The NRC (1996) changed from the factorial protein system to a metabolizable protein (MP) system for beef cattle. In the MP system, dietary crude protein (CP) is subdivided into degraded intake protein (DIP) and undegraded intake protein (UIP). The quantity of microbial protein produced in the rumen dictates DIP requirements. Steam-flaked corn is the predominant grain used in the diets of finish...

Olfaction may play an important role in regulating bird behavior, and has been suggested to be involved in feather-pecking. We investigated possible differences in the body odors of red junglefowl females by using an automated olfactometer which assessed the ability of trained mice to discriminate between the odors of uropygial gland secretions (the main carrier of potential individual odors in...

The preservation of delicate structures such as feathers is very rare in the paleontological record, due to the fragility of their components. Fossil feathers have been reported from approximately 50 deposits around the world, from the Late Jurassic to the Pleistocene. In Brazil initial findings consisted of a primary feather of a large bird found in the Tremembé Formation. Other occurrences ar...

Variance components and selection response for feather pecking behavior were studied by analyzing the data from a divergent selection experiment. An investigation indicated that a Box-Cox transformation with power lambda = -0.2 made the data approximately normally distributed and gave the best fit for the model. Variance components and selection response were estimated using Bayesian analysis w...

The newly described technique of extracting corticosterone (CORT) from bird feathers may serve as a less invasive, more integrated measure of a bird’s stress response. Previous work indicated that elevated plasma CORT resulted in poorer quality feathers during molt. We tested the hypothesis that a direct link exists between plasma and feather CORT concentrations. We experimentally increased pla...

The origin of feathers is an important question in Evo-Devo studies, with the eventual evolution of vaned feathers which are aerodynamic, allowing feathered dinosaurs and early birds to fly and venture into new ecological niches. Studying how feathers and scales are developmentally specified provides insight into how a new organ may evolve. We identified feather-associated genes using genomic a...

Pathologic feather picking in companion avian species has been attributed to multiple underlying disorders, and many of these birds are thought to be pruritic. Allergies have been discussed as possible contributors to this common and devastating dermatologic disease. This article reviews published information and research currently being conducted on hypersensitivity disorders in avian species....

The River Elbe is responsible for influxes of contaminants into the Wadden Sea World Heritage Site. We investigated levels of polychlorinated biphenyls (PCBs), oxychlordane (OxC), hexachlorobenzene (HCB), hexachlorocyclohexanes (α-, β-, γ-HCHs), dichlorodiphenyltrichloroethane (DDT) and its metabolites, and polybrominated diphenyl ethers (PBDEs) in blood and feathers from Eurasian oystercatcher...

Severe feather pecking (SFP) in laying hens is a detrimental behavior causing loss of feathers, skin damage and cannibalism. Previously, we have associated changes in frontal brain serotonin (5-HT) turnover and dopamine (DA) turnover with alterations in feather pecking behavior in young pullets (28-60 days). Here, brain monoamine levels were measured in adult laying hens; focusing on four brain...

Keratinases are a group of proteolytic enzymes that display the capability of degrading insoluble keratin substrates such as feather resulting as poultry waste. Entrapment of crude/purified enzyme within a matrix is a common method for immobilization. An immobilized enzyme provides increased resistance to changes in conditions such as pH or temperature. It also allows enzymes to be held in plac...