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

Do Severe Genetic Bottlenecks Lead to Greater Reproductive Failure?

Burrows, Ben Robert January 2006 (has links)
It is generally accepted that populations which experience severe bottlenecks have a reduction in fitness. One of the most frequently reported fitness costs is increased hatching failure in bottlenecked populations of birds. The mechanism responsible for increased hatching failure is unknown. Research on other animals suggest that reduced population numbers cause unavoidable inbreeding that in turn leads to abnormalities in the gametes. In this thesis I examine some of the possible causes for increased hatching failure in severely bottlenecked populations of introduced birds in New Zealand. I look at three traits identified as a cause for infertility or hatching failure previously and determine whether there is a link with the size of a population s bottleneck. It is possible that reduced numbers of sperm reaching the site of fertilisation is a primary cause of hatching failure. I examined the perivitelline membrane of various species of introduced birds and counted the total number of sperm present to compare to how many would be expected in non-bottlenecked species. Although there was no relationship between the size of the bottleneck and the number of sperm present, all species had lower than expected sperm counts. In many species of mammals, a reduction in the quality of sperm is attributed to inbreeding depression bought about by genetic bottlenecks. I next compared the level of sperm abnormalities, variation in midpiece size sperm, and sperm motility with the size of the bottleneck each species passed through when introduced to New Zealand. There was no significant correlation between either the variation in midpiece size or sperm motility with bottleneck size. However, there was a trend for species that passed through more severe bottlenecks to have a slightly higher level of midpiece size and lower motility. Finally, I examined whether there was a link between abnormalities in the eggshell and the size of the respective bottleneck. There was no significant change in eggshell thickness or any change in the number of pores associated bottleneck size. However, there was a decreased number of round pores in severely bottlenecked species, although the consequences of this are unknown. My findings do not directly link a single cause for increased hatching failure in bottlenecked species of birds, but they do highlight the need for monitoring of reproductive traits in endangered species that have experienced a population bottleneck.
2

Análise do viroma de soro de matrizes suínas com partos normais e com natimortalidade / Virome analysis on sera of sows with and without CASES of natimortality

Tochetto, Caroline January 2017 (has links)
Falhas reprodutivas são importante causa de prejuízos econômicos na suinocultura. Elas implicam na diminuição do número de leitões nascidos vivos e aumentam o descarte de animais e as taxas de reposição de matrizes, levando à redução da produtividade do rebanho. Embora a maioria dos casos de natimortalidade sejam associados a fatores não infecciosos, os agentes infecciosos possuem um papel importante e ainda pouco conhecido na etiologia deste quadro. Até o presente, nenhum trabalho foi realizado visando o estudo do conjunto de vírus que possam estar presentes em matrizes com eventos de natimortalidade por ocasião do parto. Em função disso, o presente trabalho teve por objetivo examinar o viroma do soro de matrizes suínas com e sem casos de natimortalidade. Foram coletadas 94 amostras de soro de matrizes de seis granjas distribuídas em cinco municípios do Rio Grande do Sul. Em cada granja foram formados dois pools de soros: um composto por matrizes que pariram (um ou mais) natimortos e outro por matrizes que pariram leitegadas sem natimortos. Os pools foram submetidos à extração de ácido nucleico viral, enriquecimento e sequenciamento de alto desempenho, buscando a identificação de agentes que possam representar um fator de risco à natimortalidade em suínos Não foi possível identificar diferenças significativas nos viromas de matrizes correlacionadas à ocorrência de natimortalidade. Não obstante, foi possível identificar uma ampla variedade de genomas virais, a maioria deles correspondendo a vírus das famílias Anelloviridae. Este estudo permitiu ainda identificar 20 genomas completos de três espécies de vírus: torque teno vírus suíno 1a e 1b, circovírus suíno tipo 3 (PCV3) e vírus circulares DNA fita simples codificantes de replicase (CRESS), seis dos quais até o presente ainda não reportados em suínos. Em duas granjas, em matrizes que apresentaram natimortalidade, foram identificados genomas de PCV3, cuja participação como potencial causador de problemas reprodutivos precisa ser futuramente investigada. Não foram identificados vírus com genoma de RNA. Este estudo traz uma contribuição ao conhecimento do viroma em soros de matrizes suínas e, paralelamente, busca contribuir para o esclarecimento das possíveis causas de natimortalidade de origem infecciosa em suínos. / Reproductive failure in swine herds is an important cause of economic losses. It leads to a decrease in the number of piglets reared per sow and may imply in the need for replacement of sows, reducing the productivity in a herd. Although the majority of cases of stillbirths have been attributed to non-infectious causes, several infectious agents have been implicated in the etiology of such condition. Nevertheless, other as yet unknown agents may be involved in the pathogenesis of stillbirths. The aim of this work was to investigate the virome in sera of sows without and with one or more cases of stillbirth in the litter. Sera were collected from 94 sows of six commercial farms in five municipalities in the state of Rio Grande do Sul, Brazil. Two pools of sera were collected from each farm: one representative of sows that had at least on stillbirth in the last litter and another composed by sera of sows that had litters with no stillbirths. The pools were subjected to nucleic acid extraction, enrichment and high throughput sequencing. No significant differences were detected in the serum viromes of sows with or without stillbirth Nevertheless, it was possible to identify a wide variety of viral genomes, most of these representing viruses of Anelloviridae family. In addition, the present work allowed the identification of 20 complete genome sequences including torque teno sus virus 1a and 1b, porcine circovirus 3 (PCV3) and circular rep-encoding ssDNA viruses (CRESS), including six species not previously reported in swine. In two farms, PCV3 genomes were identified in the serum pools of sows which had cases of stillbirth. The role for this virus as a potential cause of reproductive failure needs additional investigations. No genomes of viruses with RNA genomes were identified. This study provides a contribution to the knowledge on the serum virome of pregnant sows. In addition, it is expected to aid in the identification of possible causes of stillbirth in swine.
3

Do Severe Genetic Bottlenecks Lead to Greater Reproductive Failure?

Burrows, Ben Robert January 2006 (has links)
It is generally accepted that populations which experience severe bottlenecks have a reduction in fitness. One of the most frequently reported fitness costs is increased hatching failure in bottlenecked populations of birds. The mechanism responsible for increased hatching failure is unknown. Research on other animals suggest that reduced population numbers cause unavoidable inbreeding that in turn leads to abnormalities in the gametes. In this thesis I examine some of the possible causes for increased hatching failure in severely bottlenecked populations of introduced birds in New Zealand. I look at three traits identified as a cause for infertility or hatching failure previously and determine whether there is a link with the size of a population s bottleneck. It is possible that reduced numbers of sperm reaching the site of fertilisation is a primary cause of hatching failure. I examined the perivitelline membrane of various species of introduced birds and counted the total number of sperm present to compare to how many would be expected in non-bottlenecked species. Although there was no relationship between the size of the bottleneck and the number of sperm present, all species had lower than expected sperm counts. In many species of mammals, a reduction in the quality of sperm is attributed to inbreeding depression bought about by genetic bottlenecks. I next compared the level of sperm abnormalities, variation in midpiece size sperm, and sperm motility with the size of the bottleneck each species passed through when introduced to New Zealand. There was no significant correlation between either the variation in midpiece size or sperm motility with bottleneck size. However, there was a trend for species that passed through more severe bottlenecks to have a slightly higher level of midpiece size and lower motility. Finally, I examined whether there was a link between abnormalities in the eggshell and the size of the respective bottleneck. There was no significant change in eggshell thickness or any change in the number of pores associated bottleneck size. However, there was a decreased number of round pores in severely bottlenecked species, although the consequences of this are unknown. My findings do not directly link a single cause for increased hatching failure in bottlenecked species of birds, but they do highlight the need for monitoring of reproductive traits in endangered species that have experienced a population bottleneck.
4

Análise do viroma de soro de matrizes suínas com partos normais e com natimortalidade / Virome analysis on sera of sows with and without CASES of natimortality

Tochetto, Caroline January 2017 (has links)
Falhas reprodutivas são importante causa de prejuízos econômicos na suinocultura. Elas implicam na diminuição do número de leitões nascidos vivos e aumentam o descarte de animais e as taxas de reposição de matrizes, levando à redução da produtividade do rebanho. Embora a maioria dos casos de natimortalidade sejam associados a fatores não infecciosos, os agentes infecciosos possuem um papel importante e ainda pouco conhecido na etiologia deste quadro. Até o presente, nenhum trabalho foi realizado visando o estudo do conjunto de vírus que possam estar presentes em matrizes com eventos de natimortalidade por ocasião do parto. Em função disso, o presente trabalho teve por objetivo examinar o viroma do soro de matrizes suínas com e sem casos de natimortalidade. Foram coletadas 94 amostras de soro de matrizes de seis granjas distribuídas em cinco municípios do Rio Grande do Sul. Em cada granja foram formados dois pools de soros: um composto por matrizes que pariram (um ou mais) natimortos e outro por matrizes que pariram leitegadas sem natimortos. Os pools foram submetidos à extração de ácido nucleico viral, enriquecimento e sequenciamento de alto desempenho, buscando a identificação de agentes que possam representar um fator de risco à natimortalidade em suínos Não foi possível identificar diferenças significativas nos viromas de matrizes correlacionadas à ocorrência de natimortalidade. Não obstante, foi possível identificar uma ampla variedade de genomas virais, a maioria deles correspondendo a vírus das famílias Anelloviridae. Este estudo permitiu ainda identificar 20 genomas completos de três espécies de vírus: torque teno vírus suíno 1a e 1b, circovírus suíno tipo 3 (PCV3) e vírus circulares DNA fita simples codificantes de replicase (CRESS), seis dos quais até o presente ainda não reportados em suínos. Em duas granjas, em matrizes que apresentaram natimortalidade, foram identificados genomas de PCV3, cuja participação como potencial causador de problemas reprodutivos precisa ser futuramente investigada. Não foram identificados vírus com genoma de RNA. Este estudo traz uma contribuição ao conhecimento do viroma em soros de matrizes suínas e, paralelamente, busca contribuir para o esclarecimento das possíveis causas de natimortalidade de origem infecciosa em suínos. / Reproductive failure in swine herds is an important cause of economic losses. It leads to a decrease in the number of piglets reared per sow and may imply in the need for replacement of sows, reducing the productivity in a herd. Although the majority of cases of stillbirths have been attributed to non-infectious causes, several infectious agents have been implicated in the etiology of such condition. Nevertheless, other as yet unknown agents may be involved in the pathogenesis of stillbirths. The aim of this work was to investigate the virome in sera of sows without and with one or more cases of stillbirth in the litter. Sera were collected from 94 sows of six commercial farms in five municipalities in the state of Rio Grande do Sul, Brazil. Two pools of sera were collected from each farm: one representative of sows that had at least on stillbirth in the last litter and another composed by sera of sows that had litters with no stillbirths. The pools were subjected to nucleic acid extraction, enrichment and high throughput sequencing. No significant differences were detected in the serum viromes of sows with or without stillbirth Nevertheless, it was possible to identify a wide variety of viral genomes, most of these representing viruses of Anelloviridae family. In addition, the present work allowed the identification of 20 complete genome sequences including torque teno sus virus 1a and 1b, porcine circovirus 3 (PCV3) and circular rep-encoding ssDNA viruses (CRESS), including six species not previously reported in swine. In two farms, PCV3 genomes were identified in the serum pools of sows which had cases of stillbirth. The role for this virus as a potential cause of reproductive failure needs additional investigations. No genomes of viruses with RNA genomes were identified. This study provides a contribution to the knowledge on the serum virome of pregnant sows. In addition, it is expected to aid in the identification of possible causes of stillbirth in swine.
5

Análise do viroma de soro de matrizes suínas com partos normais e com natimortalidade / Virome analysis on sera of sows with and without CASES of natimortality

Tochetto, Caroline January 2017 (has links)
Falhas reprodutivas são importante causa de prejuízos econômicos na suinocultura. Elas implicam na diminuição do número de leitões nascidos vivos e aumentam o descarte de animais e as taxas de reposição de matrizes, levando à redução da produtividade do rebanho. Embora a maioria dos casos de natimortalidade sejam associados a fatores não infecciosos, os agentes infecciosos possuem um papel importante e ainda pouco conhecido na etiologia deste quadro. Até o presente, nenhum trabalho foi realizado visando o estudo do conjunto de vírus que possam estar presentes em matrizes com eventos de natimortalidade por ocasião do parto. Em função disso, o presente trabalho teve por objetivo examinar o viroma do soro de matrizes suínas com e sem casos de natimortalidade. Foram coletadas 94 amostras de soro de matrizes de seis granjas distribuídas em cinco municípios do Rio Grande do Sul. Em cada granja foram formados dois pools de soros: um composto por matrizes que pariram (um ou mais) natimortos e outro por matrizes que pariram leitegadas sem natimortos. Os pools foram submetidos à extração de ácido nucleico viral, enriquecimento e sequenciamento de alto desempenho, buscando a identificação de agentes que possam representar um fator de risco à natimortalidade em suínos Não foi possível identificar diferenças significativas nos viromas de matrizes correlacionadas à ocorrência de natimortalidade. Não obstante, foi possível identificar uma ampla variedade de genomas virais, a maioria deles correspondendo a vírus das famílias Anelloviridae. Este estudo permitiu ainda identificar 20 genomas completos de três espécies de vírus: torque teno vírus suíno 1a e 1b, circovírus suíno tipo 3 (PCV3) e vírus circulares DNA fita simples codificantes de replicase (CRESS), seis dos quais até o presente ainda não reportados em suínos. Em duas granjas, em matrizes que apresentaram natimortalidade, foram identificados genomas de PCV3, cuja participação como potencial causador de problemas reprodutivos precisa ser futuramente investigada. Não foram identificados vírus com genoma de RNA. Este estudo traz uma contribuição ao conhecimento do viroma em soros de matrizes suínas e, paralelamente, busca contribuir para o esclarecimento das possíveis causas de natimortalidade de origem infecciosa em suínos. / Reproductive failure in swine herds is an important cause of economic losses. It leads to a decrease in the number of piglets reared per sow and may imply in the need for replacement of sows, reducing the productivity in a herd. Although the majority of cases of stillbirths have been attributed to non-infectious causes, several infectious agents have been implicated in the etiology of such condition. Nevertheless, other as yet unknown agents may be involved in the pathogenesis of stillbirths. The aim of this work was to investigate the virome in sera of sows without and with one or more cases of stillbirth in the litter. Sera were collected from 94 sows of six commercial farms in five municipalities in the state of Rio Grande do Sul, Brazil. Two pools of sera were collected from each farm: one representative of sows that had at least on stillbirth in the last litter and another composed by sera of sows that had litters with no stillbirths. The pools were subjected to nucleic acid extraction, enrichment and high throughput sequencing. No significant differences were detected in the serum viromes of sows with or without stillbirth Nevertheless, it was possible to identify a wide variety of viral genomes, most of these representing viruses of Anelloviridae family. In addition, the present work allowed the identification of 20 complete genome sequences including torque teno sus virus 1a and 1b, porcine circovirus 3 (PCV3) and circular rep-encoding ssDNA viruses (CRESS), including six species not previously reported in swine. In two farms, PCV3 genomes were identified in the serum pools of sows which had cases of stillbirth. The role for this virus as a potential cause of reproductive failure needs additional investigations. No genomes of viruses with RNA genomes were identified. This study provides a contribution to the knowledge on the serum virome of pregnant sows. In addition, it is expected to aid in the identification of possible causes of stillbirth in swine.
6

Descarte de fêmeas suínas em granjas de quarto sítio e em unidades produtoras de leitões com reposição de leitoas gestantes: eficiência reprodutiva e validação das razões atribuídas para o descarte / Culling of female swine in four-site and piglet-production units with pregnant replacement gilts: reproductive efficiency and validation of recorded culling reasons

Ulguim, Rafael da Rosa 25 March 2011 (has links)
Made available in DSpace on 2014-08-20T14:38:04Z (GMT). No. of bitstreams: 1 dissertacao_rafael_ulguim.pdf: 242678 bytes, checksum: 818cdda987f14895f73f146504604940 (MD5) Previous issue date: 2011-03-25 / In conventional swine production systems, with acquisition of replacement gilts either from commercial suppliers or internal replacement, high culling rates are associated with reduced productive efficiency. The culling pattern of alternative replacement systems, consisting of four-site units (4S) that prepare replacement gilts to be sold pregnant to piglet-production units (PP) are not yet characterized. The objectives of this study are: to characterize the culling pattern and the associations between the culling reasons and female reproductive efficiency in 4S and PP units; and to associate culling reasons recorded at farm level with examining genital organs of culled females at a slaughterhouse. Individual female records of culled females (n = 5,013) were extracted from databases of three 4S units and ten PP units. A frequency distribution was generated for the culling reasons, which were classified as: reproductive failure, low productivity, age, locomotor problems; and other causes. The evaluated parameters of reproductive efficiency were: herd lifetime; non productive days (NPD); and total number of piglets born during herd lifetime (PBL), per parity (PBP) and per year of herd lifetime (PBY). Such parameters were compared according to the production units, parity at culling (PC) and culling reason. At the slaughterhouse, the uterus and the ovaries of 311 culled females from the same 13 units were evaluated. Culling for locomotor problems was more frequent in 4S units, whereas culling for low productivity was more frequent in PP units. In 4S units, herd lifetime was 71.8 ± 0.8 d and the first service to culling interval was 57.1 ± 0.8 d. In the PP units, herd lifetime was 672.5 ± 7.1 d and PC was 4.4 ± 0.1. Parameters related to piglets production over time were similar to those observed in conventional production systems, with the lowest PBL (33.5 ± 1.1) observed for females culled for reproductive failure and PBY (22.8 ± 0.3) for those culled for productivity. At the slaughterhouse evaluation, the frequency of ovaries presenting cysts and no structures were 12.6% and 10.9%, respectively. No association was observed among such pathologies and the reproductive failures recorded as the reasons for female culling (P > 0.05). The production system combining 4S and PP units presented PC somewhat increased and decreased NPD, in comparison with conventional replacement systems, indicating a potential for increasing female retention rates and reducing the impact of premature female culling on herd reproductive efficiency. / Em sistemas convencionais de produção de suínos, com aquisição de fêmeas de reposição de fornecedores externos ou com reposição interna, a alta taxa de descarte de fêmeas é associada com menor eficiência produtiva. Sistemas alternativos de reposição, com unidades de Quarto Sítio (4S) para a preparação de leitoas de reposição que são vendidas gestantes para unidades de produção de leitões (UPL), não possuem o padrão de descarte caracterizado. Os objetivos deste trabalho foram: caracterizar os descartes em 4S e UPL e a relação das causas de descarte com indicadores de eficiência reprodutiva; e associar as causas de descarte atribuídas na granja às falhas reprodutivas com o exame de órgãos genitais das fêmeas descartadas, no frigorífico. Registros individuais de 5.013 fêmeas descartadas foram extraídos do banco de dados de três unidades de 4S e dez UPL. Distribuições de frequencia foram geradas para as razões de descarte, que foram divididas em: falhas reprodutivas; produtividade; idade; problemas locomotores; e causas diversas. Os indicadores de eficiência reprodutiva avaliados incluíram: tempo de permanência no plantel; dias não produtivos (DNP); e total de leitões nascidos durante a vida reprodutiva (TN), por parto (MN) e por ano (NPA). Estes indicadores foram comparados em função da unidade de produção, da ordem de parto ao descarte (OP) e da razão atribuída para o descarte. No frigorífico, foram avaliados os ovários e o útero de 311 fêmeas descartadas das 13 granjas selecionadas. Os descartes por problemas locomotores foram os mais frequentes nas unidades de 4S, enquanto que os descartes por baixa produtividade foram os mais frequentes nas UPL. Nas unidades de 4S, o tempo médio de permanência foi de 71,8 ± 0,8 d e intervalo primeiro serviço-descarte de 57,1 ± 0,8 d. Nas UPL, o tempo de permanência foi de 672,5 ± 7,1 d e a OP média foi de 4,4 ± 0,1. Os indicadores de produtividade relacionados a produção de leitões, mostraram padrão semelhante ao verificado em sistemas convencionais, onde o TN foi menor para os descartes por falha reprodutiva (33,5 ± 1,1), assim como o NPA nos descartes por produtividade (22,8 ± 0,3) foi inferior as demais razões de descarte. No frigorífico, a frequência de ovários lisos foi de 10,9% e a de cistos ovarianos de 12,6%. Não houve associação entre as patologias observadas e a causa atribuída para o descarte por falhas reprodutivas. O sistema de produção que combina unidades de 4S e UPL apresentou uma OP média ao descarte relativamente elevada e uma redução no acúmulo de DNP, o que indica a possibilidade de maior taxa de retenção de fêmeas e redução do impacto produtivo do descarte precoce de fêmeas sobre a eficiência reprodutiva.
7

Detecção de parvovírus suíno em material proveniente de porcas com patologias reprodutivas / Detection of porcine parvovirus in material from sows with reproductive disorders

Rocha, Camila Andréa Salvitti de Sá 13 May 2010 (has links)
Made available in DSpace on 2016-12-08T16:24:06Z (GMT). No. of bitstreams: 1 PGCA10MA046.pdf: 2836538 bytes, checksum: df03fbb548e05bbfeb41e5f0f1ba5a4f (MD5) Previous issue date: 2010-05-13 / Porcine parvovirosis is a disease that causes reproductive failure and its causative agent is the Porcine Parvovirus Type 1 (PPV1). This disease, with high prevalence and worldwide distribution, affects mostly non-immune nulliparous sows. Clinically, it is observed return to estrus, delayed parturition date, birth of unviable piglets, weak, stillborn and particularly mummified fetuses in different sizes. These reproductive problems lead economic losses demonstrated by low productivity. This study aimed to implement and validate techniques for laboratory diagnosis PPV1 in natural infections in pig herds with reproductive problems and perform the characterization of these isolates. More specifically, it aimed to diagnose through nested-PCR, and characterize, through phylogenetic analysis, PPV1 isolates from tissue samples and stomach fluid from fetuses and reproductive tract from culled sows. The objectives were to further evaluate histologically the tissues that were positive by nested-PCR; to standardize an internal amplification control (IAC) for PVS1 nested-PCR; to standardize immunohistochemistry technique (IHC) in fetal tissues and to standardize PCR for Porcine Parvovirus Type 4 (PPV4). A total of 27 pig herds were studied, where 230 fetuses stillborn, mummified, aborted and unviable piglets were necropsied to harvest organs and stomach fluid. PPPV1 viral DNA was detected by nested-PCR in organs of six (2.61%) out of 230 fetuses analyzed, the cerebellum and spinal cord were the organs where the virus was detected more frequently (50%). Stomach fluids of three (2.75%) fetuses were positive by nested-PCR, out of 109 examined. In addition, samples of reproductive organs from 83 culled sows were collected also ovarian follicular fluid from 71 of them. The genetic material of PPV1 was diagnosed in six organs from sows (7.23%) and follicular fluid of three (4.22%) of them. Histological lesions were observed in four of 19 PPV1 positive organs of fetuses. Also, six ovaries and six uteri of six culled sows were PPV1 positive by nested-PCR. Exams showed that five of those ovaries were cycling, one was in anestrous and four uterus had some degree of endometritis. The IAC developed for nested-PCR was amplified in all reactions, as expected. In the IHC test the virus presence was confirmed in fetal tissue. The PCR for PPV4 was standardized and tested in fetal organs and reproductive organs from culled sows. Some samples from sow s reproductive organs were positive for this new porcine parvovirus. The results from this study show a low detection of PPV1 in herds analyzed, as well as from the reproductive organs of culled sows, considering the reduced PPV1 involvement in reproductive failure. Moreover, standardized techniques can be incorporated into routine diagnostic of PPV1 and PPV4 / A parvovirose suína é uma doença causadora de falhas reprodutivas e seu agente etiológico é o Parvovírus Suíno Tipo 1 (PVS1). Essa enfermidade, de alta prevalência e distribuição mundial, afeta principalmente porcas nulíparas não imunes. Clinicamente observa-se retorno ao cio, atraso na data de parição, nascimento de leitões inviáveis, fracos, natimortos e, principalmente, mumificados em diferentes tamanhos. Estes problemas reprodutivos acarretam prejuízos econômicos demonstrados pelos baixos índices produtivos. O presente trabalho objetivou implantar e validar técnicas de diagnóstico laboratorial para detecção de PVS1 em infecções naturais em rebanhos suínos que apresentam problemas reprodutivos e realizar caracterização desses isolados. Mais especificamente, objetivou-se diagnosticar, através de nested-PCR, e caracterizar, através de análise filogenética, isolados de PVS1 em amostras de tecidos e líquido estomacal de fetos e em aparelho reprodutivo de porcas descartadas. Objetivou-se ainda avaliar histologicamente os tecidos que resultaram positivos na nested-PCR; padronizar um controle interno de amplificação (CIA) para a nested-PCR de PVS1; padronizar técnica de imunohistoquímica (IHQ) em tecidos fetais e padronizar PCR para Parvovírus Suíno Tipo 4 (PVS4). De 27 rebanhos de suínos, foram colhidos 230 fetos entre natimortos, mumificados e abortados, os quais foram necropsiados para colheita de órgãos e líquido estomacal. O DNA viral foi detectado por nested-PCR em órgãos de seis (2,61%) fetos dos 230 analisados, sendo o cerebelo e a medula os órgãos onde o vírus foi detectado com maior frequência (50%). Líquido estomacal de três (2,75%) fetos foram positivos por nested-PCR, de 109 analisados. Além disso, amostras de órgãos reprodutivos de 83 porcas descartadas foram colhidas e também fluido folicular ovariano de 71 delas. O material genético do PVS1 foi diagnosticado em órgãos de seis porcas (7,23%) e em fluido folicular de três (4,22%) delas. De 19 órgãos positivos de fetos na nested-PCR, quatro tiveram lesão histológica. De seis ovários e seis úteros das seis fêmeas suínas descartadas positivas na nested-PCR, cinco ovários estavam ciclando, um estava em anestro e quatro úteros tinham algum grau de endometrite. O CIA desenvolvido para a nested-PCR foi amplificado em todas as reações, conforme o esperado. Nos testes de IHQ a presença do vírus foi confirmada em tecido fetal. A PCR para o PVS4 foi padronizada e testada em órgãos fetais e de porcas descartadas. Algumas amostras de porcas foram positivas para este novo parvovírus suíno. Os resultados obtidos no estudo evidenciam baixa freqüência do PVS1 nos rebanhos analisados, bem como nos órgãos reprodutivos de porcas descartadas, considerando baixo o envolvimento do PVS1 nas falhas reprodutivas. Além disso, as técnicas padronizadas podem ser incorporadas na rotina de diagnóstico de PVS1 e PVS4
8

Estudo da patogenicidade e investigação de coinfecção por circovirus suíno e torque teno vírus suíno em material proveniente de porcas com patologias reprodutivas / Pathogenicity study and co-infection investigation by Porcine Circovirus and Swine Torque Teno Virus in materials from sows with reproductive failure

Ritterbusch, Giseli Aparecida 06 November 2009 (has links)
Made available in DSpace on 2016-12-08T16:24:07Z (GMT). No. of bitstreams: 1 PGCA09MA052.pdf: 726948 bytes, checksum: 2a141d4d92b1c5ac552655f7c9ad3c1a (MD5) Previous issue date: 2009-11-06 / Many infectious agents have been associated with reproductive failure in swine, representing significantly economic losses for production. Recently, Porcine Circovirus Type 2 (PCV2), etiologic agent of PCVAD or PCV2 associated diseases, was associated with reproductive failure in swine around the world. To confirm the pathogenic potential of PCV2 inducing reproductive failure in sows, it s necessary the viral isolation and antigen and nucleic acid demonstration in fetuses. Other viral agent, Torque Teno Vírus (TTV), also have been recently associated with infections caused by PCV2. TTV alone has not showed pathogenic signals in swine, but, its role in co-infections with other pathogens has been investigated. The present study aimed the diagnostic of PCV2 in natural infections where there was reproductive failure, as well as to establish and apply the Polimerase Chain Reaction (PCR) technique for TTV from organs. Samples from field cases, as aborted fetuses, mummified, stillborn, fragile piglets and material from abattoir sows were collected and processed to diagnostic infection in order to detect PCV2 by PCR and immunohistochemistry (IHC). Samples were collected from 21 farms; and a total of 169 fetuses were necropsied. Moreover, reproductive samples from 83 abattoir sows were collected in 4 slaughterhouses of Santa Catarina State. In the present study was possible detect viral DNA by PCR in 29 (17,1%) of 169 analyzed fetuses, where heart and lymphoid tissues showed virus DNA more frequently, 41,4% and 37,8%, respectively. Viral presence was confirmed by IHC in tissues, which detected viral antigens in 17 PCV2 positives fetuses by PCR. Samples of reproductive tissues from sows also were tested by PCR and PCV2 was identified in 4 sows (4,8%). PCR technique aimed to detect TTV was established for viral DNA from organs. Samples of reproductive tissues from sows were tested, and were found both genogroups of TTV (TTV1 and TTV2), in 25 (30,1%) and 41 (49,3%) sows, respectively. Fetuses samples that resulted positive to PCV2 by PCR were also tested to TTV, and it was observed the occurrence of co-infection between these agents. The results obtained here suggest the involvement of PCV2 in reproductive failure in sows, besides show that TTV was present in analyzed samples, corroboring the association with PCV2 / Muitos agentes infecciosos têm sido associados às falhas reprodutivas na produção de suínos, representando significativas perdas econômicas para os suinocultores. Recentemente o Circovirus Suíno tipo 2 (PCV2), agente etiológico da circovirose suína, foi associado a falhas reprodutivas em suínos em diversas partes do mundo. Para confirmar o potencial patogênico do PCV2 causando falhas reprodutivas em porcas, é necessário o isolamento do vírus e demonstração de antígeno e ácido nucléico viral em fetos. Outro agente viral, o Torque Teno Vírus (TTV), também foi recentemente associado às infecções causadas pelo PCV2. O TTV sozinho ainda não tem se mostrado patogênico em suínos, porém, seu papel em co-infecções com outros patógenos vem sendo investigado. O presente trabalho teve por objetivos diagnosticar o PCV2 em infecções naturais onde existiam falhas reprodutivas, assim como padronizar e aplicar a técnica de Reação em Cadeia da Polimerase (PCR) para TTV a partir de órgãos. Amostras provenientes de casos clínicos de campo, como fetos abortados, mumificados, natimortos, leitões inviáveis e material de fêmeas descartadas foram coletadas e processadas para diagnóstico da infecção pelo PCV2 através de PCR e imunoistoquímica (IHQ). Foram colhidas amostras de 21 granjas produtoras de suínos, totalizando 169 fetos, que foram necropsiados para coleta de órgãos. Além disso, amostras de órgãos reprodutivos de 83 fêmeas descartadas foram colhidas em 4 abatedouros da região oeste catarinense. No presente estudo foi possível detectar DNA viral por PCR em 29 (17,1%) dos 169 fetos analisados, sendo coração e tecidos linfóides os órgãos onde o vírus foi identificado com maior freqüência, 41,4% e 37,8%, respectivamente. A presença do vírus foi confirmada por teste de IHQ dos tecidos, sendo encontrado antígeno viral em 17 fetos positivos para PCV2 por PCR. As amostras de tecido reprodutivo das fêmeas também foram testadas por PCR e o PCV2 foi identificado em 4 porcas (4,8%). Visando a detecção de TTV foram testadas por PCR amostras de órgãos reprodutivos de fêmeas suínas, sendo diagnosticados os dois genogrupos de TTV, TTV1 e TTV2 em 25 (30,1%) e 41 (49,3%) fêmeas, respectivamente. As amostras de fetos que resultaram positivas para PCV2 pela técnica de PCR também foram testadas para TTV, observando-se a ocorrência de coinfecção entre estes agentes. Os resultados obtidos evidenciam o provável envolvimento do PCV2 em falhas reprodutivas em fêmeas suínas, bem como mostram que o TTV está presente nas amostras analisadas, confirmando a associação com o PCV2
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Population demographics of New Zealand fur seals (Arctocephalus forsteri)

McKenzie, Jane, janemckenzie@malpage.com January 2006 (has links)
Assessment of trophic interactions between increasing populations of New Zealand fur seals (Arctocephalus forsteri) and fisheries in southern Australia is limited due to a lack of species specific demographic data and an understanding of the factors influencing population growth. To establish species specific demographic parameters a cross-sectional sample of New Zealand fur seal females (330) and males (100) were caught and individually-marked on Kangaroo Island, South Australia between 2000 and 2003. The seals were aged through examination of a postcanine tooth, which was removed from each animal to investigate age-specific life-history parameters. Annual formation of cementum layers was confirmed and accuracy in age estimation was determined by examination of teeth removed from individuals of known-age. Indirect methods of assessing reproductive maturity based on mammary teat characteristics indicated that females first gave birth between 4-8 years of age, with an average age at reproductive maturity of 5 years. Among reproductively mature females, age-specific reproductive rates increased rapidly between 4-7 years of age, reaching maximum rates of 70-81% between 8-13 years, and gradually decreased in older females. No females older than 22 years were recorded to pup. Age of first territory tenure in males ranged from 8-10 years. The oldest female and male were 25 and 19 years old, respectively. Post-weaning growth in females was monophasic, characterised by high growth rates in length and mass during the juvenile growth stage, followed by a gradual decline in growth rates after reproductive maturity. In contrast, growth in males was biphasic and displayed a secondary growth spurt in both length and mass, which coincided with sexual and social maturation, followed by a rapid decline in growth rates. Age-specific survival rates were high (0.823-0.953) among prime-age females (8-13 yrs of age) and declined in older females. Relative change in annual pup production was strongly correlated with reproductive rates of prime-age females and adult female survival between breeding seasons.

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