Effect of parity segregation on Mycoplasma hyopneumoniae infection dynamics and pneumonic lesions in pigs / Efeito da ordem de parto segregada sobre a dinâmica de infecção de Mycoplasma hyopneumoniae e lesões pulmonares ao abate

Gilts represent a group risk for Mycoplasma hyopneumoniae vertical transmission in swine herds. Therefore, parity segregation can be an alternative to control M. hyopneumoniae infections. The study evaluated the effect of parity segregation on M. hyopneumoniae infection dynamics and occurrence and severity of lung lesions at slaughter. For that, three multiple site herds were included in the study. Herd A consisted of the farm where gilts would have their first farrowing (parity order (PO) 1). After the first farrowing PO 1 sows were transferred to herd B (PO2-6). Herd C was a conventional herd with gilt replacement (PO1-6). Piglets born in each herd were raised in separated nursery and finishing units. Sows (n = 33 (A), 37 (B), 34 (C)) in all herds were sampled prior to farrowing and piglets (n = 54 (A), 71 (B), 66 (C)) were sampled longitudinally at 21, 63, 100, 140 days of age and at slaughter for M. hyopneumoniae detection by PCR and lung lesions scoring. M. hyopneumoniae prevalence in sows did not differ among herds. Prevalence of positive piglets was higher at weaning in the PO1 herd (A) (P < 0.05). However, prevalence of positive pigs from 100 days of age to slaughter age was higher in the PO2-6 herd (B) (P < 0.05). Lung lesion occurrence and severity were higher in herd B. The authors suggested that the lack of a proper gilt acclimation might have influenced the results, leading to sows being detected positive at farrowing, regardless of the parity.

As leitoas consistem em um grupo de risco na transmissão vertical de Mycoplasma hyopneumoniae dentro do sistema de produção de suínos. Dessa forma, a segregação de partos poderia ser utilizada como alternativa para controlar as infecções por M. hyopneumoniae. O objetivo deste estudo foi avaliar o efeito da segregação de partos sobre a dinâmica de infecção de M. hyopneumoniae e a ocorrência e severidade das lesões pulmonares ao abate. Para isso três sistemas de produção de suínos com três sítios cada foram incluídos no estudo. A granja A consistia da unidade onde as leitoas tem o primeiro parto, ou seja, alojava somente de fêmeas de ordem de parto 1 (Granja OP1). Após o primeiro parto as fêmeas OP1 foram transferidas para a granja B (Granja OP2-6), ou seja, consistia de fêmeas de ordem de parto 2 a 6, e a granja C consistiu em uma granja convencional com reposição de leitoas (Granja OP1-6), com fêmeas de ordem de parto 1 a 6. Os leitões nascidos de cada granja foram transferidos e criados em creches e terminações segregadas. As matrizes (n = 33 (A), 37 (B), 34 (C)) de todas as granjas do estudo foram amostradas previamente ao parto e os leitões (n = 54 (A), 71 (B), 66 (C)) foram amostrados longitudinalmente aos 21, 63, 100 e 140 dias de idade e ao abate. Em todos os momentos de coleta, as amostras foram avaliadas por PCR para detecção de M. hyopneumoniae. As lesões pulmonares foram avaliadas e escores de lesão foram atribuídos ao abate. A prevalência de matrizes positivas para M. hyopneumoniae não diferiu entre as granjas (P > 0,05). A prevalência ao desmame foi maior na granja A (OP1) (P < 0,05). No entanto, dos 100 dias de idade até o abate a prevalência de leitões positivos para M. hyopneumoniae foi maior na granja B (OP2-6) (P < 0,05). A ocorrência e severidade de lesões pulmonares foram maiores na granja B. Os autores sugerem que a falta de uma aclimatação adequada das leitoas pode ter influenciado nos resultados, levando à detecção de matrizes positivas ao parto, independente da ordem de parto.

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)

Causes of death in growing-finishing pigs in two technified farms in southern Brazil / Causas de morte em suínos de crescimento e terminação em duas granjas tecnificadas no Sul do Brasil

The aim of this study was to investigate the main causes of death in growing-finishing pigs in southern Brazil. During a one-year period (from 2018 to 2019), two industrial pig herds (18 and 20 thousand pigs each farm) in southern Brazil were monitored along the four seasons of the year (12 days per season on each farm), in order to perform necropsies of all pigs that died in that period. The two farms had an average monthly mortality rate ranging from 0.94 to 3.93% in the evaluated months. At necropsy, tissues were collected, fixed in 10% formalin solution and processed routinely for histopathological examination. When necessary, samples were sent for bacterial culture and PCR to identify etiologic agents. A total of 601 necropsies were performed, with 94.9% of conclusive diagnoses. Infectious diseases corresponded to 64.4% of conclusive diagnosis and non-infectious diseases to 35.6%. The most prevalent causes of death were: pneumonia (33%), gastric ulcers (15.4%), circovirosis (9.9%), systemic bacterial embolism (5.4%), polyserositis (4.4%), dilated cardiomyopathy and torsion of abdominal organs (4.3% each), and bacterial pericarditis (3.4%). Regarding pneumonias (199/601), the main agents identified in these cases were Pasteurella multocida, Influenza A virus and Mycoplasma hyopneumoniae, mainly in associations.(AU)

O objetivo do presente trabalho foi investigar as principais causas de morte de suínos em fase de crescimento e terminação no Sul do Brasil. Durante o período de um ano (entre 2018 e 2019), duas granjas tecnificadas de suínos no Sul do Brasil foram acompanhadas nas quatro estações (12 dias por estação em cada granja), para realização de necropsias dos suínos que morreram nesse período. As duas propriedades apresentavam mortalidade mensal média entre 0,94 e 3,93% nos meses avaliados. Na necropsia, amostras de órgãos foram colhidas, fixadas em formol 10% e processadas rotineiramente para o exame histopatológico. Quando necessário, amostras foram enviadas para o cultivo bacteriano e PCR para identificação de agentes etiológicos. Foram realizadas um total de 601 necropsias, com 94,9% de diagnósticos conclusivos. As doenças infecciosas corresponderam a 64,4% dos diagnósticos conclusivos e as não infecciosas a 35,6%. As principais causas de morte foram: pneumonias (33%), úlcera gástrica (15,4%), circovirose (9,9%), embolia bacteriana sistêmica (5,4%), polisserosite (4,4%), cardiomiopatia dilatada e torção de órgãos abdominais (4,3% cada) e pericardite bacteriana (3,4%). Com relação às pneumonias (199/601), os principais agentes associadas as lesões foram Pasteurella multocida, vírus da Influenza A e Mycoplasma hyopneumoniae, principalmente associados entre si.(AU)

Causes of death in growing-finishing pigs in two technified farms in southern Brazil / Causas de morte em suínos de crescimento e terminação em duas granjas tecnificadas no Sul do Brasil

The aim of this study was to investigate the main causes of death in growing-finishing pigs in southern Brazil. During a one-year period (from 2018 to 2019), two industrial pig herds (18 and 20 thousand pigs each farm) in southern Brazil were monitored along the four seasons of the year (12 days per season on each farm), in order to perform necropsies of all pigs that died in that period. The two farms had an average monthly mortality rate ranging from 0.94 to 3.93% in the evaluated months. At necropsy, tissues were collected, fixed in 10% formalin solution and processed routinely for histopathological examination. When necessary, samples were sent for bacterial culture and PCR to identify etiologic agents. A total of 601 necropsies were performed, with 94.9% of conclusive diagnoses. Infectious diseases corresponded to 64.4% of conclusive diagnosis and non-infectious diseases to 35.6%. The most prevalent causes of death were: pneumonia (33%), gastric ulcers (15.4%), circovirosis (9.9%), systemic bacterial embolism (5.4%), polyserositis (4.4%), dilated cardiomyopathy and torsion of abdominal organs (4.3% each), and bacterial pericarditis (3.4%). Regarding pneumonias (199/601), the main agents identified in these cases were Pasteurella multocida, Influenza A virus and Mycoplasma hyopneumoniae, mainly in associations.(AU)

O objetivo do presente trabalho foi investigar as principais causas de morte de suínos em fase de crescimento e terminação no Sul do Brasil. Durante o período de um ano (entre 2018 e 2019), duas granjas tecnificadas de suínos no Sul do Brasil foram acompanhadas nas quatro estações (12 dias por estação em cada granja), para realização de necropsias dos suínos que morreram nesse período. As duas propriedades apresentavam mortalidade mensal média entre 0,94 e 3,93% nos meses avaliados. Na necropsia, amostras de órgãos foram colhidas, fixadas em formol 10% e processadas rotineiramente para o exame histopatológico. Quando necessário, amostras foram enviadas para o cultivo bacteriano e PCR para identificação de agentes etiológicos. Foram realizadas um total de 601 necropsias, com 94,9% de diagnósticos conclusivos. As doenças infecciosas corresponderam a 64,4% dos diagnósticos conclusivos e as não infecciosas a 35,6%. As principais causas de morte foram: pneumonias (33%), úlcera gástrica (15,4%), circovirose (9,9%), embolia bacteriana sistêmica (5,4%), polisserosite (4,4%), cardiomiopatia dilatada e torção de órgãos abdominais (4,3% cada) e pericardite bacteriana (3,4%). Com relação às pneumonias (199/601), os principais agentes associadas as lesões foram Pasteurella multocida, vírus da Influenza A e Mycoplasma hyopneumoniae, principalmente associados entre si.(AU)

Virulence factors and antimicrobial resistance profile of Escherichia coli isolated from nursery piglets and drinking water

Background: One of the most frequent health problems in the swine industry is the post-weaning diarrhea in nursery pigs, which leads to significant losses due to weight loss, dehydration, cost of medication and mortality. Escherichia coli (E. coli) is one of the main bacterial agents of the post-weaning diarrhea. To investigate the possibility of enterotoxigenic E. coli (ETEC) transmission through drinking water to nursery piglets, the objective of this study was to isolate, characterize by virulence factors, and compare the antimicrobial resistance profiles of E. coli from drinking water samples in nurseries and from rectal swabs of their piglets presenting post-weaning colibacillosis.Materials, Methods & Results: Fifteen rectal swabs from diarrheic piglets in their first three weeks after weaning and one water sample were collected from each of ten nurseries located in Rio Grande do Sul State, south of Brazil. After enrichment with a commercial broth medium, water samples were cultured in blood agar, as well as the rectal swab samples, and the characteristic colonies were identified by standard biochemical analysis. Following isolation and identification of E. coli, the colonies from water samples and their corresponding piglets’ samples were characterized by multiplex PCR in order to determine specific ETEC fimbria and toxin genes. Finally, all E. coli isolates were submitted to antimicrobial susceptibility testing. Virulence factors and antimicrobial sensitivity could then be compared between water and piglets’ samples. The difference in the antimicrobial resistance frequency for each of the sample groups were compared using the multi comparison test. E. coli was isolated in four out of the ten water samples, although none of the water samples presented ETEC virulence factors.[...]

Virulence factors and antimicrobial resistance profile of Escherichia coli isolated from nursery piglets and drinking water

Background: One of the most frequent health problems in the swine industry is the post-weaning diarrhea in nursery pigs, which leads to significant losses due to weight loss, dehydration, cost of medication and mortality. Escherichia coli (E. coli) is one of the main bacterial agents of the post-weaning diarrhea. To investigate the possibility of enterotoxigenic E. coli (ETEC) transmission through drinking water to nursery piglets, the objective of this study was to isolate, characterize by virulence factors, and compare the antimicrobial resistance profiles of E. coli from drinking water samples in nurseries and from rectal swabs of their piglets presenting post-weaning colibacillosis.Materials, Methods & Results: Fifteen rectal swabs from diarrheic piglets in their first three weeks after weaning and one water sample were collected from each of ten nurseries located in Rio Grande do Sul State, south of Brazil. After enrichment with a commercial broth medium, water samples were cultured in blood agar, as well as the rectal swab samples, and the characteristic colonies were identified by standard biochemical analysis. Following isolation and identification of E. coli, the colonies from water samples and their corresponding piglets samples were characterized by multiplex PCR in order to determine specific ETEC fimbria and toxin genes. Finally, all E. coli isolates were submitted to antimicrobial susceptibility testing. Virulence factors and antimicrobial sensitivity could then be compared between water and piglets samples. The difference in the antimicrobial resistance frequency for each of the sample groups were compared using the multi comparison test. E. coli was isolated in four out of the ten water samples, although none of the water samples presented ETEC virulence factors.[...](AU)

Cardiac rhabdomyoma in a slaughtered pig / Rabdomioma cardíaco em um suíno de abate

Rhabdomyoma is a rare neoplasm of striated muscle that occurs predominantly in the myocardium. In animals, cardiac rhabdomyoma are observed as incidental lesions in slaughter pigs and have been rarely described in other species, such as cattle, dogs, and deer. This report describes a case of cardiac rhabdomyoma in a male pig at slaughter age that died suddenly in the pre-slaughter period. At necropsy, multiple nodules were observed in the right and left ventricular walls and the interventricular septum. Histopathological examination showed neoplastic proliferation composed of polyhedral cells, with vacuolated cytoplasm that sometimes presented a spider cell appearance. Histochemical staining with Schiffs periodic acid revealed glycogen granules in the cytoplasm of neoplastic cells. The neoplastic cells were positive for desmin, neuron-specific enolase, atrial natriuretic peptide, and vimentin by immunohistochemistry, to varying degrees. The anatomopathological and immunohistochemical findings observed in this case confirmed the diagnosis of cardiac rhabdomyoma, possibly originating from the Purkinje fibers.(AU)

Rabdomioma é um neoplasma raro de músculo estriado que ocorre predominantemente no miocárdio. Em animais rabdomiomas cardíacos são observados como lesões incidentais em suínos de abate, raramente descrito em outras espécies como bovinos, cães e cervos. Neste relato descreve-se um caso de rabdomioma cardíaco em um suíno, macho, em idade de abate que morreu subitamente no período pré-abate. Na necropsia visualizou-se múltiplos nódulos nas paredes ventriculares direita e esquerda, e septo interventricular. O exame histopatológico mostrou proliferação neoplásica composta por células poliédricas, com citoplasma vacuolizado que por vezes apresentavam aspecto de célula de aranha. Na coloração histoquímica de ácido periódico de Schiff evidenciaram-se grânulos de glicogênio no citoplasma das células neoplásicas. As células neoplásicas foram imunorreativas na imuno-histoquímica para desmina, enolase neurônio específica, peptídeo natriurético atrial e vimentina em diferentes graus. Os achados anatomopatológicos e imuno-histoquímicos observados neste caso confirmam o diagnóstico de rabdomioma cardíaco, possivelmente com origem das fibras de Purkinje.(AU)

Coristoma ósseo mesentérico em uma porca / Mesenteric osseous choristoma in a sow

Background: Osseous choristomas represent the production of osseous tissue in abnormal regions, such as subcutaneous, fibrous or perivascular tissues, skeletal muscle and skin. These structures have been found in humans, dogs (lungs and dura mater), horses (large intestines) and cattle (lungs and mesenteric lymph nodes). They were also found in the mesenteric region and thoracic cavity of sows and piglets. The aim of this paper was to describe the macro and microscopic lesions found in a sow which died suddenly by a rare mesenteric osseous choristoma. Case: A lactating sow, parity four, from the Swine Department of the Federal University of Rio Grande do Sul (UFRGS), Brazil, showed appetite loss, hyperthermia (41.5ºC) and sudden death. The animal was submitted to necropsy at the Department of Veterinary Pathology, UFRGS. On external examination, the sow showed conjunctival and perioral cyanosis, proximal colon region with a firm structure with approximately 3.0 cm length in mesenteric area. Moreover, the colon was ruptured and fibrin deposition and intestinal content in abdominal cavity were observed. Fragments of organs were collected in 10% formalin, routinely processed for histology and colored with hematoxylin and eosin stain (H&E). Histologically, it was found bone trabeculae with osteoid, periosteum, spaces with osteocids and endochondral ossification with bone marrow composed by adipose tissue and intense proliferation of conjunctive stroma. The mesenteric lymph nodes showed intense lymphoid hyperplasia with multifocal centrilobular necrosis. There was fibrin in serosa of colon, acute peri-spleen and acute fibrinopurulent perihepatitis. Discussion: Macroscopic and microscopic findings were consistent with mesenteric osseous choristoma. This condition is unusual in domestic animals, however it has been already described in pigs...

Coristoma ósseo mesentérico em uma porca / Mesenteric osseous choristoma in a sow

Background: Osseous choristomas represent the production of osseous tissue in abnormal regions, such as subcutaneous, fibrous or perivascular tissues, skeletal muscle and skin. These structures have been found in humans, dogs (lungs and dura mater), horses (large intestines) and cattle (lungs and mesenteric lymph nodes). They were also found in the mesenteric region and thoracic cavity of sows and piglets. The aim of this paper was to describe the macro and microscopic lesions found in a sow which died suddenly by a rare mesenteric osseous choristoma. Case: A lactating sow, parity four, from the Swine Department of the Federal University of Rio Grande do Sul (UFRGS), Brazil, showed appetite loss, hyperthermia (41.5ºC) and sudden death. The animal was submitted to necropsy at the Department of Veterinary Pathology, UFRGS. On external examination, the sow showed conjunctival and perioral cyanosis, proximal colon region with a firm structure with approximately 3.0 cm length in mesenteric area. Moreover, the colon was ruptured and fibrin deposition and intestinal content in abdominal cavity were observed. Fragments of organs were collected in 10% formalin, routinely processed for histology and colored with hematoxylin and eosin stain (H&E). Histologically, it was found bone trabeculae with osteoid, periosteum, spaces with osteocids and endochondral ossification with bone marrow composed by adipose tissue and intense proliferation of conjunctive stroma. The mesenteric lymph nodes showed intense lymphoid hyperplasia with multifocal centrilobular necrosis. There was fibrin in serosa of colon, acute peri-spleen and acute fibrinopurulent perihepatitis. Discussion: Macroscopic and microscopic findings were consistent with mesenteric osseous choristoma. This condition is unusual in domestic animals, however it has been already described in pigs...(AU)

Comparison of phenotypic and genotypic identification methods of Pasteurella multocida serotypes isolated from pigs

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...](AU)

Frequency of Methicillin-resistant Staphylococcus aureus (MRSA) in fattening pigs in the state of Rio Grande do Sul, Brazil

Background: Staphylococcus (S.) aureus is an important nosocomial pathogen in humans and animals worldwide. The commonest class of antibiotics used to treat staphylococcal infections is the -lactams. Frequently, S. aureus strains show high resistance to methicillin and other -lactam antibiotics, called Methicillin-resistant Staphylococcus aureus (MRSA). Although MRSA has emerged at slower rate in domestic animals, it has frequently been found in the nasal cavity of healthy piglets and its transmission between pigs and swine handlers has already been studied. The aim of this work was to assess the presence of MRSA in finishing pigs in the state of Rio Grande do Sul, Brazil. Materials, Methods & Results: A total of 350 nasal swabs were collected from 10 to 20 week old finishing pigs. Sampling was performed in five pig farms in northeast Rio Grande do Sul State, Brazil. Swabs were stored in tubes without transport medium and carried to the laboratory under refrigeration. The specimens were cultured in selective and differential Agar (Baird Parker) and then were incubated at 37ºC for 48 h. After isolation of typical colonies of S. aureus, they were inoculated in BHI (Brain Heart Infusion) broth at 37ºC for 24 h and tested for tube coagulase activity. Coagulase positive samples were selected for growth in Oxacillin Resistant Screening Agar (ORSA) supplemented with 2 mg/L [...](AU)

Frequency of Methicillin-resistant Staphylococcus aureus (MRSA) in fattening pigs in the state of Rio Grande do Sul, Brazil

Background: Staphylococcus (S.) aureus is an important nosocomial pathogen in humans and animals worldwide. The commonest class of antibiotics used to treat staphylococcal infections is the -lactams. Frequently, S. aureus strains show high resistance to methicillin and other -lactam antibiotics, called Methicillin-resistant Staphylococcus aureus (MRSA). Although MRSA has emerged at slower rate in domestic animals, it has frequently been found in the nasal cavity of healthy piglets and its transmission between pigs and swine handlers has already been studied. The aim of this work was to assess the presence of MRSA in finishing pigs in the state of Rio Grande do Sul, Brazil. Materials, Methods & Results: A total of 350 nasal swabs were collected from 10 to 20 week old finishing pigs. Sampling was performed in five pig farms in northeast Rio Grande do Sul State, Brazil. Swabs were stored in tubes without transport medium and carried to the laboratory under refrigeration. The specimens were cultured in selective and differential Agar (Baird Parker) and then were incubated at 37ºC for 48 h. After isolation of typical colonies of S. aureus, they were inoculated in BHI (Brain Heart Infusion) broth at 37ºC for 24 h and tested for tube coagulase activity. Coagulase positive samples were selected for growth in Oxacillin Resistant Screening Agar (ORSA) supplemented with 2 mg/L [...]

Comparison of phenotypic and genotypic identification methods of Pasteurella multocida serotypes isolated from pigs

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...]

Phylogenetic characterization of the first Ungulate tetraparvovirus 2 detected in pigs in Brazil

Ungulate tetraparvovirus 2 (UTV2) , formerly known as porcine hokovirus due to its discovery in Hong Kong, is closely related to a Primate tetraparvovirus (human PARV-4) and Ungulate tetraparvovirus 1 (bovine hokovirus). Until now, UTV2 was detected in European, Asian and North American countries, but its occurrence in Latin America is still unknown. This study describes the first report of UTV2 in Brazil, as well as its phylogenetic characterization. Tissue samples (lymph node, lung, liver, spleen and kidney) of 240 piglets from eight different herds (30 animals each herd) were processed for DNA extraction. UTV2 DNA was detected by PCR and the entire VP1/VP2 gene was sequenced for phylogenetic analysis. All pigs from this study displayed postweaning multisystemic wasting syndrome (PMWS). UTV2 was detected in 55.3% of the samples distributed in the variety of porcine tissues investigated, as well as detected in almost all herds, with one exception. The phylogenetic analysis demonstrated that Brazilian UTV2 sequences were more closely related to sequences from Europe and United States.(AU)

First evidence of bovine viral diarrhea virus infection in wild boars / Primeira evidência da infecção pelo vírus da diarreia viral bovina em javalis

Background: The farming of wild boars has growing due to the interest of the human consumption of this exotic meat. Such a development may pose an increased risk of disease transmission between boars and domestic animals. The wild boar population has increased in South America in the last years due the absence of predator causing economic losses due to direct damage to crops and risk of disease transmission. The genus Pestivirus within the family Flaviviridae are composed by four recognized species by the International Committee on the Taxonomy of Viruses (ICTV): classical swine fever virus (CSFV), border disease virus (BDV), bovine viral diarrhea virus type 1 (BVDV-1) and 2 (BVDV-2). Other putative species denoted as atypical pesitiviruses have been reported as HoBi-like virus, giraffe pestivirus, Bungowannah pestivirus, Pronghorn antelope virus, atypical porcine pestivirus (APPV), Norwegian rat pestivirus (NrPV) and Rhinolophus affinis bat pestivirus (RaPestV-1). CSFV is commonly detected in wild boars, but despite positive serology, bovine viral diarrhea virus (BVDV) was never detected in this animal species. Thereby, the present communication describes the first detection of BVDV in the lungs of captive boars using RT-PCR and DNA sequencing.Materials, Methods & Results: Forty lung samples from farmed wild boars were collected after slaughter in a commercial abattoir. [...](AU)

Primeira evidência da infecção pelo vírus da diarreia viral bovina em javalis / First evidence of bovine viral diarrhea virus infection in wild boars

Background: The farming of wild boars has growing due to the interest of the human consumption of this exotic meat. Such a development may pose an increased risk of disease transmission between boars and domestic animals. The wild boar population has increased in South America in the last years due the absence of predator causing economic losses due to direct damage to crops and risk of disease transmission. The genus Pestivirus within the family Flaviviridae are composed by four recognized species by the International Committee on the Taxonomy of Viruses (ICTV): classical swine fever virus (CSFV), border disease virus (BDV), bovine viral diarrhea virus type 1 (BVDV-1) and 2 (BVDV-2). Other putative species denoted as atypical pesitiviruses have been reported as ‘HoBi-like virus, giraffe pestivirus, Bungowannah pestivirus, Pronghorn antelope virus, atypical porcine pestivirus (APPV), Norwegian rat pestivirus (NrPV) and Rhinolophus affinis bat pestivirus (RaPestV-1). CSFV is commonly detected in wild boars, but despite positive serology, bovine viral diarrhea virus (BVDV) was never detected in this animal species. Thereby, the present communication describes the first detection of BVDV in the lungs of captive boars using RT-PCR and DNA sequencing.Materials, Methods & Results: Forty lung samples from farmed wild boars were collected after slaughter in a commercial abattoir. The organs were crushed separately, centrifuged, and the supernatant was stored for further analysis. The total RNA was isolated using a phenol-based protocol and RT-PCR protocol that amplified 118 bp of 5 untranslated region (5UTR) was carried out. One out 40 samples resulted positive. The positive sample had partial fragments of 5UTR and N terminal autoprotease (Npro) sequenced and analyzed. The strain LV Java/2012 presented 99% of identity in 5UTR and 98% in Npro region with a BVDV-2 previously reported in bovines in Southern Brazil.[...](AU)

Primeira evidência da infecção pelo vírus da diarreia viral bovina em javalis / First evidence of bovine viral diarrhea virus infection in wild boars

Background: The farming of wild boars has growing due to the interest of the human consumption of this exotic meat. Such a development may pose an increased risk of disease transmission between boars and domestic animals. The wild boar population has increased in South America in the last years due the absence of predator causing economic losses due to direct damage to crops and risk of disease transmission. The genus Pestivirus within the family Flaviviridae are composed by four recognized species by the International Committee on the Taxonomy of Viruses (ICTV): classical swine fever virus (CSFV), border disease virus (BDV), bovine viral diarrhea virus type 1 (BVDV-1) and 2 (BVDV-2). Other putative species denoted as atypical pesitiviruses have been reported as ‘HoBi’-like virus, giraffe pestivirus, Bungowannah pestivirus, Pronghorn antelope virus, atypical porcine pestivirus (APPV), Norwegian rat pestivirus (NrPV) and Rhinolophus affinis bat pestivirus (RaPestV-1). CSFV is commonly detected in wild boars, but despite positive serology, bovine viral diarrhea virus (BVDV) was never detected in this animal species. Thereby, the present communication describes the first detection of BVDV in the lungs of captive boars using RT-PCR and DNA sequencing.Materials, Methods & Results: Forty lung samples from farmed wild boars were collected after slaughter in a commercial abattoir. The organs were crushed separately, centrifuged, and the supernatant was stored for further analysis. The total RNA was isolated using a phenol-based protocol and RT-PCR protocol that amplified 118 bp of 5’ untranslated region (5’UTR) was carried out. One out 40 samples resulted positive. The positive sample had partial fragments of 5’UTR and N terminal autoprotease (Npro) sequenced and analyzed. The strain LV Java/2012 presented 99% of identity in 5’UTR and 98% in Npro region with a BVDV-2 previously reported in bovines in Southern Brazil.[...]

Associação entre fatores de virulência e resistência antimicrobiana de Escherichia coli enterotoxigênicas isoladas de leitões com diarreia no Brasil / Association between virulence factors and antimicrobial resistance from enterotoxigenic Escherichia coli isolated from pigs with diarrhea in Brazil

Background: Enterotoxigenic Escherichia coli (ETEC) is the etiologic agent of post weaning colibacillosis, one of the most important diseases in pig farming. The pathogenesis of the disease is associated with two virulence factors (VF), fimbriae and enterotoxins. In veterinary medicine, the use of antibiotics can lead to the selection of resistant bacteria. The association of VF and antibiotic resistance is an important mechanism for bacterial survival under adverse conditions. This study aimed to determine the VF and antimicrobial susceptibility of ETEC isolates from piglets with diarrhea and analyze the association between these factors.Materials, Methods & Results: A total of 185 rectal swabs were collected from weaned piglets in Brazilian farms of the states of Rio Grande do Sul, Santa Catarina, Paraná, Minas Gerais and Goiás. The isolation of ETEC was carried out on blood and MacConkey Agar and characterization by biochemical tests and detection by PCR of fimbrial genes F4, F45, F6, F18 and F41, and toxins genes LT, STa, STb and STx2e. Antimicrobial susceptibility profiles were determined by Agar diffusion test for amoxicillin, ampicillin, ceftiofur, ciprofloxacin, colistin, doxycycline, enrofloxacin, florfenicol, gentamicin, neomycin, norfloxacin, oxytetracycline, streptomycin, tetracycline, lincomycin + spectinomycin and sulfamethoxazole + trimethoprim. The association between VF and antimicrobials resistance results was determined by Chi-square and Fisher test (P ≤ 0.05). A total of 376 isolates were analyzed. The frequencies of fimbriae and toxins amplified were: F4 (31.6%), F18 (18.9%), F5 (4.2%) and toxins STa (43.1%), STb (24.7%), LT (21.8%) and STx2e (5.3%). Antibiotic resistance was higher to tetracycline (96.3%), florfenicol (95.2%), oxytetracycline (93.62%) and doxycycline (90.7%). Lowest levels of resistance were to ceftiofur (2.1%), colistin (9.8%), lincomycin + spectinomicin (15.4%) and neomycin (23.1%).[...](AU)

Associação entre fatores de virulência e resistência antimicrobiana de Escherichia coli enterotoxigênicas isoladas de leitões com diarreia no Brasil / Association between virulence factors and antimicrobial resistance from enterotoxigenic Escherichia coli isolated from pigs with diarrhea in Brazil

Background: Enterotoxigenic Escherichia coli (ETEC) is the etiologic agent of post weaning colibacillosis, one of the most important diseases in pig farming. The pathogenesis of the disease is associated with two virulence factors (VF), fimbriae and enterotoxins. In veterinary medicine, the use of antibiotics can lead to the selection of resistant bacteria. The association of VF and antibiotic resistance is an important mechanism for bacterial survival under adverse conditions. This study aimed to determine the VF and antimicrobial susceptibility of ETEC isolates from piglets with diarrhea and analyze the association between these factors.Materials, Methods & Results: A total of 185 rectal swabs were collected from weaned piglets in Brazilian farms of the states of Rio Grande do Sul, Santa Catarina, Paraná, Minas Gerais and Goiás. The isolation of ETEC was carried out on blood and MacConkey Agar and characterization by biochemical tests and detection by PCR of fimbrial genes F4, F45, F6, F18 and F41, and toxins genes LT, STa, STb and STx2e. Antimicrobial susceptibility profiles were determined by Agar diffusion test for amoxicillin, ampicillin, ceftiofur, ciprofloxacin, colistin, doxycycline, enrofloxacin, florfenicol, gentamicin, neomycin, norfloxacin, oxytetracycline, streptomycin, tetracycline, lincomycin + spectinomycin and sulfamethoxazole + trimethoprim. The association between VF and antimicrobials resistance results was determined by Chi-square and Fisher test (P ≤ 0.05). A total of 376 isolates were analyzed. The frequencies of fimbriae and toxins amplified were: F4 (31.6%), F18 (18.9%), F5 (4.2%) and toxins STa (43.1%), STb (24.7%), LT (21.8%) and STx2e (5.3%). Antibiotic resistance was higher to tetracycline (96.3%), florfenicol (95.2%), oxytetracycline (93.62%) and doxycycline (90.7%). Lowest levels of resistance were to ceftiofur (2.1%), colistin (9.8%), lincomycin + spectinomicin (15.4%) and neomycin (23.1%).[...]

Outbreak of cumarin poisoning in suckling piglets / Surto de intoxicação por cumarínico em leitões de maternidade

Background: Cumarin, also called warfarin, is used as an anticoagulant rodenticide. Pigs can be accidentally poisoned by ingestion of baits and/or dead rodents contaminated with cumarin and/or its criminal use. The clinical signs typically begin one to three days after ingestion of the rodenticide, when subcutaneous hematomas, epistaxis, among others symptoms, can be observed. The macroscopic and microscopic changes consist mainly of widespread hemorrhages in several organs. The objective of the present study is to report a rare case of cumarin poisoning in suckling piglets.Case: Four male piglets 18 days old were examined in the Department of Veterinary Pathology, Federal University of Rio Grande do Sul. The animals came from a farrowing unit located in the state of Rio Grande do Sul, Brazil, with a history of sudden death in piglets from different litters. The animals were submitted to necropsy. On external examination, the piglets had marked pallor of the oral and conjunctival mucosa and multiple petechiae and bruises on the skin of the ventral abdomen and bleeding on the white line of the hoof. During the internal examination, it was identified that there were multiple areas of hemorrhage in the subcutaneous tissue and skeletal muscles besides the thymus, liver, stomach, pancreas, bladder, kidney, heart and cerebellum. The mesenteric and inguinal lymph nodes, testicles and...(AU)

Derivados cumarínicos, também chamados varfarínicos, são compostos da cumarina utilizados como rodenticidas anticoagulantes em granjas de suínos como forma de controle de roedores [7]. Suínos podem se intoxicar acidentalmente através da ingestão de iscas e/ou roedores mortos por estas substâncias, ou pelo uso criminoso das mesmas [6]. Esses compostos inibem de forma competitiva a vitamina K epóxi redutase, enzima necessária para converter a vitamina K epóxi à sua forma reduzida, que é necessária para ativação dos fatores de coagulação II, VII, IX e X, consequentemente, a coagulação é comprometida [7]. A ingestão de 3 mg/kg em dose única pode ser suficiente para levar à intoxicação de suínos [2]. Já as doses de 0,05 mg/kg, se ingeridas por sete dias, também podem intoxicar os animais [5]. Os sinais clínicos normalmente surgem um a três dias após ingestão do raticida, sendo observados principalmente hematomas subcutâneos e epistaxe. As alterações macroscópicas e microscópicas consistem de hemorragias disseminadas em diversos órgãos [6]. O diagnóstico diferencial deve incluir carência de vitamina K; tratamento com quimioterápicos por períodos prolongados; intoxicação por chumbo, fosfato de zinco, ricina (da mamona), aflatoxinas e venenos ofídicos [6] e, principalmente, trombocitopenia púrpura dos leitões [9]. Dessa forma, a descrição de um surto de intoxicação por cumarínico pode...(AU)