Bacterial pneumonia in captive wild boars in southern Brazil: etiological and pathological causes

Respiratory diseases are one of the major health issues described in intensive pig production, causing important economic losses. However, there is little information on the prevalence, etiology and clinical-pathological presentation of these diseases in wild boars. For this reason, this work investigated the presence in captive wild boars of pneumonic lesions and bacterial pathogens commonly detected and associated with respiratory diseases in domestic pigs. A total of 226 captive wild boar lungs from two farms were examined in a slaughterhouse in Southern Brazil. The pneumonic lesions were classified as cranioventral, dorsocaudal, and disseminated, and the quantification of lesions was calculated. From the total of 226 lungs, 121 were collected for laboratory examination. Lungs with macroscopic lesions suggestive of pneumonia were collected for histological, bacteriological and molecular analysis. The molecular analysis was performed to detect the presence of Actinobacillus (A.) pleuropneumoniae, Glaesserella (G.) parasuis, Mycoplasma (M.) hyopneumoniae, Mycoplasma (M.) hyorhinis and Streptococcus (S.) suis serotype 2. The percentages of histological lesions and bacterial agents and their association were calculated. Cranioventral consolidation (75.2%) was the most prevalent macroscopic lung lesion, followed by disseminated (21.5%) and dorsocaudal (3.3%) distribution. Microscopically, chronic lesions were the most prevalent, representing 70.2% of the lungs. Moreover, BALT hyperplasia was present in 86.5% of the lungs, suppurative bronchopneumonia in 65.7%, and alveoli infiltrate in 46.8%. Six bacterial pathogens commonly described as agents of pig pneumonia were identified by bacterial or molecular methods: Pasteurella (P.) multocida, S. suis, M. hyopneumoniae, A. pleuropneumoniae, G. parasuis and M. hyorhinis. Twenty-eight different combinations of pathogens were identified in 84 samples (69.4%). The most common combinations were: M. hyopneumoniae and A. pleuropneumoniae (13.1%), M. hyopneumoniae, G. parasuis and M. hyorhinis (10.7%), and M. hyopneumoniae, A. pleuropneumoniae and G. parasuis (8.3%). Additionally, M. hyopneumoniae was the most frequent pathogen detected in this study, representing 58.7% of the samples. The detection of M. hyopneumoniae and M. hyorhinis by PCR was associated with the presence of BALT hyperplasia (P < 0.05) and there was also an association between the detection of M. hyopneumoniae by PCR and suppurative bronchopneumonia (P < 0.05). In addition, a significant association (P < 0.05) between the detection of M. hyopneumoniae and A. pleuropneumoniae by PCR and the histological classification (acute, subacute or chronic lesions) was observed. The results of this study were similar to those observed in slaughtered domestic pigs, although, the detection of opportunist pathogens was less frequent than that usually described in pig pneumonia. The high prevalence of pneumonia in captive wild boars at slaughter and the similar characteristics of pneumonia in captive wild boars and domestic pigs suggest that the close phylogenetic relationship between pigs and wild boars could influence the susceptibility of both species to the colonization of the same pathogens, indicating that captive wild boars raised in confined conditions could be predisposed to respiratory diseases, similar to domestic pigs.(AU)

Evaluation of data input in a rabies testing request form for herbivores / Avaliação da entrada de dados em um formulário de requisição de exame de raiva para herbívoros

Bovines and equines are the domestic animals with the highest incidence of rabies in Brazil. This study evaluated the data input in testing request forms for rabies in herbivores accompanying samples sent to a certified laboratory of rabies diagnosis in the state of Rio Grande do Sul, Brazil. Information was obtained systematically from all forms sent to the laboratory in 2013 and 2014 using a collection instrument that listed variables about the kind of form used, municipality of origin, description of the suspected animal, clinical signs, sample collection, and conservation procedure. The 11 most relevant variables (municipality of origin, geographic coordinates, species, gender, breed, age, herd size, clinical signs, persistence of clinical signs, biological material, and sample conservation) were assessed for the quality of the data entered, and percentage data input was calculated per form. In total, 603 forms were sent to the laboratory. The most used form was the FORM SN, (82.0%, 497/603). "Excellent" and "good" data inputs were observed only for one variable describing the location of suspected rabies cases or outbreaks and animals (species, gender, biological material). Quality of data input of variables describing geographic coordinates, age, breed, herd size, clinical signs, persistence of signs, and sample conservation method varied between "average" and "poor". The data input in testing request forms for herbivores are not dully supplied in suspected cases neurological syndromes, pointing to the need to increase awareness and improve training of field staff.(AU)

Bovinos e equinos são os animais domésticos com maior incidência de raiva no Brasil. Este estudo avaliou formulários de solicitação de testes para raiva em herbívoros acompanhando amostras enviadas a um laboratório certificado de diagnóstico de raiva no estado do Rio Grande do Sul, Brasil. As informações foram obtidas sistematicamente de todos os formulários enviados ao laboratório em 2013 e 2014 utilizando um instrumento de coleta que selecionou variáveis sobre o tipo de formulário utilizado, município de origem, descrição do animal suspeito, sinais clínicos, coleta de amostra e procedimento de conservação. As 11 variáveis mais relevantes (município de origem, coordenadas geográficas, espécie, gênero, raça, idade, tamanho do rebanho, sinais clínicos, persistência de sinais clínicos, material biológico e conservação da amostra) foram avaliadas quanto à qualidade dos dados inseridos, e os dados percentuais foram calculados por formulário. No total, 603 formulários foram enviados para o laboratório. O formulário mais utilizado foi o FORM SN, (82,0%, 497/603). Dados classificados como "excelentes" e "bons" foram observados apenas para uma variável que descreve a localização de casos suspeitos de raiva ou surtos e animais (espécie, gênero, material biológico). A qualidade da entrada dos dados das variáveis que descrevem coordenadas geográficas, idade, raça, tamanho do rebanho, sinais clínicos, persistência de sinais e método de conservação da amostra variou entre "regular" e "ruim". A qualidade dos dados dos formulários de solicitação de testes para herbívoros não foi devidamente fornecida em casos suspeitos de síndromes neurológicas, apontando para a necessidade de aumentar a conscientização e melhorar o treinamento do pessoal de campo.(AU)

Polimorfismos de nucleotídeos únicos em 15 códons do gene da proteína priônica em um rebanho Suffolk afetado com scrapie no Brasil / Single nucleotide polymorphisms at 15 codons of the prion protein gene from a scrapie-affected herd of Suffolk sheep in Brazil

Scrapie is a transmissible spongiform encephalopathy of sheeps and goats, associated with the deposition of a isoform of the prion protein (PrPsc). This isoform presents an altered conformation that leads to aggregation in the host's central nervous and lymphoreticular systems. Predisposition to the prion agent infection can be influenced by specific genotypes related to mutations in amino acids of the PrPsc gene. The most characterized mutations occur at codons 136, 154 and 171, with genotypes VRQ being the most susceptible and ARR the most resistant. In this study we have analyzed polymorphisms in 15 different codons of the PrPsc gene in sheeps from a Suffolk herd from Brazil affected by an outbreak of classical scrapie. Amplicons from the PrPsc gene, encompassing the most relevant altered codons in the protein, were sequenced in order to determine each animal's genotype. We have found polymorphisms at 3 of the 15 analyzed codons (136, 143 and 171). The most variable codon was 171, where all described alleles were identified. A rare polymorphism was found at the 143 codon in 4 percent of the samples analyzed, which has been described as increasing scrapie resistance in otherwise susceptible animals. No other polymorphisms were detected in the remaining 12 analyzed codons, all of them corresponding to the wild-type prion protein. Regarding the risk degree of developing scrapie, most of the animals (96 percent) had genotypes corresponding to risk groups 1 to 3 (very low to moderate), with only 4 percent in the higher risks group. Our data is discussed in relation to preventive measures involving genotyping and positive selection to control the disease.

Scrapie é uma encefalopatia espongiforme transmissível de ovinos e caprinos, associado a deposição da isoforma da proteína priônica (PrPsc). Essa isoforma apresenta uma alteração conformacional que leva ao acúmulo da proteína no sistema nervoso central e linforeticular do hospedeiro. A predisposição a infecção pelo agente priônico pode ser influenciado por genótipos específicos relacionados a mutações na sequência de aminoácidos do gene PrPsc. As principais mutações caracterizadas ocorrem nos códons 136, 154 e 171, sendo o genótipo VRQ o mais suscetível e o genótipo ARR o mais resistente. Nesse estudo nós analisamos os polimorfismos de 15 códons diferentes da gene PrPsc em ovinos de um rebanho da raça Suffolk no Brasil afetado com scrapie clássico. Os amplicons do gene da PrPsc, que contem os códons mais frequentemente encontrados foram sequenciados para determinar o genótipo de cada animal. Nós encontramos 3 polimorfismos do 15 códons analisados (136, 143 e 171). O códon que mais teve variações foi o códon 171, onde todos os alelos foram identificados. Um polimorfismo raro foi encontrado no códon 143, em 4 por cento das amostras analisadas, o qual tem sido descrito por aumentar a resistência a scrapie em animais suscetíveis. Nenhum outro polimorfismo foi detectado nos 12 códons restantes, todos então, correspondendo à proteína priônica selvagem. De acordo com a grau de risco a desenvolver scrapie, a maioria dos animais (96 por cento) tiveram genótipo correspondentes aos grupos de risco 1 a 3 (muito baixo a moderado), e somente 4 por cento no grupo de risco alto. Nossos dados discutem a relação das medidas de prevenção envolvendo a genotipagem e a seleção positiva para o controle da doença.