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Denk, Angelika. "Male and Female Reproductive Tactics in Mallards (Anas platyrhynchos L.)." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-42673.
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Lacombe, A. M. A. "Effects of circulating catecholamines on diving in ducks (Anas platyrhynchos)." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30724.
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Plasma catecholamines have been measured in chronically adrenalectomised (ADX) ducks, in chronically adrenal denervated ducks (DNX), in their respective sham-operated controls (SH-adx, SH-dnx) as well as in intact ducks after 3 minutes forced submergence. The results showed that 100% of the plasma Epinephrine (EP) and 40 to 80% of plasma Norepinephrine (NE) released during the dive came from the adrenal glands. 20 to 60% of plasma NE came from endings of the autonomic vascular sympathetic nerves which are strongly stimulated during diving.
Adrenal catecholamines were released by nerve activation only; non neural mechanisms did not play any role in their release.
Maximum dive times (MDT) in chronically adrenalectomised ducks (ADX: 5 min. 19 ± 20 sec.) and in chronically adrenal denervated ducks (DNX: 7 min. 10 ± 13 sec.) were significantly
lower than in sham-operated controls (respectively SH-adx: 9 min. 58 ± 45 sec., SH-dnx: 12 min. 10 ± 28 sec). Venous infusion of catecholamines in ADX and DNX during the dive increased MDT: MDT of DNX ducks perfused with catecholamines (9 min. 46 ± 20 sec.) were significantly higher than in DNX perfused with saline (7 min. 21 ± 17 sec.), but did not reach the MDT observed in the SH-dnx: other adrenal products must be involved. Diving heart rates of ADX and DNX (at 4 min. dive respectively: 62 ± 16 and 31 ± 2 beats/min.) were significantly
higher than in their sham-operated controls (23 ± 3 and 17 ± 2 beats/min.) . Blood pressure during the dive was signifi-
cantly lower in ADX and DNX (at 4 min. dive respectively: 93 ± 8 and 98 ± 4 mmHg) compared with their sham-operated controls (131 ± 12 and 118 ± 6 mmHg). Infusion of catecholamines in DNX raised blood pressure towards SH-dnx values, but there was no change in heart rate. PaO₂, CaO₂, pHa and lactate levels in DNX (respectively: 42 ± 2 mmHg, 4.5 ± 0.8 ml 02 /100ml blood, 7.233 ± 0.016, 3.1 + 0.3 mM) were significantly lower than in SH-dnx after 5 minutes submergence (53 ± 1 mmHg, 6.8 ± 0.4 ml 02 /100 ml blood, 7.301 ± 0.007, 4.8 + 0.4 mM). There was also a significant increase of plasma N⁺ (+ 5.4 ± 1.7 mEq/L) in SH-dnx after 5 minutes submergence, but this was not the case in DNX where it was K⁺ (+ 1.1 ± 0.4 mEq/L) which increased. This suggested that adrenal catecholamines increase tolerance to underwater submersion by enhancing peripheral vasoconstriction,
thus preserving the O₂ stores for the heart and brain. Moreover, they may affect the acid-base equilibrium during diving by increasing the activity of the Na⁺K⁺ pump and may also have a direct effect on the rate of glycogenolysis.
Preventing the actions of catecholamines on the heart by injecting beta-blocker during forced submersion did not decrease
MDT; however the cardiovascular response was markedly affected. During beta-blockade, diving heart rate rose steadily
from 24 ± 6 beats/minute after 2 minutes to 52 ± 8 beats/minute after 6 minutes diving. In contrast, heart rates remained close to the levels reached at 2 minutes (17 ± 3 and 19 ± 4 beats/minute) throughout the control dives.
Perfusion pressure and blood flow have been recorded simultaneously in both hind limbs of ducks. One leg was perfused
with different blood mixtures devoid of catecholamines (Test leg) and compared with the other, perfused with the ducks'own blood (autoperfused leg). This showed that hyper-capnia has a depressant effect on the neural component of the peripheral vasoconstriction. Perfusion of test legs with hypoxic-hypercapnic blood to which catecholamines were added, showed that circulating catecholamines are needed to increase peripheral vasoconstriction during diving.
In summary, during forced submergence circulating catecholamines,
released mainly by the adrenal glands, compensate
for the depressant action of hypercapnia on the neural component of peripheral vasoconstriction. Maintenance of this peripheral vasoconstriction during forced diving ensures that O₂ stores are not wasted on peripheral tissues, and this explains how MDT is prolonged.<br>Science, Faculty of<br>Zoology, Department of<br>Graduate
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Cunningham, Emma Jane Ann. "Forced copulation and sperm competition in the mallard Anas platyrhynchos." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262851.
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Cnotka, Julia. "Hirnveränderungen bei domestizierten Landenten (Anas platyrhynchos f.d.)-morphometrische und ethologische Untersuchungen." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982291108.
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Gunnarsson, Gunnar. "Survival patterns and density-dependent processes in breeding mallards Anas platyrhynchos." Doctoral thesis, Umeå : Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200712.pdf.
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Åkerstedt, Lovisa. "Intraspecifik aggression mellan gräsänder (Anas platyrhynchos) i urbana och rurala habitat." Thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-84260.
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The continuing increase in urbanization is changing the natural habitats of wild animals. Some wildlife have colonized urban areas and are exposed to new stimuli to which they respond differently: some species adapt whereas others thrive. Living in such an environment can lead to increased stress and elevated aggression. The purpose of this study was to examine the intraspecific aggression among mallards (Anas platyrhynchos) in two habitats with different degree of urbanization. Field observations were performed on groups of mallards in urban and rural environments. I predicted that there would be more aggressive behavior among mallards in urban than in rural habitats, based on the hypothesis that increased stress in an urban environment results in elevated aggression. Aggression was defined as the number of attacks, which was classified as chases, nips, and threats. I observed on average more than three times as many attacks (chases, nips and threats) in urban as in rural habitats. In addition, more females relative to males in the groups resulted in more attacks. Wild birds are important to flora, fauna, and man. Because high aggression can affect the fitness of wild urban animals negatively through, for example, physical injuries and increased disease transmission during fights, it is important that humans intervene to prevent this.<br>Den fortsatta ökande urbaniseringen förändrar vilda djurs naturliga habitat. Vissa vilda djur har koloniserat urbana områden och utsätts för nya stimuli som de responderar olika på: somliga arter anpassar sig medan andra frodas. Att leva i en sådan miljö kan leda till ökad stress och förhöjd aggression. Syftet med denna studie var att undersöka den intraspecifika aggressionen mellan gräsänder (Anas platyrhynchos) i två habitat med olika nivå av urbanisering. Fältobservationer genomfördes på grupper av gräsänder i urbana och rurala miljöer. Jag förväntade mig att det skulle förekomma fler utdelade attacker bland gräsänder i urbana än i rurala habitat, baserat på hypotesen att ökad stress i en urban miljö resulterar i förhöjd aggressivitet. Aggression definierades som antalet utdelade attacker, vilket klassificerades till jagningar, nyp och hot. Jag observerade i medel mer än tre gånger så många attacker (jagningar, nyp och hot) i urbana som i rurala habitat. Utöver detta resulterade fler honor relativt hanar i grupperna i fler attacker. Vilda fåglar är viktiga för flora, fauna och människa. Eftersom hög aggression kan påverka vilda urbana djurs fitness negativt genom till exempel fysiska skador och ökad sjukdomsöverföring vid strid, är det viktigt att människan ingriper för att förhindra detta.
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Cruz, Tiago Miguel Regateiro. "Censo de aves aquáticas em Mira e nidificação de Anas platyrhynchos." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/7923.
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Mestrado em Biologia Aplicada<br>Este trabalho foi desenvolvido em duas lagoas de Mira que pertencem à Rede Natura 2000 e teve como principais objectivos monitorizar as espécies de aves aquáticas e estudar a reprodução do Pato-real (Anas platyrhynchos).
A monitorização de aves aquáticas foi efectuada com o propósito de avaliar a variação mensal de aves nas 2 lagoas existentes na área de estudo, por forma a obter informação útil para a gestão e ordenamento da zona, bem como para a preservação das espécies. No desenho experimental idealizado optou-se por efectuar quatro contagens por mês em cada lagoa (semanalmente), por forma a avaliar o efeito do aumento de esforço de monitorização em relação a anos anteriores. Os resultados revelaram que a zona de estudo tem uma importância significativa como zona de invernada de aves aquáticas.
Algumas espécies apresentam populações residentes estáveis que, sazonalmente, vêm o seu número de indivíduos variar com a chegada e partida de aves migradoras.
Com o estudo da reprodução do Pato-real desejou-se obter informação útil para a administração desta relevante espécie cinegética. Para tal, procedeu-se à monitorização da população reprodutora na área de estudo. Sendo a barrinha uma zona de refúgio no período cinegético, de reprodução e de muda para a espécie, realizou-se uma avaliação do sucesso reprodutor e de predação de ninhos. Obteve-se uma taxa média de sucesso reprodutor de 37%. Os resultados relativos aos ninhos reais e ao estudo com ninhos simulados revelaram percentagens de predação de 57%.<br>Waterfowl monitoring in “Mira” Natura 2000 Site: a contribute towards their management. The aim of this work was to monitorize waterfowl populations and to study the reproduction of the Mallard (Anas platyrhynchos).
The waterfowl monitoring was carried out to gather standardized information on monthly populations fluctuations in the 2 lagoons existent in the study area. This information is needed for proper management and wildlife conservation. The experimental design included 4 counts per month (one per week) in each lagoon, to allow an evaluation of the monitoring effort increase comparatively to past years.
The results showed that the study area is an important wintering area for waterfowl. Some species have resident individuals, but their populations are dynamic and vary with the arrivals and departures of migratory birds.
The aim of the Mallard reproduction study was to collect useful information to this important species management. Thus breeding bird surveys were conducted to this species, at the study area. As the Barrinha is a refugee area during the hunting season, a breeding and moulting area for the Mallard, a reproductive success survey and nest predation evaluation were developed. It was obtained an average rate of breeding success of 37%. The results relative to real nests surveys and the false nests study revealed about 57% of predation.
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Lusimbo, Wanjala Simiyu. "Toxicity of Prudhoe Bay crude oil to mallard duck (Anas platyrhynchos) embryos." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0019/NQ43517.pdf.
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Simões, Karina. "Ciclo reprodutivo anual e caracteristicas morfologicas testiculares do pato domestico (Anas platyrhynchos)." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316734.
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Orientador: Antonio Orsi<br>Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia<br>Made available in DSpace on 2018-08-04T00:24:17Z (GMT). No. of bitstreams: 1
Simoes_Karina_D.pdf: 5008621 bytes, checksum: 052a8d69de71694b3bfdb0e3ffdcc5b0 (MD5)
Previous issue date: 2004<br>Resumo: Em aves, a reprodução é um processo cíclico definido, onde a cada ano os órgãos reprodutores crescem e regridem sob a influência de fatores ambientais. Durante o processo de maturação das gônadas e reprodução, o organismo do animal mobiliza energia intensamente. O processo reprodutivo é bem elaborado, incluindo operações especializadas como produção, maturação e liberação de gametas, bem como a síntese de hormônios esteróides sexuais e comportamento sexual. O objetivo do estudo foi conhecer a morfologia testicular do pato doméstico (Anas platyhrynchos) e estabelecer seu ciclo reprodutivo anual, relacionando-o ao nível do hormônio testosterona e a alguns parâmetros do metabolismo
energético interligados ao processo reprodutivo. Para isto foram utilizados 36 animais, sendo coletados testículos de 3 animais por mês, visando a descrição morfológica e o estabelecimento do ciclo reprodutivo anual da espécie por meio de microscopia de luz e análise morfométrica. Os espermatozóides foram analisados através de microscopia eletrônica de transmissão e de varredura. Os níveis de testosterona plasmática total foram
dosados mensalmente por meio do ¿Kit Cout-A-Count (DPC)¿ e os níveis de glicose sangüínea pelo método colorimétrico. Também foram dosados o glicogênio hepático e muscular pelo método Glicogênio Trinder e lipídeos totais hepático e muscular pelo método de extração com solvente orgânico. O ciclo reprodutivo anual do pato doméstico é caracterizado por quatro fases distintas, se iniciando com a fase reprodutiva no começo do inverno (Julho) e com pico da reprodução na primavera (Outubro), apresentando maiores peso e volume testiculares, e maiores diâmetro dos túbulos seminíferos e altura do epitélio seminífero. A fase regressiva ocorre no final da primavera (Novembro) e início do verão (Dezembro). A fase de quiescência ou repouso testicular é observada durante o verão (Janeiro, Fevereiro), sendo sucedida pela fase de recrudescência que ocorre no outono
(Março a Junho), correspondendo à fase mais longa do ciclo. O processo completo da espermatogênese em termos de maturação dos spermatozóides e a espermiação foram notados durante a fase reprodutiva, coincidindo com o pico de testosterona plasmática. Os espermatozóides são caracterizados pela presença de cabeça, curta peça intermediária e uma longa peça principal. No conjunto os espermatozóides são longos, filiformes e cilíndricos. O espermatozóide do pato doméstico é similar ao de outras aves nãopasseriformes correspondendo a um tipo básico de espermatozóide. Concernente ao metabolismo energético somente a glicose sangüínea estava correlacionada ao ciclo reprodutivo anual da espécie, fornecendo energia para o processo reprodutivo<br>Abstract: In birds, reproduction is a defined cyclic process; in which each year the reproductive organs grow and regress under the influence of environmental factors. During the process of gonadal maturation and reproduction, the organism of the animal intensively mobilizes energy. The reproductive process is well elaborated, including specialized operations such as the production, maturation and release of gametes, as well as the
synthesis of sex steroid hormones and sexual behavior. The aim of the present study was to determine the morphology of the testes of the domestic duck (Anas platyrhynchos) and to establish its annual reproductive cycle, correlating it with testosterone levels and some parameters of energy metabolism associated with the reproductive process. Using a total of 36 ducks, testes were collected from 3 animals per month, and the morphology and annual reproductive cycle of the species were determined by light microscopy and morphometric analysis. Spermatozoa were analyzed by transmission and scanning electron microscopy. Total plasma testosterone levels were measured monthly using the Cout-A-Count (DPC) kit and blood glucose levels were determined by a colorimetric method. Hepatic and muscle glycogen was measured by the Trinder glycogen method and total hepatic and muscle lipids using extraction with organic solvents. The annual spermatogenic cycle of the domestic duck is characterized by four distinct phases, starting with the reproductive phase at the beginning of winter (July) and peak reproduction in spring (October), with higher testicular
weight and volume, a larger seminiferous tubular diameter and greater seminiferous epithelium height being observed during these periods. The regressive phase occurs at the end of spring (November) and the beginning of summer (December). The phase of quiescence or testicular resting is observed during summer (January, February), followed by the phase of recrudescence that occurs in autumn (March to June), corresponding to the
longest phase of the cycle. The complete process of spermatogenesis in terms of spermatozoon maturation and spermiation is noted during the reproductive phase, coinciding with peak plasma testosterone levels. The spermatozoa are long, filiform and cylindric and are characterized by the presence of a head, short middle piece and long principal piece. The spermatozoon of the domestic duck resembles that of other nonpasseriform
birds, corresponding to the basic type of spermatozoon. Considering energy metabolism, only blood glucose was correlated with the annual reproductive cycle of the domestic duck, providing energy for the reproductive process<br>Doutorado<br>Anatomia<br>Doutor em Biologia Celular e Estrutural
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Cabral, Liliane Ferreira. "Vacinação de patos-reais (Anas platyrhynchos) contra a gripe aviária em Portugal." Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2009. http://hdl.handle.net/10400.5/1243.
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Dissertação de Mestrado Integrado em Medicina Veterinária<br>Na última década, a estirpe asiática H5N1 de alta patogenicidade disseminou-se rapidamente
pela Ásia, Europa e África, resultando no morticínio de mais de 250 milhões de aves
domésticas e na morte de mais de duas centenas de pessoas, representando uma séria ameaça
à Saúde Pública. Os patos, especialmente o pato-real (Anas platyrhynchos), desempenham um
papel importante na amplificação e na disseminação do vírus. Por conseguinte, a
disponibilização de vacinas que sejam eficazes nesta espécie em condições “de campo”
constitui-se como uma ferramenta importante no controlo do vírus.
O presente estudo baseia-se no programa de monitorização serológica incluído nos planos de
vacinação de emergência e de vacinação preventiva implementados na sequência de um foco
de gripe aviária de baixa patogenicidade, subtipo H5N2, ocorrido numa exploração cinegética
nacional em Setembro de 2007. A vacinação com duas vacinas inactivadas bivalentes,
H5N9/H7N1 e H5N6/H7N7, foi realizada em dois grupos de patos-reais. Posteriormente, foi
realizada uma revacinação semestral num destes grupos. A vacinação induziu um título de
anticorpos específicos para a hemaglutinina H5 similar nos dois grupos de patos
primovacinados, acima do limiar considerado de protecção (4 log2) até pelo menos 16
semanas após a administração do reforço da vacina, tendo-se atingido uma taxa de
imunização inicial superior a 80%. A revacinação semestral com o antigénio H5N6 induziu
uma resposta humoral pouco exuberante, com persistência de anticorpos protectores apenas
até 6 semanas após vacinação. O antigénio de subtipo H7N7 não estimulou o
desenvolvimento de uma resposta imunitária humoral protectora para a hemaglutinina H7.
Pelo contrário, o antigénio H7N1 induziu um título médio de anticorpos ligeiramente acima
do limiar de protecção, que persistiu até pelo menos 26 semanas após o reforço da vacina. Os
resultados observados sugerem que numa exploração cinegética deste tipo, em que o risco de
contacto com o vírus “de campo” é muito elevado, a revacinação semestral com uma vacina
adequada é uma medida complementar importante para limitar a ocorrência de focos
secundários da infecção/doença.<br>ABSTRACT -
Vaccination of Mallard Ducks (Anas platyrhynchos)
against Avian Influenza in Portugal --
During the last decade, HPAI H5N1 has rapidly spread across Asia, Europe and Africa,
leading to the culling of more than 250 million birds and the death of more than two hundred
people, posing a serious threat to public health. Ducks, particularly, mallards (Anas
platyrhynchos), play an important role in the amplification and spread of the virus. Vaccines
that are effective in this species in field conditions will provide an important tool for control
of the disease.
This study is based on a serological monitoring programme included in the emergency and
preventive vaccination plans applied following a LPAI H5N2 outbreak in a game bird holding
in Portugal, in 2007. Vaccination with two bivalent, H5N9/H7N1 and H5N6/H7N7,
inactivated vaccines was carried out in two groups of mallard ducks. A second vaccination,
six months later, was also carried out in one of these groups. The first vaccination induced a
similar mean antibody titer specific for H5 hemagglutinin in both groups, above the protective
threshold (4 log2) and persistent for at least 16 weeks after the vaccine boost. The proportion
of immunized ducks was initially above 80%. Ducks revaccinated six months later with the
H5N6 vaccine showed a lower antibody response, which persisted for only 6 weeks after
vaccination. The H7N7 vaccine antigen did not simulate a protective immune humoral
response specific for H7 hemagglutinin. On the contrary, the mean antibody titers following
vaccination with the H7N1 vaccine were slightly above the threshold, persisting for at least 26
weeks after the boost. These results suggest that semestral vaccination with an adequate
vaccine is as important additional measure to limit secondary AI outbreaks in this type of
farming system, which is at a particularly high risk of exposure to the field virus.
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Barra, Inostroza Marlene. "Olika faktorer som styr gräsandhanars (Anas platyrhynchos) ruggningsperiod mellan prakt- och eklipsdräkt." Thesis, Högskolan i Halmstad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-43307.
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Khabazi, Ali. "Anatomie comparée du développement du système ostéo-musculaire des oiseaux : implications des contraintes fonctionnelles sur la croissance." Thesis, Paris, Muséum national d'histoire naturelle, 2017. http://www.theses.fr/2017MNHN0008.
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Nous avons étudié l’impact de contraintes mécaniques contrastées sur la structure des pattes de canard (Anas platyrhynchos) pour comprendre l’influence de l’environnement sur la variabilité phénotypique. Des canards ont été élevés sous quatre conditions expérimentales: 1/ marche restreinte, 2/ marche libre 3/marche augmentée 4/ marche et nage. Les vingt-huit muscles et les trois os longs de la patte de ces oiseaux ont été mesurés. Une comparaison a été faite entre les appareils locomoteurs des canards des cailles et des pies pour établir un lien entre les types de marche et la morphologie des pattes. Les résultats montrent que les muscles sont principalement affectés par une restriction de mouvement, alors que les os sont principalement touchés par une augmentation de l’exercice. Les variations de forme des os touchent principalement le genou. Cette articulation est aussi celle qui montre la plus de variabilité au cours de la locomotion des différentes espèces comparées<br>We investigated the impact of contrasting mechanical constrains on duck leg structure (Anas platyrhynchos) to understand the influence of the environment on phenotypic variability. Ducks were raised under four experimental conditions: 1/ restricted walking, 2/ free walking 3/ increased walking 4/ walking and swimming. The twenty-eight muscles and three long bones of the leg of these birds were measured. A comparison was made between locomotive devices of quail, ducks and magpies to establish a link between the types of walking and the morphology of the legs. The results show that the muscles are mainly affected by a restriction of movement, while the bones are mainly affected by an increase in exercise. The variations in the shape of the bones mainly affect the knee. This joint is also the one that shows the most variability during the locomotion of the different compared species
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Wilberg, Claudia. "Untersuchungen zur Inhalationsnarkose mit Isofluran sowie mit Buprenorphinprämedikation bei der Warzenente (Anas platyrhynchos)." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-41606.
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Remy, Felix Benedikt. "Tiergerechte Wasserversorgung von Pekingenten (Anas platyrhynchos f. domestica) unter dem Aspekt Tierverhalten und Tiergesundheit." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-41761.
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Smith, Frank Melvin. "Arterial baroreceptor control of the circulation during forced dives in ducks (Anas Platyrhynchos var.)." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27533.
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When dabbling ducks are involuntarily submerged, arterial vasoconstriction produces a large increase in the peripheral resistance to blood flow which is balanced by a decrease in output of the heart, and arterial blood pressure is maintained. Arterial baroreceptors sense systemic blood pressure, and provide the afferent information to the baroreflex for pressure regulation. The effector limbs of the baroreflex are the same as those involved in the diving responses, and the baroreceptors are likely to be important in the integration of the cardiovascular responses to diving. The purpose of this study was to investigate the role of the arterial baroreceptors in maintaining blood pressure during diving, and in the initiation and maintenance of the diving responses.
Baroreceptor function was studied by diving ducks at various times after barodenervation, and by electrically stimulating the central end of one baroreceptor nerve in baroreceptor-denervated animals to simulate a controlled baroreceptor input before and during submersion.
Intact baroreceptor innervation was not necessary for the development of peripheral vasoconstriction, but loss of the baroreceptors modified the cardiac response to submersion by impairing the vagally mediated bradycardia. There was no effect of baroreceptor nerve stimulation on peripheral
resistance during diving, and the baroreflex operated via the heart rate in modulating blood pressure early in the dive. Later in the dive, stimulation was ineffective in altering either heart rate or blood pressue. Strong chemoreceptor drive results from decreased blood oxygen and increased carbon dioxide levels in the dive, and the results of experiments to determine the mechanism of baroreflex attenuation showed that an interaction between chemoreceptor and baroreceptor inputs may be at least partly responsible for reducing baroreflex effectiveness.
The main conclusion from this work is that the arterial baroreceptors contribute to the diving responses through modulation of heart rate, to help balance the fall in cardiac output against the baroreceptor-independent peripheral vasoconstriction in the first minute of forced dives.<br>Science, Faculty of<br>Zoology, Department of<br>Graduate
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Jax, Elinor [Verfasser]. "Immunology going wild : genetic variation and immunocompetence in the mallard (Anas platyrhynchos) / Elinor Jax." Konstanz : KOPS Universität Konstanz, 2019. http://d-nb.info/1189593912/34.
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Whitehead, John Gardner. "An examination of the kinematics and behavior of mallards (Anas platyrhynchos) during water landings." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/99383.
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This dissertation aims to address how a change in landing substrate may change landing kinematics. To examine this possibility, mallards (Anas playtrhynchos) were used as a study species and 177 water landings were recorded through the use of two camera systems with photogrammetric capabilities. This enabled the landing trajectory and landing transition kinematics to be tracked in three dimensions. From the resulting position data three questions were pursued. Do mallards regulate landing kinematics through a ̇-constant strategy? With what kinematics do mallards land on water? Do landing kinematics respond to external factors, such as an obstacle to landing? Chapter 2 assesses the presence of a ̇-constant regulatory strategy and compares the implementation to other landing behaviors. Chapter 3 examines the variation observed in the landing kinematics of mallards, identifies the primary kinematic drivers of that variation, and detects differences in kinematic profile. Chapter 4 inspects the landing kinematics combined with the positions of all other waterfowl in the vicinity to test for the presence of obstacle avoidance behavior.<br>Doctor of Philosophy<br>Control of landing is an important ability for any flying animal. However, with the exception of perch landing, we know very little about how birds and other flyers land on a variety of different surfaces. Here, we aim to extend our knowledge in this area by focusing on how mallard ducks land on water. This dissertation addresses the following questions. Do mallards regulate landing speed and trajectory the same way as pigeons? At what speeds, angles, and postures do mallards land on water? Can mallards adjust landing behavior to avoid collisions with other birds on the water surface? Chapter 2 determines how mallards regulate landings and how it is similar and different from pigeons and several other flyers. Chapter 3 describes the speeds, angles, and postures used by mallards to land on water. In addition, this chapter finds evidence for at least two different categories of landing performed by mallards. Chapter 4 provides evidence that mallards avoid situations in which a collision with another bird is likely. However, it is unclear if this is an active choice made by the mallard or due to other circumstances related to the landing behavior. Overall, this dissertation illustrates how the landing behavior of mallards is similar to what has been documented in other animals. However there are significant differences such as higher impact speeds, and shallower angles. Both of which are likely related to the ability of water to absorb a greater amount of the impact forces than a perch or the ground would.
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Champagnon, Jocelyn. "Conséquences des introductions d’individus dans les populations exploitées : l’exemple du Canard Colvert Anas platyrhynchos." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20147/document.
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Le renforcement des populations naturelles exploitées par des individus captifs est rarement évalué, bien qu'il puisse induire des modifications notables sur la population naturelle à de nombreux niveaux : démographie, comportement, morphologie, génétique, pathogènes. Ce travail de thèse concerne les introductions de canards colverts Anas platyrhynchos réalisées à des fins cynégétiques. Cette pratique est très répandue en Europe, depuis plus de trente ans. Du fait de leur domestication en élevage, les canards lâchés subissent une mortalité naturelle très forte comparée aux oiseaux sauvages, à laquelle s'ajoute une plus grande vulnérabilité à la chasse. Une différenciation génétique marquée permet de discriminer les oiseaux lâchés de leurs congénères sauvages. Des croisements entre les deux groupes sont détectés, mais l'introgression reste limitée. Globalement, la contribution démographique et génétique des individus d'élevage à la population sauvage est faible, même si une modification morphologique attribuable aux lâchers a été constatée dans la population sauvage en trente ans. Les conséquences écologiques pour la population réceptrice semblent donc limitées, mais une vigilance continue doit s'exercer concernant la diffusion de pathogènes (forte prévalence occasionnelle de virus Influenza A dans les élevages) et les risques génétiques associés au renforcement sur le long terme<br>The consequences of releasing captive-reared game animals into the wild have received little attention, despite their potential impact for receiving populations in terms of demography, behaviour, morphometrics, genetics and pathogens. The present study considers Mallards Anas platyrhynchos released for hunting purposes, an increasing practice in Europe over the last 30 years. Because of domestication process in game farm facilities, our study shows high natural mortality of these ducks once released compared to wild Mallards, in addition to high vulnerability to hunting. A clear genetic differentiation allows discrimination of released and wild Mallards. Hybridization with wild Mallards exists, but did not result into significant introgression. Generally, genetic as well as demographic contributions of captive-bred birds to the natural population were low, but a morphological modification associated with releases was recorded over 30 years in natural population. Ecological consequences of the releases for the wild population seem to be limited, but caution should be maintained on the possible transmission of pathogens (occasionally high prevalence of avian Influenza A in some breeding facilities) and the genetic risks associated with long-term releases
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Gabbott, Geoffrey Roy Julian. "Neural control of the cardiac response of the Pekin duck (Anas platyrhynchos) to forced submersion." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25783.
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Cardiovascular responses evoked during forced submersion enable the Pekin duck (Anas platyrhynchos) to survive protracted periods of asphyxia. The responses include an extraordinary bradycardia and intense peripheral vasoconstriction with the result that blood flow is favoured to those organs most susceptible to lack of oxygen. These adjustments appear to be mediated via the caudal brainstem following stimulation of peripheral and central arterial chemoreceptors.
The minor role that baroreceptors play in the generation of these responses was demonstrated by the persistence of the cardiovascular changes following peripheral arterial baroreceptor denervation. Isolation of the cephalic
circulation from the systemic circulation enabled a series of experiments to assess the relative contributions from peripheral chemoreceptors, located in the carotid bodies, and from unidentified central chemoreceptors within the cranial circulation. A declining arterial P0₂ in the systemic circulation appeared especially potent in evoking bradycardia during submersion. Increased arterial PC0₂, likewise, resulted in a reduced heart rate. Similar changes in the blood gas levels of the cephalic circulation did not elicit significant bradycardia. However, both receptor groups responded to arterial hypoxic hypercapnia by activating substantial reduction in peripheral blood flow, as reflected by the rise in hind limb vascular resistance. Although baroreceptors may continue to mitigate changes in arterial blood pressure and cause some change in heart rate and vascular resistance, chemoreceptors appear to be predominantly responsible for the changes during submersion.
The cardiac response to chemoreceptor stimulation during submersion was discovered to habituate following repetitive diving. Habituation was so pronounced in some ducks that after several training sessions the bradycardia during 40-second forced dives was abolished. Habituation of the cardiac response appeared dependent on the intensity of chemoreceptor stimulation. With severe arterial hypoxia, produced by either prolonging dive times or by reducing the pre-dive inspired oxygen content, little or no cardiac habituation was observed.
Tests were conducted to demonstrate efficacy of the cardioinhibitory efferent discharge. Maintained sensitivity of chemoreceptors was suggested by the lack of change in oxygen breathing tests before and after training. Furthermore, the persistence of stimulus intensity was established and these observations led to the suggestion that the locus of habituation is within the CNS.
The demonstration that the level of bradycardia was dependent on arterial P0₂ in both naive and habituated animals argues against the contention that the diving response is a fear response. Further evidence against this view was provided by the demonstration that the diving response remains essentially intact following transection in the rostral mesencephalon below the level of the hypothalamus.
It is concluded that chemoreceptor-driven cardiovascular changes evoked as part of the diving response are mediated by regions of the CNS below the rostral brainstem. Modification of these responses can be produced in the intact animal by simple forms of learning. However, it remains uncertain at what level this influence arises.<br>Science, Faculty of<br>Zoology, Department of<br>Graduate
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Dalby, Lars, Pär Söderquist, Thomas K. Christensen, Preben Clausen, Árni Einarsson, Johan Elmberg, Anthony D. Fox, et al. "The status of the Nordic populations of the Mallard (Anas platyrhynchos) in a changing world." Högskolan Kristianstad, Avdelningen för Naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-10140.
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Dabbling ducks (Anas spp.) are importantmigratory quarry species, protected as a shared resource under international legislation. However, there is a lack of sufficient high-quality data on vital demographic rates and long-term trends in numbers to judge the conservation status of many duck populations at the flyway level. In response to reported declines in the North-West European flyway population of theMallard, we compiled available data on this species in the Nordic countries up to 2010. Generally, national breeding numbers showed increasing trends, wintering abundance showed variable trends, and productivitymeasures indicated stable or increasing trends.Major knowledge gaps were identified, namely the size of hunting bags, the influence of the released Mallards and the role of short-stopping in explaining changing patterns of wintering abundance across the North-West European flyway. Numerically the Nordic breeding population appears in “good condition”, and the wintering numbers have been either stable or increasing in the last two decades. The annual number of releases needs to be determined in order to judge the sustainability of the current levels of exploitation. Overall, none of the indicators showed alarming signs for the Mallard population in the Nordic countries when considered in isolation. However, the widespread decline in wintering numbers elsewhere across North-western Europe requires urgent pan-European action.
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Barber, Claire Louise. "Vision and the lighting requirements of ducks (Anas platyrhynchos domesticus) and turkeys (Meleagris gallopavo gallopavo)." Thesis, University of Bristol, 2003. http://hdl.handle.net/1983/5a570dc4-74ab-4c71-b7d0-b185e0e06533.
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In poultry housing where the light environment is provided artificially, it is largely designed to meet the requirements of human vision and poultry production and does not necessarily consider the bird's visual abilities. Extrapolation of research from fowl to other poultry species may be inappropriate, given their different ecological backgrounds. The overall aim of this thesis was to investigate vision in domestic ducks and turkeys and their light requirements. The spectral sensitivity of domestic ducks, domestic turkeys and humans was investigated using a behavioural test. Ducks and turkeys had similar spectral sensitivities, extending into the UVA part of the spectrum, with a broader range than humans. These results imply that the lux unit is inappropriate for describing the illuminance of a light source, as perceived by ducks and turkeys. The light environment in commercial duck and turkey housing was surveyed: mean illuminance was 22.6 and 5.3 lux, respectively. The spectral power distributions of the light sources and the birds' spectral sensitivity were used to estimate illuminance as perceived by ducks and turkeys; this varied by up to ~20% depending on light source. In a preference test ducklings and turkey poults were given a free choice between illuminances of < 1, 6, 20 and 200 lux at two and six weeks of age. Ducklings spent least time in < 1 lux though this was not affected by age. Turkey poults showed an overall preference for 200 lux at two weeks and 2:20 lux at six weeks. For both species, illuminance significantly affected the partition ofbehaviours. These results show that domestic ducks and turkeys have good colour vision, including UVA perception, and have distinct illuminance preferences. They imply that full spectrum lighting of varying temporal or spatial illuminance in housing might benefit welfare and satisfy preferences. Future work is needed to assess the use of UVA radiation by poultry and the strength of their motivation for illuminance.
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Jöbsis, Paul D. "Muscle oxygenation and blood flow during submersion in ducks (anas platyrhynchos) and seals (phoca vitulina) /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9907822.
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Águas, Maria Serpa Cabral de Matos. "Dispersão passiva de lagostim vermelho da Luisiana (Procambarus clarkii) através de pato-real (Anas platyrhynchos)." Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/15603.
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Neste trabalho testámos a possibilidade de dispersão passiva dos juvenis do lagostim vermelho da Luisiana (Procambarus clarkii) através de um vector animal, o pato-real (Anas platyrhynchos). Realizou-se uma experiência de dessecação, a duas temperaturas, constatando-se que os juvenis sobrevivem até 225 minutos fora de água, resistindo mais tempo quando à temperatura inferior. Realizaram-se também outras duas experiências para determinar a capacidade de se agarrarem a patas do pato e à plumagem do pato em movimento. Os resultados da primeira experiência levaram-nos a concluir que o tempo de repouso das patas afecta a probabilidade de transporte. Na segunda experiência concluímos que os juvenis se podem agarrar a um pato em movimento e que a probabilidade é afectada significativamente pela profundidade da água. Para determinar probabilidade de morte fora de água num vector animal, recrearam-se condições semelhantes às do voo de patos e obtiveram-se valores de LT50 e LT90 de 2,239 e 4,880 minutos, respectivamente; ABSTRACT:In this paper we investigated the possibility of passive dispersal of juvenile red swamp crayfish (Procambarus clarkii) through an animal vector, the mallard (Anas platyrhynchos). We performed a desiccation survival experiment, at two different temperatures and the results showed that the juveniles can survive until 225 minutes, and they resist longer at lower temperatures. We also performed other experiments to test the capacity to attach to duck´s legs and feathers while moving. The results of the first experiment show that the probability of transport is affected by the resting time. In the second experiment we concluded that the juveniles are able to attach to a moving duck and that the probability is significantly affected by water depth. To determine the survival time out of water on an animal vector, we recreated similar conditions similar to the duck’s flight and obtained LT50 and LT90 values of 2,239 and 4,880 minutes, respectively.
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Shimizu, Manabu. "Acid-base balance in arterial plasma of white Pekin duck (Anas platyrhynchos) during forced submergence and recovery." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25044.
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Acid-base balance in plasma was studied in forcibly submerged Pekin ducks (Anas platyrhynchos). All important variables determining acid-base balance (arterial CO₂ tension (PαCO₂) strong ion difference ([SID]) and total protein content which approximates total weak acid concentration in plasma) were measured.
During forced submergence PαCO₂ increased and pHa steadily decreased with time. There was also an increase in [lactate⁻], which was accompanied by an increase of equal magnitude in [Na⁺]. There were no significant changes in the concentrations of other strong ions (K⁺, Ca²⁺, Mg²⁺ and Cl⁻). Strong ion difference did not change during the first two minutes of submergence, but there was about a 4 mequiv/L increase by the end of the four-minute dive. Theoretically an increase in [SID] should cause plasma to be alkaline, but since plasma became progressively acidic, this condition can only be due to the increase in PαCO₂.
During recovery from dives, the plasma remained as acidic one minute after emersion as at the end of the dives. On the other hand, arterial pH slowly increased towards the pre-dive level during recovery. Arterial CO₂ tension decreased much more rapidly and was already at or below the pre-dive level one minute after emersion. Therefore, PαCO₂ could no longer affect plasma pH. There was, however, a great increase in [lactate-] in the first minute of recovery. Although [Na⁺] and [K⁺] were elevated, from pre-dive values after the four minute dive, the increase in [lactate⁻] resulted in a marked reduction in [SID]. Since there was no change in the total plasma protein content, the acidic condition observed in recovery could only be due to decreased [SID]. Breathing 0₂ before diving prevented circulatory adjustments and pH returned to pre-dive levels one minute after emersion, confirming that the acidic condition observed in recovery is a consequence of the lactate produced in the hypoperfused tissues during submergence.<br>Science, Faculty of<br>Zoology, Department of<br>Graduate
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Mahdi, Adnan Hammad. "The structure and innervation of the sphincters in the large intestine of the domestic duck (Anas platyrhynchos)." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/29864.
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Duckart, Susanne. "Untersuchungen zu Auswirkungen des Merkmals "Federhaube" auf die Embryogenese und Juvenilentwicklung bei Hausenten (Anas platyrhynchos f. dom.)." Giessen VVB Laufersweiler, 2007. http://d-nb.info/989809307/04.
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Gloutney, Mark Louis. "Nest-site selection, energetics of reproduction and comparative behaviour of mallard (Anas platyrhynchos) and blue-winged teal (A. discors)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24058.pdf.
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Oellrich, Wiebke. "Experimentelle Untersuchungen zum Verlauf von Infektionen mit Salmonella Enteritidis und Salmonella Typhimurium bei der kommerziell genutzten Pekingente (Anas platyrhynchos)." Giessen DVG-Service, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?idn=980872472.
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Rodrigue, Jean. "Utilisation du canard de Pékin (Anas platyrhynchos) comme bioindicateur de la contamination du milieu naturel par les substances bioaccumulables." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22796.
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Eighteen-month-old adult female Peking Ducks (Anas platyrhynchos) were placed in the Ottawa, and St. Lawrence rivers for periods varying between 14 and 72 days during the summers of 1987, 1988 and 1989. Two stations located on Lake St. Francis were selected for establishing a time-curve for the accumulation of organochlorine pesticides (OC) and PCB in the liver. The ducks rapidly lost weight during their first 20 days in the natural environment but stabilised after about 40 days. This weight loss was caused by the stress of habitat, change, the energetic costs in searching for food and moulting.<br>There was a rapid increase in the number and concentration of contaminants detected in the livers of ducks exposed to pollutants in the natural environment. The concentrations found were low (99.9% of OC-PCB are under 1 mg/kg wet weight basis). These individuals were generally from 10 to 1000 times more contaminated than the control ducks for 40 days of exposure.<br>The use of domestic ducks as bioindicators has several advantages. They can be obtained readily and cheaply, and the sex and age of the individuals can be controlled. Since they are not very mobile and therefore are easy to locate, they provide information on the contamination (metals or OC-PCB) of specific sites. The use of Peking ducks has some limitations. There is a need for appropriate habitats to ensure their survival, and there is considerable stress caused by transferring the ducks from the breeding farm to the natural environment, thereby obliging them to search for food and exposing them to predators and poachers. (Abstract shortened by UMI.)
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Lauterbach, Sarah E. "Year-round influenza A virus surveillance in mallards (Anas platyrhynchos) reveals genetic persistence during the under-sampled spring season." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1586522647739509.
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Nishizawa, Márcia [UNESP]. "Estudo dos estados imune e de portador em marrecos de pequim (Anas platyrhynchos) frente ao vírus da doença de Newcastle." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/104635.
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nishizawa_m_dr_jabo.pdf: 817217 bytes, checksum: c7d2f29bf8d4ac1ee5c3fbc71c4756c1 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Parâmetros imunológicos, clínicos, epidemiológicos e patológicos da vacinação em marrecos de Pequim foram avaliados por 3 experimentos. Para tanto, foram utilizadas amostras vacinais Ulster 2C, B1 e LaSota do vírus da doença de Newcastle (VDN). No experimento 1, foram utilizados 120 marrecos de Pequim de 1 dia de idade, distribuídos em 4 tratamentos de 30 animais cada, submetidos a diferentes programas imunoprofiláticos. A resposta imune foi avaliada pelo teste de HI, com posterior desafio frente a estirpe patogênica do VDN, aos 60 dias de vida das aves. Após o desafio, em todos os grupos, procedeu-se o reisolamento de vírus patogênico em embriões SPF. Independente do grupo experimental, sinais clínicos da reação vacinal não foram observados. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Os marrecos de Pequim desafiados mostraram-se refratários à enfermidade clínica com o VDN. Entretanto, ficou caracterizado o estado de portador de VDN nesta espécie decorridos até 30 dias da infecção experimental com este patógeno. Nos grupos vacinados, o reisolamento de vírus patogênico foi nulo, evidenciando -se assim a importância da imunoprofilaxia na supressão do estado de portador de VDN dos marrecos de Pequim. No experimento 2, aves SPF foram colocadas em contato íntimo com marrecos de Pequim inoculados com uma estirpe patogênica do VDN, decorridos cinco e 14 dias...<br>The clinical, epidemiological, immunological and pathological parameters of vaccination in white Pekin ducks were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the Newcastle disease virus (NDV) were used. In experiment 1, 120 one-day-old white Pekin ducks were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for re-isolation of the virus in SPF embrionated eggs. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged white Pekin ducks were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 30 days after experimental infection. The vaccinated groups of white Pekin ducks did not present any virus in the re-isolation of the pathogenic virus. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the white Pekin ducks. In experiment 2, SPF chickens housed with white Pekin ducks which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days...(Complete abstract, acess undermentioned eletronic address)
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Duranel, Arnaud. "Effets de l'ingestion de plombs de chasse sur le comportement alimentaire et la condition corporelle du canard colvert (Anas platyrhynchos)." Phd thesis, Ecole nationale vétérinaire de Nantes, 1999. http://tel.archives-ouvertes.fr/tel-00825999.
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Après avoir fait la synthèse des connaissances sur le saturnisme chez les Anatidés et rappelé l'importance de la compétitivité, notamment en terme de recherche alimentaire et de condition corporelle, pour la survie et le succès reproducteur d'un individu en milieu naturel, l'auteur décrit les effets de l'ingestion d'un faible nombre de plombs de chasse chez le Canard colvert. Il montre que la vitesse d'ingestion de l'aliment est corrélée de façon négative à la plombémie jusqu'à quatre semaines au minimum après ingestion des plombs. A ce stade, la condition corporelle, estimée par un index d'adiposité et un index musculaire, est inversement proportionnelle à plusieurs paramètres toxicologiques témoins de l'intoxication par le plomb (protoporphyrinémie, hématocrite, concentration en plomb dans les tissus). De même, il existe une corrélation entre plusieurs de ces paramètres et la perte de poids maximum relevée au cours de l'évolution de l'intoxication. On peut donc penser que l'ingestion d'un faible nombre de plombs de chasse, à l'origine d'une intoxication sublétale, voire subclinique, a un effet négatif sur l'acquisition et le stockage des réserves énergétiques chez les Anatidés. D'autre part, une régression logistique montre que la protoporphyrinémie deux semaines après l'ingestion des plombs décrit très bien la probabilité de survie des canards. Ainsi, la comparaison des corrélations entre symptômes et indicateurs toxicologiques propose que, dans les conditions de l'expérimentation, la protoporphyrinémie serait mieux adaptée que la plombémie pour dépister le saturnisme.
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Nishizawa, Márcia. "Estudo dos estados imune e de portador em marrecos de pequim (Anas platyrhynchos) frente ao vírus da doença de Newcastle /." Jaboticabal : [s.n.], 2007. http://hdl.handle.net/11449/104635.
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Orientador: Antonio Carlos Paulillo<br>Banca: Ruben Pablo Schoken-Iturrino<br>Banca: Laura Satiko Okada Nakaghi<br>Banca: Luciano Doretto Júnior<br>Banca: Maria Estela Gaglianone Moro<br>Resumo: Parâmetros imunológicos, clínicos, epidemiológicos e patológicos da vacinação em marrecos de Pequim foram avaliados por 3 experimentos. Para tanto, foram utilizadas amostras vacinais Ulster 2C, B1 e LaSota do vírus da doença de Newcastle (VDN). No experimento 1, foram utilizados 120 marrecos de Pequim de 1 dia de idade, distribuídos em 4 tratamentos de 30 animais cada, submetidos a diferentes programas imunoprofiláticos. A resposta imune foi avaliada pelo teste de HI, com posterior desafio frente a estirpe patogênica do VDN, aos 60 dias de vida das aves. Após o desafio, em todos os grupos, procedeu-se o reisolamento de vírus patogênico em embriões SPF. Independente do grupo experimental, sinais clínicos da reação vacinal não foram observados. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Os marrecos de Pequim desafiados mostraram-se refratários à enfermidade clínica com o VDN. Entretanto, ficou caracterizado o estado de portador de VDN nesta espécie decorridos até 30 dias da infecção experimental com este patógeno. Nos grupos vacinados, o reisolamento de vírus patogênico foi nulo, evidenciando -se assim a importância da imunoprofilaxia na supressão do estado de portador de VDN dos marrecos de Pequim. No experimento 2, aves SPF foram colocadas em contato íntimo com marrecos de Pequim inoculados com uma estirpe patogênica do VDN, decorridos cinco e 14 dias...(Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The clinical, epidemiological, immunological and pathological parameters of vaccination in white Pekin ducks were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the Newcastle disease virus (NDV) were used. In experiment 1, 120 one-day-old white Pekin ducks were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for re-isolation of the virus in SPF embrionated eggs. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged white Pekin ducks were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 30 days after experimental infection. The vaccinated groups of white Pekin ducks did not present any virus in the re-isolation of the pathogenic virus. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the white Pekin ducks. In experiment 2, SPF chickens housed with white Pekin ducks which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days...(Complete abstract, acess undermentioned eletronic address)<br>Doutor
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Sell, Cameron W., University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "An investigation into the Australian duck industry with particular reference to the energy and amino acid requirements of commercially farmed Australian pekin ducks (Anas Platyrhynchos)." THESIS_CSTE_EAG_Sell_C.xml, 2003. http://handle.uws.edu.au:8081/1959.7/522.
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Limited published data exists on the Australian duck industry, particularly in relation to the nutritional requirements of the commercial duck (Anas Platyrhynchos). A series of seven experiments was designed to determine whether current nutritional recommendations for energy, lysine, methionine, threonine and tryptophan were sufficient to optimise growth, feed efficiency, and carcass characteristics of the duck. The ability of the duck to perform diet self selection was then examined for its potential use in the Australian industry. The outcome of the diet self selection experiments showed that ducks sometimes self select diets when offered choices from four diets differing in nutrient density. A key outcome of this research was the development of a revised set of nutrient specifications designed to maximise the performance of the Australian commercially grown duck. These proposed specifications could be economically beneficial to the expanding Australian duck industry<br>Doctor of Philosophy (PhD)
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Ribeiro, Ana Pires Fernandes. "Perfil nutricional da fracção lipídica da carne de aves cinegéticas (perdiz, faisão, pato)." Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2013. http://hdl.handle.net/10400.5/5969.
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Dissertação de Mestrado em Segurança Alimentar<br>As aves cinegéticas suscitam um grande interesse nos caçadores, no entanto a qualidade da carne não tem tido esse impacto ao nível da comunidade científica. Assim, o objectivo deste estudo foi caracterizar a fracção lipídica da carne (peito e perna) de faisão, pato e perdiz, de produção (Phasanius colchius, Anas platyrhynchos, Alectoris rufa) assim como comparar a fracção lipídica da carne de perdizes de produção e silváticas.
Os lípidos totais foram determinados gravimetricamente, o colesterol total e os tococromanóis foram quantificados por HPLC acoplado a detectores de díodos e de fluorescência, enquanto os ácidos gordos foram determinados por GC-FID.
Os resultados obtidos revelaram uma alta variabilidade para quase todos os ácidos gordos, somatórios parciais e rácios em ambas as porções (peito e perna). O pato foi a espécie com um maior teor de lípidos totais em ambas as porções. O teor de colesterol mais elevado foi encontrado no peito do pato e na perna da perdiz (56,3 e 55,1 mg/100 g de carne).
Um total de 5 tococromanóis da vitamina E foi detectado em todas as espécies, mas em concentração variável. O perfil de ácidos gordos de todas as espécies de produção e da perdiz selvagem foi dominado por SFA e MUFA. Nenhuma das espécies no estudo apresenta uma total concordância com as recomendações internacionais para os rácios P/S e n-6/n-3.<br>ABSTRACT - Game birds represent an important issue to the hunter´s community, however their meat quality has not been valued by the scientific community. Therefore, the objective of this study was to characterize the lipid fraction of meat (breast and leg) from farmed pheasant, mallard and partridge (Phasanius colchius, Anas platyrhynchos, Alectoris rufa) as well as compare the meat lipid fraction of wild and farmed partridge.
For this study we used 14 birds of each specie equally divided by both genders. Total lipids were measured gravimetrically, total cholesterol and tocochromanols were quantified by HPLC coupled with a DAD and Fluorescence detectors, while fatty acid profile was measured by GC-FID.
The study results revealed a high variability for almost all single fatty acids, fatty acid sums and ratios in both portions (breast and leg). Mallard was the specie with the highest total lipid content for both portions. The highest total cholesterol content was found in mallard breast and partridge leg (56,3 and 55,1 mg/100 g of meat). A total of 5 tocochromanols with vitamin E activity were detected in all species, but in a variable concentration. The fatty acid profile of all farmed species and wild partridge was dominated by SFA and MUFA. None of bird species in study was in full agreement with international recommendations for P/S and n-6/n-3 ratios.
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Oellrich, Wiebke [Verfasser]. "Experimentelle Untersuchungen zum Verlauf von Infektionen mit Salmonella Enteritidis und Salmonella Typhimurium bei der kommerziell genutzten Pekingente (Anas platyrhynchos) / vorgelegt von Wiebke Oellrich." Gießen : DVG-Service, 2006. http://d-nb.info/980872472/34.
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Varna, Klaidas. "Pienarūgščių bakterijų paieška ir jų identifikavimas migruojančių didžiųjų ančių (Anas platyrhynchos) žarnyne naudojant dalinių 16S rRNR geno sekų analizę ir kultivavimu paremtus metodus." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20090908_194033-88862.
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Pienarūgščių bakterijų paieška ir jų identifikavimas migruojančių didžiųjų ančių (Anas platyrhynchos) žarnyne naudojant dalinių 16S rRNR geno sekų analizę ir kultivavimu paremtus metodus Klaidas VARNA Vilniaus Universiteto Ekologijos Institutas, Hidrobiontų Ekologijos ir Fiziologijos Laboratorija bei Populiacinės Genetikos Laboratorija, Akademijos-2, Vilnius-21, 08412, Lietuva. Šiame tyrime pavasarinių ir rudeninių didžiųjų ančių (Anas platyrhynchos) migrantų iš Nemuno deltos virškinamojo trakto pieno rūgšties bakterijų įvairovė buvo ištirta naudojant molekulinius metodus (polimerazės grandininės reakcijos amplifikacija ir dalinių 16S rRNR geno sekų sekvenavimas) ir kultivavimu paremtus metodus. Migruojančių didžiųjų ančių (Anas platyrhynchos) pieno rūgšties bakterijų paieška buvo atlikta pirmą kartą. Rudeniniai didžiųjų ančių migrantai plonojo žarnyno sienelėse (1.2×107 iki 2.1×107 k.f.v./g) ir jų turinyje (nuo 3.4×107 iki 1.1×108 k.f.v./g) turi didesnį pieno rūgšties bakterijų skaičių nei pavasariniai migrantai (atitinkamai nuo 3.2×106 iki 4.8×106 k.f.v./g ir nuo 1.0×107 iki 2.2×107 k.f.v./g). Tiek rudeninių tiek ir pavasarinių didžiųjų ančių migrantų plonojo žarnyno sienelėse ir jų turinyje dominavo kokinės pieno rūgšties bakterijų formos (atitinkamai 65% ir 83.5% bei 81.4% ir 91.6%), o lazdelių buvo mažiau (atitinkamai 35% ir 16.5% bei 18.6% ir 8.4%). Manoma, kad minėtus skirtumus įtakoja keli veiksniai: ilgai trunkanti migracija, perėjimo periodas, skirtingas maistas ir... [toliau žr. visą tekstą]<br>Identification of lactic acid bacteria in the migrant mallard ducks Anas platyrhynchos intestinal tract by partial 16S rRNA gene sequence analysis and using culture-based techniques Klaidas VARNA Institute of Ecology of Vilnius University, Laboratory of Hydrobionts Ecology and Physiology, Laboratory of Population Genetics, Akademijos-2, Vilnius-21, 08412, Lithuania. In this study the lactic acid bacteria diversity of the intestinal tract content of the vernal and autumnal migrant mallard ducks (Anas platyrhynchos) from Nemuno delta has been investigated by molecular methods: polymerase chain reaction amplification and sequencing of partial 16S rRNA genes and using culture-based techniques. The investigation of the lactic acid bacteria of the migrant mallard ducks has been performed the first time. Autumnal migrant mallard ducks in the small intestine walls (from 1.2×107 until 2.1×107 c.f.u./g) and in their content (from 3.4×107 until 1.1×108 c.f.u./g have the greatest number of the lactic acid bacteria then vernal migrants (respectively from 3.2×106 until 4.8×106 c.f.u./g and from 1.0×107 until 2.2×107 c.f.u./g). In the small intestine walls and in their content of the autumnal and vernal migrant mallard ducks, dominated cocci-shaped lactic acid bacteria (respectively 65% and 83.5%, 81.4% and 91.6%), whereas rod-shaped was under (respectively 35% and 16.5%, 18.6% and 8.4%). Supposedly, that these defferences determine some factors: a long migration, period of incubate... [to full text]
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Sell, Cameron W. "An investigation into the Australian duck industry with particular reference to the energy and amino acid requirements of commercially farmed Australian pekin ducks (Anas Platyrhynchos)." Thesis, View thesis, 2003. http://handle.uws.edu.au:8081/1959.7/522.
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Limited published data exists on the Australian duck industry, particularly in relation to the nutritional requirements of the commercial duck (Anas Platyrhynchos). A series of seven experiments was designed to determine whether current nutritional recommendations for energy, lysine, methionine, threonine and tryptophan were sufficient to optimise growth, feed efficiency, and carcass characteristics of the duck. The ability of the duck to perform diet self selection was then examined for its potential use in the Australian industry. The outcome of the diet self selection experiments showed that ducks sometimes self select diets when offered choices from four diets differing in nutrient density. A key outcome of this research was the development of a revised set of nutrient specifications designed to maximise the performance of the Australian commercially grown duck. These proposed specifications could be economically beneficial to the expanding Australian duck industry
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Sell, Cameron W. "An investigation into the Australian duck industry with particular reference to the energy and amino acid requirements of commercially farmed Australian pekin ducks (Anas Platyrhynchos) /." View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20051007.105841/index.html.
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Chauve, Claude. "Caractérisation de la faune coccidienne des Anatinae domestiques : Anas platyrhynchos, Cairina moschata, et leur hybride, le canard mulard : description d'une nouvelle espèce, Eimeria mulardi Chauve et al., 1994 : cycle évolutif et pathogénicité." Lyon 1, 1994. http://www.theses.fr/1994LYO1T096.
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McKean, Josephine Kay. "Effects of alcohol on the development of the cardiovascular system in Pekin Ducks (Anasplatyrhynchos): An assessment of current empirical findings and the development of aresearch protocol utilizing Pekin Ducks." Capital University Honors Theses / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=caphonors1619709990242982.
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Lanchon-Aubrais, Elisabeth. "Conséquences d'un apport artificiel de nourriture sur le comportement d'un canard de surface : le canard colvert (anas platyrhynchos, l.) et d'un canard plongeur: le fuligule milouin (aythya ferina, l.) au lac de grand-lieu." Rennes 1, 1992. http://www.theses.fr/1992REN10160.
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Au lac de Grand-Lieu, la pratique de la chasse au gibier d'eau amène la distribution quotidienne de 1 a 5 tonnes de blé. Quelques minutes après l'agrainage effectué le matin en eau superficielle, les colverts rejoignent en masse les sites de nourrissage et s'alimentent intensément. 1 a 2 h après, ils rejoignent des aires de repos propres a chaque site. En revanche, les milouins, agrainés en eau plus profonde, stationnent toute la journée sur les postes de nourrissage ou alternent des phases alimentaires et de confort. En été, les colverts quittent le lac le soir pour rejoindre des gagnages naturels. Ces mouvements diminuent considérablement des l'ouverture de la chasse et deviennent pratiquement nuls en automne, époque a laquelle colverts et milouins profitent de l'accessibilité des ressources du lac bien que fréquentant aussi les agrainages pendant la nuit. La montée des eaux en début d'hiver et l'arrêt de l'agrainage à faible profondeur entraînent à nouveau l'utilisation de gagnages nocturnes externes au lac. Le blé domine dans le régime alimentaire des deux espèces (98 et 99% du poids sec du contenu des jabots) malgré l'abondance des graines naturelles et en particulier de scirpus lacustris qui semble servir essentiellement de grit
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BOOS, MATHIEU. "Modifications des reserves energetiques corporelles du canard colvert (anas platyrhynchos) et de la becasse des bois (scolopax rusticola) au cours de leur hivernage : aspects fonctionnels lies a la biologie de ces especes et aux conditions du milieu." Université Louis Pasteur (Strasbourg) (1971-2008), 2000. http://www.theses.fr/2000STR13089.
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L'hivernage est une periode critique pour de nombreuses especes d'oiseaux, notamment parce que la balance energetique peut subitement devenir negative en raison de vagues de froid ou d'une intoxication par des metaux lourds. Ce travail a ainsi ete realise sur le canard colvert et la becasse des bois, especes ayant une sensibilite hivernale differente. Chez le canard colvert, espece a fort dimorphisme sexuel, les femelles accumulent, relativement a leur masse corporelle, une plus grande quantite de lipides que les males ; ces derniers ont en outre une charge alaire plus elevee. Chez la becasse des bois, la composition corporelle differe peu entre les sexes, neanmoins chez cette espece, les muscles locomoteurs sont relativement plus developpes que chez le colvert, ce qui confererait a la becasse un avantage en terme de capacites thermogeniques. Les modeles mathematiques d'estimation des masses de lipides et de proteines corporels, alternatifs a des methodes biochimiques classiques, longues et fastidieuses, montrent que pour les deux especes, la masse corporelle constitue l'indice lipidique et proteique le plus fiable et le plus simple a appliquer chez des animaux vivants. Seul pour les lipides, la precision d'estimation est augmentee en considerant la masse du tissu adipeux abdominal et de la masse corporelle seche. L'etude des relations entre conditions climatiques et etat des reserves energetiques montre que, chez le colvert hivernant sur le rhin, a l'inverse des becasses, les vagues de froid intenses n'entrainent pas de depletion letale des reserves energetiques : le caractere opportuniste et l'acces a certaines parties non gelees du quartier d'hiver expliquerait cette faible sensibilite. Cependant, chez le colvert, une intoxication au plomb peut induire un catabolisme accelere des reserves energetiques et ainsi affecter la survie plus serieusement que des vagues de froid prolongees. Globalement, cette etude pourra contribuer a l'amenagement des quartiers d'hiver.
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García, Suikkanen Carolina. "Estudio de los efectos de las infraestructuras de transporte sobre la fauna en un humedal costero mediterráneo (Parque Natural de l'Albufera de Valencia). Propuesta de medidas para la desfragmentación y valoración de sus efectos sobre dos especies representativas: ánade azulón (Anas platyrhynchos) y gineta (Genetta genetta)." Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/14636.
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El estudio se centra en dos de los efectos más importantes que ejerce la presencia de las infraestructuras lineales sobre la fauna: los atropellos y el efecto barrera. El área de estudio corresponde un humedal costero protegido, el Parque Natural de l'Albufera. Para el estudio de los atropellos se prospectaron las carreteras que recorren el interior de dicho Parque en bicicleta, registrando los atropellos de vertebrados detectados. Mediante este estudio se pudo comprobar el gran impacto que supone la presencia de estas vías sobre la fauna presente en el entorno. Uno de los grupos faunísticos más afectados corresponde al grupo de las aves, entre las cuales destacaba el ánade azulón. Dada su importancia se desarrolló un estudio en profundidad de las condiciones que determinan la elevada mortalidad de esta especie. Así se comprobó como los atropellos se producen cuando las familias atraviesan la carretera CV-500 desde la Devesa, una zona forestal empleada para la nidificación, hacia los arrozales del marjal, zona que emplean para la alimentación de los pollos. Este fenómeno se repite todos los años, con una elevada concentración temporal (mayoritariamente durante el mes de junio) y espacial (en el tramo de CV-500 que bordea la Devesa del Saler).
Otra de las especies que se ve afectada por la presencia de estas vías de transporte corresponde a la gineta. Este carnívoro de medio tamaño se dio por extinto en el Parque en los años 70. Para estudiar la población de gineta se emplearon diversas metodología que incluían el estudios de radio tracking, seguimiento de letrinas y trampeo fotográfico. Mediante estas técnicas se ha podido comprobar la presencia de una población estable de gineta en la zona forestal de la Devesa. Sin embargo, los resultados obtenidos indican que el tamaño poblacional debe ser muy reducido, por lo que el impacto de los atropellos se considera un problema muy grave.<br>García Suikkanen, C. (2011). Estudio de los efectos de las infraestructuras de transporte sobre la fauna en un humedal costero mediterráneo (Parque Natural de l'Albufera de Valencia). Propuesta de medidas para la desfragmentación y valoración de sus efectos sobre dos especies representativas: ánade azulón (Anas platyrhynchos) y gineta (Genetta genetta) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14636<br>Palancia
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Mahoney, Michael Jeffrey. "Brood preferences in brooding mallard hens (Anas platyrhynchos platyrhynchos)." 1986. http://hdl.handle.net/1993/9344.
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Javůrková, Veronika. "Antipredační strategie kachny divoké (Anas platyrhynchos)." Master's thesis, 2007. http://www.nusl.cz/ntk/nusl-370371.
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Beaudoin, Laura A. "Examining the components of attachment in mallard ducklings (Anas platyrhynchos platyrhynchos)." 2006. http://hdl.handle.net/1993/20317.
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Wereha, Tyler J. "Brood size preferences of broods of mallard ducklings (Anas platyrhynchos platyrhynchos)." 2007. http://hdl.handle.net/1993/21026.
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Lin, Wei-Chih, and 林偉智. "Morphogenesis of the curly tail feathers in mallard (Anas platyrhynchos)." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/26525471235291267732.
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碩士<br>國立中興大學<br>動物科學系所<br>105<br>Mallard (Anas platyrhynchos) is a common meat-type water fowl. During their breeding seasons (April to May and September to October in Taiwan), the mallard show sexual dimorphic plumage. However, four tail feathers, called sexual curled feathers (SCFs), surrounding the oiler gland in the male mallard display curly morphology, which is different from the rest of tail feathers. Furthermore, the curly-shape feathers exist irrelevantly to the breeding seasons and are absent in the female. Therefore, the aims of this study were to investigate the coordination of changes of serum sex hormone levels and morphogenesis of SCFs during growth, and to study the possible molecular regulation on the morphogenesis of SCFs. In Experiment I, the duck blood samples were collected every two weeks. ELISA kits (Cayman Chemical) were applied to analyze the level of testosterone (T) and estradiol (E2) in mallard serum. Also, the molting phenomenon was recorded during the period of time. Increasing E2 level was noticed in the female before sexual maturity and it reached to the peak after maturity. It was shown that an obviously increased level of T appeared prior to sexual maturity in the male mallard, and at this time point, the SCFs appeared in the male. Interestingly, T peak was found to be associated with molting, i.e. T peak appears before pre-nuptial and post-nuptial molting. Furthermore, it was found that in addition to a T peak, an E2 peak was shown prior to post-nuptial molting. The level of E2 significantly increased before laying period, but no significant difference of E2 level was found between molting in the female mallard, indicating E2 level related to laying only. In Experiment II, two weeks (called early regenerating stage) and four weeks (called late regenerating stage) after plucking SCFs and not curly tail feather (called none sexual curly feathers, nonSCFs) from the male and female mallards, the growing feather follicles were collected and three tissues, including dermal papillae (DP), outside epithelium (O-epi) and pulp (pp), were dissected out for total RNA extraction to analyze the expression of androgen receptor (AR), estrogen receptor α/β (ERα/β), bone morphogenetic protein 2/4 (BMP2/4) and aromatase cytochrome P450 (CYP19) by RT-PCR (reverse transcription-polymerase chain reaction). The result showed that there is no significant difference between SCFs and nonSCFs in the expression of ERα/β, BMP2/4 and CYP19 in all samples. However, AR was found to express in all tissues in SCFs at early and late stages, while it was only expressed in DP in nonSCFs at both stages. The AR expression pattern was consistent with the RNA in situ hybridization results. In Experiment III, no expression of keratin75 (KRT75) was detected in SCFs and nonSCFs in both male and female mallard by immunohistochemistry analysis. However, keratin17 (KRT17) was found to express around barb ridge. The rachis of SCFs from the male mallard showed cell apoptosis by TUNEL assay. In conclusion, the results present in this study have demonstrated that the changes of sex hormone level may be involved in the trigger of breeding, molting and feather morphogenesis. Furthermore, AR, to certain extent, plays an important role on the formation of SCFs. Further studies are required to elucidate the molecular regulation of AR and other molecules on feather morphogenesis.
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"Ciclo reprodutivo anual e caracteristicas morfologicas testiculares do pato domestico (Anas platyrhynchos)." Tese, Biblioteca Digital da Unicamp, 2004. http://libdigi.unicamp.br/document/?code=vtls000336873.
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