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Bovine alphaherpesvirus 2 (BoHV-2) - the agent of bovine herpetic mamillitis (BHM) - is related to Human alphaherpesviruses 1 and 2 (HHV-1, HHV-2) and, as such, has been proposed as a model for vaccine and drug testing. We herein investigated the anti-viral activity in vitro against BoHV-2 of three anti-herpetic drugs: Cidofovir (CDV), Fanciclovir (FAM), Foscarnet (PFA), and diphenyl disselenide (Ph2Se2), a compound that has showed activity against HHV-2. Plaque reduction assays (PRA) revealed a significant reduction in viral plaques (p < 0.05) in cells treated with Ph2Se2 (79.7% reduction) or CDV (62.8%). FAM treatment resulted in a slight decrease in plaque number (22.9%, p < 0.05); PFA showed no activity. The effects of Ph2Se2 and CDV, alone or in combination, were investigated in ewes inoculated with BoHV-2 transdermally and submitted to daily topic treatment. Virus inoculated ewes developed lesions progressing through the stages of hyperemia, large papules or depressed dark areas, followed by scab formation. Treatment with Ph2Se2 resulted in reduction in clinical score from day 10 pi onwards (P < 0.05), shortening of clinical course and reduction in duration of virus shedding (P < 0.05) compared to untreated controls. Combined treatment (Ph2Se2 + CDV) and CDV alone, also led to clinical improvement (P < 0.05), yet less pronounced and delayed. These results are promising towards the use of Ph2Se2, alone or in combination with anti-herpetic drugs, in the treatment of udder and teat lesions produced by BoHV-2 in dairy cows.

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Bovine alphaherpesvirus 2 (BoHV-2) is the agent of herpetic mammilitis (BHM), a cutaneous and self-limiting disease affecting the udder and teats of cows. The pathogenesis of BoHV-2 is pourly understood, hampering the development of therapeutic drugs, vaccines and other control measures. This study investigated the pathogenesis of BoHV-2 in calves after inoculation through different routes. Three- to four-months seronegative calves were inoculated with BoHV-2 (107TCID50.mL-1) intramuscular (IM, n=4), intravenous (IV, n=4) or transdermal (TD) after mild scarification (n=4) and submitted to virological, clinical and serological monitoring. Calves inoculated by the IV route presented as light increase in body temperature between days 6 to 9 post-inoculation (pi). Virus inoculation by the TD route resulted in mild inflammatory lesions at the sites of inoculation, characterized by hyperemia, small vesicles, mild exudation and scab formation, between days 2 and 8pi. Virus or viral DNA was detected by PCR in the crusts/swabs collected from lesions of 3 out of 4 animals inoculated TD from day 2 to 8pi. Viremia was detected in 3/4 animals of the IM group (from day 4 to 8pi); in 2/4 animals of the IV group (days 6 and 8pi) but not in the TD group. Calves from all inoculated groups seroconverted to BoHV-2 in titers from 4 to 64, as indicated by virus-neutralizing (VN) assays performed in sera collected at day 15pi. Administration of dexamethasone (Dex) to the inoculated calves at day 48pi, did not result in virus reactivation as indicated by lack of virus detection in the blood and/or in inoculation sites and no increase in VN antibody titers. These results demonstrated that BoHV-2 was able to replicate efficiently in calves following different routes of exposure, produced viremia after IM and IV inoculation and was not reactivated by Dex treatment.(AU)

O alfaherpesvírus bovino 2 (BoHV-2) é um agente etiológico da mamilite herpética (BHM), uma doença cutânea e autolimitante do úbere e tetos de vacas. Pouco se sabe sobre a patogênese do BoHV-2, dificultando o desenvolvimento de medicamentos terapêuticos e vacinas. Este estudo investigou a patogênese do BoHV-2 em bezerros após a inoculação por diferentes vias. Bezerros soronegativos de três a quatro meses foram inoculados com BoHV-2 (107TCID50.mL-1) por via intramuscular (IM, n=4), por via intravenosa (IV, n=4) ou transdérmica (TD, n=4) após escarificação leve e submetidos a monitoramento virológico, clínico e sorológico. Os bezerros inoculados pela via IV apresentaram aumento leve da temperatura corporal entre os dias 6 a 9 pós-inoculação (pi). A inoculação do vírus pela via TD resultou em lesões inflamatórias leves nos locais de inoculação, caracterizadas por hiperemia, pequenas vesículas, exsudação leve e formação de crostas, entre os dias 2 e 8pi. O vírus ou DNA viral foi detectado por PCR nas crostas/swabs coletados de lesões de 3 de 4 animais inoculados TD do dia 2 ao 8pi. Viremia foi detectada em 3/4 dos animais do grupo IM (do dia 4 ao 8pi); em 2/4 animais do grupo IV (dias 6 e 8pi), mas não no grupo TD. Bezerros de todos os grupos inoculados soroconverteram o BoHV-2 em títulos de 4 a 64, conforme indicado por ensaios de vírus-neutralização (VN) realizados em soro coletado no dia 15pi. Administração de dexametasona (Dex) nos bezerros inoculados no dia 48pi, não resultou em reativação do vírus, como indicado pela falta de detecção de vírus no sangue e/ou nos locais de inoculação e pela ausência de aumento nos títulos de anticorpos. Estes resultados demonstraram que o BoHV-2 foi capaz de replicar eficientemente em bezerros seguindo diferentes vias de inoculação, produziu viremia após a inoculação IM e IV e não foi reativado pelo tratamento com Dex.(AU)

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Bovine alphaherpesvirus 2 (BoHV-2) is the agent of herpetic mammilitis (BHM), a cutaneous and self-limiting disease affecting the udder and teats of cows. The pathogenesis of BoHV-2 is pourly understood, hampering the development of therapeutic drugs, vaccines and other control measures. This study investigated the pathogenesis of BoHV-2 in calves after inoculation through different routes. Three- to four-months seronegative calves were inoculated with BoHV-2 (107TCID50.mL-1) intramuscular (IM, n=4), intravenous (IV, n=4) or transdermal (TD) after mild scarification (n=4) and submitted to virological, clinical and serological monitoring. Calves inoculated by the IV route presented as light increase in body temperature between days 6 to 9 post-inoculation (pi). Virus inoculation by the TD route resulted in mild inflammatory lesions at the sites of inoculation, characterized by hyperemia, small vesicles, mild exudation and scab formation, between days 2 and 8pi. Virus or viral DNA was detected by PCR in the crusts/swabs collected from lesions of 3 out of 4 animals inoculated TD from day 2 to 8pi. Viremia was detected in 3/4 animals of the IM group (from day 4 to 8pi); in 2/4 animals of the IV group (days 6 and 8pi) but not in the TD group. Calves from all inoculated groups seroconverted to BoHV-2 in titers from 4 to 64, as indicated by virus-neutralizing (VN) assays performed in sera collected at day 15pi. Administration of dexamethasone (Dex) to the inoculated calves at day 48pi, did not result in virus reactivation as indicated by lack of virus detection in the blood and/or in inoculation sites and no increase in VN antibody titers. These results demonstrated that BoHV-2 was able to replicate efficiently in calves following different routes of exposure, produced viremia after IM and IV inoculation and was not reactivated by Dex treatment.(AU)

O alfaherpesvírus bovino 2 (BoHV-2) é um agente etiológico da mamilite herpética (BHM), uma doença cutânea e autolimitante do úbere e tetos de vacas. Pouco se sabe sobre a patogênese do BoHV-2, dificultando o desenvolvimento de medicamentos terapêuticos e vacinas. Este estudo investigou a patogênese do BoHV-2 em bezerros após a inoculação por diferentes vias. Bezerros soronegativos de três a quatro meses foram inoculados com BoHV-2 (107TCID50.mL-1) por via intramuscular (IM, n=4), por via intravenosa (IV, n=4) ou transdérmica (TD, n=4) após escarificação leve e submetidos a monitoramento virológico, clínico e sorológico. Os bezerros inoculados pela via IV apresentaram aumento leve da temperatura corporal entre os dias 6 a 9 pós-inoculação (pi). A inoculação do vírus pela via TD resultou em lesões inflamatórias leves nos locais de inoculação, caracterizadas por hiperemia, pequenas vesículas, exsudação leve e formação de crostas, entre os dias 2 e 8pi. O vírus ou DNA viral foi detectado por PCR nas crostas/swabs coletados de lesões de 3 de 4 animais inoculados TD do dia 2 ao 8pi. Viremia foi detectada em 3/4 dos animais do grupo IM (do dia 4 ao 8pi); em 2/4 animais do grupo IV (dias 6 e 8pi), mas não no grupo TD. Bezerros de todos os grupos inoculados soroconverteram o BoHV-2 em títulos de 4 a 64, conforme indicado por ensaios de vírus-neutralização (VN) realizados em soro coletado no dia 15pi. Administração de dexametasona (Dex) nos bezerros inoculados no dia 48pi, não resultou em reativação do vírus, como indicado pela falta de detecção de vírus no sangue e/ou nos locais de inoculação e pela ausência de aumento nos títulos de anticorpos. Estes resultados demonstraram que o BoHV-2 foi capaz de replicar eficientemente em bezerros seguindo diferentes vias de inoculação, produziu viremia após a inoculação IM e IV e não foi reativado pelo tratamento com Dex.(AU)

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Teat papillomatosis is caused by different bovine papillomavirus (BPV) types and is especially important for dairy cows, because it results in severe damage to the health and structure of the mammary gland. This work describes the molecular and pathological aspects of teat papillomatosis in dairy cows in southern Brazil. Samples of teat papillomas were collect from 73 slaughtered dairy cows. Fragments of the lesions were collected in individual pools per animal and subjected to PCR using the FAP primer pair and sequencing of the amplification products. Teats with the remaining lesions were fixed in 10% neutral buffered formalin, routinely processed for histopathology, and stained with hematoxylin and eosin (H&E). Papillomatous lesions were characterized by three macroscopic patterns, namely exophytic (5 [6.9%]), flat (29 [39.7%]), and mixed (39 [53.4%]). Histologically, all samples were identified as squamous papillomas. Partial sequencing of the L1 gene resulted in the detection of 8 classical BPV types (BPVs 4, 6, 7, 8, 9, 10, 11, and 12) in 27 samples, 6 previously reported putative BPV types in 17 samples, and 10 putative new BPV types in 15 samples. Four sequences could not be classified, and 10 were negative in the PCR. There was no correlation between the gross pattern and the BPV type identified, and all the samples were characterized by squamous papillomas under histological examination. However, 24 different BPV types were identified, demonstrating high genetic diversity among BPVs associated with teat papillomatosis in dairy cows in southern Brazil.

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Background: Caprine Arthritis Encephalitis (CAE) is a disease that causes productive losses in dairy goat flocks due to thereduction in milk production, followed by lesions in joints and mammary glands. An early diagnosis is essential, consideringthat there is frequent occurrence of asymptomatic animals. Hence, this study aimed to perform a comparison of immunological and molecular based diagnostic tests, represented by Agar Gel Immunodiffusion (AGID), Western Blot (WB) andnested Polymerase Chain Reaction (nPCR). In addition, the mammary glands (MG) of dairy goats were clinically evaluated.Materials, Methods & Results: Blood collection and clinical examination were performed in 1191 dairy goats of 12 farms locatedin Northeastern and Southeastern regions of Brazil. Serological (AGID, WB) and molecular (nPCR) test results were comparedand the data, along with MG alterations, were analyzed using Epi-info 7 and WinEpiscope 2.0. Seroprevalence in AGID test was41.14% (490/1191). In WB, 51.47% (613/1191) of animals were seropositive and nPCR detected 69.44% (827/1191) positiveanimals. Hence, WB was more sensitive (P < 0.001) than AGID. However, nPCR detected more positive animals than AGID (P< 0.001) and WB (P < 0.001). The analysis of mammary glands revealed that 105 out of 1096 nanny goats presented alterations,of which 101 presented altered consistency, 16 presented elevated temperatures and 60 had enlarged retromammary lymph nodes.There was significant statistic difference (P < 0.05) only when comparing the results of serological tests with MG alterations.Discussion: In general, AGID technique is most frequently used when screening flocks for the disease due to the practicalityand low cost this test presents. However, the results demonstrated that AGID detected the lowest number of positive animals.This low sensitivity that the test presented may be attributed to its antigen-antibody interaction mechanism...(AU)

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Background: Caprine Arthritis Encephalitis (CAE) is a disease that causes productive losses in dairy goat flocks due to thereduction in milk production, followed by lesions in joints and mammary glands. An early diagnosis is essential, consideringthat there is frequent occurrence of asymptomatic animals. Hence, this study aimed to perform a comparison of immunological and molecular based diagnostic tests, represented by Agar Gel Immunodiffusion (AGID), Western Blot (WB) andnested Polymerase Chain Reaction (nPCR). In addition, the mammary glands (MG) of dairy goats were clinically evaluated.Materials, Methods & Results: Blood collection and clinical examination were performed in 1191 dairy goats of 12 farms locatedin Northeastern and Southeastern regions of Brazil. Serological (AGID, WB) and molecular (nPCR) test results were comparedand the data, along with MG alterations, were analyzed using Epi-info 7 and WinEpiscope 2.0. Seroprevalence in AGID test was41.14% (490/1191). In WB, 51.47% (613/1191) of animals were seropositive and nPCR detected 69.44% (827/1191) positiveanimals. Hence, WB was more sensitive (P < 0.001) than AGID. However, nPCR detected more positive animals than AGID (P< 0.001) and WB (P < 0.001). The analysis of mammary glands revealed that 105 out of 1096 nanny goats presented alterations,of which 101 presented altered consistency, 16 presented elevated temperatures and 60 had enlarged retromammary lymph nodes.There was significant statistic difference (P < 0.05) only when comparing the results of serological tests with MG alterations.Discussion: In general, AGID technique is most frequently used when screening flocks for the disease due to the practicalityand low cost this test presents. However, the results demonstrated that AGID detected the lowest number of positive animals.This low sensitivity that the test presented may be attributed to its antigen-antibody interaction mechanism...

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Teat papillomatosis affects dairy cows worldwide. Milking can become difficult due to teat warts, and maintaining affected cows in the herds may diminish economic profit in the dairy industry. Currently, 13 bovine papillomavirus (BPV) types have been fully characterized, and numerous putative BPV types have been identified through partial L1 gene PCR. In order to identify the viral types present in warts on the udders of dairy cows, 40 teat lesions from 24 cows from 13 cattle farms in three States of Brazil were evaluated by PV L1 gene PCR. The warts that were evaluated contained sequences from BPVs 6-10, the putative BPV types BAPV9 and BAPV4, and two unreported putative papillomavirus (PV) types, named BPV/BR-UEL6 and BPV/BR-UEL7. In addition, mixed infections and coinfections were identified, since more than one lesion was observed on the udders of 13 cows. Phylogenetic analysis showed that BPV/BR-UEL6 is closely related to BPVs belonging to the genus Xipapillomavirus, while BPV/BR-UEL7 clustered with the previously reported strains Cervus timorensis and Pudu puda PVs, which represent a putative new PV type, and it was only distantly related to xi-, epsilon-, delta- and dyoxi-PVs. These results provide information that will assist in the understanding of the association of BPVs 6, 7, 8, 9, and 10, as well as putative BPV types BAPV4 and BAPV9, with mammary papillomatosis. This is the first characterization of putative novel PV types BPV/BR-UEL6 and BPV/BR-UEL7 in teat warts of dairy cows, highlighting the high genetic diversity of BPVs associated with teat papillomatosis.

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Vaccinia virus (VACV) is the etiological agent of bovine vaccinia (BV), an important zoonosis that affects dairy cattle. There are many aspects of the disease that remain unknown, and aiming to answer some of these questions, the clinical, hematological, and biochemical parameters of VACV experimentally infected cows were evaluated. In the first part of the study, lactating cows were infected with VACV-GP2 strain. In the second part, animals previously infected with VACV-GP2 were divided into two treatment groups: Group 1, immunosuppressed cows; and Group 2, re-infected cows. In this study, BV could be experimentally reproduced, with similar lesions as observed in natural infections. Moreover, a short incubation period and local lymphadenopathy were also observed. VACV could be detected by PCR and isolated from scabs taken from teat lesions of all inoculated and re-inoculated animals. Lymphocytosis and neutrophilia were observed in all animals from the first part of the experiment, and lymphopenia and relative neutrophilia were observed in the immunosuppressed animals. Detection of viral DNA in oral mucosa lesions suggests that viral reactivation might occur in immunosuppressed animals. Moreover, clinical disease with teat lesions may occur in previously VACV-infected cows under the experimental conditions of the present study.

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Bovine vaccinia (BV) is a zoonosis caused by Vaccinia virus (VACV) that affects dairy cattle and milkers, causing economic losses and impacting animal and human health. Based on the clinical presentation, BV appears to be a localized disease, with lesions restricted to the skin of affected individuals. However, there are no studies on the pathogenesis of the disease in cows to determine if there is a systemic spread of the virus and if there are different ways of VACV shedding. The objective of this work was to study if there is a systemic spread of VACV in experimentally infected cows and to study the kinetics of VACV circulation in the blood and shedding in the feces of these animals. To this end, eight crossbred lactating cows were used. Three teats of each cow were inoculated with the GP2V strain of VACV. All animals were monitored daily, and blood and fecal samples were collected for 67 days post-infection (dpi). After this period, four of these previously infected cows were immunosuppressed using dexamethasone. Viral DNA was continuously detected and quantified in the blood and feces of these animals in an intermittent way, even after the resolution of the lesions. At slaughter, tissues were collected, and viral DNA was detected and quantified in the mesenteric and retromammary lymph nodes, ileum, spleen and liver. The detection of VACV DNA in the feces for a longer period (67 dpi) and in the lymphatic organs provides new evidence about VACV elimination and suggests that BV could be a systemic infection with a chronic course and viral shedding through the feces.

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A Artrite Encefalite Caprina (AEC) é uma lentivirose multisistêmica que tem a glândula mamária caprina como um dos alvos lesionais da doença. Pode causar uma manifestação mamária específica, chamada de mastite endurativa, além da mama representar uma importante via de eliminação do vírus, mesmo em animais que não apresentam a forma clínica. Considerando-se a possibilidade desta virose, cuja célula alvo predominante é o monócito, levar a alterações imunológicas que influenciem a susceptibilidade do animal a outras doenças, objetivou-se avaliar essa interação do vírus e da imunidade do hospedeiro por meio de fenotipagem, fagocitose e produção de Espécies reativas de oxigênio (ERO) e dos mecanismos de morte das células sanguíneas e lácteas de cabras naturalmente infectadas. Para isso 200 cabras foram triadas e, destas selecionadas oito fêmeas não sororreagentes e dez sororreagentes na pesquisa de anticorpos séricos para AEC, dentro dos padrões hematológicos da espécie e com dois exames bacteriológicos do leite negativos. O leite e o sangue colhido destes animais foram submetidos às seguintes provas: fenotipagem dos leucócitos CD4+, CD8+, CD14+, PG68A+ e CD45+, fagocitose de Staphylococcus aureus e de Escherichia coli por células CD14+ e PG68A+, produção de ERO e marcação com Anexina-V e Iodeto de Propídeo (PI) por granulócitos e células mononucleares. A infecção pelo VAEC pode ser associada a um aumento de células CD14+ no leite, mas não no sangue. Os outros perfis celulares não sofreram alterações. Quanto a função fagocítica, o vírus reduziu a porcentagem de fagocitose de Staphylococcus aureus por granulócitos PG68A+ do leite. Esta alteração não ocorreu na fagocitose de Escherichia coli e na produção de ERO dessas células, nem na fagocitose e produção de ERO pelas células CD14+ ressaltando que nesses processos a espécie bacteriana pode sofrer interações com o vírus ou mesmo com a resposta imune do organismo infectado. O VAEC não influenciou significativamente os mecanismos de morte ora investigados, mas a tendência dos resultados sugere que possa haver indução de morte por apoptose e/ou por necrose nos granulócitos do sangue e influenciar no processo de necrose destas células no leite, sem alterar esses processos nas células mononucleares. Ressalta-se a importância da interação monócito-neutrófilo na glândula mamária, principalmente nos animais sororreagentes para AEC, mesmo na ausência de mastite bacteriana

The caprine arthritis encephalitis (CAE) is a multisystem lentivirose that have the goat mammary gland as one target of the lesional disease. May cause a mammary specific expression, called indurative mastitis, beyond these organ represent a major route of virus elimination, even in animals that do not exhibit this clinical manifestation. Considering the possibility of this virus, whose target cell are predominantly monocyte, lead to immunological changes that influence the animal's susceptibility to other diseases, this study aimed to evaluate the interaction of virus and host immunity by phenotyping, phagocytosis and production of reactive oxygen species (ROS) and the mechanisms of cell death, in blood and milk of goats naturally infected. For that, 200 goats were screened and was selected eight females non sero-reagents and ten seroreagents for serum antibodies against CAE, with the haematological analises within the species standards and two negative bacteriological tests of milk. Milk and blood from these animals underwent the following tests: phenotyping of leukocytes CD4+, CD8+, CD14+, PG68A+ and CD45+, phagocytosis of Staphylococcus aureus and Escherichia coli ROS production by CD14+ and PG68A+ cells, and labeling with Annexin-V and propidium iodide (PI) for granulocytes and mononuclear cells. CAEV infection may be associated with an increase in CD14+ cells in milk, but not in blood. The other cellular profile did not change. In the phagocytic function, the virus reduced the percentage of phagocytosis of Staphylococcus aureus by granulocytes PG68A+ milk. This change did not occur in the phagocytosis of Escherichia coli and production of ROS in these cells, nor in phagocytosis and ROS production by CD14+ cells, noting that in those cases the bacterial species may undergo interactions with the virus or even with the immune response of the infected organism. The VAEC not significantly affect the mechanism of death now investigated, but the tendency of the results suggests that can induce apoptosis and/or necrosis in the blood granulocytes and influence the process of necrosis of these cells in milk, without changing these processes mononuclear cells. We emphasize the importance of monocyte-neutrophil interaction in the mammary gland, especially in animals seropositive for CAE, even in the absence of bacterial mastitis

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