The influence of beak trimming of two strains of commercial male turkeys (Strains A and B) on behavior during the growing period was investigated. Poults were either left with beaks intact or arc beak trimmed at hatching. Strain by beak treatment interactions were generally lacking, indicating that these two strains responded similarly. Beak trimming did not influence tameness (as measured by r...

Darwin's finches are a classic example of species diversification by natural selection. Their impressive variation in beak morphology is associated with the exploitation of a variety of ecological niches, but its developmental basis is unknown. We performed a comparative analysis of expression patterns of various growth factors in species comprising the genus Geospiza. We found that expression ...

Grooming a bird refers to clipping wing feathers, trimming claws (nails), and on occasion, smoothing and trimming the beak. A veterinarian or experienced technician can perform this service on an otherwise healthy bird. Some disease states can result in nail and beak problems; consequently, all birds should be properly examined at regular intervals every 6 to 12 months.

Weight increases significantly with increased beak size, even after accounting for the correlated variation in overall size (as measured by the two skeletal variables). The beak measurements are very highly correlated with each other, so (1) it is impossible to disentangle their relationships with weight, and (2) they are redundant so that if one is in the model neither of the others explains m...

N 1938 from matings of polydactylous fowl we found newly-hatched I chicks which had an abnormally short upper beak. In some of these chicks the beak gradually became normal, while others developed a crossbeak. The latter type has been referred to in an earlier publication (LANDAUER 1938, Postscript) as probably representing a new hereditary form of cross-beak in fowl. Further studies with this ...

The methylated DNA binding protein-2-H1 (MDBP-2-H1), present in rooster liver, is a member of the histone H1 family which inhibits transcription by binding selectively to methylated promoters. Here we have determined the primary structure of MDBP-2-H1. A comparison between histone H1 and MDBP-2-H1 was achieved by analyzing reversed phase HPLC-purified and V8-digested proteins by mass spectromet...

Lorenzo Alibardi (2010) Cornification of the beak of Rana dalmatina tadpoles suggests the presence of basic keratin-associated proteins. Zoological Studies 49(1): 51-63. An ultrastructural, immunocytochemical, and electrophoretic study on keratinocytes formation in the horny beak of tadpoles of the frog Rana dalmatina was conducted. The study showed that hard cornification in amphibians occurs ...

The hard tissues found in some invertebrate marine organisms represent intriguing paradigms for robust, lightweight materials. The present study focuses on one such tissue: that comprising the beak of the jumbo squid (Dosidicus gigas). Its main constituents are chitin fibers (15-20wt.%) and histidine- and glycine-rich proteins (40-45%). Notably absent are mineral phases, metals and halogens. De...

Compared to male secondary sexual traits, the effect of testosterone (T) on female ornaments is understudied. In particular, it is unclear whether females experience different costs of T elevation than do males and how this affects the relationship between T and ornamentation in the two sexes. I experimentally and correlationally investigated the effect of T on the color of the carotenoid-based...