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Abstract(s)
O agente etiológico da circovirose suína é um vírus de pequenas dimensões, conhecido por
Porcine Circovirus in Suine (PCV). O PCV é considerado um vírus ubiquitário, que causa
doença exclusivamente em suínos e já isolado em todos os continentes. Este vírus é
responsável por várias infeções, sendo a mais comum e responsável por maiores perdas
económicas no sector suínicola, o síndrome de emagrecimento pós-desmame (PMWS).
Existem também outros fatores de risco que predespoem à manifestação clínica da doença
nomeadamente, as deficiências no maneio, a presença de coinfecções, estatuto imunitário
das reprodutoras contra o PCV2 e imuno-estimulação por diferentes causas.
As lesões e sinais clínicos associados à infeção por PCV sugerem que este seja um agente
imunossupressor/imunomodulador. O controlo e a prevenção do PCV passa pela
minimização do efeito dos factores de risco e pela vacinação contra a PCV.
O presente estudo teve como objetivo principal investigar o efeito da aplicação da vacina
contra a circovirose em porcas reprodutoras na fertilidade, prolificidade, produtividade,
peso ao nascimento e o peso ao desmame numa exploração comercial, onde na prática
corrente apenas se aplica a vacina contra o PCV2 à descendência. Também se pretende
analisar o efeito que esta aplicação poderá ter no resultado económico. Cinquenta e cinco
porcas foram vacinadas e como grupo controlo foram utilizadas um número idêntico
de porcas não vacinadas.
A vacinação das porcas levou a um aumento da taxa de fertilidade e taxa de partos, mas
também a um maior número de leitões nascidos vivos por ninhada, embora com menor peso
médio comparativamente com o grupo de porcas não vacinadas, o que conduziu a igual peso
ao nascimento por ninhada entre ambos os grupos. O peso por ninhada desmamada não
diferiu entre os grupos mas o número de leitões desmamados foi maior no grupo das porcas
vacinado.
No final do período de engorda, o peso individual dos animais também não entre os dois
grupos. A vacinação levou a uma redução da taxa de mortalidade em todas as fases
produtivas. Os resultados mostram que a vacinação das porcas reprodutoras leva a
melhorias nos parâmetros reprodutivos e também do desempenho produtivo da exploração,
com consequentes benefícios económicos.
The etiologic agents of circovirosis is a small virus known as Porcine Circovirus (PCV). The PCV is considered a ubiquitous virus that causes disease only in pigs and has been isolated from all continents. This virus is responsible for various affections, being the most common and responsible by major economic losses in the sector, the Postweaning Multisystemic Wasting Syndrome (PMWS). There are several risk factors that predispose animals to manifestation of clinical signs of disease, such as deficiencie management practices, the presence of co-infections, immune status of sows against PCV and immuno-stimulation by different causes. The clinical signs and lesions associated with infection with PCV2 suggest that this is an immunosuppressant/immunomodulating agent. The control and prevention of PCVD involve the minimizing of effect of risk factors and vaccination against PCV2. The present study aimed to evaluate the effect of the application of the vaccine against the circovirosis disease in sows on fertility, prolificacy, productivity, birth weight and weaning in a commercial farm, where the previous practice consisted only in application of the PCV2 vaccine to the piglets. The economic impact of the vaccine application to sows was also evaluated. Fifty five sows were vaccinated and control group was composed by identical number of unvaccinated sows. Vaccination of sows led to increase of the fertility farrowing rates, and number of live-born piglets per litter. However, birth weight was lower in piglets from vaccinated sows than from unvaccinanted sows,leading to the equal litrth weight in both vaccinate and unvaccinated groups. The litter weaning weight did not differ between groups, but the number of weaned piglets increased with vaccination. At the end of the fattening period, the individual weight of the animals did differ between groups. Vaccination led to a reduction in the mortality rate in all production phases. The results show that the vaccination of sows leads to improvements in the reproductive parameters, as well as in production performance of the farm, with consequent economic benefits.
The etiologic agents of circovirosis is a small virus known as Porcine Circovirus (PCV). The PCV is considered a ubiquitous virus that causes disease only in pigs and has been isolated from all continents. This virus is responsible for various affections, being the most common and responsible by major economic losses in the sector, the Postweaning Multisystemic Wasting Syndrome (PMWS). There are several risk factors that predispose animals to manifestation of clinical signs of disease, such as deficiencie management practices, the presence of co-infections, immune status of sows against PCV and immuno-stimulation by different causes. The clinical signs and lesions associated with infection with PCV2 suggest that this is an immunosuppressant/immunomodulating agent. The control and prevention of PCVD involve the minimizing of effect of risk factors and vaccination against PCV2. The present study aimed to evaluate the effect of the application of the vaccine against the circovirosis disease in sows on fertility, prolificacy, productivity, birth weight and weaning in a commercial farm, where the previous practice consisted only in application of the PCV2 vaccine to the piglets. The economic impact of the vaccine application to sows was also evaluated. Fifty five sows were vaccinated and control group was composed by identical number of unvaccinated sows. Vaccination of sows led to increase of the fertility farrowing rates, and number of live-born piglets per litter. However, birth weight was lower in piglets from vaccinated sows than from unvaccinanted sows,leading to the equal litrth weight in both vaccinate and unvaccinated groups. The litter weaning weight did not differ between groups, but the number of weaned piglets increased with vaccination. At the end of the fattening period, the individual weight of the animals did differ between groups. Vaccination led to a reduction in the mortality rate in all production phases. The results show that the vaccination of sows leads to improvements in the reproductive parameters, as well as in production performance of the farm, with consequent economic benefits.
Description
Dissertação de mestrado apresentada na área Produção e Tecnologia Animal, na Escola Superior Agrária de Santarém, do Instituto Politécnico de Santarém.
Keywords
Suíno Circovirus porcino Prevenção da doença Porca Vacina Desempenho reprodutivo Prolificidade Leitão Crescimento
Citation
Jerónimo, Cândida Eulália Sousa (2015). Efeitos da vacina contra a circovirose suína sobre os parâmetros reprodutivos e produtivos em porcas reprodutoras e o seu impacto económico. 55 p.Dissertação apresentada para obtenção do grau de Mestre na área de Produção e Tecnologia Animal, na Escola Superior Agrária de Santarém.