Non-iridescent structural plumage color is typically produced by coherent scattering of light within a matrix of keratin and air (a ;spongy layer') in feather barbs. It remains unclear what role, if any, the basal melanin layer underlying this spongy layer plays in the production of coloration. Amelanism in birds with structural color is a ;natural experiment' in which melanin pigmentation is l...

Organogenesis involves a series of dynamic morphogenesis and remodeling processes. Since feathers exhibit complex forms, we have been using the feather as a model to analyze how molecular pathways and cellular events are used. While several major molecular pathways have been studied, the roles of matrix degrading proteases and inhibitors in feather morphogenesis are unknown. Here we addressed t...

Expression of Lunatic fringe mRNA was studied during feather morphogenesis and showed three stages of dynamic expression pattern. (1) Lunatic fringe was first expressed in the epithelium as a ring bordering the feather primordium when it was initially induced. (2) Shortly after, it showed a polarized pattern, first toward the lateral side of the feather primordium and then made a 90 degrees C s...

1. Feather pecking is one of the major problems facing the egg industry in non-cage systems and is set to become even more of an issue with the European Union ban on the keeping of laying hens in barren battery cages which comes into force in 2012 and the prospect of a ban on beak-trimming. Reducing feather pecking without resorting to beak treatment is an important goal for the poultry industr...

A feather-degrading culture was enriched with isolates from a poultry waste digestor and adapted to grow with feathers as its primary source of carbon, sulfur, and energy. Subsequently, a feather-hydrolytic, endospore-forming, motile, rod-shaped bacterium was isolated from the feather-degrading culture. The organism was Gram stain variable and catalase positive and demonstrated facultative grow...

Three Bacillus species (B. subtilis LFB-FIOCRUZ 1270, B. subtilis LFB-FIOCRUZ 1273, and B. licheniformis LFB-FIOCRUZ 1274), isolated from the poultry industry, were evaluated for keratinase production using feathers or feather meal as the sole carbon and nitrogen sources in a submerged fermentation. The three Bacillus spp. produced extracellular keratinases and peptidases after 7 days. Feather ...

results the pcr approved the bacillus genus of the isolates. the strain of bacillus subtilis was identified using biochemical tests. 40 ºc and ph 11 are the optimum condition for maximum keratinase enzyme activity. objectives the aim of this study was the isolation of feather degrading bacillus spp.from a poultry waste and the optimization of conditions for the highest enzyme activity and feath...

1. The formation of the feather pattern has been studied in skin explants obtained from the lumbar region of the spinal pteryla of 6\to 7^-day chick embryos. Explants were cultured in vivo on the chorioallantoic membrane (CAM) or in vitro, either on semi-solid natural media (containing whole chick embryo extract (J£) or chick brain extract (EC)), or in a liquid synthetic medium (199). 2. Feathe...

A tremendous diversity of avian color displays has stimulated numerous studies of natural and sexual selection. Yet, the developmental mechanisms that produce such diversification, and thus the proximate targets of selection pressures, are rarely addressed and poorly understood. In particular, because feathers are colored during growth, the dynamics of feather growth play a deterministic role i...

Cooling is one of most common thermal processes used to improve the quality and safety of food products and to extend their shelf life (WANG; SUN, 2003). In industrial processing of poultry, immediately after slaughter, bleeding, hot water immersion, feather withdraw and viscera withdraw, poultry carcasses have to be chilled to reduce their temperature from approximately 40 to 4 °C, which contr...