Estudo prospetivo da variação de anticorpos anti-neospora caninum em vacas leiteiras
Miniatura indisponível
Data
2020
Autores
Título da revista
ISSN da revista
Título do Volume
Editora
Resumo
Neospora caninum é um parasita protozoário intracelular obrigatório que causa
Neosporose bovina. É uma doença com distribuição mundial associada a abortos, refugo
involuntário de animais e diminuição da produção de leite, causando enormes perdas
económicas. Pretendeu-se com o presente trabalho determinar a sua prevalência na exploração
Casal de Quintanelas de 16 de Junho a 06 de Novembro de 2018, verificar se a entrada ou saída
de animais positivos para o tanque de leite se traduzia em alguma alteração no nível de
anticorpos no mesmo, se os animais apresentavam diferentes valores nos anticorpos em
diferentes fases de produção e se existia uma correlação de positividade entre mães e filhas.
Para tal utilizou-se amostras de soro sanguíneo (98 amostras) e leite individual (623 amostras)
ou do tanque (22 amostras) para realizar o teste ELISA CIVTESTÒ BOVIS
NEOSPORA – HIPRA. A prevalência de Neospora caninum foi de 27,1% num total de 461
bovinos fêmeas, valor que se encontra próximo ou dentro dos intervalos já estudados
anteriormente no nosso país. De 181 vacas analisadas, 21% seroconverteram, tornando-se
positivas no final da gestação (valores de IRPC das fases de lactação e secagem negativos, e
positivos no parto). Apesar de existir alteração no valor de anticorpos com a entrada ou saída
de animais para o tanque de leite, não foi detetada uma associação estatisticamente significativa
entre este e a proporção de animais positivos em cada tanque. Verificou-se que
maioritariamente a transmissão é vertical pois mais de 50% das mães positivas tiveram filhas
positivas. A falta de associação entre a seropositividade de mães e filhas e a existência de filhas
positivas de mães negativas indicou-nos que também existiu transmissão horizontal na
exploração. Observou-se ainda uma distribuição uniforme de animais seropositivos entre os
grupos etários. A frequência relativa de abortos não foi considerada normal (2,6%), devendo
ser considerada importante e sendo necessário tomar medidas para a reduzir, tal como a adoção
de medidas de prevenção da infeção. A fim de reduzir ou prevenir a Neosporose bovina na
exploração, foi aconselhada, sempre que possível, e tendo em conta questões económicas, a
aplicação de medidas de prevenção e controle específicas para esta doença.
Neospora caninum is a mandatory intracellular protozoan parasite that causes Bovine Neosporosis. It is a worldwide disease associated with abortions, involuntary culling of animals and decreased milk production, causing huge economic losses. The aim of this study was to to determine its prevalence in Casal de Quintanelas farm from the 16th of June to the 6th of November 2018, to verify if the entry or exit of positive animals to the milk tank caused any alteration in the level of antibodies in the milk tank, if the animals had different values in the antibodies at different stages of production and whether there was a positive correlation between mothers and daughters. For this, blood serum (98 samples) and individual (623 samples) or tank milk samples (22 samples) were used to perform the ELISA CIVTEST BOVIS NEOSPORA - HIPRA. The prevalence of Neospora caninum was 27.1% in a total of 461 female bovines, which is close to or within the ranges previously studied in our country. Of 181 cows analyzed, 21% seroconverted, becoming positive at the end of gestation (negative lactation and drying phase IRPC values and positive at calving). Although there was a change in the antibodies value with the entry or exit of animals to the milk tank, a statistically significant association between this and the proportion of positive animals in each tank was not detected. It was observed that the transmission is mostly vertical because more than 50% of positive mothers had positive daughters. The lack of association between mothers and daughters’ status and the existence of positive daughters from negative mothers indicated that there was also horizontal transmission on the farm. A uniform distribution of seropositive animals among age groups was also observed. The relative frequency of abortions was not considered normal (2,6%) and should be considered important and measures to reduce it should be taken, such as the adoption of infection preventive measures. In order to reduce or prevent bovine neosporosis on the farm, it was advised, whenever possible, and taking into account economic issues, the application of specific prevention and control measures for this disease.
Neospora caninum is a mandatory intracellular protozoan parasite that causes Bovine Neosporosis. It is a worldwide disease associated with abortions, involuntary culling of animals and decreased milk production, causing huge economic losses. The aim of this study was to to determine its prevalence in Casal de Quintanelas farm from the 16th of June to the 6th of November 2018, to verify if the entry or exit of positive animals to the milk tank caused any alteration in the level of antibodies in the milk tank, if the animals had different values in the antibodies at different stages of production and whether there was a positive correlation between mothers and daughters. For this, blood serum (98 samples) and individual (623 samples) or tank milk samples (22 samples) were used to perform the ELISA CIVTEST BOVIS NEOSPORA - HIPRA. The prevalence of Neospora caninum was 27.1% in a total of 461 female bovines, which is close to or within the ranges previously studied in our country. Of 181 cows analyzed, 21% seroconverted, becoming positive at the end of gestation (negative lactation and drying phase IRPC values and positive at calving). Although there was a change in the antibodies value with the entry or exit of animals to the milk tank, a statistically significant association between this and the proportion of positive animals in each tank was not detected. It was observed that the transmission is mostly vertical because more than 50% of positive mothers had positive daughters. The lack of association between mothers and daughters’ status and the existence of positive daughters from negative mothers indicated that there was also horizontal transmission on the farm. A uniform distribution of seropositive animals among age groups was also observed. The relative frequency of abortions was not considered normal (2,6%) and should be considered important and measures to reduce it should be taken, such as the adoption of infection preventive measures. In order to reduce or prevent bovine neosporosis on the farm, it was advised, whenever possible, and taking into account economic issues, the application of specific prevention and control measures for this disease.
Descrição
Orientação: Sofia Van Harten ; co-orientação: João Paisana
Palavras-chave
MESTRADO INTEGRADO EM MEDICINA VETERINÁRIA, VETERINÁRIA, BOVÍDEOS, GADO LEITEIRO, DOENÇAS PARASITÁRIAS, LEITE, ABORTOS, VETERINARY MEDICINE, BOVIDS, PARASITIC DISEASES, DAIRY CATTLE, MILK, BORTIONS, SERUM