Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 25 for “"beak"”.
-
Beak design in folding-shearing
[Restricted]
-
Beak and feather disease virus candidate vaccine development
[Fix supervisors field.] Psittacine beak and feather disease, caused by a circovirus known as beak and feather disease virus (BFDV), is a threat to both wild and captive psittacine species. There is currently no vaccine against BFDV and safe and affordable vaccine candidates are needed to alleviate …
-
Molecular studies on beak and feather disease virus
Includes bibliographical references.
-
Development of a potential challenge model and plant-produced vaccine candidate for beak and feather disease virus
Psittacine beak and feather disease (PBFD), the most prevalent viral disease affecting psittacines, is caused by beak and feather disease virus (BFDV). An outbreak of the disease has been reported in wild endangered Cape parrots (Poicephalus robustus), which is endemic to South Africa. No treatment …
-
The Effects of Beak Trimming and Claw Reduction on Growing and Early Laying Parameters, Fearfulness, and Heterophil to Lymphocyte Ratios
… tissue of the claw with microwave energy and the beak tissue with infrared energy. This effectively claw and beak trims the birds. To test this technique on chickens, one-half of two strains of 1,200 Leghorn chicks were each subjected to the claw reduction (RC) technique at hatch, while one-half …
-
Effect of juvenile dietary regime and time of beak trimming on pullet growth, subsequent egg production and incidence of prolapse in Leghorns
Beak trimming at two different ages, Week-1 and Week-8, under four dietary regimens, varying in percent crude protein (CP) and metabolizable energy (ME) were compared. The dietary regimens were conventional high energy (CHE), conventional medium energy (CME), conventional low energy (CLE) and …
-
Surviving Alpha: Using sequential analysis to examine the behaviours of Black-legged Kittiwake chicks during sibling pecking attacks
… attacks were examined by Cullen (1957) whereby beak hiding motions by beta chicks such as facing away or tucking in the beak served as appeasement strategies and these were discussed as adaptations to Kittiwakes’ habit of cliff nesting. Use of appeasement by beta chicks suggests that, …
-
Caractérisation phénotypique et gestion de la population de poulets locaux dans les communes de Dassa et de Toffo au Bénin
… are pink (45.40 %) and white (36.80 %). The beak colour goes from white (0.3 %) through yellow (9.61 %) and black (27.45 %) to brown (40.27 %). The skin is essentially pink, light pink but legs are white and grey. Eyes are most orange (70.14 %) and brownish (27.75 %). The two sexes were not …
-
Mechanosensory structures in the beaks of probe-foraging birds in relation to their foraging ecology
… using a specialised bill-tip organ in their beaks. This enables them to remotely detect the location of prey submerged in opaque substrates in the absence of all other sensory cues. The bill-tip organ that facilitates remote-touch is made up of mechanoreceptors housed in dense clusters of …
-
Identification of the Molecular Basis of Morphological Variation in Avian Beaks
… changes in neural crest cells of the developing beaks for the chicken, duck, and quail, both before and after morphological variation is evident. I found that neural crest cells have established a species-specific gene expression profile that predates morphological variation. In addition to …
-
Multi-object and multi-feature models of thumb anatomy for population based morphological assessment
… surfaces of the bones; the angle of volar beak protrusion; the angle of trapezial inclination; the surface areas of the articular facets; and the radii of curvature. In line with the respective hypotheses, the distance between the articular surfaces and the angle of volar beak protrusion …
-
Morphological and Hematological Responses to Hypoxia During Development in the Japanese quail, Coturnix coturnix
… of hypoxic damage by hatch. Heart and body mass, beak and toe length, hemoglobin, and hematocrit were measured to determine embryo responses to hypoxia during development at days 10, 15, and hatch. Hypoxia seemed to have the most deleterious effects on eggs in continuous hypoxia. Collectively, …
-
The Rise of Modern Avian Flight: Wing Movement and Joint Mobility Within Ornithurae
… characteristics (e.g., feathers, a toothless beak, small body size) among non-avian theropod dinosaurs and Mesozoic bird-like taxa are now well understood. Yet, despite more than a century of research, the origin and evolution of avian flight itself remain poorly understood and the precise …
-
Studio sui calamari Loligo vulgaris (Lamarck, 1798) e Loligo forbesii (Steenstrup, 1856) delle acque della Sardegna
… were also performed morphometric analysis of the beaks and calculated specific correlations with the animal size. Considering the taxonomic value of the beak such information may be helpful in studies on diets of predators of these species.
-
Isolation and Characterization of Chitinases From Dasypus Novemcinctus, the Nine-Banded Armadillo
The ability of armadillos to beak down chitin was investigated. Both indigenous and endogenous chitinases were studied. Armadillos were collected and samples of their gastric and pancreatic tissues were removed. Tissues were lyophilized and stored at -20° C until they could be resuspended in the …
-
Exploring the Soft Tissue of the Archosaurian Feeding System through Evolutionary and Developmental Temporal Space
… or edentulous jaws covered in a rhamphotheca (=beak) in oviraptors. In the fossil record, morphological modifications can be seen in fossilized skeletal remains, but this is an incomplete picture of a living organism. The skeletal system of an organism is the housing and support, and it is …
-
Anting Behavior in Birds: Ant Selection and Effect of ant Chemistry on Feather Ectoparasites
… are then rubbed with ants held in the bird's beak. The potential associations among ants, feather ectoparasites and birds make anting behavior an important community-level interaction. Although this behavior is cosmopolitan in distribution and occurs in a wide variety of passerine birds, it …
-
Knemidokoptic mite infections on the Cape Peninsula population of Black Sparrowhawks
… can range from featherloss and skin lesions to beak deformities. Although known to infect multiple species of Passeriform birds, very few cases have ever been reported in birds of prey. An unusually high number of Black Sparrowhawks of the Cape Peninsula were identified as being affected by …
-
Implications of climate change on the reproductive success of the Southern Yellow-billed Hornbill, Tockus leucomelas
… imaging experiment revealed that the large beak of hornbills (both males and females) plays an important role in non-evaporative heat loss. Hornbills were observed to dissipate up to 19.9 % of the total non-evaporative body heat loss via the beak. This water-saving mechanism can be highly …
-
Evolutionary palaeoecology of the megaherbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta, Canada
… of food. These include feeding height, skull and beak morphology, jaw mechanics, and tooth morphology and wear. Evidence is sought for taxonomic separation in ecomorphospace, particularly between coexisting species, which is known to reflect niche relationships with some fidelity. Although …
Page 1 of 2