Salinomycin intoxication in pigs associated with the use of tiamulin in the State of Santa Catarina, Brazil / Intoxicação por salinomicina em suínos associado ao uso de tiamulina no Estado de Santa Catarina

This paper describes a spontaneous outbreak of toxic myopathy in finishing pigs due to the ingestion of feed with salinomycin associated with tiamulin and addresses the control methods performed during the outbreak to minimize economic losses resulting from the intoxication. A lot of 940 pigs fed feed containing 30 ppm salinomycin received 100 ppm tiamulin (via water) to control recurrent respiratory diseases on the farm. After ingesting tiamulin, some animals manifested clinical signs of motor incoordination, stiff gait, reluctance to move, muscle weakness and tremors, dyspnea, depression, and decubitus, remaining in "sitting-dog position" or with the abduction of the pelvic limbs, and rested on tip-toes when in a standing position. Two animals were euthanized for macro-and microscopic evaluation. The other sick animals received supportive anti-inflammatory treatment. The most relevant macroscopic finding observed during necropsy was the slight pallor of the pelvic limb muscles. The main histopathological findings consisted of multifocal areas of hyaline degeneration and marked necrosis of skeletal myofibers, with macrophage infiltrate associated with cell regeneration and skeletal fiber phagocytosis. These lesions were more intense in the longissimus dorsi, diaphragm, and masseter muscles. The definitive diagnosis was based on epidemiological aspects and clinical lesional conditions compatible with toxic myopathy secondary to ionophore intoxication.(AU)

Este trabalho descreve um surto espontâneo de miopatia tóxica em suínos na fase de terminação, decorrente da ingestão de ração contendo salinomicina associada a tiamulina e aborda os métodos de controle realizados durante o surto, para minimizar os prejuízos econômicos decorrentes da intoxicação. Um lote de 940 suínos alimentados com ração contendo 30 ppm de salinomicina recebeu tiamulina na dose de 100 ppm (via água) para controle de doenças respiratórias recorrentes na granja. Após a ingestão da tiamulina, alguns animais manifestaram sinais clínicos de incoordenação motora, andar rígido, relutância ao movimento, fraqueza e tremores musculares, dispneia, depressão e decúbito, permanecendo em "posição de cão sentado" ou com abdução dos membros pélvicos, e quando em estação, apoiavam-se nas pinças dos cascos. Dois animais foram eutanasiados para avaliação macro e microscópica. Os demais animais doentes receberam tratamento suporte com anti-inflamatório. O achado macroscópico mais relevante observado durante a necropsia foi palidez leve dos músculos dos membros pélvicos. Os principais achados histopatológicos foram áreas multifocais de degeneração hialina e necrose acentuada de miofibras esqueléticas, com infiltrado de macrófagos associado às figuras de regeneração celular e à fagocitose de fibras esqueléticas. Essas lesões foram mais intensas nos músculos longissimus dorsi, diafragma e masseter. O diagnóstico definitivo baseou-se nos aspectos epidemiológicos e no quadro clínico-lesional compatíveis com miopatia tóxica secundária a intoxicação por ionóforo.(AU)

Estimation of productive losses caused by withdrawal of antibiotic growth promoter from pig diets Meta-analysis

ABSTRACT: This study was designed to simulate productive and economic losses due to the withdrawal of antibiotic growth promoters (AGP) from pig diets. Articles that compared diets with AGP (AGP+) or without AGP (AGP) for pigs were collected from electronic databases and the performance results were entered in a database. A meta-analysis was performed following the sequence: graphical analysis, correlation, and variance-covariance. The performance results observed in the meta-analysis, feed cost, and AGP costs were used to build equations to estimate the economic effect of withdrawing AGP. The database comprised 81 scientific articles containing 103 experiments totalizing 42,923 pigs. Avilamycin (24.7 %) was the most frequent AGP in the database, followed by Colistin (15.4 %), Tiamulin (11.7 %), Tylosin (8.0 %), Lincomycin (9.4 %), and Bacitracin (5.4 %). Weight gain (p 0.05) increased in AGP+ diets during post-weaning (6.5 %). However, there was no effect of AGP on weight gain of growing-finishing pigs. There was better (p 0.05) feed conversion in pigs fed AGP+ diets in all rearing phases. Weight gain and feed conversion improved (p 0.05) with the addition of Avilamycin, Bacitracin, and Tylosin. AGP withdrawal in the post-weaning phase increased feed costs by US$ 0.86 per animal and in growing-finishing phase the increase was US$ 3.11. Thus, pigs fed AGP+ diets have a better performance than pigs fed AGP- diets and the withdrawal of AGP increases feed costs.

Estimation of productive losses caused by withdrawal of antibiotic growth promoter from pig diets – Meta-analysis

This study was designed to simulate productive and economic losses due to the withdrawal of antibiotic growth promoters (AGP) from pig diets. Articles that compared diets with AGP (AGP+) or without AGP (AGP–) for pigs were collected from electronic databases and the performance results were entered in a database. A meta-analysis was performed following the sequence: graphical analysis, correlation, and variance-covariance. The performance results observed in the meta-analysis, feed cost, and AGP costs were used to build equations to estimate the economic effect of withdrawing AGP. The database comprised 81 scientific articles containing 103 experiments totalizing 42,923 pigs. Avilamycin (24.7 %) was the most frequent AGP in the database, followed by Colistin (15.4 %), Tiamulin (11.7 %), Tylosin (8.0 %), Lincomycin (9.4 %), and Bacitracin (5.4 %). Weight gain (p < 0.05) increased in AGP+ diets during post-weaning (6.5 %). However, there was no effect of AGP on weight gain of growing-finishing pigs. There was better (p < 0.05) feed conversion in pigs fed AGP+ diets in all rearing phases. Weight gain and feed conversion improved (p < 0.05) with the addition of Avilamycin, Bacitracin, and Tylosin. AGP withdrawal in the post-weaning phase increased feed costs by US$ 0.86 per animal and in growing-finishing phase the increase was US$ 3.11. Thus, pigs fed AGP+ diets have a better performance than pigs fed AGP- diets and the withdrawal of AGP increases feed costs.

Estimation of productive losses caused by withdrawal of antibiotic growth promoter from pig diets Meta-analysis

This study was designed to simulate productive and economic losses due to the withdrawal of antibiotic growth promoters (AGP) from pig diets. Articles that compared diets with AGP (AGP+) or without AGP (AGP–) for pigs were collected from electronic databases and the performance results were entered in a database. A meta-analysis was performed following the sequence: graphical analysis, correlation, and variance-covariance. The performance results observed in the meta-analysis, feed cost, and AGP costs were used to build equations to estimate the economic effect of withdrawing AGP. The database comprised 81 scientific articles containing 103 experiments totalizing 42,923 pigs. Avilamycin (24.7 %) was the most frequent AGP in the database, followed by Colistin (15.4 %), Tiamulin (11.7 %), Tylosin (8.0 %), Lincomycin (9.4 %), and Bacitracin (5.4 %). Weight gain (p < 0.05) increased in AGP+ diets during post-weaning (6.5 %). However, there was no effect of AGP on weight gain of growing-finishing pigs. There was better (p < 0.05) feed conversion in pigs fed AGP+ diets in all rearing phases. Weight gain and feed conversion improved (p < 0.05) with the addition of Avilamycin, Bacitracin, and Tylosin. AGP withdrawal in the post-weaning phase increased feed costs by US$ 0.86 per animal and in growing-finishing phase the increase was US$ 3.11. Thus, pigs fed AGP+ diets have a better performance than pigs fed AGP- diets and the withdrawal of AGP increases feed costs.(AU)

Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains

ABSTRACT: The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8g/ml for doxycycline, >4g/ml for valnemulin, 8g/ml for tiamulin, 32g/ml for tylvalosin, >64g/ml for lincomycin and >128g/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.

RESUMO: Os objetivos deste trabalho foram a caracterização de isolados de Brachyspira hyodysenteriae e avaliar os padrões de sensibilidade antimicrobiana de isolados obtidos a partir de suínos no Brasil com base no teste de concentração inibitória mínima (MIC). A MIC foi realizada em 22 isolados de B. hyodysenteriae obtidos entre 2011 a 2013 usando os seguintes antimicrobianos: tilosina, tiamulina, valnemulina, doxiciclina, lincomicina e tilvalosina. Surtos de disenteria suína foram diagnosticados com base na apresentação clínica, isolamento bacteriano, lesões macroscópicas e microscópicas, PCR duplex para B. hyodysenteriae e B. pilosicoli e sequenciamento do gene nox. Todos os valores de MIC obtidos foram consistentemente mais elevados ou igual ao ponto de corte microbiológica descrito na literatura. Os valores de MIC 90 para os fármacos testados foram de 8 g / mL para a doxiciclina, > 4 g/ml de valnemulina, 8 g / mL para a tiamulina, 32 g / ml para tilvalosina, > 64 g / ml para a lincomicina e > 128 g / ml de tilosina. Estes resultados corroboram em grande parte com os relatados na literatura. Tiamulina, doxiciclina e tilvalosina apresentaram os menores resultados de MIC. Todas as amostras submetidas à análise filogenética com base na sequência do gene nox exibiram resultados semelhantes, indicando 100% de identidade com B. hyodysenteriae. Este é o primeiro estudo que descreve o padrão MIC de B. hyodysenteriae isoladas no Brasil.

Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains / Concentração inibitória mínima de cepas Brachyspira hyodysenteriae brasileiras

The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8µg/ml for doxycycline, >4µg/ml for valnemulin, 8µg/ml for tiamulin, 32µg/ml for tylvalosin, >64µg/ml for lincomycin and >128µg/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.(AU)

Os objetivos deste trabalho foram a caracterização de isolados de Brachyspira hyodysenteriae e avaliar os padrões de sensibilidade antimicrobiana de isolados obtidos a partir de suínos no Brasil com base no teste de concentração inibitória mínima (MIC). A MIC foi realizada em 22 isolados de B. hyodysenteriae obtidos entre 2011 a 2013 usando os seguintes antimicrobianos: tilosina, tiamulina, valnemulina, doxiciclina, lincomicina e tilvalosina. Surtos de disenteria suína foram diagnosticados com base na apresentação clínica, isolamento bacteriano, lesões macroscópicas e microscópicas, PCR duplex para B. hyodysenteriae e B. pilosicoli e sequenciamento do gene nox. Todos os valores de MIC obtidos foram consistentemente mais elevados ou igual ao ponto de corte microbiológica descrito na literatura. Os valores de MIC 90 para os fármacos testados foram de 8 µg / mL para a doxiciclina, > 4 µg/ml de valnemulina, 8 µg / mL para a tiamulina, 32 µg / ml para tilvalosina, > 64 µg / ml para a lincomicina e > 128 µg / ml de tilosina. Estes resultados corroboram em grande parte com os relatados na literatura. Tiamulina, doxiciclina e tilvalosina apresentaram os menores resultados de MIC. Todas as amostras submetidas à análise filogenética com base na sequência do gene nox exibiram resultados semelhantes, indicando 100% de identidade com B. hyodysenteriae. Este é o primeiro estudo que descreve o padrão MIC de B. hyodysenteriae isoladas no Brasil.(AU)

Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains / Concentração inibitória mínima de cepas Brachyspira hyodysenteriae brasileiras

The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8µg/ml for doxycycline, >4µg/ml for valnemulin, 8µg/ml for tiamulin, 32µg/ml for tylvalosin, >64µg/ml for lincomycin and >128µg/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.(AU)

Os objetivos deste trabalho foram a caracterização de isolados de Brachyspira hyodysenteriae e avaliar os padrões de sensibilidade antimicrobiana de isolados obtidos a partir de suínos no Brasil com base no teste de concentração inibitória mínima (MIC). A MIC foi realizada em 22 isolados de B. hyodysenteriae obtidos entre 2011 a 2013 usando os seguintes antimicrobianos: tilosina, tiamulina, valnemulina, doxiciclina, lincomicina e tilvalosina. Surtos de disenteria suína foram diagnosticados com base na apresentação clínica, isolamento bacteriano, lesões macroscópicas e microscópicas, PCR duplex para B. hyodysenteriae e B. pilosicoli e sequenciamento do gene nox. Todos os valores de MIC obtidos foram consistentemente mais elevados ou igual ao ponto de corte microbiológica descrito na literatura. Os valores de MIC 90 para os fármacos testados foram de 8 µg / mL para a doxiciclina, > 4 µg/ml de valnemulina, 8 µg / mL para a tiamulina, 32 µg / ml para tilvalosina, > 64 µg / ml para a lincomicina e > 128 µg / ml de tilosina. Estes resultados corroboram em grande parte com os relatados na literatura. Tiamulina, doxiciclina e tilvalosina apresentaram os menores resultados de MIC. Todas as amostras submetidas à análise filogenética com base na sequência do gene nox exibiram resultados semelhantes, indicando 100% de identidade com B. hyodysenteriae. Este é o primeiro estudo que descreve o padrão MIC de B. hyodysenteriae isoladas no Brasil.(AU)

Antimicrobial susceptibility patterns of Brazilian Haemophilus parasuis field isolates / Perfil de susceptibilidade antimicrobiana de isolados clínicos brasileiros de Haemophilus parasuis

Haemophilus parasuis is the etiological agent of Glässer's disease (GD), an ubiquitous infection of swine characterized by systemic fibrinous polyserositis, polyarthritis and meningitis. Intensive use of antimicrobial agents in swine husbandries during the last years triggered the development of antibiotic resistances in bacterial pathogens. Thus, regular susceptibility testing is crucial to ensure efficacy of different antimicrobial agents to this porcine pathogen. In this study, 50 clinical isolates from South Brazilian pig herds were characterized and analyzed for their susceptibility to commonly used antibiotic. The identification and typing of clinical isolates was carried out by a modified indirect hemagglutination assay combined with a multiplex PCR. The susceptibility of each isolate was analyzed by broth microdilution method against a panel of 21 antimicrobial compounds. We found that field isolates are highly resistance to gentamycin, bacitracin, lincomycin and tiamulin, but sensitive to ampicillin, clindamycin, neomycin, penicillin, danofloxacin and enrofloxacin. Furthermore, an individual susceptibility analysis indicated that enrofloxacin is effective to treat clinical isolates with the exception of those classified as serovar 1. The results presented here firstly demonstrate the susceptibility of Brazilian clinical isolates of H. parasuis to antimicrobials widely used by swine veterinary practitioners and strengthen the need to perform susceptibility test prior to antibiotic therapy during GD outbreaks. In addition, because only six antimicrobial drugs (28.6%) were found effective against field isolates, a continuous surveillance of the susceptibility profile should be of major concern to the swine industry.(AU)

Haemophilus parasuis é o agente etiológico da doença de Glässer (GD), um processo infeccioso que acomete suínos e que se caracteriza por poliserosites fibrinosas sistêmicas, poliartrites e meningites. O uso intensivo de agentes antimicrobianos na produção de suínos, durante os últimos anos, tem disparado a seleção de cepas bacterianas resistentes a antibióticos. Desta maneira, a avaliação rotineira de susceptibilidade torna-se crucial para assegurar a correta seleção de um antimicrobiano eficaz contra este patógeno. Neste estudo, analisou-se a susceptibilidade antimicrobiana de 50 isolados clínicos de H. parasuis procedentes de granjas localizadas na região sul do Brasil. A identificação e tipificação dos isolados clínicos foi realizada através de uma PCR multiplex combinada com o teste de hemaglutinação indireta modificada. A susceptibilidade de cada isolado foi analisada pelo método de microdiluição em caldo utilizando-se um painel composto por 21 agentes antimicrobianos. Os resultados deste estudo indicam que as cepas clínicas de H. parasuis apresentam alta resistência à gentamicina, bacitracina, lincomicina e tiamulina, no entanto, são susceptíveis a ampicilina, clindamicina, neomicina, penicilina, enrofloxacina e danofloxacina. A análise de susceptibilidade realizada dentro de cada grupo de cepas de um mesmo sorovar indicou que a enrofloxacina é o antibiótico mais efetivo para tratar todos isolados clínicos com exceção daqueles pertencentes ao sorovar 1. Em termos gerais, neste trabalho, demonstra-se o perfil de susceptibilidade de isolados clínicos de H. parasuis aos antimicrobianos comumente utilizados pelos médicos veterinários especialistas em suínos, e reforça-se a necessidade da realização de testes de susceptibilidade antes do início da terapia com antibióticos durante surtos de DG. Além disso, como somente seis antimicrobianos (28.6%) foram efetivos contra os isolados clínicos, uma vigilância contínua do perfil de susceptibilidade aos antimicrobianos deve ser de grande preocupação para a indústria de suínos.(AU)

Antimicrobial susceptibility patterns of Brazilian Haemophilus parasuis field isolates / Perfil de susceptibilidade antimicrobiana de isolados clínicos brasileiros de Haemophilus parasuis

Haemophilus parasuis is the etiological agent of Glãsser's disease (GD), an ubiquitous infection of swine characterized by systemic fibrinous polyserositis, polyarthritis and meningitis. Intensive use of antimicrobial agents in swine husbandries during the last years triggered the development of antibiotic resistances in bacterial pathogens. Thus, regular susceptibility testing is crucial to ensure efficacy of different antimicrobial agents to this porcine pathogen. In this study, 50 clinical isolates from South Brazilian pig herds were characterized and analyzed for their susceptibility to commonly used antibiotic. The identification and typing of clinical isolates was carried out by a modified indirect hemagglutination assay combined with a multiplex PCR. The susceptibility of each isolate was analyzed by broth microdilution method against a panel of 21 antimicrobial compounds. We found that field isolates are highly resistance to gentamycin, bacitracin, lincomycin and tiamulin, but sensitive to ampicillin, clindamycin, neomycin, penicillin, danofloxacin and enrofloxacin. Furthermore, an individual susceptibility analysis indicated that enrofloxacin is effective to treat clinical isolates with the exception of those classified as serovar 1. The results presented here firstly demonstrate the susceptibility of Brazilian clinical isolates of H. parasuis to antimicrobials widely used by swine veterinary practitioners and strengthen the need to perform susceptibility test prior to antibiotic therapy during GD outbreaks. In addition, because only six antimicrobial drugs (28.6%) were found effective against field isolates, a continuous surveillance of the susceptibility profile should be of major concern to the swine industry.(AU)

Haemophilus parasuis é o agente etiológico da doença de Glãsser (GD), um processo infeccioso que acomete suínos e que se caracteriza por poliserosites fibrinosas sistêmicas, poliartrites e meningites. O uso intensivo de agentes antimicrobianos na produção de suínos, durante os últimos anos, tem disparado a seleção de cepas bacterianas resistentes a antibióticos. Desta maneira, a avaliação rotineira de susceptibilidade torna-se crucial para assegurar a correta seleção de um antimicrobiano eficaz contra este patógeno. Neste estudo, analisou-se a susceptibilidade antimicrobiana de 50 isolados clínicos de H. parasuis procedentes de granjas localizadas na região sul do Brasil. A identificação e tipificação dos isolados clínicos foi realizada através de uma PCR multiplex combinada com o teste de hemaglutinação indireta modificada. A susceptibilidade de cada isolado foi analisada pelo método de microdiluição em caldo utilizando-se um painel composto por 21 agentes antimicrobianos. Os resultados deste estudo indicam que as cepas clínicas de H. parasuis apresentam alta resistência à gentamicina, bacitracina, lincomicina e tiamulina, no entanto, são susceptíveis a ampicilina, clindamicina, neomicina, penicilina, enrofloxacina e danofloxacina. A análise de susceptibilidade realizada dentro de cada grupo de cepas de um mesmo sorovar indicou que a enrofloxacina é o antibiótico mais efetivo para tratar todos isolados clínicos com exceção daqueles pertencentes ao sorovar 1. Em termos gerais, neste trabalho, demonstra-se o perfil de susceptibilidade de isolados clínicos de H. parasuis aos antimicrobianos comumente utilizados pelos médicos veterinários especialistas em suínos, e reforça-se a necessidade da realização de testes de susceptibilidade antes do início da terapia com antibióticos durante surtos de DG. Além disso, como somente seis antimicrobianos (28.6%) foram efetivos contra os isolados clínicos, uma vigilância contínua do perfil de susceptibilidade aos antimicrobianos deve ser de grande preocupação para a indústria de suínos.(AU)

EVALUATION OF DIETARY FIBRE SOURCES ON THE PERFORMANCE AND INTESTINAL PERMEABILITY OF PIGLETS DURING NURSERY PHASE

Objetivou-se avaliar o efeito de diferentes fontes de fibras em dietas pós-desmame, associadas ao uso reduzido de ZnO e/ou GEA sobre o desempenho, permeabilidade intestinal, incidência de diarreia, concentração de E. Coli nas fezes, excreção de Zn, cobre e proteína bruta nas fezes e a porcentagem de animais medicados a primeira semana pós-desmame. Um total de 90 leitões desmamados aos 25 dias (7.84±1.71 kg), foram distribuídos em um delineamento em blocos (peso) casualizado e divididos em 5 tratamentos: T1 - Tiamulina como GEA em associação com alta dosagem de ZnO (de 2500 a 1500 ppm); T2 - GEA negativo e fibra de lignocelulose (2%) em associação com alta dosagem de ZnO; T3 - GEA negativo e fibra de lignocelulose eubiótica (2%) em associação com alta dosagem de ZnO; T4 - GEA negativo e fibra de lignocelulose em associação com dosagem reduzida de ZnO (100 ppm); T5 - GEA negativo e fibra de lignocelulose eubiótica em associação com dosagem reduzida de ZnO (100 ppm), com seis repetições e três leitões por baia. O programa nutricional foi dividido em 4 fases (pré-inicial 1: 25 a 32 dias; pré-inicial II: 33 a 39 dias; inicial I: 40 a 53 dias; e inicial II: 54 a 67 dias). Todos os dados passaram pelo teste F. Adotou-se o teste de Tukey (P < 0.05), para comparar as médias. Embora tenha havido diferença entre o consumo de ração diário (CRD) em todos os períodos (P < 0,05), os tratamentos não influenciaram no peso final dos leitões. Na primeira semana, o maior CRD foi nos animais alimentados com fibra de lignocelulose eubiótica e dosagem reduzida de ZnO (T5). O CRD dos outros tratamentos não diferiu entre si. Porém, na segunda fase de creche, os maiores resultados do CRD foram obtidos com os animais do T1, T3 e T5. Analisando a somatória nos dois últimos períodos (0-28 e 0-42 dias), o ZnO influenciou negativamente o CRD dos leitões. O menor valor de ingestão de ração foi observado nos leitões alimentados com dieta contendo fibra de lignocelulose eubiótica e alta dosagem de ZnO (T3). Houve diferenças significativas entre as fases do teste de absorção de galactose (TAG). Quando houve diferença estatística pelo teste F (P < 0.05), Os valores do TAG na segunda fase foram menores em comparação com a primeira. Assim, pode-se inferir que a função de barreira intestinal foi garantida com o uso das fibras alimentares na fase de creche, tanto em altas quanto em baixas dosagens de ZnO. No geral, os animais alimentados com doses reduzidas de ZnO nas dietas tiveram menor excreção de Zn e Cobre nas fezes. Pode-se concluir que a inclusão de fibra eubiótica de lignocelulose nas dietas de leitões na fase de creche permite a retirada total da Tiamulina 80% como melhorador de desempenho e redução de 96% do óxido de zinco como antimicrobiano, sem prejudicar o desempenho dos animais, garantindo a manutenção da função de barreira no intestino e proporcionando menor excreção fecal de Zn no meio ambiente.

This study aimed to evaluate the effect of different fiber sources in post-weaning diets, associated with reduced use of ZnO and/or GEA on performance, intestinal permeability, incidence of diarrhea, E. Coli concentration in feces, Zn excretion, copper and crude protein in feces and the percentage of animals medicated the first week after weaning. A total of 90 piglets weaned at 25 days (7.84±1.71 kg) were distributed in a randomized block design (weight) and divided into 5 treatments: T1 - Tiamulin as GEA in association with high dosage of ZnO (from 2500 to 1500 ppm); T2 - negative GEA and lignocellulose fiber (2%) in association with high dosage of ZnO; T3 - negative GEA and eubiotic lignocellulose fiber (2%) in association with high dosage of ZnO; T4 - negative GEA and lignocellulose fiber in association with reduced dosage of ZnO (100 ppm); T5 - negative GEA and eubiotic lignocellulose fiber in association with reduced dosage of ZnO (100 ppm), with six replicates and three piglets per pen. The nutritional program was divided into 4 phases (pre-initial 1: 25 to 32 days; pre-initial II: 33 to 39 days; initial I: 40 to 53 days; and initial II: 54 to 67 days). All data passed the F test. The Tukey test (P < 0.05) was used to compare the means. Although there was a difference between the average daily feed intake (ADFI) in all periods (P < 0.05), the treatments did not influence the final weight of the piglets. In the first week, the highest ADFI was in animals fed with eubiotic lignocellulose fiber and reduced ZnO dosage (T5). The ADFI of the other treatments did not differ from each other. However, in the second stage of day care, the highest ADFI results were obtained with animals from T1, T3 and T5. Analyzing the sum in the last two periods (0-28 and 0-42 days), ZnO negatively influenced the ADFI of piglets. The lowest feed intake value was observed in piglets fed a diet containing eubiotic lignocellulose fiber and high ZnO (T3). There were significant differences between the phases of the sugar absorption test (SAT). When there was statistical difference by the F test (P < 0.05), SAT values in the second phase were lower compared to the first. Thus, it can be inferred that the intestinal barrier function was guaranteed with the use of dietary fiber in the nursery phase, both in high and low doses of ZnO. In general, animals fed reduced doses of ZnO in the diets had lower excretion of Zn and copper in feces. It can be concluded that the inclusion of eubiotic lignocellulose fiber in the diets of piglets in the nursery phase allows the total withdrawal of Tiamulin 80% as a performance enhancer and a 96% reduction of zinc oxide as an antimicrobial, without harming the performance of the animals, ensuring the maintenance of the barrier function in the intestine and providing less fecal excretion of Zn in the environment.

Padronização da técnica de microdiluição em caldo e avaliação da sensibilidade antimicrobiana a óleos essenciais para isolados brasileiros de Brachyspira hyodysenteriae

O presente trabalho buscou padronizar uma nova técnica de avaliação de sensibilidade antimicrobiana da Brachyspira hyodysenteriae utilizando a técnica de microdiluição em caldo e comparando ao kit comercial VetMIC Brachy SVA. Além disso, utilizando a técnica de microdiluição em caldo avaliou-se a sensibilidade antimicrobiana de isolados brasileiros de B. hyodysenteriae aos óleos essenciais carvacrol, timol e cinamaldeído. Foram utilizadas nove cepas brasileiras, isoladas entre 2012 e 2019, e uma cepa referência. Os isolados foram plaqueados em ágar TSA enriquecido com sangue, incubadas a 37°C em anaerobiose por quatro dias, ressuspendidas em caldo Brain Heart Infusion (BHI) enriquecido com soro fetal bovino e mantidas em anaerobiose a 37°C em placas de 96 poços, com diluições seriadas dos antimicrobianos lincomicina, doxiciclina, tiamulina, valnemulina e tilosina e dos óleos essenciais carvacrol, timol e cinamaldeído. Após quatro dias, a sensibilidade antimicrobiana foi avaliada através da verificação do crescimento bacteriano, visível pela avaliação da turbidez do meio de cultivo. Para o teste comercial, foram seguidas as instruções do fabricante, adicionando 500 l da suspensão de bactérias a cada um dos poços da placa, contendo diluições seriadas dos seguintes antimicrobianos lincomicina, doxiciclina, tiamulina, tilvalosina, valnemulina e tilosina. A avaliação da sensibilidade foi realizada da mesma forma da que o teste de microdiluição. Os resultados obtidos permitem afirmar que o teste de microdiluição é um bom substituto ao kit comercial, tendo boa concordância entre eles, enquanto os óleos essenciais avaliados não apresentam boa atividade antimicrobiana in vitro, sendo necessários estudos in vivo para melhor caracterizar suas ações.

The objective of this study was to standardize a new technique to evaluate the antimicrobial sensitivity of Brachyspira hyodysenteriae using the broth microdilution test comparing it to the commercial kit VetMIC Brachy SVA. In addition, the same broth test was used to evaluate the antimicrobial sensitivity of B. hyodysenteriae for the essential oils carvacrol, thymol and cynnamaldehyde. In order to do that, nine Brazilian strains, isolated between 2012 and 2019, and a reference strain, were harvested on agar, mantained under anaerobiosis atmosphere at 37°C during four days, resuspended in Brain Heart Infusion Broth with foetal bovine serum and inoculated under anaerobiosis atmosphere at 37°C during four days in 96 wells plates, doing serial dilution of the following antimicrobials: lincomycin, doxycycline, tiamulin, valnemulin and tylosin and the essential oils carvacrol, thymol and cynnamaldehyde. After four days, the antimicrobial sensitivity was evaluated by bacterial growth, visible through the media turbidity. For the commercial kit, manufacturer instructions were followed, adding 500 l of the bacterial suspension to each plate well containing two-fold serial dilutions for lincomycin, doxycycline, tiamulin, tilvalosin, valnemulin and tylosin. The evaluation of sensitivity was performed as to the microdilution test. Our results demonstrated that the microdilution test can be a substitute to the commercial kit, having adequate similarity with each other, while the essential oils evaluated did not have satisfatory antimicrobial activity in vitro. Further in vivo studies are required to better understand their effects

Addition of intestinal alkaline phosphatase in diets and its effects on growth performance and intestinal health of weaned piglets challenged with Escherichia coli K88+

In this study, our aim was to assess the additional effect of intestinal alkaline phosphatase (IAP) in diets on growth performance, diarrhea occurrence (DO), blood metabolites, intestinal histology, relative organ weights, bacterial population counts, pH of digestive tract content, hepatic glycogen reserve (HGR), histopathological description and proinflammatory markers of piglets challenged with enterotoxigenic Escherichia coli (ETEC) K88+. A total of 64 crossbred piglets, entire male, weaned at 25-days-old with an average initial body weight of 7.168 ± 0.287 kg were allocated to a randomized complete block design consisting of four treatments repeated twice in the two blocks: control diet (negative control), control diet + antimicrobial growth promoter (AGP, 150 g of tiamulin/ton of diet), control diet + 15 mg IAP/kg of diet and control diet + 30 mg IAP/kg of diet, four replications per block with two piglets per experimental unit. All piglets were orally challenged with 6 mL of a solution containing ETEC K88+ (106 CFU/mL). Prior to the beginning of the experimental period, was determined the best microencapsulation process of IAP in a model involving adhesion and phagocytic activity of equine bronchoalveolar macrophage. In Exp. I, the variables analyzed were growth performance, DO, blood metabolites (urea, glucose and alkaline phosphatase), intestinal morphometry, relative organ weight and in vitro simulation of microencapsulated IAP on pH modulation capacity and its dilution in acidic and basic solution. At 19 experimentation days, six animals per treatment were slaughtered for data collection and biological samples. Exp. II involved the evaluation of the effect of IAP on intestinal health by bacterial populations counts in the intestinal content and adhered to mesenteric lymph node, digestive organ content pH, HGR, proinflammatory markers in the liver and intestinal epithelium and histopathological description of the intestinal epithelium. In pre-starter I phase, piglets that received 30 mg IAP added in the diet or control diet showed better feed conversion rate (P = 0.075) compared to those fed 15 mg IAP. Piglets that consumed 30 mg IAP or control diet showed greater (P = 0.004) average daily body weight gain (ADBWG) in the pre-starter II phase. Piglets fed 15 mg IAP had lower average daily feed intake (ADFI) (P = 0.033) compared to piglets with diets containing AGP. At the total period, there was a difference between treatment, in which the piglets fed 15 mg IAP showed a reduction in ADBWG (P = 0.040) and ADFI (P = 0.092). For the pre-starter II phase, there was a difference (P = 0.044) of treatment, in which the piglets that consumed the diet containing 30 mg IAP showed a 24% improvement in DO compared to the treatment with 15 mg IAP. We observed the main effect (P = 0.009), with the addition of 30 mg IAP in the post-challenge phase in decreasing piglet DO (5.56%) when compared to those receiving AGP (16.67%). For the total period, piglets that consumed 15 mg IAP showed greater (P = 0.007) DO when compared to those receiving 30 mg IAP. No differences between treatments were obtained in any of the pre- and post-challenge plasma concentration indicators. The spleen relative weight of piglet increased (P = 0.043) in response to 30 mg IAP treatment. The Enterobacteriaceae counts in the cecum content were lower (P = 0.002) in piglets that receiving 30 mg IAP compared with those for AGP treatment. Piglets fed 30 mg IAP presented lower (P = 0.007) Enterobacteriaceae count in the colon when compared to the other treatments. For the Enterobacteriaceae count adhered to the mesenteric lymph nodes (MLN), there was an increase (P = 0.006) in piglets fed diets with AGP. Piglets fed the control diet or AGP showed greater (P = 0.000) lactic acid bacteria (LAB) count in the cecum content. There was a treatment effect (P = 0.013) on LAB count in MLN, in which piglets fed with AGP or that received 30 mg IAP had a greater count when compared to those with 15 mg IAP. The experimental treatments did not influence (P > 0.05) the pH of the digestive tract contents, intestinal morphology, TNF-, COX-2 activity, TLR4 and proliferating cell nuclear antigen in the jejunum and liver, nor on HGR. Piglets that received 30 mg IAP showed a slight reduction on TNF- in jejunum (4.17 times) and liver (1.9 times) when compared to piglets in the control group or with AGP, respectively. Based on the present results, the addition of 30 mg IAP in diets improves the growth performance and attenuates the DO in piglets in the post-weaning period. In addition, the results suggest that the addition of 30 mg IAP provides an ability to mitigate intestinal injuries and maintain the homeostasis of the intestinal physiology of piglets.

In this study, our aim was to assess the additional effect of intestinal alkaline phosphatase (IAP) in diets on growth performance, diarrhea occurrence (DO), blood metabolites, intestinal histology, relative organ weights, bacterial population counts, pH of digestive tract content, hepatic glycogen reserve (HGR), histopathological description and proinflammatory markers of piglets challenged with enterotoxigenic Escherichia coli (ETEC) K88+. A total of 64 crossbred piglets, entire male, weaned at 25-days-old with an average initial body weight of 7.168 ± 0.287 kg were allocated to a randomized complete block design consisting of four treatments repeated twice in the two blocks: control diet (negative control), control diet + antimicrobial growth promoter (AGP, 150 g of tiamulin/ton of diet), control diet + 15 mg IAP/kg of diet and control diet + 30 mg IAP/kg of diet, four replications per block with two piglets per experimental unit. All piglets were orally challenged with 6 mL of a solution containing ETEC K88+ (106 CFU/mL). Prior to the beginning of the experimental period, was determined the best microencapsulation process of IAP in a model involving adhesion and phagocytic activity of equine bronchoalveolar macrophage. In Exp. I, the variables analyzed were growth performance, DO, blood metabolites (urea, glucose and alkaline phosphatase), intestinal morphometry, relative organ weight and in vitro simulation of microencapsulated IAP on pH modulation capacity and its dilution in acidic and basic solution. At 19 experimentation days, six animals per treatment were slaughtered for data collection and biological samples. Exp. II involved the evaluation of the effect of IAP on intestinal health by bacterial populations counts in the intestinal content and adhered to mesenteric lymph node, digestive organ content pH, HGR, proinflammatory markers in the liver and intestinal epithelium and histopathological description of the intestinal epithelium. In pre-starter I phase, piglets that received 30 mg IAP added in the diet or control diet showed better feed conversion rate (P = 0.075) compared to those fed 15 mg IAP. Piglets that consumed 30 mg IAP or control diet showed greater (P = 0.004) average daily body weight gain (ADBWG) in the pre-starter II phase. Piglets fed 15 mg IAP had lower average daily feed intake (ADFI) (P = 0.033) compared to piglets with diets containing AGP. At the total period, there was a difference between treatment, in which the piglets fed 15 mg IAP showed a reduction in ADBWG (P = 0.040) and ADFI (P = 0.092). For the pre-starter II phase, there was a difference (P = 0.044) of treatment, in which the piglets that consumed the diet containing 30 mg IAP showed a 24% improvement in DO compared to the treatment with 15 mg IAP. We observed the main effect (P = 0.009), with the addition of 30 mg IAP in the post-challenge phase in decreasing piglet DO (5.56%) when compared to those receiving AGP (16.67%). For the total period, piglets that consumed 15 mg IAP showed greater (P = 0.007) DO when compared to those receiving 30 mg IAP. No differences between treatments were obtained in any of the pre- and post-challenge plasma concentration indicators. The spleen relative weight of piglet increased (P = 0.043) in response to 30 mg IAP treatment. The Enterobacteriaceae counts in the cecum content were lower (P = 0.002) in piglets that receiving 30 mg IAP compared with those for AGP treatment. Piglets fed 30 mg IAP presented lower (P = 0.007) Enterobacteriaceae count in the colon when compared to the other treatments. For the Enterobacteriaceae count adhered to the mesenteric lymph nodes (MLN), there was an increase (P = 0.006) in piglets fed diets with AGP. Piglets fed the control diet or AGP showed greater (P = 0.000) lactic acid bacteria (LAB) count in the cecum content. There was a treatment effect (P = 0.013) on LAB count in MLN, in which piglets fed with AGP or that received 30 mg IAP had a greater count when compared to those with 15 mg IAP. The experimental treatments did not influence (P > 0.05) the pH of the digestive tract contents, intestinal morphology, TNF-, COX-2 activity, TLR4 and proliferating cell nuclear antigen in the jejunum and liver, nor on HGR. Piglets that received 30 mg IAP showed a slight reduction on TNF- in jejunum (4.17 times) and liver (1.9 times) when compared to piglets in the control group or with AGP, respectively. Based on the present results, the addition of 30 mg IAP in diets improves the growth performance and attenuates the DO in piglets in the post-weaning period. In addition, the results suggest that the addition of 30 mg IAP provides an ability to mitigate intestinal injuries and maintain the homeostasis of the intestinal physiology of piglets.

USO COMBINADO DE PROBIÓTICO E ANTIMICROBIANO MELHORADOR DE DESEMPENHO EM DIETAS DE LEITÕES NA FASE DE CRECHE

Mudanças relacionadas ao desmame são fatores estressantes e podem causa redução do crescimento dos leitões, principalmente pela incidência de diarreia. Considerando as limitações ao uso de antimicrobianos melhoradores de desempenho, diferentes estratégias têm sido propostas para manter o crescimento e desempenho animal. Neste sentido, objetivou-se avaliar os efeitos do uso de probiótico (Bacillus amyloliquefaciens) na dieta de leitões em fase de creche, associado ou não ao uso de antimicrobiano melhorador de desempenho (tiamulina). Foram distribuídos 84 leitões com idade média de 28 dias em delineamento em blocos casualizados e esquema fatorial 2 x 2, quatro tratamentos, correspondentes à inclusão ou não de antibiótico melhorador de desempenho (tiamulina 80% 150ppm) e o uso de probiótico (Bacillus amyloliquefaciens). Os tratamentos adotados foram: T1 dieta basal (DB, controle); T2 DB + antimicrobiano; T3 DB + probiótico; T4 DB + antimicrobiano + probiótico. Calculou-se o ganho de peso diário (GPD), o consumo e a conversão alimentar (CA). O escore fecal foi monitorado conforme o método proposto por Guedes et al. Amostras de fezes foram coletadas para análise de presença e contagem de Escherichia coli (Quinn et al.). As análises estatísticas foram realizadas utilizando o software R e diferenças consideradas significativas para P<0,05. Para dados não-paramétricos, utilizou-se o teste de Friedman e o teste de Tukey para os demais. Os dados absolutos de contagem microbiológica foram logaritmizados e analisados de forma descritiva. O consumo médio diário de ração foi afetado pelo uso do antimicrobiano, enquanto a utilização do probiótico não resultou em efeito significativo. Ganho de peso e conversão alimentar não foram afetados pelo uso de antimicrobiano ou probiótico. O escore de diarreia foi afetado significativamente na fase final, com menores escores para animais alimentados com antimicrobiano e probiótico. Na avaliação descritiva da contagem de E. coli, houve tendência de maior contagem bacteriana fecal ao longo do período experimental em todos os tratamentos, de forma mais destacada nas amostras provenientes dos animais que não ingeriram probiótico. A utilização de probiótico (B. amyloliquefaciens) é estratégia válida para substituir o uso de antimicrobianos para suínos em fase de creche. A adição do probiótico melhorou o consumo e desempenho dos leitões nas fases iniciais de creche.

Changes related to weaning are stressful factors and may cause reduced piglet growth, mainly due to the incidence of diarrhea. Considering the limitations to the use of antimicrobial performance enhancers, different strategies were proposed to maintain animal growth and performance. The objective of this study was to evaluate the effects of the use of probiotic (Bacillus amyloliquefaciens) on weaned piglets diet, associated or not with the use of antimicrobial performance enhancer (tiamulin). A total of 84 piglets with a mean age of 28 days were randomized in blocks and a factorial scheme 2 x 2, with four treatments, corresponding to the inclusion or not of performance improvement antibiotic (tiamulin 80% 150ppm) and probiotic (Bacillus amyloliquefaciens). The treatments adopted were: T1 - basal diet (DB, control); T2 - DB + antimicrobial; T3 - DB + probiotic; T4 - DB + antimicrobial + probiotic. Avarage daily gain (ADG), feed intake and feed efficiency were calculated. The fecal score was monitored according to the method proposed by Guedes et al. Feces samples were collected for presence and counting analysis of Escherichia coli (Quinn et al.). Statistical analyzes were performed using software R and differences considered significant for P <0.05. For non-parametric data it was used the Friedman test and the Tukey test were used for the others. The absolute data of microbiological counting were logarithmized and analyzed in a descriptive way. The average daily feed intake was affected by the use of antimicrobial, while the use of probiotic did not result in significant effect. Weight gain and feed conversion were not affected by the use of antimicrobial or probiotic. The diarrhea score was significantly affected in the final phase, with lower scores for animals fed with antimicrobial and probiotic. In the descriptive evaluation of the E. coli count, there was a trend of higher fecal bacterial count over the experimental period in all treatments, more prominently in the samples from the animals that did not take probiotic. The use of probiotics (B. amyloliquefaciens) is a valid strategy to replace the use of antimicrobials for weaned pigs. The addition of probiotic improved piglet consumption and performance in the early stages of life.

INTOXICAÇÃO POR SALINOMICINA EM SUÍNOS NO ESTADO DE SANTA CATARINA

CARVALHO, Amanda Queiroz. Intoxicação por salinomicina em suínos no Estado de Santa Catarina. 2019. 68p. Tese (Doutorado em Ciência Animal Área de Concentração: Saúde Animal). Universidade do Estado de Santa Catarina. Programa de Pós-Graduação em Ciência Animal. Lages, 2019. A presente tese teve por objetivo estudar os casos de miopatia tóxica que ocorrem em suínos, no estado de Santa Catarina, relacionados ao uso de salinomicina na ração associado ao uso concomitante de antibióticos. Foram descritos dois casos espontâneos de intoxicação por salinomicina, o primeiro deles associado ao uso de tiamulina e o segundo ao florfenicol. Em ambos os casos os animais apresentaram sinais clínicos locomotores caracterizados por incoordenação motora, andar rígido, relutância ao movimento, fraqueza e tremores musculares, dispneia, depressão e decúbito, permanecendo em posição de cão sentado ou com abdução dos membros pélvicos, e quando em estação, apoiavam-se nas pinças dos cascos. O achado macroscópico mais relevante observado durante a necropsia foi palidez leve dos músculos dos membros pélvicos. Os principais achados histopatológicos foram áreas multifocais de degeneração hialina e necrose e necrose flocular acentuadas as vezes associado a fagocitose de fibras e formação de miotubulos. Essas lesões foram mais intensas nos músculos longissimus dorsi e semimembranoso. O diagnóstico de miopatia tóxica secundária a intoxicação por ionóforo baseou-se nos aspectos epidemiológicos e no quadro clínico-lesional. Para estudar a interação do florfenicol na intoxicação por salinomicina foram conduzidos dois experimentos. O primeiro teve o intuito de verificar a capacidade do florfenicol influenciar na toxicidade da salinomicina, e foi denominado Intoxicação aguda por salinomicina e florfenicol. O segundo teve a finalidade de verificar o potencial acumulativo da salinomicina, e foi denominado Intoxicação crônica por salinomicina. A intoxicação por salinomicina e florfenicol foi realizada utilizando 12 suínos, divididos em 4 grupos com 3 animais cada, tratados por 16 dias com rações contendo: Grupo 1: sem aditivos. Grupo 2: 50ppm de salinomicina. Grupo 3: 40ppm de florfenicol. Grupo 4: 50ppm de salinomicina e 40ppm de florfenicol. Dois animais do grupo 3 adoeceram e desenvolveram o quadro clínico lesiona de miopatia tóxica. A intoxicação aguda foi reproduzida a partir da ingestão de 24, 67mg/kg/PV de salinomicina e 19,74 mg/kg/PV de florfenicol, comprovando que o florfenicol foi capaz de influenciar na toxicidade de salinomicina. A intoxicação crônica por salinomicina foi realizada, com 20 suínos, com peso médio de 36,28kg, divididos em 5 grupos com 4 animais cada, alojados em baias individuais de alvenaria. Os animais foram alimentados por 42 dias com rações contendo salinomicina nas seguintes dosagens: Grupo 1: 25 ppm de salinomicina; Grupo 2: 50 ppm de salinomicina; Grupo 3: 75 ppm de salinomicina; Grupo 4: 100 ppm de salinomicina e Grupo 5: 150 ppm de salinomicina. Nesse experimento nenhum animal apresentou sintomatologia clínica, a menor ingestão foi de 40,69 mg/kg, enquanto a maior foi de 289,79 mg/kg. O consumo de ração não foi inibido pela alta ingestão de salinomicina e os suínos apresentaram ganho médio de peso de 46,64 kg em 42 dias, com peso final médio de 82,92 kg. Concluindo-se que nas doses utilizadas, a salinomicina não demonstrou potencial acumulativo nos suínos.

CARVALHO, Amanda Queiroz. Salinomycin intoxication in pigs in the State of Santa Catarina. 2019. 68p. Thesis (Doctorate in Animal Science Area: Animal Health). Santa Catarina State University. Post Graduate Program in Animal Science. Lages, 2019. This study aimed to study cases of toxic myopathy that occurs in Santa Catarina state, related to the use of salinomycin associated with antibiotics. Two spontaneous cases of salinomycin poisoning were described, the first associated with the use of tiamulin and the second with florfenicol. In both cases the animals presented locomotor clinical signs characterized by motor incoordination, rigid walking, reluctance to movement, muscle weakness and tremors, dyspnea, depression and decubitus, remaining in sitting dog position or with abduction of the pelvic limbs, and when in season, they rested on the hooves' tongs. The most relevant macroscopic finding observed during autopsy was mild pallor of the pelvic limb muscles. The main histopathological findings were multifocal areas of hyaline degeneration and marked floccular necrosis, sometimes associated with fiber phagocytosis and myotubule formation. These lesions were more intense in the longissimus dorsi and semimembranosus muscles. The diagnosis of toxic myopathy secondary to ionophore poisoning was based on the epidemiological aspects and the clinical-lesion picture. To study the interaction of florfenicol in salinomycin poisoning, two experiments were conducted. The first was intended to verify the ability of florfenicol to influence salinomycin toxicity and was called Acute salinomycin and florfenicol poisoning. The second was intended to verify the cumulative potential of salinomycin and was called Chronic Salinomycin Poisoning. Salinomycin and florfenicol poisoning was performed using 12 pigs, divided into 4 groups with 3 animals each, treated for 16 days with diets containing: Group 1: no additives. Group 2: 50ppm salinomycin. Group 3: 40ppm florfenicol. Group 4: 50ppm salinomycin and 40ppm florfenicol. Two animals from group 3 became got sick and developed the injured clinical condition of toxic myopathy. Acute intoxication was reproduced from ingestion of 24.67mg/kg/lw of salinomycin and 19.74 mg/kg/lw of florfenicol, proving that florfenicol was able to influence salinomycin toxicity. Chronic salinomycin poisoning was performed with 20 pigs weighing 36.28kg, divided into 5 groups with 4 animals each, housed in individual pen. The animals were fed for 42 days with diets containing salinomycin at the following dosages: Group 1: 25 ppm salinomycin; Group 2: 50 ppm salinomycin; Group 3: 75 ppm salinomycin; Group 4: 100 ppm salinomycin and Group 5: 150 ppm salinomycin. In this experiment no animal presented clinical symptoms, the lowest intake was 40.69 mg/kg, while the highest was 289.79 mg/kg. Feed intake was not inhibited by high salinomycin intake and pigs had average weight gain of 46.64 kg in 42 days, with average final weight of 82.92 kg. In conclusion, at the doses used, salinomycin did not show accumulative potential in pigs.

Sensibilidade antimicrobiana in vitro de isolados brasileiros de Lawsonia intracellularis.

Enterite Proliferativa Suína, causada pela bactéria Lawsonia intracellularis, é uma doença entérica de distribuição mundial, e de alta prevalência. Os sinais clínicos observados são diarreia, redução na conversão alimentar e no ganho de peso diário. A forma mais efetiva de tratamento é a terapia com antimicrobianos. Portanto, objetivo deste estudo foi determinar a concentração mínima inibitória (MIC) in vitro de ciprofloxacina, lincomicina e tiamulina em dois isolados brasileiros de L. intracellularis. Como L. intracellularis é um microrganismo intracelular obrigatório foi realizada avaliação de concentração inibitória mínima para as atividades extracelular e intracelular. A ciprofloxacina e a tiamulina apresentaram os melhores resultados de atividades extracelulares e intracelulares inibindo o crescimento de ambos os isolados brasileiros de L. intracellularis, apesar da ciprofloxacina ter apresentado concentração moderada nas duas duplicatas testadas para o isolado BRPHE02-E8 (variando de 8 e 4 g/mL). O mesmo não ocorreu para lincomicina, que apresentou concentrações elevadas ( 128 g/mL) em todos os testes realizados e para todos os isolados testados. Portanto, os dois isolados brasileiros de L. intracellularis testados nesse estudo têm maior sensibilidade in vitro a ciprofloxacina e tiamulina que a lincomicina.

Porcine Proliferative Enteritis, caused by the bacterium Lawsonia intracellularis, is an enteric disease with worldwide distribution. Several studies showed high prevalence of the disease worldwide. The clinical signs observed are diarrhea, weight loss, emaciation accompanied by reduction in feed conversion and in daily weight gain. The most effective form of treatment is antimicrobial therapy. Therefore, the objective of this study was to determine the minimum inhibitory concentration in vitro of ciprofloxacin, lincomycin and tiamulin against L. intracellularis Brazilian isolates. As L. intracellularis is an obligate intracellular microorganism, a minimum inhibitory concentration evaluation was performed for extracellular and intracellular activities of the antimicrobials. The extracellular and intracellular activities for ciprofloxacin and tiamulin showed the best results. It was shown that the lower concentrations of the active principles were able to inhibit the growth of the bacterium for both isolates, although the ciprofloxacin presented moderate concentration in the two duplicates tested for the isolate BRPHE02-E8 (varying of 8 and 4 g / mL). The same did not occur with lincomycin, which had high concentrations ( 128 g / mL) in all the tests performed and for all tested isolates. Therefore, the two brazilian isolates of L. intracellularis tested in this study had greater sensitivity to ciprofloxacin and tiamulin when compared to lincomycin.

Caracterização de Salmonella enterica subespécie enterica sorovar Cholerasuis provenientes de suínos no Brasil

Salmonella Choleraesuis é o agente causador de um quadro septicêmico em suínos que pode apresentar altas taxas de mortalidade nos animais infectados. No presente estudo foram avaliadas 93 estirpes de S. Choleraesuis provenientes de suínos com sinais clínicos de infecção. Foram avaliadas estirpes originadas de sete granjas localizadas nos Estados de São Paulo, Paraná, Santa Catarina e Minas Gerais obtidas durantes os anos de 2015, 2016 e 2017. As estirpes de Salmonella foram submetidas a reação em cadeia pela polimerase para confirmação do sorovar pela amplificação do gene fliC, em seguida foram caracterizadas quanto ao perfil de resistência a antimicrobianos e a caracterização genotípica pelo polimorfismo do comprimento de fragmentos amplificados (AFLP). A determinação do perfil de resistência a antimicrobianos revelou que as 93 estirpes foram resistentes a penicilina, doxiciclina, sulfadimetoxina, clindamicina, tilosina, tilmicosina e tiamulina, sendo, portanto, todas multirresistentes. Os antimicrobianos com menores taxas de resistência foram cefitiofur (0%), marbofloxacina (1,1%), neomicina (10,8%) e enrofloxacina (18,3%). As estirpes foram discriminadas em 17 perfis de resistência diferentes, o perfil mais frequente reuniu 39 estirpes (42%) resistentes a penicilina, ampicilina, doxiciclina, oxitetraciclina, florfenicol, sulfadimetoxina, gentamicina, tulatromicina, tilosina, tilmicosina, tiamulina e clindamicina. A análise das estirpes pelo AFLP indicou todas as 93 estirpes foram agrupadas em um único perfil com mais de 94% de similaridade. A partir dos dados obtidos é possível verificar que as estirpes de S. Choleraesuis isoladas de suínos apresentaram baixa variabilidade genética e alta frequência de resistência aos antimicrobianos mais usados em suinocultura.

Salmonella Choleraesuis is the causative agent of septicemia in pigs and may present high mortality rates in infected animals. In the present study, 93 strains of S. choleraesuis from pigs with clinical signs of infection were evaluated. Strains from seven farms located in the states of São Paulo, Paraná, Santa Catarina and Minas Gerais obtained during the years 2015, 2016 and 2017 were evaluated. Salmonella strains were submitted to polymerase chain reaction for confirmation of serovar by amplification of the fliC gene were then characterized for antimicrobial resistance profile and genotype characterization by amplified fragment length polymorphism (AFLP). The determination of the antimicrobial resistance profile revealed that the 93 strains were resistant to penicillin, doxycycline, sulfadimethoxine, clindamycin, tylosin, tilmicosin and tiamulin, and were therefore multiresistant. The antimicrobials with the lowest resistance rates were cefitiofur (0%), marbofloxacin (1.1%), neomycin (10.8%) and enrofloxacin (18.3%). The strains were discriminated in 17 different resistance profiles, the most frequent profile consisted of 39 strains (42%) resistant to penicillin, ampicillin, doxycycline, oxytetracycline, florfenicol, sulfadimetoxin, gentamicin, tulathromycin, tylosin, tilmicosin, tiamulin and clindamycin. Analysis of the strains by AFLP indicated that all 93 strains were grouped into a single profile with more than 94% similarity. From the data obtained it is possible to verify that the strains of S. Choleraesuis isolated from pigs presented low genetic variability and high frequency of resistance to the antimicrobials most used in swine production systems.

Live performance and processing yields of broilers fed diets with tiamulin and salinomycin combinations

A study was conducted with the objective of evaluating the combined application of tiamulin (TIA) and salinomycin (SAL) in broiler diets fed from 1 to 42 d of age. One thousand and two hundred Cobb x Cobb 500 male broilers were housed in 48 floor pens and fed corn-soybean meal diets containing 66 ppm of SAL combined or not with TIA at 30 or 20 and 20 or 15 ppm, respectively, in the starter (1-21 d) and grower feeds (22-42 d); however, TIA was withdrawn from the feeds 7 days before slaughter. The experimental design was completely randomized with 3 treatments and 16 replicates of 25 birds each. Broilers were weekly evaluated for live performance whereas carcass yield, abdominal fat and commercial cuts were assessed at 42 d using 6 birds randomly taken from each pen. Results obtained at the end of the study demonstrated that body weight gain was not affected (P > 0.05) by the treatments, whereas feed intake was reduced (P 0.05) and feed conversion was improved (P 0.05) for birds on diets containing TIA at 30/20 and 20/15 ppm, respectively. Carcass yield, abdominal fat, and commercial parts were not affected (P > 0.05) by the treatments. Live performance and post-slaughter yields data obtained in this study did not indicate that combinations of TIA with SAL could be detrimental. In fact, an improvement in feed conversion was observed at the lowest dose of TIA.

Live performance and processing yields of broilers fed diets with tiamulin and salinomycin combinations

A study was conducted with the objective of evaluating the combined application of tiamulin (TIA) and salinomycin (SAL) in broiler diets fed from 1 to 42 d of age. One thousand and two hundred Cobb x Cobb 500 male broilers were housed in 48 floor pens and fed corn-soybean meal diets containing 66 ppm of SAL combined or not with TIA at 30 or 20 and 20 or 15 ppm, respectively, in the starter (1-21 d) and grower feeds (22-42 d); however, TIA was withdrawn from the feeds 7 days before slaughter. The experimental design was completely randomized with 3 treatments and 16 replicates of 25 birds each. Broilers were weekly evaluated for live performance whereas carcass yield, abdominal fat and commercial cuts were assessed at 42 d using 6 birds randomly taken from each pen. Results obtained at the end of the study demonstrated that body weight gain was not affected (P > 0.05) by the treatments, whereas feed intake was reduced (P 0.05) and feed conversion was improved (P 0.05) for birds on diets containing TIA at 30/20 and 20/15 ppm, respectively. Carcass yield, abdominal fat, and commercial parts were not affected (P > 0.05) by the treatments. Live performance and post-slaughter yields data obtained in this study did not indicate that combinations of TIA with SAL could be detrimental. In fact, an improvement in feed conversion was observed at the lowest dose of TIA.

Caracterização genotípica e fenotípica de cepas de Escherichia coli associadas à diarreia pós-desmame em suínos

A Escherichia coli é um dos principais agentes envolvidos na síndrome da diarreia pós-desmame em suínos, sendo a infecção de difícil controle devido à elevada capacidade deste agente em desenvolver e disseminar mecanismos de resistência aos antimicrobianos utilizados para o tratamento da doença. No presente estudo foi estabelecido o perfil de virulência de cepas de E. coli isoladas de 621 leitões com sintomas de diarreia na fase de creche (21 a 40 dias de vida), provenientes de 52 granjas de suínos no Brasil. Foram selecionadas 148 cepas de E. coli, positivas para fímbria F4 e /ou F18 e destas foi determinado o perfil de resistência à antimicrobianos por determinação da concentração inibitória mínima para os seguintes antimicrobianos: ampicilina, clindamicina, clortetraciclina, danofloxacina, enrofloxacina, florfenicol, gentamicina, neomicina, oxitetraciclina, sulfadimetoxina, espectinomicina, trimetoprima / sulfametoxazole, tiamulina, tilmicosina, tulatromicina, tilosina, ceftiofur e enrofloxacina. Dos 621 animais observados, 321 animais foram positivos para pelo menos um fator de virulência. Das cepas estudadas, todas as 148 foram resistentes a tilosina, clindamicina, tiamulina, tilmicosina e sulfadimetoxina. A frequência de cepas resistentes foi elevada também para o oxitetraciclina, clortetraciclina, danofloxacina, ampicilina e ao florfenicol. Considerando-se o fato de 100% das cepas terem apresentado resistência a mais de três classes de antimicrobianos pode-se concluir que todas as cepas de E.coli do presente estudo foram multirresistentes sendo frequente a resistência aos principais antimicrobianos utilizados na terapia da diarreia em leitões de creche.

Escherichia coli is one of the agents involved in the syndrome of post-weaning diarrhea in swine. The infection is difficult to control because of high ability of this agent to develop and spread antimicrobial resistance mechanisms against commonly used antibiotics. This study has as goal determine the virulence profile of E. coli strains isolated of 621 piglets with diarrhea symptoms in the nursery with 21-40 days of age, from 52 pig farms in Brazil. Of the isolated strains, we selected 148 strains of E. coli, positive for F4 fimbriae and / or F18 and these were tested for antimicrobial resistance for determining the minimum inhibitory concentration for the following antibiotics: ampicillin, clindamycin, chlortetracycline, danofloxacin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline, sulfadimethoxin, spectinomycin, trimethoprim / sulfamethoxazole, tiamulin, tilmicosin, tulathromycin, tylosin, ceftiofur and enrofloxacin. Of the 621 observed animals 321 animals were positive for at least one virulence factor. Of the studied strains, all 148 were resistant to tylosin, clindamycin, tiamulin, tilmicosin and sulfadimethoxin. The frequency of resistant strains was also high for oxytetracycline, chlortetracycline, danofloxacin, ampicillin and florfenicol. Considering the fact that 100% of the strains have shown resistance to more than three classes of antimicrobials can be concluded that all E. coli strains in this study were multidrug-resistant and are frequent the resistance to the main antimicrobials used in therapy of diarrhea in nursery pigs.

Caracterização fenotípica e genotípica de isolados de Bordetella bronchiseptica provenientes de diferentes espécies animais

Bordetella bronchiseptica é um agente respiratório zoonótico comumente encontrado em diversars espécies animais domésticos como cães, gatos, coelhos, suínos, aves e equinos. As infecções em humanos ocorrem ocasionalmente, sendo descritas com maior freqüência em indivíduos imunocomprometidos, mas relatos de casos de doença em adultos saudáveis e crianças têm aumentado. O presente estudo teve como objetivos determinar o perfil de resistência antimicrobiana de cepas de B. bronchiseptica isoladas de cães, gatos, coelhos e suínos, caracterizar as cepas pela eletroforese em campo pulsado (PFGE), e comparar os resultados obtidos com os dados epidemiológicos. Foram avaliadas 145 cepas e estas apresentaram 100% de resistência a ampicilina, penicilina, espectinomicina, clindamicina, tiamulina e tilosina. Taxas de resistência superiores a 95% das cepas foram observadas frente a tilmicosina, danofloxacina e ceftiofur. Os antimicrobianos com menores taxas de resistência foram enrofloxacina (2,1%) e clortetraciclina (11%). As cepas isoladas de coelhos apresentaram menores taxas de resistência que as de suínos e de animais de companhia. A caracterização das cepas pela PFGE permitiu a separação de acordo com as espécies de origem em diferentes pulsotipos. A caracterização do agente, principalmente no que se refere à resistência a antimicrobianos, será de grande utilidade para os veterinários no controle das infecções pelo mesmo em suínos, animais de companhia e coelhos, visto que os dados sobre este agente etiológico no Brasil são escassos.

Bordetella bronchiseptica is a zoonotic respiratory agent commonly found in domestic animals as dogs, cats, rabbit, swine, birds and horses. Infections in humans occur rarely and have been described more frequently in immunocompromised individuals, but reports of cases of illness in healthy adults and children have increased. This study aims to characterize the resistance profile of B. bronchiseptica strains isolated from dogs, cats, rabbits and pigs and evaluate the strains by pulsed field gel electrophoresis (PFGE), comparing the results with epidemiological data. From 145 strains tested 100% presented resistance to ampicillin, penicillin, spectinomycin, clindamycin, tiamulin and tylosin. Resistance rates higher than 95% were found against tilmicosin, danofloxacin and ceftiofur. The antimicrobials with lower resistance rates were enrofloxacin (2.1%) and chlortetracycline (11%). Strains isolated from rabbits presented low resistance rates when compared with swine and pet animals. The PFGE analysis separated the strains according specie of origin in different pulsotypes. The agent characterization, mainly in relation with antimicrobial resistance will be of great help to veterinarians in control of infections in swine, pets and rabbits, since data about this bacteria in Brazil are rare.