Síndrome da asfixia perinatal em potros / Perinatal asphyxia syndrome in foals

A neonatologia equina é um ramo crescente nos mercados veterinário brasileiro e mundial. Dentre as afecções que acometem o potro neonato, destaca-se a síndrome da asfixia perinatal, a qual é caracterizada por alterações neurológicas e comportamentais. Essa síndrome acomete o neonato desde o terço final da gestação até os 30 primeiros dias de vida. Apesar de ser descrita há décadas na literatura, esta síndrome ainda se caracteriza como um problema atual com relevante prevalência de óbitos. Tal ocorrência é, muitas vezes, devido à demora do diagnóstico e a falta de conhecimento agregado acerca de novos tratamentos mais efetivos, assim como tratamentos tradicionais de suporte. Assim, este trabalho teve como objetivo entender como ocorre à síndrome da asfixia perinatal em potros, identificar os sinais clínicos característicos, abordar tratamentos e divulgar informações que auxiliem na redução das taxas de óbito e de eutanásia dos potros acometidos. Para tal, o trabalho foi desenvolvido com base na revisão bibliográfica integrativa de literatura. O levantamento bibliográfico foi realizado por meio de consulta em base de dados, como Scielo, Google Acadêmico, Portal de Periódicos CAPES e PUBVET, tomando como referência, principalmente, a consulta à Biblioteca Virtual em Medicina Veterinária e Zootecnia (BVS Vet). O trabalho ainda focou na importância de agregar os tratamentos convencionais de suporte ao método alternativo de compressão, na intenção de elevar os índices de sucesso clínico dos potros neonatos acometidos e diminuir as ocorrências de eutanásias, comumente associadas ao alto custo médico aplicado ao animal acometido pela síndrome da asfixia perinatal.

Equine neonatology is an increasing segment in the Brazilian and global veterinary market. Among the disorders that affect the newborn foal, the perinatal asphyxia syndrome, which is characterized by neurological and behavioral changes, stands out. This syndrome affects the newborn from the last third of pregnancy until the first 30 days of life. Despite being described in the literature for decades, the syndrome is still characterized as a current problem with a relevant prevalence of deaths. This occurrence is, often, due to diagnostic delay and lack of aggregated knowledge about new and more effective treatments, as well as traditional supportive treatments. Thus, this study aimed to understand how perinatal asphyxia syndrome occurs in foals, identify the characteristical clinical signs, discuss treatments, and disseminate information that helps reduce the death and euthanasia rates of affected foals. For this purpose, this study was developed based on an integrative literature review. The bibliographic survey was carried out by consulting a database such as Scielo, Google Academic, Periodical's portal CAPES, and PUBVET, referring mainly to the consultation of the Virtual Library in Veterinary Medicine and Animal Science (BVS Vet). The work also focused on the importance of adding the supporting conventional treatments to the alternative squeeze method, intending to increase the clinical success rates of affected newborn foals and reduce the occurrence of euthanasia, commonly associated with the high medical care cost applied to the animal affected by perinatal asphyxia syndrome.

Antimicrobial susceptibility and pathogenicity of Escherichia coli strains of environmental origin / Suscetibilidade antimicrobiana e patogenicidade de amostras de Escherichia coli de origem ambiental

The study aimed to evaluate the antimicrobial susceptibility of 109 samples of Escherichia coli (E. coli) of environmental origin and to characterize these isolates according to the degree of pathogenicity in vivo, verifying a possible relationship between this variable and susceptibility to the active principles tested. The isolates were subjected to disc diffusion test to 14 antibiotics. From 16.5% to 90% of the samples were sensitive; 1 - 28.5% showed intermediate degree of susceptibility and between 9 to 78% of E. coli analyzed were resistant. The highest resistance percentages were seen in the class of quinolones and tetracyclines (>75%), and for sensitivity in the class of amphenicols (68.8%). By inoculating 1- day - old chicks, the isolates were classified as highly pathogenic (2.7%), intermediate (10.1%), low (42.2%) and apathogenic (45%). It was observed a wide variation in the susceptibility profile of isolates in relation to antimicrobials. It was also found that most of the samples had pathogenic potential (55%), thus being considered as APEC (avian pathogenic E. coli). No relationship between pathogenicity and antimicrobial susceptibility (P0.05) was observed.(AU)

O estudo teve como objetivo avaliar a suscetibilidade antimicrobiana de 109 amostras de Escherichia coli (E. coli) de origem ambiental frente a antibióticos e caracterizar esses isolados quanto ao grau de patogenicidade in vivo, verificando-se uma possível relação entre esta variável e a suscetibilidade aos princípios ativos testados. Os isolados foram submetidos ao teste de disco-difusão para 14 antibióticos. Entre 16.5% a 90% das amostras foram sensíveis, 1-28.5% apresentaram grau de suscetibilidade intermediário e entre 9-78% das E. coli analisadas foram resistentes. Os maiores percentuais de resistência foram encontrados para a classe das quinolonas e das tetraciclinas (>75%), e de sensibilidade para a classe dos anfenicóis (68.8%). Por meio da inoculação em pintinhos de um dia de idade, os isolados foram classificados como sendo de patogenicidade alta (2.7%), intermediária (10.1%), baixa (42.2%) e apatogênicos (45%). Foi observada uma ampla variação no perfil de suscetibilidade das amostras frente aos antimicrobianos. Verificou-se também que a maioria apresentou potencial patogênico (55%), sendo, portanto, consideradas APEC (E. coli patogênica para aves). Não foi observada relação entre a patogenicidade e a suscetibilidade aos antimicrobianos (P0.05).(AU)

Bovine herpesviruses do not play a major role in the differential diagnosis of rabies in cattle in southern Brazil

Background: Rabies has long been recognized as the major cause of encephalitis in cattle in Latin American countries. It has been estimated that nearly 50.000 cattle heads per year are lost due to encephalitis in that subcontinent, with a significant economic impact on cattle productive chains. In Brazil only, 2.500 to 3.000 cattle heads are estimated to be lost every year due to rabies. However, it is believed that rabies incidence in cattle is much larger, since usually only a few samples from affected animals in disease outbreaks are submitted to diagnostic laboratories. Rabies encephalitis is promptly and accurately diagnosed; however, particularly when rabies is excluded as causa mortis, the agent responsible for neurological disease of infectious origin often remains undetermined. Two bovine herpesviruses (BoHVs), bovine herpesvirus type 1 (BoHV-1) and bovine herpesvirus type 5 (BoHV-5) are major pathogens of cattle which are widely disseminated in Brazil. As usual in herpesvirus' biology, these tend to infect a large number of hosts and establish lifelong latent infections which may occasionally be reactivated. Both viruses, particularly BoHV-5, are often recovered from cases of neurological disease in cattle. The participation of BoHVs in the differential diagnosis of rabies must be evaluated. Besides, there might be associations between the occurrence of rabies and BoHV infections that deserve investigation. The aim of this study was to investigate whether bovine herpesvirus 1 and 5 would play a significant role in cases of neurological disease where rabies was the presumptive clinical diagnosis. In addition, associations between the occurrence of rabies and BoHV infections were searched for. The approach adopted for conducting such investigations was based on the search for viral nucleic acids as well as classical virus isolation on tissues of cattle submitted to rabies diagnosis over a two-year period, including rabies-positive and rabies-negative specimens. Materials, Methods & Results: Brain tissue samples of 101 cattle originally submitted to rabies diagnosis were collected over a two year period (2009-2010) from various municipalities within the state of Rio Grande do Sul, Brazil. Thirty nine of these samples had the diagnosis of rabies confirmed by standard laboratory diagnostic methods. Aliquots of tissues were submitted to DNA extraction and examined in search for genomes of bovine herpesviruses (BoHV) types 1 (BoHV-1) and 5 (BoHV-5) by as well as for infectious virus. Bovine herpesvirus genomes were detected in 78/101 (77.2%) samples, in which BoHV-1 genomes were detected in 26/78 (25.7%), BoHV-5 genomes in 22/78 (21.8%) and mixed BoHV infections (BoHV-1 and BoHV-5 genomes) were detected in 30/101 (29.7%) samples. In the 39 samples with confirmed rabies diagnosis, BoHV-1 DNA was detected in 9/39 (23%), BoHV-5 DNA in 6/39 (15.4%) and mixed infections with both BoHV types in 16/39 (41%) samples. However, no infectious herpesvirus was recovered from any of the specimens examined. Discussion: The high prevalence of BoHV1 and BoHV-5 infections was evidenced in the sampled population, but the absence of infectious BoHVs indicate that these were not associated to the occurrence of the cases of encephalitis where rabies was the primary suspicion. In addition, no association was detected between occurrence of rabies and detection of BoHVs, since the frequency of detection of herpesvirus genomes did not significantly differ between rabies-positive and rabies-negative samples. The detection of BoHV DNA in scattered areas of the brain with no infectious virus suggests that latency may take place in different regions of the brain.