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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.
71

Sinaliza??o crom?tica da condi??o reprodutiva de f?meas de segui comum (Callithrix jacchus) / Reproductive signaling in female common marmosets (Callithrix jacchus).

Moreira, La?s Alves Ant?nio 26 April 2013 (has links)
Made available in DSpace on 2014-12-17T15:37:17Z (GMT). No. of bitstreams: 1 LaisAAM_DISSERT.pdf: 1507276 bytes, checksum: 23b9ddf330fd173132cb924ee0fb4b51 (MD5) Previous issue date: 2013-04-26 / As social animals, primates use different sensory modalities (acoustic, chemical, tactile and visual) to convey information about social and sexual status to conspecifics. Among these modalities, visual signals are widely used, especially color signals, since primates are the mammalian group that displays the greatest variety of colors in their skin and fur. Studies with Old World primate species suggest that hormonal variations are related to variations in the colors of individual faces and genitals. Therefore, chromatic cues can be used by conspecifics to identify the reproductive condition of an individual. To date, studies with the same approach are unknown for New World species. However, behavioral and physiological studies suggest that different New World primate species seem to perceive reproductive conditions such as the timing of female conception and gestation. Thus, in this study, our aim was to: i) identify whether there are chromatic cues on the skin of female common marmosets, (Callithrix jacchus) that indicate their reproductive condition; ii) define whether this chromatic variation can be perceived by all visual phenotypes known in this species; iii) identify if these chromatic cues can be perceived under different light intensity levels (dim, intermediate and high). For this, we selected 13 female common marmosets in four distinct reproductive conditions: pregnant female preceding parturition, postpartum mothers, noncycling and cycling females. The coloration of the skin in genital and thigh areas in females was measured using a spectrophotometer. Using mathematical models of visual perception, we calculated the values of quantum catch for each photoreceptor type known in this species, the visual opponency channels and color contrast between those body spots. Our results indicate the occurance of chromatic variations in the genital area during the weeks that precede and follow parturition, forming a U-pattern of variation perceptible to males and females in natural conditions of low and high luminosity. Furthermore, we observed distinct color patterns in the genital skin of pregnant and cycling females that indicate their reproductive conditions. Finally, we present evidence of color contrast in noncycling females that is higher than that of pregnant ones. This study suggests that there is a chromatic xii variation in the genital skin of females that can be perceived by conspecifics and that may be related to hormonal changes typical of pregnancy and the ovarian cycle / Como animais sociais, os primatas usam sinais de diferentes modalidades (ac?stico, qu?mico, t?til e visual) para transmitir informa??es sobre status social e sexual a membros da mesma esp?cie. Dentre essas modalidades, os sinais visuais s?o amplamente utilizados, especialmente os sinais de cor, uma vez que dentre os mam?feros, os primatas formam o grupo com maior variedade de cores em suas peles e pelos. Trabalhos com esp?cies de primatas do Velho Mundo sugerem que varia??es hormonais estejam relacionadas com varia??es crom?ticas vis?veis em ?reas genitais e faces de machos e f?meas. Desta forma, pistas crom?ticas podem ser usadas por coespec?ficos para identificar a condi??o reprodutiva de um indiv?duo. At? o momento, trabalhos com essa mesma abordagem em esp?cies do Novo Mundo s?o desconhecidos. Por?m, estudos comportamentais e fisiol?gicos sugerem que diferentes esp?cies de primatas do Novo Mundo parecem perceber caracter?sticas reprodutivas como o momento da concep??o e a fase da gesta??o em f?meas. Desta forma, neste trabalho buscamos: i) identificar se existem pistas crom?ticas na pele de f?meas de sagui comum (Callithrix jacchus) que indicam a condi??o reprodutiva; ii) determinar se essas pistas s?o percept?veis aos diferentes fen?tipos visuais encontrados na esp?cie; iii) identificar qual seria o efeito de diferentes condi??es de ilumina??o na detec??o dessa colora??o. Para isso, trabalhamos com 13 f?meas de sagui comum em quatro condi??es reprodutivas distintas: gestantes pr?-parto, gestantes p?s-parto, ovulat?rias e n?o ovulat?rias. A colora??o de ?reas da pele das f?meas foi mensurada utilizando um espectrofot?metro e, utilizando modelos matem?ticos de percep??o visual, calculamos os valores de capta??o qu?ntica para cada tipo de fotorreceptor presente na esp?cie, os canais de opon?ncia visual e o contraste crom?tico entre duas ?reas corp?reas. Esse trabalho mostra evid?ncias de varia??o no contraste crom?tico das peles da genit?lia e da coxa nas semanas que antecedem e sucedem o parto, formando um padr?o de varia??o em U percept?vel a machos e f?meas em condi??es naturais de baixa e alta luminosidade. Al?m disso, evidenciamos padr?es de colora??o distintos na regi?o da pele genital para f?meas gestantes que indicam uma sinaliza??o dessa condi??o reprodutiva. Por fim, apresentamos evid?ncias de que o contraste de cor em f?meas x ovulat?rias e n?o ovulat?rias ? superior ao de f?meas gestantes. Este estudo sugere que existe uma varia??o crom?tica na pele genital de f?meas, que essa varia??o ? percept?vel a coespec?ficos e que pode estar relacionada ?s altera??es hormonais acentuadas que ocorrem durante a gesta??o e o ciclo ovariano
72

Ecologia e comportamento de Callitrichidae (Primates) no Jardim Botânico do Rio de Janeiro / Ecology and behavior of Callitrichidae (Primates) in Rio de Janeiro Botanic Garden

Cristiane Hollanda Rangel 25 February 2012 (has links)
Espécies exóticas são consideradas a segunda maior ameaça ao meio ambiente, sendo um risco às espécies nativas devido à predação, competição, hibridação e transmissão de patógenos. Callithrix jacchus e Callithrix penicillata são espécies exóticas amplamente difundidas no Estado do Rio de Janeiro. No presente estudo, dados comportamentais e ecológicos foram amostrados entre Setembro de 2008 e Agosto de 2009 usando-se o método animal focal com amostragem instantânea, acompanhando sete grupos mistos de Callithrix spp. no arboreto do Jardim Botânico do Rio de Janeiro (JBRJ). A densidade dos saguis foi estimada em cerca de 130 indivíduos por Km2. Na dieta, foram identificadas 51 espécies arbóreas fontes de exsudatos e 39 espécies fontes de frutos, folhas, flores e néctar. Os saguis se alimentaram também de invertebrados, pequenos vertebrados, e alimentos direta ou indiretamente fornecidos por visitantes do JBRJ. O consumo de exsudatos foi maior na estação mais seca, e de frutos e insetos na estação mais chuvosa. Os saguis utilizaram mais os estratos verticais intermediários e sub-bosque nas suas atividades diárias, e áreas protegidas por epífitas no dossel de 30 espécies diferentes de árvores como locais de dormida. Os saguis apresentaram relações interespecíficas harmônicas, neutras e desarmônicas com diversas espécies de aves e mamíferos. A dispersão de sementes de árvores exóticas e o uso exagerado de espécimes vegetais para gomivoria pelos saguis podem afetar a integridade da coleção do JBRJ. A alta densidade de saguis e predação de espécies da fauna local podem afetar o equilíbrio da comunidade faunística. Com base nas observações in situ, as espécies alóctones C. jacchus e C. penicillata causam danos e necessitam de manejo, que deve ser estudado e implementado para o controle criterioso de suas populações. / Exotic species are considered the second biggest threat to the environment, representing a risk to native species due to predation, competition, hybridization and disease transmission. Callithrix jacchus and C. penicillata are exotic species widely spread out in the Rio de Janeiro State. For this study, behavioural and ecological data were sampled between September 2008 and August 2009 through the use of focal animal method with instantaneous sampling, following seven mixed groups of Callithrix spp. in the Arboretum of Rio de Janeiro Botanic Garden (JBRJ), Rio de Janeiro. The marmoset density was estimated on 130 individuals per km2. We identified 51 tree species as exudate sources, 39 species as sources of fruits, leaves, flowers and nectar. The marmosets can also eat invertebrates, small vertebrates, and food offered by visitors of JBRJ. The consumption of exudates was concentrated in the dry season, and fruit and insects in the rainy season. The marmosets used most intermediate strata and understory in their daily activities, and areas protected by epiphytes in the canopy of 30 different species of trees as sleeping sites. The marmosets showed interspecific relationships as harmonic, neutral and disharmonious with several species of birds and mammals. The diffusion of exotic tree seeds and the overuse of plant specimens for gummivory of marmosets can affect the integrity of the JBRJ collection. The high density of marmosets and predation of native fauna can affect the integrity of the fauna. Considering the potential and observed damage caused by exotic species Callithrix jacchus and C. penicillata, management measures should be studied and implemented to control their populations.
73

Comportamento e utilização do habitat em grupos de Callithrix sp. (Primates, Callithrichidae) no Instituto de Pesquisas do Jardim Botânico do Rio de Janeiro / Behavior and habitat use in groups of Callithrix sp. (Primates, Callithrichidae) at the Research Institute of the Botanical Garden of Rio de Janeiro

Marina Trancoso Zaluar 21 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As populações introduzidas de saguis preocupam biólogos e conservacionistas, por causa do seu potencial de ocupação de hábitat, hibridação com congêneres nativos, predação de representantes da fauna local, transmissão de doenças e competição com outras espécies. É necessário entendermos o que favorece essa flexibilidade na utilização do suporte e no padrão comportamental que possibilita que os saguis sobrevivam em ambientes florestais tão diversos e até mesmo em regiões muito alteradas e antropizadas, como as grandes metrópoles. Foram acompanhados indivíduos de Callithrix sp. no arboreto do JBRJ. O trabalho de campo foi feito entre agosto de 2012 e agosto de 2013 e acumulou 205 horas de observações e 400 horas de esforço amostral. O método de amostragem utilizado foi o Animal Focal, no qual apenas um indivíduo do grupo foi analisado por sessão amostral, de 3 minutos com 7 minutos de intervalo. A cada dez minutos, em uma nova sessão amostral, o foco era mudado para outro indivíduo do grupo. Adultos, subadultos e jovens foram observados. Os indivíduos de Callithrix sp. no JBRJ utilizam de forma diferenciada as categorias de utilização de habitat, com maior frequência a estratificação vertical inferior (entre 0 e 4,9m), suportes de diâmetro fino (até aproximadamente 14 cm de diâmetro), superfície média e inclinação horizontal (0 a 30), corroborando a outros estudos realizados que também verificaram estes padrões. Houve diferenças comportamentais dos indivíduos de Callithrix sp. no JBRJ entre as classes de machos e fêmeas adultos, subadultos e jovens. Os indivíduos machos realizaram com maior frequência todos os comportamentos. Resultados que contribuem para o conhecimento aprofundado sobre o comportamento desses primatas, no qual até então não tinham sido feitas comparações diretas entre as classes consideradas. Principalmente o resultado encontrado de que os machos são mais ativos que as demais classes, o que não é mencionado na literatura até o presente e favorece para compreendermos mais sobre essas espécies / Introduced populations of marmosets concern biologists and conservationists because of its potential occupancy of habitat, hybridization with native congeners, predation on representatives of the local fauna, disease transmission and competition with other species. It is necessary to understand which favors this flexible use of habitat and behavioral pattern which enables marmosets to survive in such diverse forest environments and even much altered and disturbed areas, such as large cities. Individuals of Callithrix sp.were followed at the Arboretum JBRJ. The fieldwork was done between August 2012 and August 2013 and accumulated a total of 205 hours of observations and 400 hours of sampling effort. The sampling method used was the " Focal Animal ", in which only one individual in the group was analyzed at a three minutes sampling session with 7 minutes apart. Every ten minutes, in a new sampling session, the animal focus was shifted to another individual in the group. Adults, sub-adults and young were observed. Individuals of Callithrix sp. in JBRJ use the categories of habitat differently, most often the lower vertical stratification (between 0 and 4.9 m), thinner supports (to about 14 cm diameter), with an average surface and a horizontal tilt (0 to 30 ), corroborating other studies that also found these patterns. There were also behavioral differences of individuals of Callithrix sp. in JBRJ between classes of male and female adults, sub-adults and youth. Male individuals used more frequently all behaviors. Results that contribute to the knowledge about the behavior of these primates, which had not been direct comparisons made between the classes considered. Mainly the result found that males are more active than the other classes, which is not mentioned in the literature to date and helps to understand more about these species.
74

Födoberikning av vitörade silkesapor (Callithrix jacchus) i djurpark : – En studie om vitörade silkesapors beteende och kostintag, samt hur de genom födoberikning kan stimuleras till ett naturligt beteende i djurpark.

Hedman, Pia, Hedvall Svensson, Anette January 2004 (has links)
<p>Det här arbetet syftar till att undersöka om och hur födoberikning kan stimulera vitörade silkesapor att utföra högre frekvenser av naturliga beteenden samt att se hur aktiva aporna är och om de frivilligt visar sig för publik på djurparken. Födoberikningen gick ut på att erbjuda aporna mat på ett mer naturligt sätt istället för att enbart ge dem maten i matskålar. Dessutom syftar arbetet till att erbjuda aporna en näringsmässigt korrekt sammansatt kost. Studien utfördes på två grupper av vitörade silkesapor på Parken Zoo i Eskilstuna under perioden juni till september år 2004. Undersökningen delades upp i tre perioder, under period 1 observerades aporna utan att någon födoberikning genomfördes. Under period 2 introducerades födoberikningen stegvis samtidigt som kostens sammansättning ändrades. Under period 3 var all födoberikning införd och kosten som erbjöds var näringsmässigt korrekt. Vår studie visar att frekvenserna av naturliga beteenden ökade vid födoberikning, det vill säga ätbeteende minskade, födosöksbeteende ökade och aggressiva/revir beteenden minskade. Socialt/övrigt beteende och förflyttning skilde sig åt mellan de två grupperna. Aporna blev mer aktiva och var mer synliga för publik under period 3. Vår matstudie visar att det är viktigt att utvärdera apornas kostintag på djurpark eftersom risken är stor att de inte erbjuds och äter rätt proportioner av olika näringsämnen.</p> / <p>The aim of this study is to examine whether and how food enrichment can stimulate the common marmoset to more frequently display natural behaviour patterns; also to see how active the monkeys are and if they voluntarily show themselves to the public in the zoo. The food enrichment meant offering food to the monkeys in a way more natural than simply providing it in bowls. In addition the aim is to provide a nutritionally balanced diet. The study was conducted on two groups of common marmosets in Parken Zoo in Eskilstuna from June 2004 to September 2004. The study was split into three periods. During period 1 the monkeys were observed without food enrichment. During period 2 food enrichment was introduced gradually while the diet changed. During period 3 all food enrichment was provided and the diet offered was nutritionally correct. Our study shows that natural behaviour became more frequent with food enrichment, that is, eating behaviour decreased, foraging behaviour increased and aggressive/territorial behaviour decreased. Social/other behaviour and motion differed between the two groups. The monkeys became more active and were more often visible to the public during period 3. Our feeding study shows the importance of evaluating the nutritional intake of the monkeys in a zoo, because of the risk that they are not offered or are not eating the right proportions of nutrients.</p>
75

Födoberikning av vitörade silkesapor (Callithrix jacchus) i djurpark : – En studie om vitörade silkesapors beteende och kostintag, samt hur de genom födoberikning kan stimuleras till ett naturligt beteende i djurpark.

Hedman, Pia, Hedvall Svensson, Anette January 2004 (has links)
Det här arbetet syftar till att undersöka om och hur födoberikning kan stimulera vitörade silkesapor att utföra högre frekvenser av naturliga beteenden samt att se hur aktiva aporna är och om de frivilligt visar sig för publik på djurparken. Födoberikningen gick ut på att erbjuda aporna mat på ett mer naturligt sätt istället för att enbart ge dem maten i matskålar. Dessutom syftar arbetet till att erbjuda aporna en näringsmässigt korrekt sammansatt kost. Studien utfördes på två grupper av vitörade silkesapor på Parken Zoo i Eskilstuna under perioden juni till september år 2004. Undersökningen delades upp i tre perioder, under period 1 observerades aporna utan att någon födoberikning genomfördes. Under period 2 introducerades födoberikningen stegvis samtidigt som kostens sammansättning ändrades. Under period 3 var all födoberikning införd och kosten som erbjöds var näringsmässigt korrekt. Vår studie visar att frekvenserna av naturliga beteenden ökade vid födoberikning, det vill säga ätbeteende minskade, födosöksbeteende ökade och aggressiva/revir beteenden minskade. Socialt/övrigt beteende och förflyttning skilde sig åt mellan de två grupperna. Aporna blev mer aktiva och var mer synliga för publik under period 3. Vår matstudie visar att det är viktigt att utvärdera apornas kostintag på djurpark eftersom risken är stor att de inte erbjuds och äter rätt proportioner av olika näringsämnen. / The aim of this study is to examine whether and how food enrichment can stimulate the common marmoset to more frequently display natural behaviour patterns; also to see how active the monkeys are and if they voluntarily show themselves to the public in the zoo. The food enrichment meant offering food to the monkeys in a way more natural than simply providing it in bowls. In addition the aim is to provide a nutritionally balanced diet. The study was conducted on two groups of common marmosets in Parken Zoo in Eskilstuna from June 2004 to September 2004. The study was split into three periods. During period 1 the monkeys were observed without food enrichment. During period 2 food enrichment was introduced gradually while the diet changed. During period 3 all food enrichment was provided and the diet offered was nutritionally correct. Our study shows that natural behaviour became more frequent with food enrichment, that is, eating behaviour decreased, foraging behaviour increased and aggressive/territorial behaviour decreased. Social/other behaviour and motion differed between the two groups. The monkeys became more active and were more often visible to the public during period 3. Our feeding study shows the importance of evaluating the nutritional intake of the monkeys in a zoo, because of the risk that they are not offered or are not eating the right proportions of nutrients.
76

Caracteriza??o citoarquitet?nica e por imunoistoqu?mica para tirosina-hidroxilase da subst?ncia negra, ?rea tegmentar ventral e zona retrorubral do Sagui (Callithrix jacchus)

Cavalcanti, Jos? Rodolfo Lopes de Paiva 30 April 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-08T23:56:19Z No. of bitstreams: 1 JoseRodolfoLopesDePaivaCavalcanti_TESE.pdf: 2156602 bytes, checksum: 000c3eafedc8a66a1a55425b0168fd4a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-11T23:46:45Z (GMT) No. of bitstreams: 1 JoseRodolfoLopesDePaivaCavalcanti_TESE.pdf: 2156602 bytes, checksum: 000c3eafedc8a66a1a55425b0168fd4a (MD5) / Made available in DSpace on 2016-04-11T23:46:45Z (GMT). No. of bitstreams: 1 JoseRodolfoLopesDePaivaCavalcanti_TESE.pdf: 2156602 bytes, checksum: 000c3eafedc8a66a1a55425b0168fd4a (MD5) Previous issue date: 2015-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Sabe-se que o grupo das catecolaminas ? integrado pela dopamina, noradrenalina e adrenalina e que a s?ntese dessas subst?ncias se d? de modo sequencial, sendo a enzima tirosina-hidroxilase reguladora da fase inicial deste processo. Neste sentido, a 3- hidroxitiramina/dopamina ? precursora da s?ntese de noradrenalina e adrenalina e ainda possui a capacidade de atuar como neurotransmissor na por??o central do sistema nervoso. Os tr?s principais n?cleos dopamin?rgicos, chamados zona retrorubral (grupo A8), subst?ncia negra pars compacta (grupo A9) e ?rea tegmentar ventral (grupo A10), est?o dispostos na por??o die-mesencef?lica e est?o envolvidos em tr?s vias, a mesostriatal, mesol?mbica e mesocortical. Estas vias est?o relacionadas diretamente com diversas manifesta??es comportamentais como controle da motricidade, sinaliza??o de recompensa na aprendizagem comportamental, motiva??o e nas manifesta??es patol?gicas da Doen?a de Parkinson e esquizofrenia. Considerando-se a relev?ncia desses, o objetivo do trabalho foi caracterizar morfologicamente os n?cleos dopamin?rgicos (A8, A9 e A10) do sagui (Callithrix jacchus) mediante estudo citoarquitet?nico e imunoistoqu?mico contra tirosina-hidroxilase. O sag?i ? um primata neotropical, cujas caracter?sticas morfofuncionais repercutem na adequabilidade de uso deste animal em pesquisas de ordem biom?dica. Sec??es coronais dos enc?falos de seis animais foram submetidas ? colora??o pelo m?todo de Nissl e immunoistoqu?mica para tirosinsa-hidroxilase. Com base na morfologia dos neur?nios, foi poss?vel subdividir o grupo A10 em sete regi?es: n?cleo interfascicular, linear rostral e linear caudal, situados na linha m?dia; paranigral e o parainterfascicular, situados na zona intermedi?ria; a por??o rostral da ?rea tegmentar ventral e o n?cleo parabraquial pigmentado, situados na por??o dorsolateral do tegmento mesencef?lico. O grupo A9 foi subdividido em quatro regi?es: subst?ncia negra camadas dorsal e ventral; subst?ncia negra conjuntos lateral e medial. Por ?ltimo, n?o foram indentificadas subdivis?es no grupo A8. Conclu?-se que A8, A9 e A10 s?o filogeneticamente conservados entre as esp?cies, por?m percebe-se a necessidade de se ampliar os estudos acerca das organiza??es subnucleares, seja investigando a sua ocorr?ncia em outras esp?cies de primatas, seja investigando a sua relev?ncia funcional. / It is known that the catecholamine group is constituted by dopamine, noradrenaline and adrenaline, in which the synthesis is regulated by an enzyme named tyrosine hydroxylase. Thus, 3-hydroxytyramine/dopamine (DA) is a precursor of the noradrenaline and adrenaline synthesis and acts as a neurotransmitter in the central nervous system. The three main nuclei, named the retrorubral field (A8 group), the substantia nigra pars compacta (A9 group) and the ventral tegmental area (A10 group), are arranged in the die-mesencephalic portion and are involved in three complexes circuitries - the mesostriatal, mesolimbic and mesocortical pathways. These pathways are related to behavioral manifestations, motricity, learning, reward and pathologies such as Parkinson?s Disease and Schizophrenia. Thus, the aim of this study was to perform de morphological analysis of the A8, A9 and A10 nuclei of the common marmoset (Callithrix jacchus). The marmoset is a neotropical primate, whose morphological and functional characteristics supports the suitability of use of this animal in biomedical research. Coronal sections of the marmoset brain were submitted to cytoarchitectonic characterization and TH-immunohistochemistry. Based on the morphology of the neurons, it was possible to subdivide the A10 group in seven regions: interfascicular nucleus, raphe rostral linear nucleus and raphe caudal linear nucleus, in the middle line; paranigral and parainterfascicular nucleus, in the middle zone; rostral portion of the ventral tegmental area nucleus and parabrachial pigmented nucleus, located in the dorsolateral portion of the mesencephalic tegmentum. A9 group was divided into four regions: substantia nigra compacta dorsal and ventral tiers; substantia nigra compacta lateral and medial clusters. No subdivisions were founded into A8 group. These results revealed that A8, A9 and A10 are phylogenetically conserved between species, but it?s necessary to expand the studies about this compartmentalization, investigating its occurrence in other primate species or investigating its functional relevance.
77

Infections of common marmosets with calpox virus

Kramski, Marit 29 January 2009 (has links)
Die vorsätzliche Freisetzung von Variola Virus (VARV) und schwere Erkrankungen des Menschen durch zoonotische Affen- (MPXV) und Kuh- (CPXV) pocken Viren stellen nach wie vor eine Bedrohung für die Bevölkerung dar. Klassische Pockenimpfstoffe bergen die Gefahr einer schweren Erkrankung. Deshalb ist die Entwicklung neuer Impfstoffe und Therapeutika von entscheidender Bedeutung. Deren Wirksamkeit und Sicherheit muss zunächst in verschiedenen Tiermodellen bewiesen werden. Existierende Makakken-Primatenmodelle leiden unter sehr artifiziellen Bedingungen der letalen Krankheitsinduktion durch VARV oder MPXV. Aus diesem Grund wurde das Calpox Virus/Krallenaffen-modell etabliert, welches auf einem CPXV aus natürlich infizierten Neuweltaffen (Marmosets) basiert. Das neue Modell hat drei wesentliche Vorteile: Die Arbeit mit Calpox Virus kann unter Sicherheitsstufe 2 durchgeführt werden und ist folglich einfacher in der Handhabung. 2. Die intranasale (i.n.) Infektion von Marmosets (Krallenaffen; Callithrix jacchus) spiegelt den natürlichen Infektionsweg von VARV wieder. Infizierte Affen entwickelten Pocken ähnliche Symptome und verstarben innerhalb von 2-3 Tagen nach Auftreten erster Symptome. Hohe Viruslasten wurden im Blut, Speichel und allen untersuchten Organen nachgewiesen. 3. Die i.n. Titration des Calpox Virus ergab eine 50 % Affen-Infektions-Dosis (MID50) von 8.3x102 pfu. Diese ist um den Faktor 10000 niedriger als in anderen Pocken-Primatenmodellen. Neun bis zehn Wochen nach einer Immunisierung mit dem Lister-Elstree Impfstoff waren alle Krallenaffen gegen eine letale Dosis des Calpox Virus (10 MID50) geschützt. Damit konnte der Nutzen des Calpox Virus/Krallenaffen-modells für die Erforschung neuer Impfstoffe gezeigt werden. Das Calpox Virus/Krallenaffen-modell überwindet wesentliche Nachteile bestehender Primatenmodelle und ist somit ein geeignetes Model für die Evaluierung von neuen Impfstoffen, Impfstrategien und antiviralen Therapien. / The intentional re-introduction of Variola virus (VARV), the agents of smallpox, into the human population remains of concern today. Moreover, zoonotic infections with Cowpox (CPXV) and Monkeypox virus (MPXV) cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antivirals have to be demonstrated by different animal models. The existing primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously to induce a lethal infection in macaque monkeys. To overcome these drawbacks, the main objective of this study was to develop a primate model in which a smallpox-like disease could be induced by a CPXV virus designated calpox virus which was isolated from a lethal orthopox virus (OPV) outbreak in New World monkeys (marmosets). The new non-human primate model has three major advantages: 1. Working with calpox virus is less challenging and can be done under bio-safety-level two. 2. Mimicking the natural route of VARV infection, intranasally infected marmosets (Callithrix jacchus) reproducibly developed clinical symptoms of an OPV infection and died within two to three days after onset of the first symptoms. High viral loads of calpox virus were detected in blood, saliva and all analyzed organs. 3. Intranasal titration of the virus resulted in a 50 % monkey infectious dose (MID50) of 8.3x102 pfu, a lethal infectious dose 10,000 lower than those used in any other primate model. Moreover, we showed the aptitude of the primate model for the testing of new vaccines since nine to ten weeks after immunization with Vaccinia virus Lister-Elstree marmosets were completely protected against intranasal challenge with 10 MID50 of calpox virus. As the calpox virus/marmoset model overcomes major limitations of current primate models it is suitable to evaluate new vaccines, new vaccination strategies and antiviral therapies.
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Improving the welfare of laboratory-housed primates through the use of positive reinforcement training : practicalities of implementation

Bowell, Verity A. January 2010 (has links)
Whilst there has been a recent increase in interest in using positive reinforcement training for laboratory-housed primates, there remains a reluctance to put into practice training programmes. Much of this reticence seems to stem from lack of expertise in the running of training programmes, and a perception that training requires a large time investment, with concurrent staff costs. The aim of this thesis was to provide practical recommendations for the use of training programmes in laboratories, providing primate users and carestaff with background information needed to successfully implement training programmes whilst improving the welfare of the animals in their care. Training was carried out with two species, cynomolgus macaques (Macaca fascicularis) and common marmosets (Callithrix jacchus) in three different research laboratories to ensure practicability was as wide ranging as possible. Training success and the time investment required were closely related to the primate's temperament, most notably an individual's willingness to interact with humans, in both common marmosets and cynomolgus macaques. Age and sex however had no effect on an individual's trainability. The training of common marmosets was more successful than that with cynomolgus macaques, possibly due to differences in early experience and socialisation. Positive reinforcement training helped both species to cope with the stress of cage change or cleaning, with the monkeys showing less anxiety-related behaviour following the training programme than before. Involving two trainers in the training process did not affect the speed at which common marmosets learned to cooperate with transport box training, but behavioural observations showed that initial training sessions with a new trainer led to animals experiencing some anxiety. This however was relatively transient. Whilst the training of common marmosets to cooperate with hand capture was possible, there seemed little benefit in doing so as the monkeys did not show a reduced behavioural or physiological stress response to trained capture as compared to hand capture prior to training. However strong evidence was found that following both training and positive human interactions the marmosets coped better with capture and stress was reduced. It is recommended that an increased use of early socialisation would benefit laboratory-housed primates, and would also help improve the success of training. Further, the time investment required shows that training is practicable in the laboratory for both species, and that positive reinforcement training is an important way of improving their welfare likely through reducing boredom and fear.
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Social contagion in common marmosets (Callithrix jacchus) : implications for cognition, culture and welfare

Watson, Claire F. I. January 2011 (has links)
The social transmission of social behaviours in nonhuman primates has been understudied, experimentally, relative to instrumental, food-related behaviours. This is disproportional in relation to the comparatively high percentage of potential social traditions reported in wild primates. I report a systematic survey of the social learning literature and provide quantitative evidence of the discrepancy (Watson and Caldwell, 2009). Addressing the identified deficit in experimental work on social behaviours, I also report three empirical studies investigating the contagious nature of affective states in captive, socially housed marmosets. I carried out an observational study, to determine whether marmosets are influenced by spontaneously produced neighbour calls to perform a range of behaviours associated with similar affect. My results supported a neighbour effect for anxiety in marmosets. Consistent with previous findings for chimpanzees (Baker and Aureli, 1996; Videan et al., 2005), I also found evidence for neighbour effects for aggression and affiliation (Watson and Caldwell, 2010). Through experimental playback, I investigated contingent social contagion in the auditory and visual modalities. The playback of pre-recorded affiliative (chirp) calls was found to be associated with marmosets spending increased time in a range of affiliative behaviours. Playback of video showing conspecifics engaged in a positive affiliative behaviour (allogrooming) also appeared to cause marmosets to spend longer performing various affiliative behaviours. My results indicate that social contagion of affiliation is a multi-modal phenomenon in marmosets and also represent the first evidence that allogrooming is visually contagious in primates. Sapolsky (2006) conceptualised culture as the performance of species-typical behaviours to an unusual extent, termed ‘social culture’. Researchers have yet to directly investigate a transmission mechanism. I investigated whether a social culture of increased affiliation could be initiated in marmosets through the long-term playback, of positive calls, or of video of positive behaviour. The results were consistent with a relatively long-lasting influence of the playback of affiliative calls across several affiliative behaviours. The effect appeared to last substantially beyond the specific hours of playback, between playbacks, and after playback had ceased, potentially indicating a temporary shift in social culture. These results are preliminary but provide some support for the proposal that auditory social contagion may be a transmission mechanism for social culture. The long-term video playback of allogrooming appeared to result in a transitory shift in performance of the identical behaviour (increased allogrooming) after playbacks had ceased. In addition to theoretical implications for social cognition and social culture, my findings have potential practical application for the enhancement of welfare in captive marmosets through sensory, and non-contact social, enrichment.
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Subcortical pathways for colour vision

Szmajda, Brett A. Unknown Date (has links) (PDF)
Visual sub-modalities, such as colour, form and motion perception, are analysed in parallel by three visual “pathways” – the parvocellular (PC), magnocellular (MC) and koniocellular (KC) pathways. This thesis aims to further elucidate some properties of the subcortical pathways for colour vision. The experimental animal used throughout is a New World monkey, the common marmoset Callithrix jacchus. (For complete abstract open document)

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