern feathers. We propose that at least five morpho-regulatory modules were used to diversify ancient reptile scales. The regulatory combination and hierarchical integration led to extant feather forms.
Project description:Feather pecking is a major welfare problem in egg production. It may be caused by genetic, physiological and environmental factors. The main aim of this study was to uncover variability in gene expression between individuals from high (HFP) and for low feather pecking (LFP) line using Chicken Gene Expression Microarrays (Agilent Technologies).
Project description:Feather evolution enabled feathered dinosaurs and early Mesozoic birds to venture into new ecological niches. Studying how feathers and scales are specified provides insight into how a new organ evolves. We use genome-wide analyses to identify feather-associated genes and test their feather-forming ability by expressing them in chicken and alligator scales. Intermediate morphotypes revealed five cardinal morphogenetic events: localized growth zone, follicle invagination, branching, feather keratin differentiation and dermal papilla formation. In contrast to molecules known to induce feathers on scales (retinoic acid, beta-catenin), we identify novel scale-feather converters (Sox2, Zic1, Grem1, Spry2, Sox18) which induce only one or several of the five regulatory modules. Some morphotypes resemble filamentous appendages found in feathered dinosaur fossils, while others demonstrate some characteristics of modern feathers. We propose that at least five morpho-regulatory modules were used to diversify ancient reptile scales. The regulatory combination and hierarchical integration led to extant feather forms.