Resultado da pesquisa (210)

Termo utilizado na pesquisa Leite

#1 - Identification of enteropathogenic Escherichia coli as the cause of mastitis in cows from Brazil

Abstract in English:

Escherichia coli is recognized as one of the main microorganisms responsible for triggering clinical mastitis, a disease that causes considerable economic losses in the dairy industry. In this context, this study aimed to identify E. coli isolates present in individual milk samples collected from cows diagnosed with clinical mastitis from various regions of Brazil. Additionally, through polymerase chain reaction (PCR), the presence of virulence genes eae, bfpB, escN, aatA, aggR, ipaH, stx1, stx2, est, and eltA was investigated; all associated with the pathotypes of diarrheagenic Escherichia coli (DEC). As an integral part of the study, a comprehensive assessment of the sensitivity profile of the isolates to 11 different antimicrobials widely used in mastitis treatment was also conducted. A total of 198 milk samples were collected from cows diagnosed with clinical mastitis. Among these samples, 12 isolates (6.07%) demonstrated bacterial growth greater than three Colony-Forming Units (CFU) when grown on MacConkey agar medium and morphological characteristics of E. coli. The disc-diffusion test was used to evaluate the susceptibility of these isolates to antimicrobials, and the most predominant resistance was observed concerning streptomycin and tetracycline, affecting 16.67% of the strains analyzed. Notably, all isolates investigated did not demonstrate the presence of the genes eae, aatA, aggR, ipaH, stx1, stx2, est, and eltA. These results indicate that these isolates do not fit the pathotypes known as diarrheagenic Escherichia coli (DEC). However, one of the isolates tested was positive for the bfpB and escN genes. The detection of resistant E. coli associated with clinical mastitis points to possible gaps in the treatment of the disease. Additionally, the presence of resistance genes in E. coli strains indicates the potential to transmit these genes between animals and, perhaps, along the food chain.

Abstract in Portuguese:

Escherichia coli é reconhecida como um dos principais microrganismos responsáveis pelo desencadeamento da mastite clínica, doença que causa perdas econômicas consideráveis na indústria de laticínios. Neste contexto, este estudo teve como objetivo principal a identificação de isolados de E. coli presentes em amostras individuais de leite coletadas de vacas com diagnóstico de mastite clínica, de diversas regiões do Brasil. Adicionalmente, por reação em cadeia da polimerase (PCR), foi investigada a presença dos genes de virulência eae, bfpB, escN, aatA, aggR, ipaH, stx1, stx2, est e eltA, todos associados aos patótipos de E. coli diarreiogênica (DEC). Como parte integrante do estudo, foi realizada uma avaliação abrangente do perfil de sensibilidade dos isolados a 11 antimicrobianos diferentes amplamente utilizados no tratamento da mastite. Foram coletadas 198 amostras de leite de vacas com diagnóstico de mastite clínica. Dentre essas amostras, 12 isolados (6,07%) demonstraram crescimento bacteriano superior a três Unidades Formadoras de Colônia (UFC) quando cultivadas em meio ágar MacConkey e características morfológicas de E. coli. Para avaliar a suscetibilidade desses isolados aos antimicrobianos foi utilizado o teste de disco-difusão, sendo observada a resistência mais predominante em relação à estreptomicina e à tetraciclina, afetando 16,67% das cepas analisadas. É relevante ressaltar que todos os isolados investigados não demonstraram a presença dos genes eae, aatA, aggR, ipaH, stx1, stx2, est e eltA. Estes resultados indicam que estes isolados não se enquadram nos patótipos conhecidos como Escherichia coli diarreiogénica (DEC). Porém, um dos isolados testados apresentou positividade para os genes bfpB e escN. A detecção de E. coli resistente associada à mastite clínica aponta para possíveis lacunas no tratamento da doença. Além disso, a presença de genes de resistência em estirpes de E. coli indica a capacidade potencial de transmitir estes genes entre animais e talvez ao longo da cadeia alimentar.


#2 - Feline application/inflammation-associated sarcoma: Gross aspects and histomorphological

Abstract in English:

Feline injection-site sarcomas in felines account for more than 40% of cutaneous and subcutaneous neoplasms in felines. The present study aimed to describe the macroscopic and histomorphological findings of feline application/injection sarcomas. Samples from 31 feline tumors with a history of feline application/inflammation sarcoma were re-evaluated regarding histological subtype, mitotic index and score, depth of tissue invasion, and presence of inflammation considering the location, intensity and predominant cell types. Of the 31 samples from felines diagnosed with sarcoma at the application/inflammation site, 87.15% were cats with no defined breed (NDB), with a mean age of 8.5 years. The predominant anatomical sites were the back and flank/abdomen, both with 29% (9/31), and the prevalent histological subtype was fibrosarcoma at 77.4% (24/31), followed by anaplastic giant cell sarcoma at 12.9% (4/31) and myxosarcoma 9.6% (3/31). The histological grade with the highest number of cases was III (51.6%), followed by Grade II (35.4%) and I (12.9%). The mean of the longest axis measurements varied between the different tumor grades without being significant, with the average being 2.5±2.79cm in Grade I tumors and 3.2±2.28cm in Grade II tumors. and 4.68±2.07cm in Grade III tumors. Necrosis was observed in 74.2% of tumors. The tissue inflammation score was mild to moderate in 58% of cases and severe in 32.2%, with lymphocytic and lymphoplasmacytic infiltrates being prevalent, with 25.8% each, followed by lymphoplasmohistiocytic with 22.6%. The infiltration depth was 38.7% in muscle tissue, followed by 32.2% in the subcutaneous tissue. Pleomorphism was accentuated in 51.6%. Desmoplasia was moderate in 45.1%. Satellite nodules were present in 29% of cases, and 19.4% had macrophages with intracytoplasmic content suggestive of adjuvants. Surgical margins were infiltrated (M1) in 48.4% and narrowed in 25.8% (M2). The anatomical locations observed were different from those recommended by the Vaccine-Associated Feline Sarcoma Task Force (VAFST); in most cases, the adjuvanted macrophage was not present. From this data, we can suggest that sarcomas in felines are not only correlated to the vaccine application, corroborating the hypothesis that any material, whether liquid or solid, and any chronic inflammatory process in the subcutaneous tissue of cats can induce the entity if they are predisposed to do so. The detailed histomorphological data evaluated in this study were key points and provided important information about tumor behavior, being a tool for clinical-oncological decision-making.

Abstract in Portuguese:

Feline injection-site sarcomas in felines account for more than 40% of cutaneous and subcutaneous neoplasms in felines. The present study aimed to describe the macroscopic and histomorphological findings of feline application/injection sarcomas. Samples from 31 feline tumors with a history of feline application/inflammation sarcoma were re-evaluated regarding histological subtype, mitotic index and score, depth of tissue invasion, and presence of inflammation considering the location, intensity and predominant cell types. Of the 31 samples from felines diagnosed with sarcoma at the application/inflammation site, 87.15% were cats with no defined breed (NDB), with a mean age of 8.5 years. The predominant anatomical sites were the back and flank/abdomen, both with 29% (9/31), and the prevalent histological subtype was fibrosarcoma at 77.4% (24/31), followed by anaplastic giant cell sarcoma at 12.9% (4/31) and myxosarcoma 9.6% (3/31). The histological grade with the highest number of cases was III (51.6%), followed by Grade II (35.4%) and I (12.9%). The mean of the longest axis measurements varied between the different tumor grades without being significant, with the average being 2.5±2.79cm in Grade I tumors and 3.2±2.28cm in Grade II tumors. and 4.68±2.07cm in Grade III tumors. Necrosis was observed in 74.2% of tumors. The tissue inflammation score was mild to moderate in 58% of cases and severe in 32.2%, with lymphocytic and lymphoplasmacytic infiltrates being prevalent, with 25.8% each, followed by lymphoplasmohistiocytic with 22.6%. The infiltration depth was 38.7% in muscle tissue, followed by 32.2% in the subcutaneous tissue. Pleomorphism was accentuated in 51.6%. Desmoplasia was moderate in 45.1%. Satellite nodules were present in 29% of cases, and 19.4% had macrophages with intracytoplasmic content suggestive of adjuvants. Surgical margins were infiltrated (M1) in 48.4% and narrowed in 25.8% (M2). The anatomical locations observed were different from those recommended by the Vaccine-Associated Feline Sarcoma Task Force (VAFST); in most cases, the adjuvanted macrophage was not present. From this data, we can suggest that sarcomas in felines are not only correlated to the vaccine application, corroborating the hypothesis that any material, whether liquid or solid, and any chronic inflammatory process in the subcutaneous tissue of cats can induce the entity if they are predisposed to do so. The detailed histomorphological data evaluated in this study were key points and provided important information about tumor behavior, being a tool for clinical-oncological decision-making.


#3 - Micromineral concentrations (copper, cobalt, iron, molybdenum and zinc) in the liver of dairy cows from Campos Gerais Region, Paraná state, Brazil

Abstract in English:

This study collected samples from 50 Holstein cows, most intensively bred, and from the Campos Gerais region, Paraná, with an average milk production of 30.21L/day. Samples of the liver, spleen and lymph nodes were collected to determine the levels of copper, cobalt, iron, molybdenum and zinc. Spleen and lymph nodes were subjected to histological analysis and evaluation of the degree of hemosiderosis. The average concentrations of copper (495.05ppm), molybdenum (4.19ppm), and zinc (274.49ppm) were higher than those established for the bovines. For cobalt 26% of the animals presented levels below the established level, which characterized cobalt deficiency. Only iron (299.12ppm) exhibited an adequate average level. Histopathologically hemosiderosis was observed mainly in the spleen (78%) and less frequently in the lymph nodes (20%). The observation of hemosiderin in the spleen and lymph nodes is not related to copper deficiency. Still it may be related to high levels of molybdenum, zinc, iron, or other undetermined causes.

Abstract in Portuguese:

Para este estudo foram coletadas amostras de 50 vacas, da raça Holandesa, a maior parte criada intensivamente e oriunda da região dos Campos Gerais/PR, com média individual de produção de leite de 30,21L/dia. Foram coletadas amostras de fígado, baço e linfonodos para determinação dos níveis de cobre (Cu), cobalto (Co), ferro (Fe), molibdênio (Mo) e zinco (Zn). Baço e linfonodo foram submetidos à análise histológica e avaliação do grau de hemossiderose. A média das concentrações de Cu (495,05ppm), Mo (4,19ppm) e Zn (274,49ppm) encontrava-se acima dos níveis estabelecidos para bovinos. Para o Co, observou-se que 26% dos animais apresentaram níveis abaixo do estabelecido, o que caracterizou deficiência de Co. Apenas o Fe (299,12ppm) apresentou níveis médios adequados. Na histopatologia, hemossiderose foi observada, principalmente no baço (78%) e com menos frequência nos linfonodos (20%). A observação de hemossiderina no baço e linfonodos não está relacionada à deficiência de Cu, porém pode estar relacionada a elevados níveis de Mo, Zn e Fe ou a outras causas não determinadas.


#4 - Epidemiological, anatomopathological, and immunophenotypical aspects of cutaneous lymphomas in dogs

Abstract in English:

Cutaneous lymphomas are uncommon tumors in dogs that can occur as epitheliotropic and non-epitheliotropic types. The epitheliotropic type comprises three, already well established, distinct clinicopathological presentations. However, the non-epitheliotropic lymphoma, despite its poor characterization, represents a heterogeneous group of not yet correlated presentations that can mimic different skin tumors, configuring a diagnostic challenge. Therefore, this study’s main aim was to establish whether there is a correlation between the macroscopic presentation and the histological subtypes of cutaneous non-epitheliotropic lymphoma in the population of dogs involved in this study. Additionally, we aimed to determine the prevalence of each type and histological subtype of canine cutaneous lymphoma and describe the epidemiological and anatomopathological characteristics of the presented cases. From a total of 38 cases of cutaneous lymphoma diagnosed in dogs, 17 (44.7%) were considered as epitheliotropic and 21 (55.3%) as non-epitheliotropic. From the 17 cases of cutaneous epitheliotropic lymphoma, 13 (34.2%) and four (10.5%) were subclassified as mycosis fungoides and pagetoid reticulosis, respectively. The cases of cutaneous non-epitheliotropic lymphoma included were: anaplastic large T-cell lymphoma (ALTCL – 9/21, 23.9%), peripheral T-cell lymphoma, unspecified (PTCL-NOS – 4/21, 10.5%), subcutaneous panniculitis-like T-cell lymphoma (SPTCL – 4/21, 10.5%), diffuse large B-cell lymphoma – immunoblastic type (DLBCL – 2/21, 5.2%), lymphomatoid granulomatosis (LYG – 1/21, 2.6%), and marginal zone lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT) - lymphoplasmacytic variant (1/21, 2.6%). Based on the anatomopathological findings, it was possible to infer that when faced with multiple, nodular or placoid skin lesions, predominantly on the trunk and limbs, the diagnosis is more likely to be consistent with ALTCL. Whereas, with solitary skin nodules or plaques, PTCL-NOS will be the most frequently observed histological type. When these lesions are exclusively located in the subcutaneous tissue, one should first think about SPTCL and, more rarely, DLBCL. Regarding to epitheliotropic cutaneous lymphomas, the most commonly observed type in dogs is the cutaneous form of mycosis fungoides, especially in the pre-mycotic and mycotic phases. We hope that this information can assist veterinary clinicians and pathologists in their diagnostic routines and contribute to the characterization of non-epitheliotropic cutaneous lymphomas in the canine species.

Abstract in Portuguese:

Linfomas cutâneos são tumores incomuns em cães que podem ocorrer sob as formas epiteliotrópica e não epiteliotrópica. A forma epiteliotrópica compreende três apresentações clinicopatológicas distintas já bem estabelecidas. Contudo, a forma não epiteliotrópica, apesar de ser reconhecida, é menos caracterizada, representando um grupo heterogêneo de apresentações ainda não correlatas e que aparentemente podem mimetizar diferentes tumores de pele, configurando um desafio diagnóstico. Assim, o objetivo principal deste trabalho foi tentar estabelecer se há correlação entre a apresentação macroscópica e os subtipos histológicos de linfoma cutâneo não epiteliotrópico da população de cães em estudo. Adicionalmente, objetivou-se determinar a prevalência de cada tipo e subtipo histológico de linfoma cutâneo canino, e ainda, descrever as características epidemiológicas e anatomopatológicas dos casos. Foram incluídos 38 casos de linfomas cutâneos caninos, desses, 17 (44,7%) eram epiteliotrópicos e 21 (55,3%) eram não epiteliotrópicos. Dos 17 casos de linfomas epiteliotrópicos, 13 (34,2%) foram subclassificados como micose fungoide e quatro (10,5%) como reticulose pagetoide. Os casos de linfomas cutâneos não epiteliotrópicos foram subclassificados como: linfoma anaplásico de grandes células T (ALTCL – 9/21; 23,9%), linfoma de células T periféricas inespecífico (PTCL-NOS – 4/21; 10,5%), linfoma de células T semelhante à paniculite subcutânea (SPTCL – 4/21; 10,5%), linfoma difuso de grandes células B – variante imunoblástica (DLBCL – 2/21; 5,2%), granulomatose linfomatoide (LYG – 1/21; 2,6%) e linfoma da zona marginal (MZL) do tecido linfoide associado à mucosa (MALT) – variante linfoplasmocítica (1/21; 2,6%). Com base nos achados anatomopatológicos foi possível inferir que diante da suspeita de linfoma cutâneo não epiteliotrópico em cães, ao se deparar com lesões cutâneas múltiplas, nodulares ou placoides e predominantes em tronco e membros, é mais provável que na histopatologia o diagnóstico seja consistente com ALTCL. Por outro lado, perante nódulos ou placas cutâneas solitárias, PTCL-NOS será o tipo histológico mais frequentemente visto. E quando essas lesões estiverem exclusivamente localizadas no tecido subcutâneo, deve-se primeiramente pensar em SPTCL e, mais raramente, em DLBCL. No que se refere aos linfomas cutâneos epiteliotrópicos, a forma cutânea da micose fungoide é a mais comumente observada em cães, em especial, nas fases pré-micótica e micótica. Espera-se essas informações possam auxiliar médicos veterinários clínicos e patologistas em suas rotinas diagnósticas, bem como, contribuir para a caracterização dos linfomas cutâneos não epiteliotrópicos na espécie canina.


#5 - Detection of paratuberculosis in dairy cows from southern Brazil

Abstract in English:

Bovine paratuberculosis causes chronic, incurable diarrhea and weight loss, resulting in decreased cattle production. The disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), an obligate intracellular mycobactin-dependent mycobacterium that replicates slowly in the host and has heightened environmental resistance. In countries where the disease is found and the damage has been quantified, direct and indirect economic losses are extremely high. Local epidemiological data is of paramount importance for the implementation of control programs. Our objective was to verify whether paratuberculosis is present in commercial dairy herds in different mesoregions of RS. Therefore, a prospective, cross-sectional and observational study was performed on dairy cattle from five mesoregions of the RS state, Brazil. Milk samples taken from individual cows on commercial farms were tested using indirect ELISA tests and classified as negative, suspicious, or positive. In herds containing at least one positive cow, we conducted convenience sampling of feces directly from the rectal ampulla to identify MAP through PCR. Of the 362 cows tested, 20 were seroreactive for paratuberculosis from two mesoregions. The PCR tests were all positive; cows with a negative ELISA and positive PCR results probably indicate that the MAP was ingested and eliminated without causing infection. We found that paratuberculosis is likely endemic in the northwest and northeast mesoregions.

Abstract in Portuguese:

A paratuberculose bovina causa diarreia crônica e incurável, perda de peso e resulta em diminuição da produção. A doença é causada pelo Mycobacterium avium subsp. paratuberculosis (MAP), micobactéria intracelular obrigatória, dependente de micobactina, que se replica lentamente no hospedeiro e possui elevada resistência ambiental. Nos países onde a doença é encontrada e os danos foram quantificados, as perdas econômicas diretas e indiretas são extremamente altas. Os dados epidemiológicos locais são de suma importância para a implementação de programas de controle. Nosso objetivo foi verificar se a paratuberculose está presente em rebanhos leiteiros comerciais em diferentes mesorregiões do RS. Para tanto, foi realizado um estudo prospectivo, transversal e observacional em bovinos leiteiros de cinco mesorregiões do estado do RS, Brasil. Amostras de leite individuais, provenientes de vacas leiteiras de fazendas comerciais foram testadas com ELISA indireto e classificadas como negativas, suspeitas ou positivas. Em rebanhos contendo pelo menos uma vaca positiva, realizamos amostragem por conveniência, em que foram coletadas fezes diretamente da ampola retal, para identificar MAP por meio da PCR. Das 362 vacas testadas, 20 foram sororreativas para paratuberculose, oriundas de duas mesorregiões. Os testes de PCR foram todos positivos. Vacas com resultado negativo no teste ELISA e PCR positivo provavelmente indicam que o MAP foi ingerido e eliminado sem causar infecção. Sugere-se que a paratuberculose é provavelmente endêmica nas mesorregiões noroeste e nordeste.


#6 - Refractory feline sporotrichosis: a comparative analysis on the clinical, histopathological, and cytopathological aspects

Abstract in English:

Sporotrichosis is a chronic fungal infection caused by Sporothrix species. The occurrence of cases that are resistant to long-term treatment, especially in the nasal planum of cats, emphasizes the importance of studying its pathogenesis. The purpose of this study was to analyze and compare the inflammatory process of cutaneous lesions of feline refractory sporotrichosis to clinical aspects through cytopathological and histopathological examination. Moreover, the study included 13 cats with cutaneous lesions that had been resistant to itraconazole treatment for more than a year. Cutaneous lesions samples were collected for cytopathological, histopathological, and fungal culture analyses. Tissue fragments were processed and stained with hematoxylin-eosin (HE) and Grocott methenamine silver (GMS). Further, two clinical presentations had the highest occurrence: the localized cutaneous form in animals with good general condition and stable disease (n=9, 69.2%) and the disseminated cutaneous form in cats with poor general condition (n=4, 30.8%). In cats with refractory sporotrichosis, the nasal planum (84.6%) was the most common location of lesions. In the cytopathological study, cats with fewer than two lesions and in good general condition (n=9, 69.2%) showed absence or mild yeast intensity (up to 5 yeasts per field), lower intensity of macrophages and neutrophils, and higher intensity of epithelioid cells, lymphocytes, plasma cells, and eosinophils. On the other hand, (n=4, 30.8%) of the cats with disseminated sporotrichosis and a poor general condition had a marked intensity of yeasts, which were mostly phagocytosed by an increased number of macrophages and neutrophils. Of those animals with good general condition, the majority (n=6, 66.7%) had higher eosinophil intensity. In histopathology, malformed suppurative granuloma was the predominant type (n=9, 69.2%) in feline sporotrichosis lesions, followed by well-formed granulomas (n=4, 30.8%). Malformed granulomas showed mild to moderate fungal intensity (55.6%) in animals with good general condition and localized lesions while marked fungal intensity (44.4%) in cats with the disseminated form of the disease and poor general condition. Well-formed granulomas (n=4, 30.7%) had mild to moderate intensity of fungal load, and 75% of the animals with this type of granuloma had only one lesion and were in good general condition. Long-term itraconazole treatment in these cats with refractory sporotrichosis can keep the infection under control and localized lesions stable; however, fungus reactivation can occur, resulting in an exuberant and inefficient immune response.

Abstract in Portuguese:

A esporotricose é uma infecção fúngica crônica causada por espécies do gênero Sporothrix. A ocorrência de casos refratários ao tratamento de longo prazo, especialmente na região nasal de gatos, alerta para a importância do estudo de sua patogênese. Este estudo teve como objetivo analisar o processo inflamatório das lesões cutâneas de esporotricose felina refratária ao tratamento, por meio de exames citopatológico e histopalógico, e comparar com aspectos clínicos. Treze gatos com lesões cutâneas refratárias ao tratamento com Itraconazol por mais de um ano foram incluídos no estudo. Amostras de lesões cutâneas foram coletadas para análises citopatológicas, histopatológicas e cultura fúngica. Fragmentos de tecidos foram processados e corados pela hematoxilina-eosina (HE) e Prata Metenamina de Grocott (GMS). Duas apresentações clínicas tiveram maior ocorrência: a forma localizada cutânea em animais com bom estado geral e doença estável (n=9, 69,2%); e a forma disseminada cutânea em gatos com estado geral ruim (n=4, 30,8%). A região nasal (84,6%) foi a localização mais frequente das lesões nos gatos com esporotricose refratária ao tratamento. No estudo citopatológico, felinos com menos de duas lesões, e em bom estado geral, (n=9, 69,2%) revelaram ausência ou leve intensidade de leveduras (até 5 leveduras por campo), menor intensidade de macrófagos e neutrófilos, e maior intensidade de células epitelióides, linfócitos, plasmócitos e eosinófilos. Enquanto, (n=4, 30,8%) dos felinos que apresentavam a forma disseminada da esporotricose associada a um estado geral ruim, revelaram acentuada intensidade de leveduras em sua maioria fagocitadas por acentuado número de macrófagos e neutrófilos. Dos animais com bom estado geral, a maioria (n=6, 66,7%) apresentava maior intensidade de eosinófilos. Na histopatologia, o granuloma supurativo mal formado foi o tipo predominante (n=9, 69,2%) nas lesões de esporotricose felina, e (n=4, 30,8%) foram de granulomas bem formados. Granulomas mal formados apresentaram leve a moderada intensidade fúngica (55,6%) nos animais com bom estado geral e lesões localizadas, e acentuada intensidade fúngica (44,4%) nos gatos com a forma disseminada da doença e estado geral ruim. Granulomas bem formados (n=4, 30,7%) apresentaram leve a moderada intensidade de carga fúngica, sendo 75% dos animais com esse tipo de granuloma com apenas uma lesão e bom estadogeral. O tratamento de longo prazo com itraconazol, nesses gatos com esporotricose refratária, pode manter a infecção controlada e lesões localizadas estáveis de forma temporária, contudo a reativação do fungo pode ocorrer levando a uma resposta imunológica exuberante e ineficiente.


#7 - Species identification and antimicrobial susceptibility profile of bacteria associated with cow mastitis in southern Brazil

Abstract in English:

Bovine mastitis is the most common disease in dairy cattle and responsible for economic losses in the milk industry. The present study aimed to identify the main species and to evaluate the antimicrobial susceptibility of bacterial isolates from cow herds with mastitis in dairy farms from southern Brazil. A total of 107 milk samples were collected from different cow herds in one important dairy producing region in southern Brazil, including farms located in ten cities from the Northeast region in the Rio Grande do Sul state. Bacterial strains were isolated and submitted to presumptive identification by classical bacteriological methods. Bacterial species were also identified by MALDI-TOF MS and antimicrobial susceptibility testing was performed with 12 antimicrobials commonly used in dairy farms. Fifty-one bacterial strains were isolated and the presumptive identification demonstrated the occurrence of Staphylococcus spp. (82.3%), Bacillus spp. (3.9%), Klebsiella spp. (3.9%), Streptococcus spp. (3.9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) and Serratia sp. (2%). Forty-one isolates were successfully identified in the MALDI-TOF analysis, including 35 isolates from eleven different bacterial species. Importantly, there were eight different Staphylococcus species, with a high frequency of Staphylococcus chromogenes (48.6%) and Staphylococcus aureus (20%). Overall, bacterial isolates demonstrated resistance to penicillin (46.3%), tetracycline (39%), amoxicillin (36.6%), ampicillin (34.1%) and sulfamethoxazole/trimethoprim (31.7%). Enrofloxacin was the unique antimicrobial that all isolates were susceptible. In addition, there were six multidrug resistant isolates (five S. chromogenes and one S. aureus). This study highlights that bacterial pathogens with resistance to several antimicrobials were identified in cows from dairy farms in a very important milk producing region located in southern Brazil. Microbial identification of the bovine mastitis pathogens and determination of the antimicrobial profile is necessary for the rational use of the medicines.

Abstract in Portuguese:

A mastite bovina é a doença mais comum em gado leiteiro e responsável por perdas econômicas na indústria de laticínios. O presente estudo teve como objetivo identificar as principais espécies e avaliar a suscetibilidade antimicrobiana de isolados bacterianos de rebanhos bovinos com mastite em fazendas leiteiras no sul do Brasil. Um total de 107 amostras de leite foram coletadas em diferentes rebanhos bovinos em uma importante região produtora de leite do sul do Brasil, incluindo fazendas localizadas em 10 cidades da região Nordeste do estado do Rio Grande do Sul. As cepas bacterianas foram isoladas e submetidas à identificação presuntiva por métodos bacteriológicos clássicos. A identificação bacteriana foi confirmada por MALDI-TOF MS e o teste de sensibilidade antimicrobiana foi realizado com antimicrobianos comumente usados em fazendas leiteiras. Cinquenta e uma cepas bacterianas foram isoladas e a identificação presuntiva demonstrou a ocorrência de Staphylococcus spp. (82,3%), Bacillus spp. (3,9%), Klebsiella spp. (3,9%), Streptococcus spp. (3,9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) e Serratia sp. (2%). Os 41 isolados foram identificados com sucesso na análise MALDI-TOF, incluindo 35 isolados de onze espécies bacterianas diferentes. É importante ressaltar que houve a ocorrência de oito espécies diferentes de Staphylococcus, com alta frequência de Staphylococcus chromogenes (48,6%) e Staphylococcus aureus (20%). No geral, os isolados bacterianos tiveram alta resistência à penicilina (46,3%), tetraciclina (39%), amoxicilina (36,6%), ampicilina (34,1%) e sulfametoxazol/trimetoprima (31,7%). A enrofloxacina foi o único antimicrobiano que todos os isolados foram suscetíveis. Além disso, havia seis isolados multirresistentes (cinco S. chromogenes e um S. aureus). Este estudo destaca que os patógenos bacterianos com resistência aos antimicrobianos estão presentes em fazendas leiteiras de subsistência em uma importante região produtora no sul do Brasil. É necessário o monitoramento constante dos patógenos da mastite bovina e a determinação de seu perfil antimicrobiano para o uso racional dos medicamentos.


#8 - Copper deficiency in dairy goats and kids

Abstract in English:

The clinical, pathological and reproductive aspects of an outbreak of copper deficiency in dairy goats and kids from the semiarid region of Pernambuco, Brazil are described. Ten adult dairy goats with clinical signs of deficiency and four kids presenting enzootic ataxia born from copper deficient does were separated from the herd, and examined. In the dairy goats, the average serum concentration of copper was 6.1±2.8mmol/L and iron was 39.5±8.2mmol/L. In kids, the average serum concentration of copper was 3.8±0.9mmol/L and iron was 38.5±4.1mmol/L. Clinical signs in dairy goats consisted of pale mucous membranes, anemia, emaciation, diarrhea, achromotrichia, brittle hair and alopecia. The main reproductive alterations consisted of prolonged anestrus, embryonic resorption and high indices of retained placenta. The kids born from copper deficient dairy goats were weak, and presented neonatal or late ataxia until 70 days of life. Six dairy goats and four kids were necropsied. Most ovaries examined were small, firm and did not present viable follicles on their surface. Microscopically, there was reduction of viable follicles in addition to disorganization of follicular and stromal structures, with marked follicular atresia. Microscopically, changes in kids with enzootic ataxia consisted of neuronal chromatolysis and axonal degeneration, mainly in neurons of the spinal cord. In this study, the source of high iron was not identified, but it is known that outbreaks of copper deficiency can occur due to excess iron intake, mainly when adequate mineral supplementation is not provided for the goat herds.

Abstract in Portuguese:

Descrevem-se os aspectos clínicos, patológicos e reprodutivos de um surto de deficiência de cobre em cabras leiteiras e em cabritos da região semiárida de Pernambuco, Brasil. Dez cabras leiteiras adultas com sinais clínicos de deficiência de cobre e quatro cabritos com ataxia enzoótica nascidos dessas cabras foram separados do rebanho e examinados. Nas cabras leiteiras, a concentração média de cobre sérico foi de 6,1±2,8mmol/L e a concentração média de ferro sérico foi de 39,5±8,2mmol/L. Nos cabritos, a concentração média de cobre sérico foi de 3,8±0,9mmol/L e a concentração média de ferro sérico foi de 38,5±4,1mmol/L. Os sinais clínicos nas cabras consistiram em mucosas pálidas, anemia, diarreia, acromotriquia, pelos opacos e quebradiços e alopecia. As principais alterações reprodutivas consistiram em anestro prolongado, reabsorção embrionária e aumento da taxa de retenção de placenta. Os cabritos nascidos vivos dessas cabras nasceram fracos, com ataxia neonatal ou desenvolveram ataxia tardia em até 70 dias de vida. Seis cabras leiteiras e quatro cabritos foram necropsiados. Nas cabras, a maioria dos ovários examinados macroscopicamente eram pequenos, firmes e não apresentavam folículos viáveis ​​em sua superfície. Microscopicamente, houve redução de folículos viáveis, além de desorganização das estruturas foliculares, com marcada atresia folicular. Macroscopicamente não foram observadas alterações nos cabritos com ataxia enzoótica. As lesões histológicas observadas nesses cabritos consistiram em cromatólise neuronal e degeneração axonal, principalmente em neurônios da medula espinhal. Neste estudo a fonte dos altos teores de ferro no soro não foi identificada, mas sabe-se que surtos de deficiência de cobre podem ocorrer devido ao excesso de ingestão de ferro, principalmente quando não é fornecida suplementação mineral adequada para os rebanhos caprinos.


#9 - Metabolic imbalances, hoof injuries, and metabolic profile of high-producing Holstein × Gir cows showing lameness

Abstract in English:

This study attempted to determine the associations between metabolic imbalances and lameness or hoof injuries in high-producing Holstein × Gir cows, and to determine whether the metabolic profile affects the occurrence of lameness. Eighty cows were followed from -60 to 60 days relative to calving and hoof injuries were reported on days -60, 7 and 60. Locomotion score (LS), body condition score (BCS), the concentrations of non-esterified fatty acids, β-hydroxybutyrate, glucose, cholesterol, albumin, total protein, blood urea nitrogen (BUN), calcium, phosphorus, and magnesium, and the activity of aspartate aminotransferase were determined at days -42, -21, -7, 0, 7, 21 and 42. The McNemar and Chi-square tests were used to compare frequencies of lameness and hoof injuries over time and to verify the associations between lameness, BCS, hoof injuries, and metabolic disorders. Two-way repeated measures ANOVA was used considering groups (non-lame × lame cows) and variations of BCS and metabolites over time. Lameness and hoof injuries increased between days -60 (20% and 66.3%) and 60 (44.7% and 98.6%). Excessive postpartum loss of BCS (P=0.017) and subclinical hypocalcemia (P=0.012) were associated with lameness on day 60. In general, the metabolic profile did not differ between lame and non-lame cows but cholesterol, albumin, BUN and magnesium concentrations were higher in non-lame cows. The postpartum decrease in BCS can affect the occurrence of lameness, and the metabolic profile of lame cows shows little difference from that of non-lame cows.

Abstract in Portuguese:

Este estudo objetivou verificar as associações entre desequilíbrios metabólicos e claudicação ou lesões nos cascos em vacas mestiças Holandesa × Gir de alta produção e determinar se o perfil metabólico afeta a ocorrência de claudicação. Oitenta vacas foram acompanhadas de -60 a 60 dias em relação ao parto e as lesões nos cascos foram avaliadas nos dias -60, 7 e 60. O escore de locomoção (EL), o escore de condição corporal (ECC), as concentrações de ácidos graxos não esterificados, β-hidroxibutirato, glicose, colesterol, albumina, proteína total, nitrogênio ureico no sangue (BUN), cálcio, fósforo e magnésio e a atividade da aspartato aminotransferase foram determinados nos dias -42, -21, -7, 0, 7, 21 e 42. Os testes de McNemar e de Qui-quadrado foram empregados para comparar as frequências de claudicação e de lesões nos cascos ao longo do tempo e para verificar as associações entre claudicação, ECC, lesões nos cascos e distúrbios metabólicos. A análise de variâncias de medidas repetidas bifatorial foi usada considerando-se grupos (vacas com claudicação × vacas sem claudicação) e variações de BCS e de metabólitos ao longo do tempo. A claudicação e as lesões nos cascos aumentaram entre os dias -60 (20% e 66,3%) e 60 (44,7% e 98,6%). A perda excessiva de ECC no pós-parto (P=0,017) e a hipocalcemia subclínica ao parto (P=0,012) foram associadas com claudicação no dia 60. Em geral, o perfil metabólico não diferiu entre vacas com e sem claudicação, mas as concentrações de colesterol, albumina, BUN e magnésio foram maiores em vacas sem claudicação. A redução do ECC no periodo pós-parto pode afetar a ocorrência de claudicação, e o perfil metabólico das vacas claudicantes apresenta pouca diferença em relação ao das vacas não claudicantes.


#10 - Efficacy of antimicrobial therapy in association with vaccination on the bacteriological cure of subclinical mastitis caused by Staphylococcus aureus in lactating cows

Abstract in English:

The objective of this study was to evaluate the efficacy of the antibiotic therapy associated with vaccination on the microbiological cure rate of subclinical mastitis caused by Staphylococcus aureus in lactating dairy cows. A total of five herds, from which 72 cows (120 mammary quarters - MQ) were diagnosed with S. aureus subclinical mastitis, were included in this study. Cows were randomly allocated to one of three treatment groups: a) Control (no treatment); b) ATB (antibiotic therapy); and c) ATB+VAC (antibiotic therapy plus vaccination against S. aureus). Intramammary treatment consisted of twice-daily infusion of ampicillin 75mg + cloxacillin 200mg, for 5 days. Parenteral treatment was done by injection of a single dose (7.5mg/kg) of enrofloxacin, on the first day of the treatment protocol. Vaccinated cows received three doses of a commercial vaccine 14 days before treatment (d-14), on the first day of treatment protocol (d1), and 14 days after the treatment protocol (d+14). Non-treated cows had a lower cure rate (0.06) than cows treated with ATB (0.84) and ATB+VAC (0.85). No difference in cure rate was observed between cows treated with ATB and ATB+VAC. On the other hand, vaccinated cows had lower somatic cell count (SCC) after 28 days of the treatment protocols (4.76 log10) than non-treated cows (5.37 log10). In conclusion, treatment with intramammary ampicillin and cloxacillin, associated with intramuscular enrofloxacin presented a high cure rate for SCM caused by S. aureus during lactation. The use of vaccination against S. aureus in association with antibiotic therapy did not increase the cure rate of MQ during lactation, but it was effective in reducing the SCC when compared to non-treated MQ. Although to ensure that the decrease of the SCC in ATB+VAC group was associated with the vaccination, the study should have included an additional group of only vaccinated cows, without antimicrobial therapy, with was not done in the present study, and therefore is one of the limitations of the experimental protocol used.

Abstract in Portuguese:

O objetivo deste estudo foi avaliar a eficácia da antibioticoterapia associada à vacinação sobre a taxa de cura microbiológica de mastite subclínica causada por Staphylococcus aureus em vacas leiteiras em lactação. Foram selecionados 5 rebanhos, dos quais 72 vacas (120 quartos mamários, QM) foram diagnosticadas com mastite subclínica por S. aureus e foram alocadas aleatoriamente em um de três grupos de tratamento: a) Controle (sem tratamento); b) ATB (antibioticoterapia); e c) ATB+VAC (antibioticoterapia mais vacinação contra S. aureus). O tratamento intramamário consistiu em infusão de ampicilina 75 mg + cloxacilina 200 mg duas vezes ao dia, durante 5 dias. O tratamento parenteral foi feito por injeção de uma dose única (7,5 mg/kg) de enrofloxacina, no primeiro dia do protocolo de tratamento. As vacas vacinadas receberam três doses de uma vacina comercial, 14 dias antes do tratamento (d-14), no primeiro dia do protocolo de tratamento (d1) e 14 dias após o protocolo de tratamento (d+14). A taxa de cura das vacas não tratadas foi menor (0,06) do que das vacas tratadas com ATB (0,84) e ATB+VAC (0,85). Não foi observada diferença de taxa de cura entre vacas tratadas com ATB e ATB+VAC. Por outro lado, as vacas vacinadas apresentaram menor a contagem de células somáticas (CCS) após 28 dias de tratamento (4,76 log10) do que em vacas não tratadas (5,37 log10). Em conclusão, o tratamento com ampicilina e cloxacilina intramamária, associados à enrofloxacina intramuscular, apresentou alta taxa de cura para MSC causada por S. aureus durante a lactação. A utilização da vacinação contra S. aureus associada à antibioticoterapia não aumentou a taxa de cura dos QM durante a lactação, mas foi eficaz na redução do CCS quando comparada à QM não tratados. Entretanto, para ter certeza que a diminuição da CCS no grupo ATB+VAC estivesse associada à vacinação, o estudo deveria ter incluído um grupo adicional de apenas vacas vacinadas, sem terapia antimicrobiana, o que não foi feito no presente estudo e, portanto, é um das limitações do protocolo experimental utilizado.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV