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...

Variation in avian coloration is produced by coordinated pigmentation of thousands of growing feathers that vary in shape and size. Although the functional consequences of avian coloration are frequently studied, little is known about its developmental basis, and, specifically, the rules that link feather growth to pigment uptake and synthesis. Here, we combine biochemical, modeling, and morpho...

The identification of bird species from feather fragments is useful in many disciplines, including forensic science. Feather evidence can be helpful to criminal investigations in demonstrating physical contact between clothing manufactured with down feathers, or it may provide specific links to the crime scene by identifying the species or group of birds from which the feather evidence came. Th...

Fault bars are common stress-induced feather abnormalities that could produce feather damage thus reducing flight performance. For that reason, it has been hypothesized that birds may have evolved adaptive strategies that reduce the costs of fault bars (the ‘fault bar allocation hypothesis’). An untested prediction of this hypothesis is that fault bars in important feathers for flight (wing and...

Ionizing radiation (IR) is a common therapeutic agent in cancer therapy. It damages normal tissue and causes side effects including dermatitis and mucositis. Here we use the feather follicle as a model to investigate the mechanism of IR-induced tissue damage, because any perturbation of feather growth will be clearly recorded in its regular yet complex morphology. We find that IR induces defect...

Severe feather pecking (SFP) in chickens is a detrimental behaviour with possibly neurochemical deficits at its base. Recent neurological studies depicted conflicting results on the role of serotonin (5-hydroxytryptamine, 5-HT) and dopamine (DA) in the development and display of feather pecking. We studied brain monoamine levels and behaviour in domestic chickens divergently genetically selecte...

The developmental basis of morphological complexity remains a central question in developmental and evolutionary biology. Feathers provide a unique system to analyze the development of complex morphological novelties. Here, we describe the interactions between Sonic hedgehog (Shh) and bone morphogenetic protein 2 (Bmp2) signaling during feather barb ridge morphogenesis. We demonstrate that acti...