Resultado da pesquisa (3)
Termo utilizado na pesquisa vacas prenhes
#1 - Osseous malformation in calves and its relationship with ingestion of apple pomace in pregnant cows
Abstract in English:
Three outbreaks of osseous malformation in claves born of cows fed apple pomace throughout pregnancy are described. This study was carried out from historical surveys on properties where apple pomace was used in cattle feeding. The outbreaks occurred in the municipalities of Lages, Santa Catarina state, from 2007 to 2012, and Ipê, Rio Grande do Sul state, from 2011 to 2012. These calves presented bone deformity characterized mainly by arthrogryposis and chondrodysplasia of the anterior limbs. At necropsy, the observed changes were restricted to bending and thickening of the anterior limbs and skull. Microscopically, a disorganized, irregular, misaligned hypertrophic zone was observed in the humeral‑radio-ulnar joints, in addition to absence of growth zone, thin bone trabeculae, and closed epiphyseal growth plate.
Abstract in Portuguese:
Descrevem-se 3 surtos de malformações ósseas em bezerros, nascidos de vacas prenhes alimentadas com bagaço de maçã. Estudos foram realizados a partir de levantamento de históricos em propriedades onde bagaço de maçã foi utilizado na alimentação de bovinos. Os surtos ocorreram nos municípios de Lages em Santa Catarina, de 2007 a 2012, e Ipê em Rio Grande do Sul, de 2011 a 2012. Dentre 20 e 69,2% dos bezerros apresentavam deformidade de membros, caracterizada principalmente por membros anteriores curvos e curtos. Na necropsia as alterações observadas restringiam-se ao encurvamento e engrossamento dos membros e do crânio. Microscopicamente nas articulações úmero-radio-ulnar, foi observado zona hipertrófica desorganizada, irregular e sem alinhamento, além de ausência da zona de crescimento e trabéculas ósseas finas e placa epifisária fechada.
#2 - Large luteal cell megalocytosis in pregnant cows with chronic seneciosis, 35(1):33-38
Abstract in English:
ABSTRACT.- Krabbe A.A., Gonçalves M.A., Pozzobon R., Pessoa C.R.M., Soares M.P., Costa R.A. & Anjos B.L. 2015. [Large luteal cell megalocytosis in pregnant cows with chronic seneciosis.] Megalocitose de células luteínicas grandes de vacas prenhes com seneciose crônica. Pesquisa Veterinária Brasileira 35(1):33-38. Laboratório de Patologia Veterinária, Universidade Federal do Pampa, Uruguaiana, RS 97500-970, Brazil. E-mail: anjosbl@gmail.com
Several species of Senecio are widely distributed on pasture lands in Southern Brazil. Farmers from this region are known to complain about declines in reproductive rates in cattl from undetermined causes. Several poisonous plants can cause direct and indirect reproductive disorders in cattle in several countries, including Brazil. However, their pathogenetic mechanisms are still poorly understood. The aim of this study is to describe ovarian lesions in cows with chronic seneciosis, from farms located in the Southwest Mesoregion of Rio Grande do Sul, a southern state in Brazil. Twenty-one cases of bovine chronic seneciosis diagnosed between 2011 and 2014 were analyzed. The study showed that chronic seneciosis is the major cause of death in adult cattle in the region. Four pregnant cows showing classical necropsy large luteal cells (LLG) from the ovaries of these four cows had marked megalocytosis and nuclear pseudo-inclusions. Some LLG showed nuclei with up to 23.69μm in diameter and the increase in size of these nuclei was significantly greater than measured those of control cows. It is concluded that the ingestion Senecio spp. induces ovarian changes in cows and the intoxication should be considered as a possible cause of reproductive failure in cattle herds from this region.
Abstract in Portuguese:
RESUMO.- Krabbe A.A., Gonçalves M.A., Pozzobon R., Pessoa C.R.M., Soares M.P., Costa R.A. & Anjos B.L. 2015. [Large luteal cell megalocytosis in pregnant cows with chronic seneciosis.] Megalocitose de células luteínicas grandes de vacas prenhes com seneciose crônica. Pesquisa Veterinária Brasileira 35(1):33-38. Laboratório de Patologia Veterinária, Universidade Federal do Pampa, Uruguaiana, RS 97500-970, Brazil. E-mail: anjosbl@gmail.com
Diversas espécies de Senecio estão amplamente difundidas nas pastagens de propriedades rurais do Sul do Brasil. Criadores dessa região relatam quedas nos índices reprodutivos dos rebanhos bovinos, muitas vezes de causas não determinadas. Várias plantas tóxicas são capazes de causar alterações reprodutivas diretas e indiretas em bovinos em diversos países, incluindo o Brasil, no entanto seus mecanismos patogenéticos ainda são pouco compreendidos. O objetivo desse trabalho é descrever lesões ovarianas em vacas com seneciose crônica proveniente de propriedades rurais da mesorregião Sudoeste Rio-grandense. Foram estudados 21 casos positivos de seneciose crônica diagnosticados entre 2011 e 2014. O estudo revelou que a seneciose crônica é a principal causa de morte de bovinos adultos na região. Quatro vacas prenhes apresentaram lesões hepáticas clássicas da intoxicação por Senecio spp. Essas vacas tiveram seus ovários avaliados histologicamente e células luteínicas grandes (CLG) desses ovários apresentavam megalocitose e pseudoinclusões nucleares. Algumas CLG apresentaram núcleos com até 23,69µm de diâmetro e o aumento no tamanho desses núcleos foi significativamente maior que os de vacas controle. Conclui-se que a intoxicação por Senecio spp. causa alterações ovarianas em vacas e é possível que a intoxicação cause perdas reprodutivas nos rebanhos bovinas da região.
#3 - Proteção fetal contra o vírus da diarréia viral bovina (BVDV) em vacas prenhes previamente imunizadas com uma vacina experimental atenuada, p.461-470
Abstract in English:
ABSTRACT.- Arenhart S., Silva L.F., Henzel A., Ferreira R., Weiblen R. & Flores E.F. 2008. [Fetal protection against bovine viral diarrhea virus (BVDV) in pregnant cows previously immunized with an experimental attenuated vaccine.] Proteção fetal contra o vírus da diarréia viral bovina (BVDV) em vacas prenhes previamente imunizadas com uma vacina experimental atenuada. Pesquisa Veterinária Brasileira 28(10):461-470. Departamento de Medicina Veterinária, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br
This paper reports the antibody response and fetal protection in pregnant cows conferred by an experimental vaccine containing two attenuated strains of bovine viral diarrhea virus (BVDV-1 and BVDV-2). Cows (n=19) were vaccinated twice, with a 34-days-interval, with the experimental vaccine and together with non-vaccinated controls (n=18), were mated and challenged between days 60 and 90 of gestation by intranasal inoculation of four heterologous BVDV-1 and BVDV-2 isolates. The antibody response was evaluated by serum-neutralization tests performed at different intervals after vaccination (days 34, 78 and 138 post-vaccination [pv]). Fetal protection was monitored by ultrassonographic and clinical examination of the dams and fetuses during the rest of gestation; and through virological and serological examination of pre-colostral blood obtained from aborted and/or recently born fetuses/calves. At the day of challenge (day 138 pv), all vaccinated cows had neutralizing antibodies in high titers against BVDV-1 (1,280- ³10,240), and with one exception (titer 20), presented moderate to high titers to BVDV-2 (80-1,280). At the end of the monitoring, only three out of 18 control cows (16.6%) delivered healthy, virus-free calves. Fifteen non-vaccinated cows (83.3%) presented signs of fetal infection and/or had reproductive losses. Seven of these cows (38.8%) delivered virus-positive calves; five were healthy and survived (27.7%); two were premature or weak and lasted three and 15 days, respectively. The other eight cows (44.4%) aborted between day 30 post-challenge and the parturition; or delivered premature or stillbirth calves. In contrast, 17 out of 19 (89.4%) vaccinated cows delivery virus-free, healthy calves. One vaccinated cow aborted around day 130 post-challenge, yet this fetus could not be examined for the presence of virus. Another cow delivered a virus-positive calf (5.2%). In summary, the experimental vaccine induced adequate antibody titers in most animals and the immunological response induced by vaccination was able to prevent fetal infection and reproductive losses upon challenge with a pool of heterologous BVDV isolates. Hence, this experimental vaccine may be an attractive alternative for the prevention of reproductive losses associated with BVDV infection.
Abstract in Portuguese:
ABSTRACT.- Arenhart S., Silva L.F., Henzel A., Ferreira R., Weiblen R. & Flores E.F. 2008. [Fetal protection against bovine viral diarrhea virus (BVDV) in pregnant cows previously immunized with an experimental attenuated vaccine.] Proteção fetal contra o vírus da diarréia viral bovina (BVDV) em vacas prenhes previamente imunizadas com uma vacina experimental atenuada. Pesquisa Veterinária Brasileira 28(10):461-470. Departamento de Medicina Veterinária, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br
This paper reports the antibody response and fetal protection in pregnant cows conferred by an experimental vaccine containing two attenuated strains of bovine viral diarrhea virus (BVDV-1 and BVDV-2). Cows (n=19) were vaccinated twice, with a 34-days-interval, with the experimental vaccine and together with non-vaccinated controls (n=18), were mated and challenged between days 60 and 90 of gestation by intranasal inoculation of four heterologous BVDV-1 and BVDV-2 isolates. The antibody response was evaluated by serum-neutralization tests performed at different intervals after vaccination (days 34, 78 and 138 post-vaccination [pv]). Fetal protection was monitored by ultrassonographic and clinical examination of the dams and fetuses during the rest of gestation; and through virological and serological examination of pre-colostral blood obtained from aborted and/or recently born fetuses/calves. At the day of challenge (day 138 pv), all vaccinated cows had neutralizing antibodies in high titers against BVDV-1 (1,280- ³10,240), and with one exception (titer 20), presented moderate to high titers to BVDV-2 (80-1,280). At the end of the monitoring, only three out of 18 control cows (16.6%) delivered healthy, virus-free calves. Fifteen non-vaccinated cows (83.3%) presented signs of fetal infection and/or had reproductive losses. Seven of these cows (38.8%) delivered virus-positive calves; five were healthy and survived (27.7%); two were premature or weak and lasted three and 15 days, respectively. The other eight cows (44.4%) aborted between day 30 post-challenge and the parturition; or delivered premature or stillbirth calves. In contrast, 17 out of 19 (89.4%) vaccinated cows delivery virus-free, healthy calves. One vaccinated cow aborted around day 130 post-challenge, yet this fetus could not be examined for the presence of virus. Another cow delivered a virus-positive calf (5.2%). In summary, the experimental vaccine induced adequate antibody titers in most animals and the immunological response induced by vaccination was able to prevent fetal infection and reproductive losses upon challenge with a pool of heterologous BVDV isolates. Hence, this experimental vaccine may be an attractive alternative for the prevention of reproductive losses associated with BVDV infection.
