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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Preening behaviour in laying hens : its control and association with other behaviours

Sandilands, Victoria January 2001 (has links)
No description available.
2

Psittacine beak and feather disease : vaccination, haematological response and PCR methodology /

Bonne, Nicolai Johnsen. January 2009 (has links)
Thesis (Ph.D.)--Murdoch Unuiversity, 2009. / Thesis submitted to the Faculty of Health Sciences. Includes bibliographical references (leaves 180-189)
3

Genetic and environmental factors influencing the behaviour and health of laying hens with emphasis on feather pecking

Ramadan, Sameh Gad Abdel-Hak 11 December 2007 (has links) (PDF)
The aim of this work was to investigate the effects of feather availability and imprinting to loose feathers in the litter on the incidence of feather pecking behaviour (FP), condition of the integument and fear reactions in two genotypes of laying hens. Hens that were deprived from loose feathers in the litter (feathers were collected 4 times/week) exhibited a significantly less rate of feather pecking, less number of severe FP and showed a better feather score in the laying period compared to the control groups (no feather treatment) in both Lohmann Tradition (LT) & Lohmann Silver (LS) genotypes. Addition of brown feathers to the floor in LT hens (feathers were added once/week) was associated with a reduction in feather pecking rate, the severe form of this behaviour and improved plumage and skin conditions. Contrary, the addition of white feathers to the floor in LS was associated with the highest rate of feather pecking, the highest severe form of this behaviour as well as the worst feather and skin conditions in the laying period compared to other groups of the same genotype. The LT birds in all feather treatments had a better feather cover than the LS birds. Hens that were imprinted to loose feathers in the litter in the rearing period exhibited a higher rate of FP, higher number of severe FP and showed the worst feather and skin conditions when feathers were collected from the floor during the laying period. Also, these hens reacted more fearful during the tonic immobility test. It is concluded that loose feathers may play a role in the development of feather pecking behaviour in laying hens. Large differences between genotypes were found in respect to the availability of loose feathers, feather pecking and plumage and integument condition. Imprinting of chicks to loose feathers from the floor may affect the incidence of feather pecking later on. Ziel dieser Arbeit war es, die Einflüsse des Federangebotes und der Prägung auf lose Federn in der Einstreu auf die Häufigkeit des Auftretens von Federpicken (FP), den Zustand des Integuments und die Furchtreaktionen an zwei Legehennengenotypen zu untersuchen. Hühnern beider untersuchter Genotypen (Lohmann Tradition (LT) und Lohmann Silber (LS)), denen die losen Federn 4 mal/ Woche aus der Einstreu abgesammelt wurden, zeigten eine geringere Federpickrate, eine geringere Anzahl der schweren Form des FP und eine bessere Gefiederbeschaffenheit in der Legeperiode verglichen mit der Kontrollgruppe (keine Federbehandlung). Das Hinzufügen brauner Federn zur Einstreu bewirkte bei LT Hennen eine Reduktion der FP-Rate, der schweren Form des Federpickens und verbesserte die Gefieder- und Hautbeschaffenheit. Dagegen führte das Hinzufügen weißer Federn in die Einstreu während der Legeperiode bei LS Hennen zur höchsten Federpickrate und Anzahl der schweren Form des Federpickens sowie zur schlechtesten Gefieder- und Hautbeschaffenheit im Vergleich zu anderen Gruppen des gleichen Genotyps. Hühner der LT Linie wiesen in allen Federbehandlungen eine bessere Befiederung als die LS Hühner auf. Hennen, die während der Aufzuchtsperiode auf lose Federn in der Einstreu geprägt wurden, zeigten nach Absammeln der Federn während der Legeperiode eine erhöhte FP-Rate mit einer erhöhten Anzahl der schweren Form des FP und die schlechteste Gefieder- und Hautbeschaffenheit. Außerdem reagierten diese Hühner ängstlicher während des Tests auf tonische Immobilität. Es kann geschlussfolgert werden, dass lose Federn in der Einstreu eine Rolle bei der Entwicklung des Federpickverhaltens von Legehennen spielen und dass Federpicken als Futtersuchverhalten interpretiert werden kann. Grosse Unterschiede zwischen den Genotypen bestanden hinsichtlich der Verfügbarkeit von losen Federn in der Einstreu, des Federpickens sowie der Gefieder- und Integumentbeschaffenheit. Eine Prägung der Junghennen auf lose Federn in der Einstreu könnte das Auftreten von Federpicken zu einem späteren Zeitpunkt beeinflussen.
4

Gonad distribution and reproductive season of feather stars in Kenting, southern Taiwan

Chen, Yi-ting 10 January 2009 (has links)
Gonads are distinct organs in organisms with complicated reproductive systems, and they have specific locations in the body. The gonads of crinoids, however, are scattered in numerous genital pinnules of their arms. We studied seven species of feather stars, Comatella maculata (Carpenter, 1888), Comatella nigra (Carpenter, 1888), Comaster multifidus (M􀎏ller, 1841), Comaster distinctus (Carpenter, 1881), Comanthus parvicirrus (M􀎏ller, 1841), Colobometra perspinosa (Carpenter,1881) and Himerometra magnipinna Clark, 1908 collected at Kenting, southern Taiwan in 2007. The purpose is to explore if the distribution patterns of gonads are adaptative. With bimonthly samplings in a year, it is discovered that the spawning seasons of the species are not synchronized in a particular season. Three models of relationships between maximum arm lengths and numbers of arms exist in the seven species, i.e., constant arm numbers, linear, and quadratic with an asymptote of arm numbers. Therefore, the maximum arm length is more appropriate than arm number as a size index of feather stars. Evidence of bigger mature than immature individuals is found in Comatella maculata, Comaster distinctus and Comaster multifidus, and there is no size difference between males and females. The gonads of feather stars are distributed in the proximal end of arms. The proportion of arms represented by genital pinnules within individuals were constant except in Comanthus parvicirrus where a negative correlation was found. Except the 2 cave-dwelling species, Comatella maculata and Comanthus parvicirrus, most regenerating arms of 5 other species had breakage points occurred near the proximal ends of the arms. Distal breakage may regenerate too fast to recognize. The arms obviously do not grow so fast as to limit gonad development to the proximal ends of arms. Habitat difference may cause variation in genital pinnule widths, but not in the number of genital pinnules as suggested by comparsions of specimens between 2 sites. The cave-dwelling Comanthus parvicirrus has special congregated long arms, which are extended outside. Moreover, these arms have higher probability of breakage, and smaller ranges of genital pinnules than short arms. This phenomenon supports that the limited gonad distribution is adaptive for reducing loss upon arm breakage.
5

Studies of beak and feather disease virus infection

khalesi20022002@yahoo.com, Bahman Khalesi January 2007 (has links)
The circovirus Beak and feather disease virus (BFDV) causes psittacine beak and feather disease (PBFD) that is characterised by a chronic disease process associated with feather abnormalities, beak deformities and eventual death in various species of birds in the order Psittaciformes. This disease is seen in captive and wild psittacine species in Australia and several other countries and is a significant threat to the survival of some endangered psittacine species. This thesis reports on genetic studies that have furthered the understanding of the diversity of BFDV present within Australia. These studies have optimised methods of detecting BFDV. They have also resulted in the production of an immunogenic and antigenic recombinant BFDV Capsid protein that could lead to alternate methods of producing viral antigen for serological tests and the development of a BFDV vaccine. To assess the optimal method of the detection of BFDV infection, feather and blood samples were submitted by referring veterinarians throughout Australia from psittacine birds tentatively diagnosed with PBFD or with a history of being in contact with PBFD-affected birds. These samples were examined by 3 procedures commonly used to detect BFDV infection: a polymerase chain reaction (PCR) assay and haemagglutination (HA) for the detection of virus, and haemagglutination inhibition (HI) tests for the detection of virus antibody in response to infection. Of the samples examined from 623 psittacine birds, the prevalence of BFDV DNA in feather samples detected by PCR was 18.85%. There was a strong correlation between PCR and HA testing of feather samples, although possible false-positive and false-negative PCR and HA results were obtained in some samples. Of the 143 birds that were PCR feather-positive only 2 had detectable HI antibody and these birds were also HA feather-negative, which suggests that they were developing immunity to recent infection. All birds with HI antibody were feather HA negative. Despite the rare occurrence of PBFD in cockatiels (Nymphicus hollandicus), 2 of the 13 samples collected from this species were PCR and HA positive indicating that this species can be infected with BFDV. Three studies were undertaken to further our understanding of the genetics of BFDV in Australian avifauna: sequence analysis of the BFDV detected in a grey cockatiel (Nymphicus hollandicus), a species normally considered resistant to infection with BFDV; analysis of the genome of BFDV present in lorikeets (Trichoglossus sp.) in Australia; and analysis of the genome of BFDV detected in endangered swift parrots (Lathamus discolor). Sequence analysis of the entire genome of the cockatiel BFDV isolate revealed that it clustered phylogenetically with 2 other viruses, one from a sulphur crested cockatoo (SCC1-AUS) and one from a Major Mitchell cockatoo (MMC-AUS), which suggests that this isolate from the grey cockatiel was not a cockatiel-specific biotype. Phylogenetic analysis of the ORF V1 of BFDV detected in 7 lorikeets demonstrated these 7 isolates clustered phylogenetically with other BFDV isolates obtained from Loriidae species elsewhere in the world and confirmed the presence of a loriid-specific genotype. Phylogenetic analysis of the sequence data generated from ORF V1 of virus detected in 2 endangered swift parrots provided evidence they were also infected with BFDV genotypes derived from other species of birds, one isolate clustering with viruses from a Loriidae genotype and the other with isolates derived from species of Cacatuidae and Psittacidae. As part of this research, a baculovirus expression system was successfully developed for the production of recombinant BFDV Capsid protein. Inoculation of this protein into chickens resulted in the development of HI antibody, which demonstrated its immunogenicity. When used as an antigen in HI tests it detected antibody in virus-infected birds, which demonstrated its antigenicity. This protein offers potential application as an antigen for the development of serological tests and as an immunogen for incorporation into vaccines for control of PBFD.
6

Studies of beak and feather disease virus infection /

Khalesi, Bahman. January 2007 (has links)
Thesis (Ph.D.)--Murdoch University, 2007. / Thesis submitted to the Division of Health Sciences. Includes bibliographical references (p. 124-143).
7

Development of novel diagnostic and vaccine options for beak and feather disease virus (BFDV) /

Shearer, Patrick. January 2008 (has links)
Murdoch University (Ph.D.)--Murdoch University, 2008. / Contains three published journal articles at back of thesis. Thesis submitted to the Faculty of Health Sciences. Includes bibliographical references (leaves 196-231)
8

Sarconema eurycerca (Wehr) : the heartworm of swans and the role of Trinoton anserinum (F) as an intermediate host

Cohen, Sharon January 1988 (has links)
All filarial nematodes of the family Onchocercidae are parasites of vertebrates and require intermediate insect hosts for completion of their life-cycles. Eighteen genera within this family are known to infect birds but very few of the associated intermediate hosts have been elucidated. Sarconema eurycerca (Wehr) is a filarial nematode of swans and geese. A recent study of S. eurycerca in American Whistling Swans (Cygnus c. columbianus ) has demonstrated that the intermediate insect host is a feather louse, Trinoton anserinum (Fabricius) (Seegar, 1977). The main aim of the present study was to investigate the relationship between S. eurycerca and British swans and to determine whether T. anserinum is the intermediate host of the parasite in this country. A total of 1128 swans (of all species) were examined from sites in Britain, Denmark and Iceland. Infected swans were detected by examining blood samples for larval stages of S. eurycerca (microfilariae) using a new sedimentation technique developed in the study. An overall incidence of 15.0% was recorded with a significantly higher proportion of juvenile swans being infected. The microfilariae of S. eurycerca exhibited a diurnal sub-periodic rhythm within the host, with maximum counts occurring between 11.00 and 19.00 hours in the peripheral blood supply. T. anserinum was found to satisfy all the attributes required of an intermediate insect host. As an obligate ectoparasite, T. anserinum has a close spatial and temporal relationship with the swan. T. anserinum appears to be capable of ingesting microfilarie of S. eurycerca whilst feeding on blood. All developing larval stages of S. eurycerca were found in T. anserinum and the louse was very mobile and capable of transmitting the nematode from one swan to another. Examinations were made of the nematode, its morphology and pathological effects on both heart tissue and blood components of the swan. Significantly higher lymphocyte percentages and lower eosinophil percentages, haematocrit and red blood corpuscle counts were recorded in swans infected with S. eurycerca.
9

The Adventures of Eagle Feather: A Collection of Stories

Goebel, Luke B 01 January 2010 (has links) (PDF)
Luke Goebel wrote this collection of fiction in his final year enrolled at the M.F.A. Program for Poets and Writers at the University of Massachusetts Amherst. These stories were wrought after studying with Sam Michel, Noy Holland, as well as other faculty members at UMass Amherst, and after a summer of study with Gordon Lish. The themes that recur throughout these stories are: fathers, America, Bald Eagles, feathers, Native American mythology and legend (obsession with Native Culture), as well as sex and sexual awakening/revulsion, and, of course, the road.
10

Biomimicry of Feathers for Airport Design

Park, Sarah S. 10 October 2017 (has links)
No description available.

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