Mastectomia a campo em ruminantes - aspectos cirúrgicos e clínico-patológicos / Field mastectomy in ruminants - surgical and clinicopathological aspects

Background: We report the case of 3 cows, 1 ewe, and 1 doe, with chronic mastitis and which underwent a mastectomy. All animals had a history of mastitis, edema with purulent secretion in the udder region, areas of abscess formation, fibrosis, hypogalactia, and agalactia. The animals had already been treated with systemic antibiotic therapy and anti-inflammatory drugs without response. The objective of this work is to describe the surgical and clinicopathological aspects of performing a radical mastectomy in the field in 3 cows and 1 ewe, and a partial mastectomy in a doe, with both procedures performed successfully and considered efficient to maintain the survival of the affected animals, in addition to being economically viable. Cases: In all animals reported in the study, a general and a specific clinical examination were performed, where on palpation of the udder were observed an increase in the region of the mammary apparatus, fluid fluctuation, areas of fibrosis with increased stiffness, and loss of udder functionality. In the case of the doe, there was a functional teat, which was preserved during the surgical procedure. Radical mastectomy was performed in 3 cows and 1 ewe, and the doe underwent a partial mastectomy, with preservation of the functional teat. All animals have fasted for food and water for 48 h. In cows, the anesthetic protocol consisted of 2% xylazine hydrochloride [0.15 mg/kg, intramuscularly (IM)], followed by an epidural block in the lumbosacral region with 2% lidocaine hydrochloride [10 mL]. The midazolam hydrochloride [0.1 mg/kg, intravenously (IV)] and 2% xylazine hydrochloride [0.05 mg/kg, IM] were administered to the ewe and the doe, also associated with lumbosacral epidural anesthesia with 2% lidocaine hydrochloride [5 mL]. The animals were positioned in the right lateral decubitus position and the entire abdominal and udder region were shaved and sanitized for the surgical procedures of radical mastectomy and partial mastectomy, with the use of degerming and topical povidone-iodine. The postoperative period consisted of penicillin-based antibiotic therapy associated with streptomycin [24,000 IU/kg, IM, 10 consecutive days] and flunixin meglumine [2 mg/kg, IM, 3 consecutive days] in cows; enrofloxacin [2.5 mg/kg, IM, 7 consecutive days] and flunixin meglumine [0.5 mg/kg, IM, 5 consecutive days] in the ewe; oxytetracycline [10 mg/kg, IM, 5 applications on alternate days] and flunixin meglumine [0.5 mg/kg, IM, 3 consecutive days] in the doe. In all animals, the cleaning of the surgical wound was performed daily with 10% topical Povidone-iodine and Permethrin ointment, for 14 days, when the stitches were removed. Discussion: The choice of the surgical procedure resulted in improvement of the clinical conditions and increased survival of all animals, and in the case of the doe, partial mastectomy contributed to the preservation of the functional teat, preserving its productive capacity. All anesthetic protocols used and the anatomical positioning of the animals were satisfactory for performing the procedures. Although they are techniques described in the literature with great blood loss, especially in cows, blood transfusion was not required in any of the animals. The stitches were removed 14 days after the surgical procedures, and the surgical wound was completely healed.

Real-time polymerase chain reaction for detection and enumeration of Staphylococcus aureus and Streptococccus agalactiae using different milk samplings

The objective of the present study was to evaluate the qPCR for detection and enumeration of Staphylococcus aureus and Streptococcus agalactiae using different milk samplings in comparison to the conventional microbiology. Four dairy herds with a history of subclinical mastitis caused by S. aureus and S. agalactiae were selected. Sampling approach included milk samples from bulk tank (BT), cow level (composite samples, CO), and mammary quarter level (MQ) from 785 lactating cows. Three consecutive monthly milk samplings were carried out, totaling 3347 MQ milk samples, 912 CO, and 12 from BT. All collected milk samples were subjected to conventional microbiology and qPCR for detection and enumeration of S. aureus and S. agalactiae. The qPCR showed 71.5% of diagnostic sensitivity for S. aureus isolated from MQ milk samples, 71.8% for CO, and 50% for BT milk samples compared with conventional microbiology methodology. Taken together, the diagnostic sensitivity for S. agalactiae isolated from MQ milk samples was 90.2, 87.7 for CO, and 90.9% for BT milk samples. In general, the qPCR methodology enabled the detection of S. aureus and S. agalactiae, regardless of the type of milk sampling. The direct use of milk samples to estimate the counting of S. aureus by qPCR demonstrated lower sensitivity than the counting of S. agalactiae, which can be explained by the pathogen infection dynamics and differences in milk sample type.

Deeper exploration of inflammatory cell populations in milk to monitor udder health in dairy cows

The present study explored the predictive values of milk leukocyte differentials (MLD) as a basis for improving the diagnosis of intramammary infections (IMIs) and subclinical mastitis. Quarter milk samples were collected for bacteriological analysis, quarter somatic cell count (qSCC), and MLD. The MLD were assessed using the cytospin technique, direct microscopic smears, and flow cytometry. The predictive values of each single leukocyte population and useful potential indices that could better reflect immune complexity were also calculated. Changes in the percentage of any leukocyte alone failed to substantially improve the predictive value of qSCC in diagnosing IMIs. Although certain parameters increased the area under the receiver operating characteristic curve (ROC curve) as a result of increased specificity values, a slight reduction in sensitivity was observed. The so-called CD8 complex was a unique parameter which improved both the sensitivity (78.79 %) and the specificity (80.77 %) in IMI diagnosis, resulting in the highest area under the ROC curve (0.87). To diagnose subclinical mastitis, the percentage of macrophages and the sum of the percentage PMNLs and T CD8+ cells divided by the percentage of macrophages showed the highest predictive values (sensitivity = 79.63, specificity = 73.68, and area under the ROC curve = 0.83) in the differentiation of the inflammatory condition status of cows. In conclusion, this study provides further insights into using T CD8+ lymphocytes in diagnosing bovine IMIs, combined with PMNLs and macrophages. The antidromic trend of macrophages vs. PMNLs and T CD8+ lymphocytes due to the increasing qSCCs was crucial to differentiating quarters under both inflammatory and non-inflammatory conditions.

Identification of key genes in bovine mammary epithelial cells challenged with Escherichia coli and Staphylococcus aureus by integrated bioinformatics analysis

This study integrated four microarray datasets by Robust Rank Aggregation (RRA) method to identify the differentially expressed genes (DEG) in bovine mammary epithelial (BME) cells in response to Escherichia coli and Staphylococcus aureus infection. Furthermore, the GO function and KEGG pathway enrichment analysis of the integrated DEG were performed. Finally, the protein-protein interaction (PPI) network was constructed. A total of 72 integrated DEG were identified from the four datasets. The most significantly enriched terms within the integrated DEG were mainly involved in the immune response. The PPI network of DEG was constructed with 53 nodes. Seventeen genes, which constitute a significant module, were identified as hub genes. Among them, CD40, CXCL6, and NFKBIZ were further screened as the key genes and have the potential to become biomarkers of E. coli and S. aureus mastitis, considering the specificity of biomarkers for diseases. The identified key genes and pathways in this study can assist in the search for biomarkers for mastitis diagnosis and disease resistance breeding.

Epidemiology of mastitis and interactions of environmental factors on udder health in the compost barn system / Epidemiologia da mastite e interações de fatores ambientais na saúde do úbere no sistema de Compost Barn

This study aimed to describe the epidemiological indexes of mastitis, milk quality and udder hygiene in the Compost Barn system, as well as to search for associations between isolated pathogens from milk with compost characteristics. Three dairy herds participated in the study, and the samples were collected during different periods on each farm. Individual milk samples were collected in duplicate for SCC analysis and microbiological culture. Environmental pathogens caused most cases of clinical mastitis on farm 2, and contagious pathogens caused the most cases on farm 1. Bed moisture was not associated with the incidence of environmental pathogens. Most of the animals remained in good udder hygiene during the study. Poor udder hygiene contributed to the increased incidence of environmental pathogens in one of the farms. A higher number of animals with a hygiene score of ≥ 2 were observed during the warmer and rainfall periods. There was no association between hygiene scores and somatic cell counts. The results suggest that pathogens isolated from milk in animals confined in Compost Barn under tropical climate are like other confinement systems adopted elsewhere. The year period influenced the udder hygiene score, reinforcing the importance of bed management throughout the year.

O objetivo deste estudo foi descrever os índices epidemiológicos da mastite, da qualidade do leite e da higiene do úbere em animais confinados no sistema Compost Barn, bem como buscar associações entre patógenos isolados do leite e características do composto. Três rebanhos leiteiros participaram do estudo e as amostras foram coletadas em diferentes períodos em cada fazenda. Amostras individuais de leite foram coletadas em duplicata para análise de CCS e cultura microbiológica. Patógenos ambientais causaram a maioria dos casos de mastite clínica na fazenda 2, e na fazenda 1 a maioria dos casos foi em decorrência de patógenos contagiosos. Amostras de material da cama foram coletadas em duas fazendas para análise da densidade bacteriana e da umidade. A umidade da cama permaneceu dentro da faixa de controle durante o estudo e não foi associada à incidência de patógenos ambientais. A maioria dos animais permaneceu com boa higiene de úbere durante o estudo. A falta de higiene do úbere contribuiu para o aumento da incidência de patógenos ambientais em uma das fazendas. Durante o período mais quente e mais chuvoso, um número maior de animais com escore de sujidade ≥2 foi observado em todos os rebanhos. Não houve associação entre escore de sujidade e contagem de células somáticas em qualquer uma das três fazendas. Os resultados indicam que o perfil de patógenos isolados do leite em animais confinados em Compost Barn sob clima tropical é semelhante a outros sistemas de confinamento adotados em outros lugares. O período do ano influenciou o escore de higiene do úbere, o que reforça a importância do manejo da cama ao longo do ano.

Commercial mastitis vaccines - effects on mastitis rates and somatic cell counts in Saanen goats

Background: Staphylococcus spp. are the most frequently isolated microorganisms in mastitis cases of small ruminants. The virulence factors of Staphylococcus spp. are critical in the treatment. Therefore, preventive medicine and mastitis control programs, especially herd vaccinations are of great importance in the prevention of mastitis. However, it is not always easy to obtain these vaccines under field conditions. This study, it was aimed to compare the effects of different commercial Staphylococcus spp. vaccines licensed for bovines and species-specific mastitis vaccines on mastitis rates and somatic cell count (SCC) on Saanen goats on field conditions. Materials, Methods & Results: The animal material consisted of 115 (230 udder halves) nulliparous Saanen goats. Goats were randomly grouped as bovine vaccine 1 (BV1 , n = 58), bovine vaccine 2 (BV2 , n = 58), small ruminant vaccine (SRV, n = 56), and control (n = 56). Vaccines were administered to goats in 2 doses according to the label regimen. First milk samples were collected between 0-5 days in milk (DIM) for microbiological analysis and 25-35 DIM for SCC. The other milk samples were collected at 25-35 (1st month) DIM, 60-65 (2nd month) DIM, 85-95 (3rd month) DIM, 115-125 (4th month) DIM, 145-155 (5th month) DIM for microbiological analysis and SCC. Non-aureus staphylococci (NAS) and Staphylococcus aureus were the most frequently isolated microorganism. It was found that the total mastitis rate decreased in vaccine groups compared to the control group. A significant difference was found only in the BV2 and SRV groups. The significant difference in S. aureus infection was found only in the SRV group. Mastitis vaccines used in this study decreased the NAS mastitis rate, but no significant difference was observed. It was found that the clinical mastitis incidence decreased in all vaccine groups compared to the control group, and a significant difference was found between the BV2 and SRV groups compared to the control group (P < 0.05). Somatic cell count was lower in the SRV and BV2 groups compared to the control group (P < 0.05). Discussion: In this study, compatible with the previous reports NAS and S. aureus were the most frequently isolated microorganism. The diversity of virulence factors of Staphylococcus spp. also plays an important role in its high incidence. In some countries, mastitis vaccines used in cows are also administered to small ruminants for reducing infection rates. Similarly, in this study, it was found that the mastitis rate decreased in all vaccine groups compared to the control group. A significant difference was found only in the BV2 and SRV groups. It is thought that the reason for the statistical difference may be due to the biofilm antigen in the BV2 and SRV. In addition, J5 strain in the BV2 is estimated to be effective in reducing the prevalence of gram-negative mastitis. It was observed that the infection rates decreased in the vaccine groups, especially due to S. aureus and NAS. Spontaneous treatment rates were very close to each other between the groups. The reason for the high rate of spontaneous treatment in this study can be explained by the fact that the animals were young and in their 1st lactation. SCC was lower in all vaccine groups compared to the control group. This situation is associated with the decrease in infection rates related to the use of vaccines. It was observed that SCC was lower in the vaccine groups. In addition, SCC was found to be lower in this study compared to similar studies. However, it is evident that the use of species-specific vaccines in the SRV group significantly reduced the rates of total S. aureus mastitis, subclinical NAS mastitis, and new infections by NAS compared to other vaccines. Furthermore, the species-specific vaccine significantly increased the rate of spontaneous treatment for S. aureus mastitis.

Effective treatment of a case of pregnancy toxemia in sheep: case report / Tratamento eficaz de um caso de toxemia de gestação em ovelhas: relato de caso

Pregnancy toxemia has a high mortality rate and few cases with effective treatment are reported, especially when associated with secondary diseases. Therefore, the present work reports the case of a sheep, which was referred to the veterinary hospital of UFMG, in the last month of pregnancy, presenting apathy, hyporexia and sternal recumbency. After the diagnosis of pregnancy toxemia, the fetuses were removed while still alive, but did not survive. Monitoring was started with blood gas analysis, blood glucose assessments and laboratory tests. The results were consistent with liver damage, which was justified by the condition of lipolysis. Treatment consisted of electrolyte replacement plus 50% glucose and potassium chloride, along with administration of antibiotics (ceftiofur, 5mg/kg/SID/IM/7 days), flunixim meglumine (2.2mg/kg/SID/IM first day and 1.1mg/kg/SID/IM on the second and third days) and omeprazole (4mg/kg/SID/oral). The patient had secondarily clinical laminitis, which was treated with cryotherapy and anti-inflammatory drugs, in addition to mastitis, using a single dose of intramammary antibiotics. The work demonstrated the effectiveness of the treatment of pregnancy toxemia, when performed early and intensively, associated with daily clinical and laboratory monitoring of the animal.

A toxemia da prenhez possui alto índice de mortalidade, e poucos casos com tratamento eficaz são relatados, principalmente quando associados a doenças secundárias. Diante disso, o presente trabalho relata o caso de uma ovelha, que foi encaminhada ao hospital veterinário da UFMG, no último mês de gestação, apresentando apatia, hiporexia e decúbito esternal. Após o diagnóstico de toxemia da prenhez, os fetos foram retirados ainda vivos, porém não sobreviveram. Iniciou-se um monitoramento com análises hemogasométricas, avaliações de glicemia e exames laboratoriais. Os resultados foram condizentes com lesão hepática, a qual foi justificada pelo quadro de lipólise. O tratamento consistiu em reposição hidroeletrolítica associada à glicose 50% e a cloreto de potássio, juntamente com administração de antibióticos (ceftiofur, 5mg/kg/SID/IM/7 dias), flunixim meglumine (2,2mg/kg/SID/IM no primeiro dia e 1,1mg/kg/SID/IM no segundo e terceiro dias) e omeprazol (4mg/kg/SID/oral). A paciente apresentou secundariamente laminite clínica, a qual foi tratada com crioterapia e antinflamatórios, além de um quadro de mastite, sendo utilizado antibiótico intramamário em dose única. O trabalho demonstrou a eficácia do tratamento da toxemia da prenhez, quando realizado de forma precoce e intensiva, associado a um monitoramento clínico e laboratorial diário do animal.

Efficacy assessment of an intramammary formulation based on soluble polypyrrole in cows with experimentally induced mastitis / Avaliação da eficácia de uma formulação intramamária à base de polipirrol solúvel em vacas com mastite experimentalmente induzida

Considerando a necessidade de terapias alternativas para a mastite bovina, uma inflamação, normalmente de causa infecciosa, de alta prevalência e de alto impacto econômico nas fazendas leiteiras, avaliou-se a eficácia antimicrobiana, in vivo, de uma formulação intramamária à base de polipirrol (PPy) solúvel, um polímero condutor promissor para aplicações biomédicas, especialmente como potente antibacteriano. Neste ensaio, quartos mamários de vacas holandesas sadias (n = 8) foram inoculados com Staphylococcus aureus e tratados, por via intramamária, com formulação experimental à base de PPy solúvel (5%) e com formulação comercial à base de sulfato de gentamicina. O efeito desses tratamentos foi avaliado com a realização de lactoculturas, da Contagem Bacteriana Total (TBC), da Contagem de Células Somáticas (SCC) e da análise da composição do leite das amostras obtidas de quartos mamários, em sete momentos experimentais. Avaliação hematológica dos animais também foi realizada. A aplicação intramamária de três doses da formulação experimental à base de PPy solúvel resultou em maiores log/mL da TBC e da SCC quando comparadas ao grupo controle positivo e ao grupo que recebeu sulfato de gentamicina. A administração da formulação experimental não induziu alterações na composição do leite e nos parâmetros hematológicos. Alguns fatores farmacocinéticos e farmacodinâmicos do PPy solúvel podem ser atribuídos a ineficácia antimicrobiana da pomada experimental. Outras pesquisas devem ser realizados em prol do desenvolvimento de formulações que permitam a atuação antibacteriana do PPy solúvel no ambiente intramamário de vacas leiteiras.

Given the need for alternative therapies for bovine mastitis, an infectious disease of high prevalence and significant economic impact in dairy farms, this study evaluated the in vivo antimicrobial efficacy of an intramammary formulation based on soluble polypyrrole (PPy), a promising conductive polymer for biomedical applications, especially as an effective antimicrobial agent. In this assay, mammary quarters of healthy Holstein Friesian cows (n = 8) were inoculated with Staphylococcus aureus and treated, via the intramammary route, with an experimental formulation based on soluble PPy (5%) and a commercial formulation based on gentamicin sulfate. The effect of these treatments was evaluated based on milk cultures, Total Bacterial Count (TBC), Somatic Cell Count (SCC), and milk composition analysis of mammary quarter samples in seven experimental moments. In addition, hematological evaluations of the animals were also performed. The intramammary application of three levels of the experimental formulation based on soluble PPy resulted in higher log/mL of the TBC and SCC compared to a positive control group and a group that received gentamicin sulfate. The experimental formulation did not induce changes in milk composition or in hematological parameters. Certain factors related to pharmacokinetics, such as the type of carrier used in the formulation and the pharmacodynamics of soluble PPy, may have contributed to the antimicrobial ineffectiveness of the experimental formulation. The results of this study neither define nor decrease the antimicrobial potential of soluble PPy. Further research is required to develop formulations that enable the antibacterial action of soluble PPy in the intramammary environment of dairy cows.

Prevalence and influence of clinical and subclinical mastitis in the service period of dairy cows in Tarumirim (MG) / Prevalência e influência da mastite clínica e subclínica no período de serviço de vacas leiteiras em Tarumirim (MG)

The objective was to assess the prevalence and influence of clinical and subclinical mastitis during the service period of cows in a herd in Tarumirim (MG), from October 2019 to May 2020. Around 65 Gir x Holstein and Guzerá x Holstein lactating crossbred cows were evaluated. Subclinical mastitis was diagnosed by means of the California Mastitis Test (CMT), and clinical mastitis, by means of the strip cup test and the animals' clinical signs. Pregnancy after calving was diagnosed by the rectal palpation method, with the aid of ultrasound. The time from calving to conception was considered as the service time. The prevalence rates of clinical and subclinical mastitis were 2.9 and 63.7%, respectively, throughout the experimental period. The mean service period was shorter (p<0.05) in healthy cows (63.1 days) than in cows with subclinical mastitis (88.5 days) and clinical mastitis (111.2 days). The service period increased by 30.9 days for each mammary quarter with clinical mastitis (p<0.05). With each increase in the degree and days of duration of clinical and subclinical mastitis, the service period rose by 25.4 and 6.5 days, and 8.5 and 0.6 days, respectively (p<0.05). Therefore, mastitis increases the service period of dairy cows. Good milking hygiene and animal handling practices should be adopted in order to reduce the prevalence of mastitis in the herd.(AU)

Objetivou-se avaliar a prevalência e influência da mastite clínica e subclínica no período de serviço de vacas em um rebanho de Tarumirim (MG), ao longo de outubro de 2019 a maio de 2020. Em torno de 65 vacas mestiças Gir x Holandês e Guzerá x Holandês em lactação foram avaliadas. A mastite subclínica foi diagnosticada por meio de California Mastitis Test(CMT) e a mastite clínica por meio do teste da caneca e sinais clínicos dos animais. O diagnóstico de gestação após o parto foi realizado pelo método de palpação retal, com auxílio de ultrassom. O tempo do parto até a concepção foi considerado como o tempo de serviço. As prevalências de mastite clínica e subclínica foram de 2,9 e 63,7%, respectivamente, ao longo do período experimental. O período de serviço médio foi menor (p<0,05) em vacas sadias (63,1 dias) que em vacas com mastite subclínica (88,5 dias) e clínica (111,2 dias). O período de serviço aumentou 30,9 dias a cada quarto mamário com mastite clínica (p<0,05). A cada aumento do grau e dias de duração da mastite clínica e subclínica, o período de serviço aumentou 25,4 e 6,5 dias e 8,5 e 0,6 dias, respectivamente (p<0,05). Portanto, a mastite aumenta o período de serviço de vacas leiteiras. Boas práticas de higiene de ordenha e manejo dos animais devem ser adotadas para reduzir a prevalência de mastite no rebanho.(AU)

Training, development, and evaluation of on-farm culturing as a technical resource to reduce the use of antimicrobials in dairy herds in the Midwest Region of Santa Catarina State, Brazil / Capacitação, implementação e avaliação da cultura de leite na fazenda como recurso técnico voltado ao uso reduzido de antimicrobianos em rebanhos leiteiros no meio oeste catarinense

On-farm culturing is a technology booming in Brazil. It is based on the microbiological diagnosis of milk samples collected from clinical cases of bovine mastitis, on the farm where the animals are handled, quickly, simply, and at an affordable cost. With this resource, after 24 h of incubation, the isolated microorganisms are classified as gram positive or gram negative, helping to make decisions regarding the therapy of the animals. Considering the relevance of the Midwestern region of Santa Catarina State in the national dairy production scenario, the objectives of the study were: 1) to promote the technical training of the farmers in three dairy farms located in Treze Tílias-SC, 2) to assist in the implementation and evaluation of on-farm culturing as technological resource viewing the reduced use of antimicrobials in herds. In addition to the rapid acceptance by the farmers and their efficient training, with the use of the technology, there was a 45-50% reduction in the use of antimicrobials in dairy herds. This result demonstrated a significant effect on animal health, and determines an important cost reduction for farmers, as presented in detail in this manuscript.

A cultura de leite na fazenda (do inglês On farm culturing) é uma tecnologia em franca expansão no Brasil. Fundamenta-se no diagnóstico microbiológico de amostras de leite colhidas de casos clínicos de mastite bovina, na própria fazenda onde são manejados os animais, de forma rápida, simples e com custo acessível. Com este recurso, após 24 horas de incubação, os micro-organismos isolados são classificados em Gram-positivos ou Gram-negativos, auxiliando na tomada de decisões quanto à terapia dos animais. Considerando a relevância da região meio oeste catarinense no cenário nacional de produção leiteira, o objetivo do presente estudo foi promover a capacitação técnica dos produtores em três propriedades localizadas em Treze Tílias-SC, e auxiliar na implementação e avaliação da cultura de leite na fazenda como recurso tecnológico voltado ao uso reduzido de antimicrobianos nos rebanhos. Além da rápida aceitação pelos produtores e eficiente capacitação dos mesmos, verificou-se, com o emprego da tecnologia, redução de 45% a 50% do uso de antimicrobianos nos rebanhos. Este resultado, além de demonstrar significativo impacto em saúde animal, determinou importante redução de custos aos produtores, como apresentado detalhadamente no presente artigo.

Training, development, and evaluation of on-farm culturing as a technical resource to reduce the use of antimicrobials in dairy herds in the Midwest Region of Santa Catarina State, Brazil / Capacitação, implementação e avaliação da cultura de leite na fazenda como recurso técnico voltado ao uso reduzido de antimicrobianos em rebanhos leiteiros no meio oeste catarinense

ABSTRACT: On-farm culturing is a technology booming in Brazil. It is based on the microbiological diagnosis of milk samples collected from clinical cases of bovine mastitis, on the farm where the animals are handled, quickly, simply, and at an affordable cost. With this resource, after 24 h of incubation, the isolated microorganisms are classified as gram positive or gram negative, helping to make decisions regarding the therapy of the animals. Considering the relevance of the Midwestern region of Santa Catarina State in the national dairy production scenario, the objectives of the study were: 1) to promote the technical training of the farmers in three dairy farms located in Treze Tílias-SC, 2) to assist in the implementation and evaluation of on-farm culturing as technological resource viewing the reduced use of antimicrobials in herds. In addition to the rapid acceptance by the farmers and their efficient training, with the use of the technology, there was a 45-50% reduction in the use of antimicrobials in dairy herds. This result demonstrated a significant effect on animal health, and determines an important cost reduction for farmers, as presented in detail in this manuscript.

RESUMO: A cultura de leite na fazenda (do inglês On farm culturing) é uma tecnologia em franca expansão no Brasil. Fundamenta-se no diagnóstico microbiológico de amostras de leite colhidas de casos clínicos de mastite bovina, na própria fazenda onde são manejados os animais, de forma rápida, simples e com custo acessível. Com este recurso, após 24 horas de incubação, os micro-organismos isolados são classificados em Gram-positivos ou Gram-negativos, auxiliando na tomada de decisões quanto à terapia dos animais. Considerando a relevância da região meio oeste catarinense no cenário nacional de produção leiteira, o objetivo do presente estudo foi promover a capacitação técnica dos produtores em três propriedades localizadas em Treze Tílias-SC, e auxiliar na implementação e avaliação da cultura de leite na fazenda como recurso tecnológico voltado ao uso reduzido de antimicrobianos nos rebanhos. Além da rápida aceitação pelos produtores e eficiente capacitação dos mesmos, verificou-se, com o emprego da tecnologia, redução de 45% a 50% do uso de antimicrobianos nos rebanhos. Este resultado, além de demonstrar significativo impacto em saúde animal, determinou importante redução de custos aos produtores, como apresentado detalhadamente no presente artigo.

Economic and production aspects ofmilking management in dairy farming / Aspectos econômicos e produtivos do manejo de ordenha na pecuária leiteira

The Brazilian dairy sector is important for the world agricultural production; however, it presents problems in production efficiency and milk quality, since the occurrence of mastitis in the herds can reach 47%. The present study analyzed data from a rural property with 100 lactating cows in a semi-intensive breeding system, which did not adopt adequate hygiene management for milking processes. Corrective measures were proposed, such as daily strip cup test, biweekly California Mastitis Test, formation of a new milking line, and daily pre dipping and post dipping and cleaning of teat cups. Milk samples from 10 animals with positive clinical mastitis, 10 animals with positive subclinical mastitis, and from the cooling tank were collected at one day before and 90 days after the implementation of the proposed measures and sent to a laboratory for analysis of somatic cell counting (SCC) and total bacteria counting (TBC). An increase of 17% in milk production and decreases of 64% and 40% in clinical and subclinical mastitis, respectively, were found after 90 days, with a consequent decrease in SCC and TBC. The milking duration after this period denoted an adaptation of the employees to the new procedures. The production financial yield was calculated based on the implementation costs of the adopted adequations and increases in milk production, representing a profitability increase of 10.4%. The implemented adequations were efficient for the control of mastitis and increase in milk yield and quality, resulting in a positive economic return.(AU)

O setor lácteo brasileiro possui grande relevância na produção agrícola mundial e apesar disso, ainda são encontra-dos problemas na eficiência produtiva e na qualidade do leite, onde a prevalência de mastite nos rebanhos pode chegar a 47%. Neste estudo, foram analisados dados de uma propriedade rural com 100 vacas lactantes e sistema de criação semi-intensivo, que não adotava manejo higiênico adequado na ordenha. Foram propostas medidas de correção como execução diária do teste da caneca telada e teste quinzenal do CMT, formação de nova linha de ordenha, adoção diária do pré dipping e pós dipping e higienização das teteiras. Foram coletadas amostras de leite de 10 animais positivos para mastite clínica, 10positivos para mastite subclínica e do tanque de resfriamento um dia antes e 90 dias após a implementação das novas medidas e enviadas ao laboratório para análise da CCS e CBT. Após 90 dias, houve aumento na produção de leite em 17% e redução dos índices de mastite clínica e subclínica em 64% e 40%, respectivamente, com consequente diminuição dos valores de CCS e CBT. A duração da ordenha após esse período indicou adaptação dos colaboradores aos novos procedimentos instaurados. Por fim, calculou-se o rendimento financeiro da produção baseado nos custos de implantação das correções e no aumento da produção de leite, que reverteu-se em lucratividade 10,4% maior. Conclui-se que as adequações implementadas foram eficazes no con-trole de mastite e no aumento da produtividade dos animais e da qualidade do leite, resultando em retorno econômico positivo.(AU)

Training, development, and evaluation of on-farm culturing as a technical resource to reduce the use of antimicrobials in dairy herds in the Midwest Region of Santa Catarina State, Brazil / Capacitação, implementação e avaliação da cultura de leite na fazenda como recurso técnico voltado ao uso reduzido de antimicrobianos em rebanhos leiteiros no meio oeste catarinense

On-farm culturing is a technology booming in Brazil. It is based on the microbiological diagnosis of milk samples collected from clinical cases of bovine mastitis, on the farm where the animals are handled, quickly, simply, and at an affordable cost. With this resource, after 24 h of incubation, the isolated microorganisms are classified as gram positive or gram negative, helping to make decisions regarding the therapy of the animals. Considering the relevance of the Midwestern region of Santa Catarina State in the national dairy production scenario, the objectives of the study were: 1) to promote the technical training of the farmers in three dairy farms located in Treze Tílias-SC, 2) to assist in the implementation and evaluation of on-farm culturing as technological resource viewing the reduced use of antimicrobials in herds. In addition to the rapid acceptance by the farmers and their efficient training, with the use of the technology, there was a 45-50% reduction in the use of antimicrobials in dairy herds. This result demonstrated a significant effect on animal health, and determines an important cost reduction for farmers, as presented in detail in this manuscript.(AU)

A cultura de leite na fazenda (do inglês On farm culturing) é uma tecnologia em franca expansão no Brasil. Fundamenta-se no diagnóstico microbiológico de amostras de leite colhidas de casos clínicos de mastite bovina, na própria fazenda onde são manejados os animais, de forma rápida, simples e com custo acessível. Com este recurso, após 24 horas de incubação, os micro-organismos isolados são classificados em Gram-positivos ou Gram-negativos, auxiliando na tomada de decisões quanto à terapia dos animais. Considerando a relevância da região meio oeste catarinense no cenário nacional de produção leiteira, o objetivo do presente estudo foi promover a capacitação técnica dos produtores em três propriedades localizadas em Treze Tílias-SC, e auxiliar na implementação e avaliação da cultura de leite na fazenda como recurso tecnológico voltado ao uso reduzido de antimicrobianos nos rebanhos. Além da rápida aceitação pelos produtores e eficiente capacitação dos mesmos, verificou-se, com o emprego da tecnologia, redução de 45% a 50% do uso de antimicrobianos nos rebanhos. Este resultado, além de demonstrar significativo impacto em saúde animal, determinou importante redução de custos aos produtores, como apresentado detalhadamente no presente artigo.(AU)

Isolation of Escherichia coli and Staphylococcus aureusin raw milk from refrigeration tanks: identification and antimicrobial resistance profiles / Isolamento de Escherichia coli e Staphylococcus aureus em leite cru de tanques de refrigeração: identificação e perfis de resistência antimicrobiana

Escherichia coli and Staphylococcus aureus in milk cooling tank reflects a hygienic deficit in animal management, production environment, and milk obtainment. With implications for public health as agents of infection and food poisoning, and the presence of antimicrobial-resistant strains. Therefore, were investigated in cooling tanks with high counts of somatic cells and total bacteria in milk. Microorganisms, in which a profile of resistance to antimicrobials was investigated, and whether there was a similarity in this profile between the strains of the eight dairy properties.Therefore, eighty-eight samples were obtained, and inoculated on Compact Dry® plates. Of this total, 27.27% (24/88) samples tested positive for E. coli and 56.81% (50/88) for S. aureus. Among 24 E. coli strains subjected to disk-diffusion antibiograms, 70.83% were resistant to rifampicin, 50% to ampicillin and 41.67% to cefoxitin and erythromycin, while of the 51 S. aureus strains, 94.32% expressed resistance to azetroanam, 86.27% to ampicillin and nalidixic acid, 76.47% to rifampicin and 47.06 % to erythromycin and cefoxitin. A criterion of resistance to over three antibiotics was observed for 8.33% (2/24) of the isolated E. coli strains and 17.65% (9/51) of the S. aureus strains, characterizing them as multidrug resistant (MDR) strains. Resistance phenotypes displayed high similarity between properties F5 and F6 for S. aureus, and properties F6 and F8 for E. coli when applying the Jaccard index. The presence of these antibiotic-resistant pathogenic microorganisms indicate flaws in milk production handling and sanitary conditions, representing risk to milk consumers.(AU)

Escherichia coli e Staphylococcus aureus no tanque de resfriamento de leite refletem um déficit higiênico no manejo animal, ambiente de produção e obtenção de leite. Com implicações para a saúde pública como agentes de infecção e intoxica-ção alimentar e presença de cepas resistentes a antimicrobianos. Portanto, foram investigados em tanques de resfriamento com altas contagens de células somáticas e bactérias totais no leite. Microrganismos, nos quais foi investigado o perfil de resistência aos antimicrobianos e se havia semelhança nesse perfil entre as cepas das oito propriedades leiteira. Para tanto, oitenta e oito amostras foram coletadas inoculadas em placas de Compact Dry®, destas 27,27% (24/88) amostras revelaram contaminação com E. coli, e 56,81% (50/88) com S. aureus. Entre 24 cepas de E. coli submetidas a antibiograma por disco-difusão 70,83% foram resistentes a rifampicina, 50% ampicilina, 41,67% cefoxitina e eritromicina, enquanto das 51 cepas de S. aureus 94,32% expressaram resistência a azetroanam, 86,27% a ampicilina e nalidíxico ácido, 76,47 % a rifampicina, e 47,06% a cefoxitina e eritromicina. O critério de resistência a mais de três antibióticos caracterizou 8,33% (2/24) das cepas de E. coli, e 17,65% (9/51) de S. aureus como multidroga resistente (MDR). O fenótipo resistência mostrou elevada similaridade entre as proprie-dades (F5 e F6) para S. aureus, e das propriedades (F6 e F8) para E. coli aplicando-se o índice de Jaccard. Estes microrganis-mos patogênicos resistentes a antibióticos, indicam falhas no manuseio e obtenção higiênica do leite, e que estes representam risco aos consumidores do leite.(AU)

Biofilm production by Staphylococcus spp. isolated from bovine mastitis in dairy herds in state of Acre, Brazil and its implications / Produção de biofilme por Staphylococcus spp. isolados de mastite bovina, em rebanhos leiteiros do estado do Acre, Brasil, e suas implicações

This study aimed to identify the Staphylococcus species responsible for bovine mastitis in dairy herds in northern Brazil, to investigate the capacity of biofilm production, and to analyze the association of biofilm production with multiresistance and intensity of California Mastitis Tests (CMT) reactions that can make treatment more difficult and cause misdiagnoses, respectively. Milk samples were collected from 23 dairy farms located in five municipalities in the state of Acre. A total of 339 crossbred cows were tested by CMT, with 109 animals (229 udder ceilings) reacting to the test. After bacterial isolation in blood agar, the catalase-positive and gram-positive cocci were submitted for identification by MALDI-TOF MS. Of 103 strains identified as staphylococci, Staphylococcus chromogenes (58.3%) and Staphylococcus aureus (19.4%) were the most prevalent species. Biofilm production was quantitatively evaluated using a microplate adherence test. Among the Staphylococcus strains, 71.8% were biofilm producers. Most strains of S. chromogenes (68.3%) had the capacity to produce biofilms, ranging from weak (43.3%), moderate (13.3%), and strong (11.7%) producers. Among S. aureus strains, 50% were non-biofilm producers, and none were strong producers. Our data showed an association between biofilm production capacity and multidrug resistance. In addition, there was a reduction in the response to the CMT test, which can mask the diagnosis.

O presente estudo teve como objetivos identificar as espécies de estafilococos envolvidas com mastite em rebanhos leiteiros no norte do Brasil, investigar a capacidade de produção de biofilme e analisar a associação da produção de biofilme com multirresistência e intensidade de reações de CMT que podem dificultar o tratamento e causar erros de diagnósticos, respectivamente. Amostras de leite foram coletadas em 23 propriedades leiteiras, situadas em cinco municípios do estado do Acre. Um total de 339 vacas mestiças foram testadas pelo CMT, sendo detectados 109 animais (229 tetos) reagentes ao teste. Após isolamento em ágar sangue, os cocos Gram positivos produtores de catalase foram submetidos à identificação por MALDI TOF MS. Um total de 103 estirpes foram identificadas como estafilococos, sendo mais prevalentes as espécies Staphylococcus chromogenes (58,3%) e S. aureus (19,4%). A produção de biofilme foi avaliada quantitativamente pelo teste de aderência em microplaca. Dentre todas as amostras de estafilococos, 71,8% foram produtoras de biofilme. A maioria das amostras de S. chromogenes (68,3%) apresentou capacidade de produzir biofilme, variando de fraco (43,3%), moderado (13,3%) a forte (11,7%) produtor. Entre as amostras de S. aureus, 50% não foram produtoras e nenhuma foi produtora forte. Essa capacidade de produção de biofilme mostrou-se associada à multirresistência a antimicrobianos, além de diminuir a intensidade no teste CMT, podendo mascarar o diagnóstico.

Ceftiofur efficacy in the intramammary extended treatment of staphylococcal subclinical mastitis in primiparous cows / Eficácia do ceftiofur no tratamento estendido intramamário da mastite subclínica por estafilococos em vacas primíparas

Extended therapy is an alternative approach to treat nonresponsive staphylococcal mastitis, although it has been used mainly in adult cows. This study investigated the efficacy of intramammary ceftiofur in the treatment of staphylococcal subclinical mastitis in primiparous cows. Sixty primiparous cows Holstein were divided into four groups (G1 = Group negative to staphylococci infection, G2 = Group positive to staphylococci infection untreated with intramammary ceftiofur, Group, G3 = Group treated with intramammary ceftiofur early lactation, G4 = Group treated with intramammary ceftiofur late lactation group) with milk samples collected at five moments (M0 = diagnosis of subclinical mastitis, M1 = 7 days after diagnosis of subclinical mastitis and early extended therapy, M2 = 14 after the diagnosis of subclinical mastitis, M3 = 21 days after diagnosis of mastitis) and M4 = 28 days after diagnosis of mastitis). In groups G3 and G4, which were treated with intramammary ceftiofur, the microbiological cure was evidenced by a reduction in SCC of 73.3% and 46.7%, respectively. Thus, in the treated groups (G3 + G4) and untreated (G2), cure rates were 60% and 26.7%, respectively (P <0.05). Forty-five strains of staphylococci were Motta, R. G. et al.1958Semina: Ciênc. Agrár. Londrina, v. 43, n. 5, p. 1957-1974, set./out. 2022isolated, with a predominance of S. aureus (51,1%) and S. intermedius (48,8%). The in vitro antimicrobial susceptibility pattern showed higher sensitivity indices of isolates for oxacillin (80%), ceftiofur (77.8%), cephalexin (77.8%), ciprofloxacin (66.7%), and gentamicin (60%). In contrast, cloxacillin (24.4%), penicillin (35.6%), and tetracycline (44.5%) were ineffective antimicrobials for staphylococci isolates. Among the milk samples taken when M0 and M1 (7 days after isolation), 13.3% were positive for the detection of the inhibiting substances (antimicrobials) in Delvotest™ and all negative in the Snap test™, whereas in the M2 (14 days after isolation), 55% were positive in Delvotest™ and 46.7% in the Snap test™. Twenty-one days after diagnosis (M3), 16.7% revealed positive results in Delvotest™ and 11.7% in the Snap test™. For M4 (28 days after isolation), 11.7% showed positive results in Delvotest™, and 8.3% revealed positive results in the Snap test™. There was a reduction in SCC among all cured animals. Significant results were identified for milk production in the M0, so G1 produced more milk than the other three groups, G2, G3, and G4. A statistical association was observed between the reduction in the volume of daily milk and production in animals with subclinical mastitis, denoting losses in milk production in primiparous bovines infected during lactation by staphylococci. Extended intramammary therapy with ceftiofur in bovine primiparous cows subclinically affected by staphylococcal mastitis is effective mainly in cases treated at the beginning of lactation, showing microbiological cure and reduction in SCC.(AU)

O estudo presente investigou a eficácia do ceftiofur intramamário no tratamento da mastite subclínica por estafilococos em primíparas bovinas. Foram utilizados 60 animais da raça holandesa, divididos em quadro grupos (G1 = Grupo negativo, G2 = Grupo positivo não tratado com ceftiofur intramamário, G3 = Grupo tratado com ceftiofur intramamário no início da lactação, G4 = Grupo tratado com ceftiofur intramamário no final da lactação), com amostras de leite coletadas em cinco momentos (M0 = diagnóstico da mastite subclínica, M1 = 7 dias após diagnóstico e início da terapia estendida, M2 = dia 14 após o diagnóstico da mastite subclínica, M3 = dia 21 após o diagnóstico da mastite, M4 = dia 28 após o diagnóstico da mastite). Nos grupos tratados com ceftiofur intramamário, foi evidenciada a cura microbiológica com redução na CCS em 73,3% no G3 e 46,7% no G4. Nos grupos tratados (G3+G4) e não tratado (G2), as taxas de cura foram, respectivamente, 60% e 26,7% (p<0,05). Foram isoladas 45 linhagens de estafilococos, com predomínio de S. aureus (51,1%) e S. intermedius (48,8%). O perfil de sensibilidade microbiana "in vitro" dos isolados apresentou maiores índices de sensibilidade para oxacilina (80%), ceftiofur (77,8%) e cefalexina (77,8%), ciprofloxacino (66,7%) e gentamicina (60%). Em contraste, cloxacilina (24,4%), penicilina (35,6%) e tetraciclina (44,5%) foram os antimicrobianos menos efetivos diante dos estafilococos isolados. Nas amostras de leite colhidas nos momentos M0 e M1, 13,3% foram positivas para o teste de detecção de substâncias inibidoras na prova de Delvotest™ e todas negativas no Snap test™. Já, no M2, 55% foram positivas no Delvotest™ e 46,7% no Snap test™. No M3, 16,7% positivas no Delvotest™ e no 11,7% no Snap test™. No M4, 11,7% positivas no Delvotest™ e 8,3% no Snaptest™, dois dias após o término do tratamento (M2). Foram identificados nos grupos G3 e G4 a presença de animais positivos em 96,7% para o Delvotest™ e 90% para o Snap test™. Ocorreu redução na CCS em todos os animais curados. Foram identificados resultados significativos para a produção de leite no MO, posto que o G1 produziu mais leite se comparado aos outros três grupos G2, G3 e G4. Foi observada associação estatística entre a redução no volume de leite diário e a produção nos animais com mastite subclínica, denotando prejuízos na produção de leite em primíparas bovinas infectadas na lactação por estafilococos. A terapia intramamária estendida com ceftiofur em primíparas com mastite estafilocócica é eficaz principalmente nos casos tratados no início da lactação, mostrando cura microbiológica e redução da CCS, indicando que esta abordagem terapêutica alternativa pode ser utilizada para o tratamento de novilhas.(AU)

Interference of natural extract from Jatobá (Hymenaea martiana Hayne) with the physico-chemical characteristics and yield of goat milk and cheese / [Interferência do extrato natural de jatobá (Hymenaea martiana Hayne) sobre as características físico-químicas e o rendimento do leite e queijo coalho de cabra]

Several studies have assessed the therapeutic potential of natural products against mastitis, but only a few have evaluated the impacts of this alternative therapy on the main properties of milk and dairy products. In this study, we observed how the treatment of mastitis with ethanolic extract of Jatobá (Hymenaea martiana Hayne) influenced the physicochemical and sensory characteristics of coalho cheese. An ointment containing the ethanolic extract was prepared for intramammary use in six dairy goats. The experiment was conducted in three experimental moments. Milking was performed, manually, and both milk and cheese were subjected to physicochemical and sensory tests. No difference was observed (p>0.05) in the physicochemical aspects of milk between the studied groups. The solids-non-fat showed a statistical difference between experimental moments M1 and M2. The protein means varied from 3.33 to 3.62, and there was a statistical difference between the two moments, while the lactose means varied from 4.79 to 5.38%. The physicochemical aspects of cheese remained similar with both treatments. Except for appearance, the sensory characteristics showed no statistical difference. In conclusion, the use of Jatobá extract ointment did not influence the physicochemical and sensory characteristics of goat milk or cheese.

A mastite representa uma das principais enfermidades nos rebanhos de caprinos leiteiros, com implicações na produção de leite e na qualidade final dos derivados. Objetivou-se observar a influência do tratamento da mastite com o extrato etanólico da Hymenaea martiana Hayne sobre as características físico-químicas e sensoriais do queijo tipo coalho. Uma pomada contendo extrato foi elaborada para uso intramamário em seis fêmeas caprinas especializadas na produção de leite. As metades esquerdas dos tetos das cabras receberam essa infusão, enquanto a metade direita era controle. O experimento foi conduzido em três momentos experimentais. Realizou-se ordenha manual e análise físico-química do leite. Para o queijo, foram realizados testes físico-químicos e teste sensorial. Quantos aos aspectos físico-químicos do leite, é possível afirmar que não houve diferença (P>0,05) entre os grupos. Houve diferença estatística para sólidos não gordurosos nos momentos experimentais M1 e M2. As médias de proteína variaram entre 3,33 e 3,62, e houve diferença estatística em dois momentos. As médias de lactose variaram entre 4,79% e 5,38%. Os aspectos físico-químicos do queijo mantiveram resultados similares entre os dois tratamentos. Os parâmetros sensoriais para o queijo coalho de cabra não tiveram diferença estatística entre os tratamentos, contudo a aparência se destacou em relação aos demais parâmetros sensoriais. O uso da pomada elaborada com extrato de jatobá não interferiu sobre as características físico-químicas do leite de cabra e sobre as características físico-químicas e sensoriais do queijo tipo coalho de cabra.

Effect of somatic cell count on milk composition and some chemical properties of milk / Investigação do efeito da contagem de células somáticas na composição e algumas propriedades químicas do leite

Subclinical mastitis is a very important disease for dairy cattle farms. As a result of the deterioration of milk quality, it causes economic losses in enterprises. Milk samples of 180 cows were divided into five groups according to the somatic cell count. Some chemical properties and composition were measured in milk samples. The ratio of solid-non-fat, mineral matter, lactose, and protein decreased as the somatic cell count of the milk increased (P<0.05). No statistical difference was observed between the fat content of milk and the level of somatic cell count (P>0.05). Although specific gravity decreases (P<0.05), the electrical conductivity increases (P<0.001) in milk with high levels of somatic cell count. The milk quality of dairy cattle deteriorates due to the high somatic cell count. Therefore, regular monitoring of somatic cell count is recommended in dairy farms to monitor changes in fat, protein, solid-non-fat, lactose, and mineral matter ratios as well as some chemical properties that make up the milk composition.

A mastite subclínica é uma doença muito importante para as fazendas de gado leiteiro. Como resultado da deterioração da qualidade do leite, ela causa perdas econômicas nas empresas. Amostras de leite de 180 vacas foram divididas em cinco grupos de acordo com o nível de contagem de células somáticas (SCC). Algumas propriedades químicas e composição foram medidas em amostras de leite. A proporção de sólido sem gordura, matéria mineral, lactose e proteína diminuiu à medida que a SCC do leite aumentava (P<0,05). Nenhuma diferença estatística foi observada entre o conteúdo de gordura do leite e o nível de contagem de células somáticas (P>0,05). Embora a gravidade específica diminua (P<0,05), a condutividade elétrica aumenta (P<0,001) no leite com altos níveis de contagem de células somáticas. A qualidade do leite do gado leiteiro se deteriora devido à alta contagem de células somáticas. Portanto, o monitoramento regular da SCC é recomendado nas fazendas de leite para monitorar mudanças nas proporções de gordura, proteína, sólidos não gordurosos, lactose e matéria mineral, bem como algumas propriedades químicas que compõem a composição do leite.

Effect of Mauritia flexuosa L. leaf extract on Staphylococcus aureus and Staphylococcus haemolyticus biofilms adhered to stainless steel surface / Efeito do extrato de folhas de Mauritia flexuosa L. sobre biofilmes de Staphylococcus aureus e Staphylococcus haemolyticus aderidos a superfície de aço inoxidável

Staphylococcus spp. represents the main mastitis agents in ruminants and contaminants of milk due to their expressive capacity to make biofilms. The aims in this study was evaluate evaluated the antimicrobial activity of Mauritia flexuosa L. extracts against Staphylococcus spp. adhered to a stainless steel surface. Two isolates from cows with clinical mastitis were evaluated; one was identified as Staphylococcus aureus, and the other Staphylococcus haemolyticus. Additionally the ATCC 25923 strain, S. aureus from human was evaluated. The chemical profile obtained from gas chromatography revealed the presence of carbohydrates, organic acids, and flavonoids. The minimum bactericidal concentrations of the ethanolic extract (EE) and aqueous extract (AE) were 4.4 and 5.82 mg/mL, respectively. After EE treatment at 4.4 mg/mL for 2.5 min, total removal of mature biofilms grown on stainless steel coupons was observed (reduction by 3.85-4.81 log units). This extract from M. flexuosa shows potential as an effective sanitizer and may represent a natural alternative against Staphylococcus spp.

Bactérias do gênero Staphylococcus spp. são os principais agentes da mastite em ruminantes e contaminantes do leite devido à expressiva capacidade de formação de biofilmes. Neste estudo o objetivo foi avaliar a atividade antimicrobiana de extratos de Mauritia flexuosa L. (Buritizeiro) contra Staphylococcus spp. aderidos à superfície de aço inoxidável. Foram avaliados dois isolados de vacas com mastite clínica; o um isolado foi identificado como Staphylococcus aureus e o outro como Staphylococcus haemolyticus. Adicionalmente foi também avaliada a e a cepa S. aureus ATCC 25923 de origem humana. O perfil químico obtido por cromatografia gasosa revelou a presença de carboidratos, ácidos orgânicos e flavonóides. As concentrações bactericidas mínimas do extrato etanólico (EE) e do extrato aquoso (AE) foram 4,4 e 5,82 mg / mL, respectivamente. Após o tratamento com EE a 4,4 mg / mL por 2,5 min, foi observada remoção total de biofilmes maduros cultivados em cupons de aço inoxidável (redução de 3,85-4,81 unidades log). O EE de folhas de M. flexuosa apresenta potencial como um desinfetante eficaz e pode representar uma alternativa natural contra Staphylococcus spp.

Species identification and antimicrobial susceptibility profile of bacteria associated with cow mastitis in southern Brazil / Identificação de espécies e perfil de suscetibilidade aos antimicrobianos de bactérias associadas à mastite bovina no sul do Brasil

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.

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.