Prevalence and antimicrobial resistance of Salmonella spp isolated from free-ranging wild boars in the state of São Paulo, Brazil / Prevalência e resistência antimicrobiana de Salmonella spp isoladas em javalis de vida livre no estado de São Paulo

European wild boars (Sus scrofa) are considered exotic invasive species worldwide. Invasions of wild boars are a growing public health concern, as wild boars may represent an important reservoir of zoonotic pathogens, including bacteria of the genus Salmonella. The aim of this study was to determine the prevalence and serovars of Salmonella spp. in free-ranging wild boars legally hunted in the state of São Paulo, Brazil, and the susceptibility of those Salmonella spp. to antimicrobials. Fecal samples and mesenteric lymph nodes were acquired from 63 wild boars. The prevalence of Salmonella spp. in free-ranging wild boars was 9.5 % (6/63; confidence interval: 4.4 % - 19.2 %). Six serovars were isolated: S. enterica subsp. enterica ser. 4,5,12:-:1,2, S. enterica ser. Cerro, S. enterica ser. Madelia, S. enterica ser. Typhimurium, S. enterica ser. I (4,5,12:i:-) and S. enterica ser. Muenster. Analysis of antimicrobial resistance of Salmonella spp. showed that the majority of serovars were fully susceptible to the tested antimicrobials. Only S. enterica ser. Typhimurium and S. enterica ser. Muenster showed a resistance pattern to at least one antimicrobial analyzed. To our knowledge, this study is the first report the prevalence and serovars of Salmonella spp. in free-ranging wild boars in the State of São Paulo, Brazil. Results indicate a low prevalence with variability of Salmonella serovars, with some pattern of antimicrobial resistance. This study highlights the potential role of wild boars as carriers of Salmonella and could pose a risk to wild and domestic animals as well as humans.

Os javalis europeus (Sus scrofa) são considerados uma espécie exótica invasora em todo o mundo. As invasões de javalis são uma preocupação crescente de saúde pública, pois os javalis podem representar um importante reservatório de patógenos zoonóticos, incluindo bactérias do gênero Salmonella. O objetivo deste estudo foi determinar a prevalência e os sorovares de Salmonella spp. em javalis de vida livre caçados legalmente no Estado de São Paulo, Brasil, e a suscetibilidade dessa Salmonella spp. aos antimicrobianos. Amostras fecais e linfonodos mesentéricos foram adquiridos de 63 javalis. A prevalência de Salmonella spp. em javalis selvagens foi de 9,5% (6/63; intervalo de confiança: 4,4% - 19,2%). Seis sorovares foram isolados: S. enterica subsp. enterica ser. 4,5,12:-:1,2, S. enterica ser. Cerro, S. enterica ser. Madelia, S. enterica ser. Typhimurium, S. enterica ser. I (4,5,12:i:-) e S. enterica ser. Muenster. As análises de resistência antimicrobiana de Salmonella spp. evidenciaram que a maioria dos sorovares era pansensível aos antimicrobianos testados. Apenas S. enterica ser. Typhimurium e S. enterica ser. Muenster mostraram um padrão de resistência a pelo menos um antimicrobiano analisado. A saber, este estudo é o primeiro relato da prevalência e de sorovares de Salmonella spp. em javalis de vida livre no Estado de São Paulo, Brasil. Os resultados indicaram baixa prevalência com variabilidade de sorovares de Salmonella, com algum padrão de resistência antimicrobiana. Este estudo destaca o papel potencial dos javalis como portadores de Salmonella spp. e pode representar um risco para os animais domésticos e selvagens, bem como para os humanos.

A comparative evaluation of methods for estimating the colostrum quality in sows / Avaliação comparativa de métodos para estimar a qualidade do colostro em porcas

Colostrum is the main source of immunoglobulins (Ig) for neonate piglets and plays a crucial role within the health and growth of the piglet. Currently in pig farming, there are still no widespread practical methods for measuring the Ig concentration in colostrum at herd level. We evaluated sows' colostrum IgG concentration using an optical and a digital Brix refractometer and their performance was correlated to an IgG ELISA test, and flow cytometry. Colostrum concentrations of IgG and IgA averaged 74.05 ± 21.37mg/mL and 20.2 ± 5.32mg/mL respectively. The mean value of the Brix percentages for optical refractometer was 26.32%, and for digital was 28.32%. The Brix refractometer measurements of colostrum samples presented high correlation for IgG content analyzed by ELISA (Optical = 0.74, Digital = 0.87; P <0.001). Considering the immunophenotyping, the values for IgG and IgA lymphoblasts indicated a highly significant relationship to ELISA (IgG=0.77, IgA=0.84; P<0.001). The Brix refractometer can be considered a useful tool to be included in a colostrum monitoring program to improve potentially neonatal health. In addition, we demonstrated that flow cytometry can be an important tool to analyze and characterize the immunological potential of sow colostrum.(AU)

O colostro é a principal fonte de imunoglobulinas (Ig) para leitões recém-nascidos e desempenha um papel crucial na saúde e no crescimento dos leitões. Atualmente, na suinocultura, ainda não existem métodos amplamente utilizados na prática de produção para medir a concentração de imunoglobulinas no colostro suíno. Avaliou-se a concentração de IgG no colostro de porcas usando refratômetros Brix óptico e digital, e o desempenho foi comparado com ELISA e citometria de fluxo. As concentrações de IgG e IgA no colostro foram 74,05 ± 21,37mg/mL e 20,2 ± 5,32mg/mL, respectivamente. A percentagem de Brix média das amostras de colostro para o refratômetro óptico foi 26,32%, e para o digital foi 28,32%. As medições dos refratômetros de Brix apresentaram elevada correlação com a concentrações de IgG medidas por ELISA (óptico=0,74, digital=0,87; P<0,001). Considerando a imunofenotipagem, os valores dos linfoblastos IgG e IgA apresentaram alta correlação com o ELISA (IgG=0,77, IgA=0,84; P<0,001). O refratômetro Brix pode ser considerado uma ferramenta útil para ser incluída em um programa de monitoramento de colostro para melhorar a saúde neonatal. Além disso, foi demonstrado que a citometria de fluxo pode ser uma ferramenta importante para analisar e caracterizar o potencial imunológico do colostro de porcas.(AU)

Assessing the implications of mycotoxins on productive efficiency of broilers and growing pigs

The effects of mycotoxins on the productive performance of growing pigs and broilers were evaluated using meta-analytical approach. Two databases were constructed: (1) Broilers, with information collected from 51,497 birds and published in 158 scientific papers from 1980 to 2016; and (2) Pigs, with information collected from 7,743 animals and published in 72 scientific papers from 1980 to 2015. The meta-analyses were performed independently for each specie, following three sequential analyses: graphical, correlation, and variance-covariance. Broilers and pigs challenged by mycotoxins reduced (p < 0.05) feed intake by 9 and 6 %, weight gain by 15 and 11 %, and feed efficiency by 6 and 4 % compared with non-challenged animals, respectively. Aflatoxins were the most studied mycotoxins in both databases. Birds and pigs challenged by aflatoxins reduced (p < 0.05) feed intake by 10 and 8 %, growth by 15 and 11 %, and feed efficiency by 6 and 7 % compared to non-challenged animals, respectively. In both databases, variation on growth performance due to mycotoxins showed a linear relationship (p < 0.05) with the feed intake variation caused by the challenge. The intercepts of the regression-based equations were different from zero and negative, which may indicate that mycotoxins altered the maintenance requirements in challenged animals. In conclusion, both broilers and growing pigs show losses in performance responses and worse nutritional efficiency when challenged by mycotoxins.

Assessing the implications of mycotoxins on productive efficiency of broilers and growing pigs

The effects of mycotoxins on the productive performance of growing pigs and broilers were evaluated using meta-analytical approach. Two databases were constructed: (1) Broilers, with information collected from 51,497 birds and published in 158 scientific papers from 1980 to 2016; and (2) Pigs, with information collected from 7,743 animals and published in 72 scientific papers from 1980 to 2015. The meta-analyses were performed independently for each specie, following three sequential analyses: graphical, correlation, and variance-covariance. Broilers and pigs challenged by mycotoxins reduced (p < 0.05) feed intake by 9 and 6 %, weight gain by 15 and 11 %, and feed efficiency by 6 and 4 % compared with non-challenged animals, respectively. Aflatoxins were the most studied mycotoxins in both databases. Birds and pigs challenged by aflatoxins reduced (p < 0.05) feed intake by 10 and 8 %, growth by 15 and 11 %, and feed efficiency by 6 and 7 % compared to non-challenged animals, respectively. In both databases, variation on growth performance due to mycotoxins showed a linear relationship (p < 0.05) with the feed intake variation caused by the challenge. The intercepts of the regression-based equations were different from zero and negative, which may indicate that mycotoxins altered the maintenance requirements in challenged animals. In conclusion, both broilers and growing pigs show losses in performance responses and worse nutritional efficiency when challenged by mycotoxins.(AU)

Occurrence of antibodies against Neospora caninum in wild pigs (Sus scrofa) in the Pantanal, Mato Grosso do Sul, Brazil / Ocorrência de anticorpos contra Neospora caninum em porcos-monteiro (Sus scrofa) do Pantanal, Mato Grosso do Sul, Brasil

Serum samples from 83 free living wild pigs (Sus scrofa) from the Nhecolândia region, Pantanal do Mato Grosso, Brazil, were examined for the presence of antibodies against Neospora caninum by means of the indirect fluorescence antibody test (IFAT) with a cut off of 50. Antibodies were present in 10.8%, with titers of: 1:200 in one animal, 1:400 in four and 1:800 in four. Analysis using the χ2 test showed an association between sex and presence of antibodies, with females showing occurrence of 20.5% and males 2.3% (p = 0.017). No association was found between age and occurrences of antibodies against this parasite. This was the first observation of N. caninum antibodies in Brazilian wild pigs from Pantanal(AU)

Amostras de soro de 83 porcos-monteiro (Sus scrofa) selvagens, oriundos da região de Nhecolândia, Pantanal do Mato Grosso, Brasil, foram examinadas para a presença de anticorpos contra Neospora caninum pela reação de imunofluorescência indireta (RIFI) com ponto de corte de 50. A ocorrência de anticorpos foi de 10,8%, com um animal apresentando título de 1:200, quatro com 1:400 e quatro com 1:800. Quando analisados pelo teste do X2, foi observada a existência de associação entre sexo e presença de anticorpos, com as fêmeas apresentando ocorrência de 20,5% e os machos 2,3% (p = 0,017). Não houve associação entre idade e ocorrência de anticorpos contra este parasito. Esta é a primeira observação de porcos-monteiro da região do Pantanal, apresentando anticorpos contra N. caninum(AU)

Mixed mycotic rhinitis and pneumonia in wild boars

Background: Wild boar population is present worldwide. Contact between wild boars and domestic pigs may occur occasionally, and several diseases, as well as the occurrence of opportunistic infections are observed in both species. Mycotic rhinitis and pneumonia were reported before in pig herds, mainly associated with immunosuppression caused by viral infection. This study reports the occurrence of mycotic rhinitis in two wild boars due to Aspergillus fumigatus, A. fl avus and Candida albicans, together with Pneumocystis sp. in the lungs, originating from a herd infected with PCV2. Cases: In a commercial wild boar herd, poor body condition, sneezing and diarrhea were observed. Three animals were euthanized and, in two of them, yellow and green plaque-like masses of fungal growth in the mucosal and in cartilage surface and accentuated atrophy of nasal turbinates were observed. Additionally, multifocal subcutaneous abscesses in the maxillary area and bilateral reddening of the ocular mucosa with muco-purulent discharge were noted. Microscopically, in fragments from the nasal cavity of the two affected wild pigs, massive ulceration of the mucosal surface and presence of hyphae with septations and dichotomous branching and pseudohyphae were observed. Multifocal moderated interstitial pneumonia and alveolar edema were the main histological lesions founded in the lungs of 3 animals. In the lymph nodes multifocal moderated lymphoid depletion and lymphohistiocytic infi ltrated was the main microscopical lesion. Aspergillus fumigatus, A. fl avus and Candida albicans were isolated in nasal cavity. Pseudomonas aeruginosa was isolated from the subcutaneous abscesses and Staphylococcus hyicus and Streptococcus equisimilis from ocular swab. Pneumocystis was detected in lungs from the three wild boars by nested PCR, Grocott´s staining and immunohistochemistry (IHC). Porcine circovirus 2 (PCV2) was detected in lungs by PCR. Virus detection by IHC was only confi rmed in one wild boar. Discussion: Diagnostic of mycotic rhinitis and pneumonia was based on macroscopical and microscopical fi ndings, as well as mycological analysis, IHC and Groccott ´s methenamine staining. Pneumocystis carinii, Aspergillus spp. and Candida spp. are considered as opportunistic fungal pathogens commonly associated with immunosuppression in animals and humans and have been found in lungs and in muco-cutaneous tissue of PMWS affected pigs. Clinically, immunodeficiency is usually associated with illness caused by organisms of low pathogenicity or well-know secondary pathogens, among other factors. Besides immunodefi ciency, prolonged antimicrobial therapy is another predisposing factor to the development of mycotic infections, well described in animals. In the present report, antimicrobial therapy was performed when respiratory signs were noted in therapeutic doses, suggesting that massive antibiotic use was not the trigger of mycotic rhinitis. PCV2 IHC result positive only in one wild pig, although all the samples were positive by PCR. This fi nding could indicate a subclinical infection or a recovery phase of the disease in the IHC negative cases, as previously suggested for domestic and wild pigs using in situ hybridization. PCV2 load in wild boar was lower when compared with domestic pigs. A viral load higher than 108 PCV2 genomes per 500 ng DNA was required to give a visible IHC staining in swine. Although quantitative PCR it was not used in order to detect PCV2 in the present report, the viral load could be another possible explanation for the IHC negative cases observed. The role of PCV2 as a cause of immunosupression, facilitating the infection with secondary agents as Aspergillus, Candida and Pneumocystis cannot be ruled out.(AU)

Mixed mycotic rhinitis and pneumonia in wild boars

Background: Wild boar population is present worldwide. Contact between wild boars and domestic pigs may occur occasionally, and several diseases, as well as the occurrence of opportunistic infections are observed in both species. Mycotic rhinitis and pneumonia were reported before in pig herds, mainly associated with immunosuppression caused by viral infection. This study reports the occurrence of mycotic rhinitis in two wild boars due to Aspergillus fumigatus, A. fl avus and Candida albicans, together with Pneumocystis sp. in the lungs, originating from a herd infected with PCV2. Cases: In a commercial wild boar herd, poor body condition, sneezing and diarrhea were observed. Three animals were euthanized and, in two of them, yellow and green plaque-like masses of fungal growth in the mucosal and in cartilage surface and accentuated atrophy of nasal turbinates were observed. Additionally, multifocal subcutaneous abscesses in the maxillary area and bilateral reddening of the ocular mucosa with muco-purulent discharge were noted. Microscopically, in fragments from the nasal cavity of the two affected wild pigs, massive ulceration of the mucosal surface and presence of hyphae with septations and dichotomous branching and pseudohyphae were observed. Multifocal moderated interstitial pneumonia and alveolar edema were the main histological lesions founded in the lungs of 3 animals. In the lymph nodes multifocal moderated lymphoid depletion and lymphohistiocytic infi ltrated was the main microscopical lesion. Aspergillus fumigatus, A. fl avus and Candida albicans were isolated in nasal cavity. Pseudomonas aeruginosa was isolated from the subcutaneous abscesses and Staphylococcus hyicus and Streptococcus equisimilis from ocular swab. Pneumocystis was detected in lungs from the three wild boars by nested PCR, Grocott´s staining and immunohistochemistry (IHC). Porcine circovirus 2 (PCV2) was detected in lungs by PCR. Virus detection by IHC was only confi rmed in one wild boar. Discussion: Diagnostic of mycotic rhinitis and pneumonia was based on macroscopical and microscopical fi ndings, as well as mycological analysis, IHC and Groccott ´s methenamine staining. Pneumocystis carinii, Aspergillus spp. and Candida spp. are considered as opportunistic fungal pathogens commonly associated with immunosuppression in animals and humans and have been found in lungs and in muco-cutaneous tissue of PMWS affected pigs. Clinically, immunodeficiency is usually associated with illness caused by organisms of low pathogenicity or well-know secondary pathogens, among other factors. Besides immunodefi ciency, prolonged antimicrobial therapy is another predisposing factor to the development of mycotic infections, well described in animals. In the present report, antimicrobial therapy was performed when respiratory signs were noted in therapeutic doses, suggesting that massive antibiotic use was not the trigger of mycotic rhinitis. PCV2 IHC result positive only in one wild pig, although all the samples were positive by PCR. This fi nding could indicate a subclinical infection or a recovery phase of the disease in the IHC negative cases, as previously suggested for domestic and wild pigs using in situ hybridization. PCV2 load in wild boar was lower when compared with domestic pigs. A viral load higher than 108 PCV2 genomes per 500 ng DNA was required to give a visible IHC staining in swine. Although quantitative PCR it was not used in order to detect PCV2 in the present report, the viral load could be another possible explanation for the IHC negative cases observed. The role of PCV2 as a cause of immunosupression, facilitating the infection with secondary agents as Aspergillus, Candida and Pneumocystis cannot be ruled out.