Is Bluetongue Virus a Risk Factor for Reproductive Failure in Tropical Hair Sheep in Brazil?

Background: Bluetongue is a vector-borne viral disease transmitted by midges from the genus Culicoides. The disease can infect most of the ruminant and camelid species, but the severe disease is most often seen in european wool and mutton sheep breeds. In this sense, there is a gap in the knowledge on BTV infection in hair sheep breeds from tropical zones. Thus, this study aimed at establishing whether exposure to BTV is a risk factor for reproductive failure in Santa Inês ewes, a hair sheep breed, reared under tropical conditions in Brazil.Materials, Methods & Results: A retrospective cross-sectional study was carried out in sheep farms in São Paulo state, Brazil, after the rainy season. Serum samples from 110 Santa Inês ewes with a history of reproductive disorders, in the last 6 months, which were included: abortion, premature birth, stillbirth, retention of placenta, infertility, estrus repetition, fetal malformation, weak lamb birth and neonatal death were collected. The presence of antibodies against BTV was assessed by agar gel immunodiffusion method (AGID). Serology to the infectious agents Brucela ovis, Lepstopira spp., Toxoplasma gondii, Neospora caninum and Campylobacter sp. were also assessed. Bivariate associations between the outcome and individual explanatory variables were assessed using the Fisher's exact test. Abortion was the most common reproductive disorder (53%; 74/139) observed, followed by estrus repetition (12%; 17/139) and infertility (11%; 15/139). Other disorders related to the conceptus totaled nearly one fourth of the reported disorders. A total of 20% (22/110) of the ewes were seropositive to BTV. A higher frequency of BTV seropositive than BTV seronegative ewes with a history of abortion was found. Also, abortion with seroreactivity to BTV was tested for prevalence ratio that showed 1.38 [95% CI 1.10-1.74; P = 0.030]. With regards to the abortion involvement of other infectious diseases associated with the seropositive ewes to BTV, more than a half of ewes (53%; 10/19) were solely seropositive for BTV.Discussion: In the current study, it was detected 20% (22/110) of seropositive ewes to BTV. These findings demonstrated that even though the BTV has been considered endemic in tropical countries such as Brazil, there are regions or microclimates in which the virus cannot be present or in varied prevalence. The history of abortion was identified as the potential factor associated with BTV seropositivity in Santa Ines ewes. Equally, the differential diagnosis for other infectious agents related to abortion demonstrated the unique presence of antibodies against BTV in more than half of all cases. Other studies with native sheep flocks in Iran and Nepal also demonstrated a strong positive correlation between abortion history and seropositivity for BTV. Thus, it is possible that in other continents of the world, under tropical conditions, the virus does not behave the same asymptomatic infection such as have been reported for native sheep breeds in Africa. In conclusion, it was demonstrated that one-fifth animals were positive for antibodies against BTV clearly implying the viral spreading in the local hair sheep flocks. These findings highlight the importance of surveillance related to BTV in endemic areas. Therefore, it is recommended to strengthen the surveillance system for BTV within Brazil and to educate farmers about the management and control of this disease. 

Prevalência de anticorpos contra o vírus da língua azul em ovinos do Distrito Federal

The aims of the present study were to determine the prevalence of bluetongue virus antibodies in sheep from Distrito Federal. Sera from 606 sheep of 18 herds were submitted to the agar-gel immunodiffusion for bluetongue virus antibodies. The prevalences of bluetongue infection found in Distrito Federal were 100% (CI 95%: 84.67 to 100.00) for flocks and 52.37% (389/606) (CI 95%: 35.76 to 68.98) for animals. Thus, data from the present study showed that infection by bluetongue virus is highly widespread in sheep flocks in the Distrito Federal, which intensifies the need for assessments on the impact of this disease in Brazil. ________________________________________________________________________________________________________ RESUMOO objetivo deste trabalho foi estimar a prevalência de anticorpos contra o vírus da língua azul (BTV) em rebanhos ovinos do Distrito Federal. Soros de 606 ovinos, pertencentes a 18 propriedades, foram analisados pela técnica de imunodifusão em ágar gel (AGID), para pesquisa de anticorpos contra o BTV. As prevalências de rebanhos e de animais infectados pelo vírus da língua azul no Distrito Federal foram respectivamente de 100% (IC 95%: 84,67% a 100%) e de 52,37% (389/606) (IC 95%: 35,76% a 68,98%). Assim, o presente estudo permite concluir que o vírus da língua azul está amplamente disseminada no rebanho ovino do Distrito Federal

Genome sequence of Bluetongue virus serotype 17 isolated in Brazil in 2014

The complete genome sequence of Bluetongue virus (BTV) serotype 17 strain 17/BRA/2014/73, isolated from a sheep in Brazil in 2014, is reported here. All segments clustered with western topotype strains and indicated reassortment events with other BTV from the Americas. The strain 17/BRA/2014/73 represents a novel reference strain for BTV-17 from South America

INFECÇÃO SIMULTÂNEA PELO VÍRUS DA DIARRÉIA BOVINA A VÍRUS EBABESIA BOVIS EM BEZERRA RECÉM-NASCIDA

Neste texto relata-se o caso de uma bezerra recém-nascida que apresentava lesões nas córneas, focinho, narina e vulva quando foi encaminhada ao Hospital Veterinário da Escola de Veterinária da Universidade Federal de Minas Gerais (EV-UFMG). O diagnóstico foi de infecção simultânea pelo vírus da diarréia bovina a vírus e por Babesia bovis. PALAVRAS-CHAVE: Vírus da diarréia bovina a vírus, bezerra recém-nascida, Babesia bovis

Antimicrobial resistance in bacteria isolated from pigs with respiratory clinical signs in Brazil

A resistência antimicrobiana é uma questão atual e muito importante para a saúde pública, geralmente associada ao uso indiscriminado de antimicrobianos na produção animal. Diante disso, foi investigado o perfil de sensibilidade-antimicrobiana em isolados bacterianos de suínos com sinais clínicos respiratórios no Brasil. Foram estudadas 96 isolados provenientes de 51 granjas de suínos do Brasil. O método de disco-difusão foi empregado usando 14 antimicrobianos: amoxicilina, penicilina, ceftiofur, ciprofloxacina, enrofloxacina, clortetraciclina, doxiciclina, oxitetraciclina, tetraciclina, eritromicina, tilmicosina, florfenicol,lincomicina e sulfadiazina/trimetoprim. Streptococcus suis e Bordetella bronchiseptica foram os patógenos que apresentaram maiores níveis de resistência. Haemophilus parasuis apresentou altos níveis de resistência à sulfadiazina/trimetoprim (9/18=50%). Observou-se que isolados das regiões Centro-Oeste e Sul apresentaram quatro vezes mais chance de serem multirresistentes do que os isolados da região Sudeste. A maioria foi resistente a pelo menos um agente antimicrobiano (98,75%; 158/160) e 31,25% (50/160) das estirpes isoladas eram multirresistentes. No geral, os resultados do presente estudo mostraram grande nívelde resistência à lincomicina, eritromicina, sulfadiazina/trimetoprim e tetraciclina entre patógenos respiratórios bacterianos isolados de suínos no Brasil. Os altos níveis de resistência antimicrobiana em patógenos bacterianos respiratórios em suínos reforçam a necessidade do uso criterioso de antimicrobianos na suinocultura brasileira.Antimicrobial resistance is a current and important issue to public health, and it is usually associated with the indiscriminate use of antimicrobials in animal production. This study aimed to evaluate the antimicrobial susceptibility profile in bacterial isolates from pigs with clinical respiratory signs in Brazil. One hundred sixty bacterial strains isolated from pigs from 51 pig farms in Brazil were studied. In vitro disk-diffusion method was employed using 14 antimicrobial agents: amoxicillin, penicillin, ceftiofur, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, oxytetracycline, tetracycline, erythromycin, tilmicosin, florfenicol, lincomycin, and sulfadiazine/trimethoprim. The majority of isolates were resistant to at least one antimicrobial agent (98.75%; 158/160), while 31.25% (50/160) of the strains were multidrug resistant. Streptococcus suis and Bordetella bronchiseptica were the pathogens that showed higher resistance levels. Haemophilus parasuis showed high resistance levels to sulfadiazine/trimethoprim (9/18=50%). We observed that isolates from the midwestern and southern regions exhibited four times greater chance of being multidrug resistant than the isolates from the southeastern region studied. Overall, the results of the present study showed a great level of resistance to lincomycin, erythromycin, sulfadiazine/trimethoprim, and tetracycline among bacterial respiratory pathogens isolated from pigs in Brazil. The high levels of antimicrobial resistance in swine respiratory bacterial pathogens highlight the need for the proper use of antimicrobials in Brazilian pig farms

Diagnoses of Ovine Infection by the Serotype-4 Bluetongue Virus on Minas Gerais, Brazil

Background: Bluetongue (BT) is a viral disease transmitted by hematophagous vectors of the genus Culicoides. In Brazil, the identifcation of antibodies against the virus has been held for over thirty years, however clinicopathological diagnosis of the disease are scarce. The frst reported case occurred in the state of Paraná in 2001, confrmed by isolation and identifcation of serotype 12 of BTV. In the state of Rio Grande do Sul, in 2009, two outbreaks confrmed and was identifed the serotype 12. Serotype 4 was isolated during an outbreak in the state of Rio de Janeiro in 2013. This study describes the Diagnoses of ovine infection by the serotype-4 bluetongue virus in Minas Gerais, Brazil. Case: In a farm in the Southern region of the state of Minas Gerais, a group of 28 male sheep, was sent for necropsy at the Setor de Patologia Veterinária of Universidade Federal de Lavras (SPV-UFLA). In a flock of 80 male sheep 28 died with clinical signs of respiratory distress, whereas other showed signs of anemia and hypoproteinemia, cough, sneezing, prostration, fever, mucopurulent nasal discharge, anemia and submandibular edema. At necropsy, the main changes observed were cranioventral pulmonary consolidation, hemorrhage at the base of the pulmonary artery and ulcerating lesions in the hard palate mucosa, rumen and reticulum. The histological changes consisted of bacterial bronchopneumonia, papillary necrosis associated with bacterial structures, multifocal vasculitis in the submucosa and thrombi in blood vessels of the serosa in the rumen and reticulum, hyaline and flocculate necrosis in esophageal muscle, skeletal and cardiac muscle fbers were also observed, associated with moderate mononuclear inflammatory infltrate between fbers and around blood vessels. Discussion: The diagnosis of BT was confrmed by the identifcation of nucleic acids of the virus in blood samples and from tissues of animals from the herd by RT-PCR and by the detection of antibodies against Bluetongue virus with the agar gel immunodiffusion (AGID) test using serum samples from the remaining herd animals. Serotype 4 was identifed in three of the samples inoculated into KC cells. The hemorrhage at the base of the pulmonary artery, one characteristic fndings, was found in three of the necropsied sheep. The pulmonary lesions observed in the present study strongly suggest the occurrence of pneumonia caused by opportunistic bacteria, especially Mannheimia haemolytica, which is commonly associated with pneumonia in sheep infected with BTV. This work is the frst in the state of Minas Gerais and the fourth in Brazil to report an outbreak of the disease with clinical signs. The economic impact of bluetongue results not only from the direct losses of animals to the disease, but also to the correlation among BTV infection and other problems including pneumonia, abortion and verminoses. In a study focused on the characteristics of ovine farming in Minas Gerais, farmers from the center-southwest reported that abortion and pneumonia were among their main problems. Thus, further epidemiological studies on BTV may improve the level of identifcation of infected herds and may help promote prophylactic measures. Necropsies and histopathology exams constitute crucial tools for diagnosis, because most cases present at a sub-clinical stage or in association with other, concomitant diseases. Keywords: BTV 4, viral diseases, sheep, RT-PCR e IDG

Genome sequence of Bluetongue virus serotype 17 isolated in Brazil in 2014

The complete genome sequence of Bluetongue virus (BTV) serotype 17 strain 17/BRA/2014/73, isolated from a sheep in Brazil in 2014, is reported here. All segments clustered with western topotype strains and indicated reassortment events with other BTV from the Americas. The strain 17/BRA/2014/73 represents a novel reference strain for BTV-17 from South America

Virulence in Murine Model Shows the Existence of Two Distinct Populations of Brazilian Vaccinia virus Strains

Brazilian Vaccinia virus had been isolated from sentinel mice, rodents and recently from humans, cows and calves during outbreaks on dairy farms in several rural areas in Brazil, leading to high economic and social impact. Some phylogenetic studies have demonstrated the existence of two different populations of Brazilian Vaccinia virus strains circulating in nature, but little is known about their biological characteristics. Therefore, our goal was to study the virulence pattern of seven Brazilian Vaccinia virus strains. Infected BALB/c mice were monitored for morbidity, mortality and viral replication in organs as trachea, lungs, heart, kidneys, liver, brain and spleen. Based on the virulence potential, the Brazilian Vaccinia virus strains were grouped into two groups. One group contained GP1V, VBH, SAV and BAV which caused disease and death in infected mice and the second one included ARAV, GP2V and PSTV which did not cause any clinical signals or death in infected BALB/c mice. The subdivision of Brazilian Vaccinia virus strains into two groups is in agreement with previous genetic studies. Those data reinforce the existence of different populations circulating in Brazil regarding the genetic and virulence characteristics