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1.
Genome Announc ; 4(1)2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26823583

RESUMO

A complete genomic sequence of porcine parvovirus 2 (PPV-2) was detected by viral metagenome analysis on swine sera. A phylogenetic analysis of this genome reveals that it is highly similar to previously reported North American PPV-2 genomes. The complete PPV-2 sequence is 5,426 nucleotides long.

2.
Theriogenology ; 75(6): 1139-45, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21247624

RESUMO

Bovine herpesvirus 1 (BoHV-1) and 5 (BoHV-5) are important pathogens of the respiratory and genital tract of cattle and may also affect the central nervous system and cause meningoencephalitis. Both virus types are estimated to be widely distributed in Southern Brazil. In the present study, BoHV-1 and/or BoHV-5 DNA were detected in bovine semen samples from two states of Brazil by two species-specific nested polymerase chain reactions (nPCRs). These nPCRs were used to assay 53 samples of fresh semen and 23 samples of frozen semen from breeding bulls. Viral DNA was detected in all 76 semen samples: all were positive for BoHV-5, whereas 34 of these were positive for BoHV-1 as well. Moreover, in five fresh and in 13 frozen semen samples-of a total number of 40 samples suitable for virus isolation-infectious BoHV-1 and/or BoHV-5 virus were detected. In conclusion, that both BoHV-1 and BoHV-5 were detected in bovine semen in Brazil highlighted the importance of examining bull semen in search for both agents to reduce the risk of transmitting these viruses.


Assuntos
Doenças dos Bovinos/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/isolamento & purificação , Herpesvirus Bovino 5/isolamento & purificação , Sêmen/virologia , Animais , Brasil , Bovinos , Doenças dos Bovinos/epidemiologia , DNA Viral/química , Infecções por Herpesviridae/epidemiologia , Masculino
3.
Vet Microbiol ; 148(1): 18-26, 2011 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-20828945

RESUMO

Bovine herpesvirus type 5 (BoHV-5) is the causative agent of bovine herpetic encephalitis. In countries where BoHV-5 is prevalent, attempts to vaccinate cattle to prevent clinical signs from BoHV-5-induced disease have relied essentially on vaccination with BoHV-1 vaccines. However, such practice has been shown not to confer full protection to BoHV-5 challenge. In the present study, an inactivated, oil adjuvanted vaccine prepared with a recombinant BoHV-5 from which the genes coding for glycoprotein I (gI), glycoprotein E (gE) and membrane protein US9 were deleted (BoHV-5 gI/gE/US9(-)), was evaluated in cattle in a vaccination/challenge experiment. The vaccine was prepared from a virus suspension containing a pre-inactivation antigenic mass equivalent to 10(7.69) TCID(50)/dose. Three mL of the inactivated vaccine were administered subcutaneously to eight calves serologically negative for BoHV-5 (vaccinated group). Four other calves were mock-vaccinated with an equivalent preparation without viral antigens (control group). Both groups were boostered 28 days later. Neither clinical signs of disease nor adverse effects were observed during or after vaccination. A specific serological response, revealed by the development of neutralizing antibodies, was detected in all vaccinated animals after the first dose of vaccine, whereas control animals remained seronegative. Calves were subsequently challenged on day 77 post-vaccination (pv) with 10(9.25) TCID(50) of the wild-type BoHV-5 (parental strain EVI 88/95). After challenge, vaccinated cattle displayed mild signs of respiratory disease, whereas the control group developed respiratory disease and severe encephalitis, which led to culling of 2/4 calves. Searches for viral DNA in the central nervous system (CNS) of vaccinated calves indicated that wild-type BoHV-5 did not replicate, whereas in CNS tissues of calves on the control group, viral DNA was widely distributed. BoHV-5 shedding in nasal secretions was significantly lower in vaccinated calves than in the control group on days 2, 3, 4 and 6 post-challenge (pc). In addition, the duration of virus shedding was significantly shorter in the vaccinated (7 days) than in controls (12 days). Attempts to reactivate latent infection by administration of dexamethasone at 147 days pv led to recrudescence of mild signs of respiratory disease in both vaccinated and control groups. Infectious virus shedding in nasal secretions was detected at reactivation and was significantly lower in vaccinated cattle than in controls on days 11-13 post-reactivation (pr). It is concluded that the inactivated vaccine prepared with the BoHV-5 gI/gE/US9(-) recombinant was capable of conferring protection to encephalitis when vaccinated cattle were challenged with a large infectious dose of the parental wild type BoHV-5. However, it did not avoid the establishment of latency nor impeded dexamethasone-induced reactivation of the virus, despite a significant reduction in virus shedding after challenge and at reactivation on vaccinated calves.


Assuntos
Doenças dos Bovinos/prevenção & controle , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 5/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Formação de Anticorpos , Bovinos/imunologia , Doenças dos Bovinos/imunologia , Linhagem Celular , Encefalite Viral/imunologia , Encefalite Viral/prevenção & controle , Encefalite Viral/veterinária , Feminino , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/prevenção & controle , Herpesvirus Bovino 5/fisiologia , Masculino , Meningoencefalite/imunologia , Meningoencefalite/prevenção & controle , Meningoencefalite/veterinária , Testes de Neutralização , Vacinação/veterinária , Vacinas de Produtos Inativados/imunologia , Ativação Viral , Latência Viral , Eliminação de Partículas Virais
4.
Arq. bras. med. vet. zootec ; 61(supl.1): 27-34, nov. 2009. ilus, tab
Artigo em Português | LILACS | ID: lil-536299

RESUMO

Realizou-se um estudo para caracterizar a situação epidemiológica da brucelose no Estado de Goiás. O Estado foi estratificado em três circuitos produtores. Em cada circuito foram amostradas aleatoriamente 300 propriedades e, dentro dessas, foi escolhido de forma aleatória um número pré-estabelecido de animais, dos quais foi obtida uma amostra de sangue. No total, foram amostrados 10.744 animais, provenientes de 900 propriedades. Em cada propriedade visitada aplicou-se um questionário epidemiológico para verificar o tipo de exploração e as práticas de criação e sanitárias que poderiam estar associadas ao risco de infecção pela doença. O protocolo de testes utilizado foi o da triagem com o teste do antígeno acidificado tamponado e a confirmação dos positivos com o teste do 2-mercaptoetanol. O rebanho foi considerado positivo quando pelo menos um animal foi reagente às duas provas sorológicas. No estrato 1, a prevalência foi de 7,7 por cento [4,7-10,7 por cento] para propriedades, e de 1,4 por cento [0,99-1,7 por cento] para animais. No estrato 2, foi de 19,5 por cento [15,0-24,0 por cento] para propriedades e de 2,6 por cento [2,0-3,1 por cento] para animais. No estrato 3, foi de 21,4 por cento [16,7-26,1] para propriedades e 4,3 por cento [3,7-5,0 por cento] para animais. A prevalência obtida para o Estado foi de 17,5 por cento [14,9-20,2 por cento] para propriedades e de 3,0 por cento [2,7-3,3 por cento] para animais. Os fatores de risco (odds ratio, OR) associados à condição de foco, segundo a análise multivariada, foram: compra de reprodutores a comerciantes de gado (OR = 2,06 [1,12-3,52]), ocorrência de abortos nos últimos 12 meses (OR = 5,83 [3,86-8,8]) e prática de vacinação contra brucelose (OR = 2,07 [1,38-3,09]). Tanto a ocorrência de aborto quanto a vacinação são, neste caso, consequência da presença de brucelose no rebanho.


A study to characterize the epidemiological status of brucellosis in the State of Goiás was carried out. The State was divided in three regions. Three hundred herds were randomly sampled in each region and a pre-established number of animals was sampled in each of these herds. A total of 10,744 serum samples from 900 herds were collected. In each herd, it was applied an epidemiological questionnaire focused on herd traits as well as husbandry and sanitary practices that could be associated with the risk of infection. The serum samples were screened for antibodies against Brucella spp. by the Rose-Bengal Test (RBT), and all positive sera were re-tested by the 2-Mercaptoethanol test (2-ME). The herd was considered positive if at least one animal was positive on both RBT and 2-ME tests. For region 1, the herd prevalence was 7.7 percent [4.7-10.7 percent] and the animal prevalence was 1.4 percent [0.99-1.7 percent]. For region 2, the herd prevalence was 19.5 percent [15.0-24.0 percent] and the animal prevalence was 2.6 percent [2.0-3.1 percent]. For region 3, the herd prevalence was 21.4 percent [16.8-26.1 percent] and the animal prevalence was 4.3 percent [3.7-5.0 percent]. For the whole state, the herd prevalence was 17.5 percent [14.9-20.2 percent] and the animal prevalence was 3.0 percent [2.7-3.3 percent]. The multivariate analysis identified the following risk factors (odds ratio, OR) associated with positive herds: purchase of breeding stock from cattle traders (OR = 2.06 [1.12-3.52]), occurrence of abortions over the last 12 months (OR = 5.83 [3.86-8.8]), and vaccination against brucellosis (OR = 2.07 [1.38-3.09]). Both the abortions and the vaccination are, in this case, a consequence of the herd being infected with brucellosis.


Assuntos
Animais , Feminino , Bovinos , Aborto Animal/epidemiologia , Brucelose Bovina/epidemiologia , Brucelose Bovina/imunologia , Vacina contra Brucelose/administração & dosagem , Brasil/epidemiologia , Controle de Doenças Transmissíveis/métodos , Fatores de Risco , Rosa Bengala
5.
Arq. bras. med. vet. zootec ; 61(5): 1227-1229, out. 2009. tab
Artigo em Português | LILACS | ID: lil-532038

RESUMO

The serological status of porcine parvovirus (PPV) infection and transmissible gastroenteritis virus (TGEV) infection were determined in swine from extensive raising systems in the state of Goiás, Brazil. Ninety-seven serum samples were collected from animals in 12 extensive farms distributed in six cities located nearby Goiânia, GO, and 74 samples were collected from animals in a slaughterhouse in Goiânia, GO. For the PPV-specific antibody detection, the hemaglutination inhibition test (HI) was used; and for TGE antibody detection, the serum neutralization test was performed. Results showed that 25 out of the total 171 (14.4%) analyzed sera were positive for PPV antibodies, and the HI titers varied between 256 to 4,096. None of the 136 serum samples analyzed for TGEV was positive. This is probably the first study that detected PPV and TGEV-specific antibodies in swine herd in the state of Goiás. Data suggest that PPV but not TGEV circulated between and among this population of swine in that state.


Assuntos
Animais , Infecções por Parvoviridae/epidemiologia , Medidas de Ocorrência de Doenças , Parvovirus Suíno/isolamento & purificação , Suínos , Vírus da Gastroenterite Transmissível/isolamento & purificação , Brasil/epidemiologia , Infecções por Parvoviridae/mortalidade , Testes de Inibição da Hemaglutinação/métodos
6.
Trop Anim Health Prod ; 41(7): 1421-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19319656

RESUMO

In order to determine the role of Mycoplasma spp, Ureaplasma diversum and BHV-1 as causal agents of Granular Vulvovaginitis Syndrome in Nelore heifers raised under tropical conditions and based on the hypothesis that stressful conditions during puberty or breeding season would be a determinant factor for the infection, 340 heifers not vaccinated against BHV-1 were divided in Post-pubertal, in the beginning of the first breeding season, and Pubertal heifers. The vaginal lesion score (VLS) Grade 1 to 4 was giving according to lesion area and severity. Vaginal mucus was used to isolate Mycoplasma spp., Ureaplasma diversum and BHV-1. The predominant VLS was 2. No sample was positive for BHV-1; 48% were positive for Mycoplasma spp., Ureaplasma diversum, or both, with predominance of Ureaplasma diversum. Serum neutralization for BHV-1 showed more positive animals in pubertal group (23%); 3 of the paired sera demonstrated seroconversion. These data indicated that post-pubertal and pubertal Nelore heifers raised under extensive conditions are more susceptible to Mycoplasma spp. and Ureaplasma diversum. The hypothesis that the stress of pubertal period could lead to an acute vaginal infection by HBV-1 was not proofed.


Assuntos
Doenças dos Bovinos/etiologia , Herpesvirus Bovino 1 , Mycoplasma , Ureaplasma , Vagina/patologia , Vulvovaginite/veterinária , Animais , Brasil , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/patologia , Doenças dos Bovinos/virologia , Feminino , Testes de Neutralização/veterinária , Fatores de Risco , Estresse Fisiológico/fisiologia , Síndrome , Clima Tropical , Vagina/microbiologia , Vagina/virologia , Vulvovaginite/etiologia , Vulvovaginite/microbiologia , Vulvovaginite/patologia , Vulvovaginite/virologia
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