RESUMO

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.

Assuntos

RESUMO

This research communication paper addresses the hypothesis that the use of therapeutic alternatives for mastitis, such as intramammary ozone, can cure the disease with lower costs and without harmful residues for human consumption and without formation of microbial resistance like the ones caused by indiscriminate use of antibiotics in dairy farms. The study was performed in 36 mammary quarters from 12 dairy cows with subclinical mastitis grade three. The experimental units were randomly assigned into four groups and each group received a treatment. Treatments comprised (a) 20 µg/ml ozone gas; (b) 40 µg/ml ozone gas; (c) negative control treatment of 12.5 µg/ml ozonated saline and (d) positive control treatment of 100 mg of cephalexin + 100 mg of neomycin + 10 mg of prednisolone, all by intramammary injection. In all quarters, milk was collected before and after the application of treatments for California mastitis test and evaluation of milk composition, somatic cell count, and bacterial cultures. The results indicated that the use of intramammary ozone did have a therapeutic effect, and whilst this was less than that of antibiotics, ozone does confer some advantages. Treated milk had a good composition, the treatment cost was low, milk withdrawal may not be necessary and there is no risk of antibiotic resistance.

Assuntos

RESUMO

BACKGROUND: Mastitis is one of the major diseases in dairy cattle, as it causes great economic losses to producers due to the reduction of milk production and changes in the quality of the product. The disease is mainly caused by bacteria of the genus Staphylococcus spp., these microorganisms can express various virulence factors, such as biofilms for example. In herds with organic management, producers and technicians use unconventional ways to treat and control the disease, such as homeopathy. However, it is not known if this type of treatment is able to control pathogenic bacteria such as those of the genus Staphylococcus, of relevance to animal and human health. Thus, the objective of this study was to investigate the production of biofilm in vitro and its genes by Staphylococcus spp. isolated in the milk of cows treated with homeopathy, as well as the persistence of microorganisms in animals. METHODS: Ninety-nine isolates of Staphylococcus spp. from cows treated and not treated with homeopathy were identified by internal transcribed space-polymerase chain reaction and investigated for the presence of the icaABCD, bap, aap, atlE, and bhp genes and in vitro biofilm production using the adhesion method on polystyrene plates. The enzyme restriction profile was determined by Pulsed-Field Gel Electrophoresis. Clusters of S. aureus and S. epidermidis with three or more isolates had an isolate selected for Multilocus Sequence Typing. RESULTS: The frequency of S. aureus isolations was similar in treated and untreated cows, while 71.4% of the coagulase-negative identified were isolated in cows treated with homeopathy. The distribution of the operon ica genes was similar in animals with and without treatment, except for the icaD gene, more frequent in treated cows. Production of biofilm was associated with presence of one or more genes from the icaADBC operon. S. aureus revealed a greater diversity and greater dissemination in cows treated and not treated with homeopathy. Sequence Types ST1, ST5, and ST126 were identified in S. aureus. CONCLUSIONS: The presence of biofilm-associated genes and the in vitro production of biofilms, combined with the persistence of clonal profiles of Staphylococcus spp. demonstrate other forms of control for bovine mastitis should be researched for organic production herds.

Assuntos

RESUMO

The aims of the study were (1) to compare the cure risk of intramammary treatment of pure platelet rich plasma (P-PRP) or cefquinome sulfate (CS) in cows with subclinical mastitis (SCM) caused by Gram-positive bacteria, evaluated via somatic cell count (SCC) and the microbiological analysis of milk; (2) to compare the inflammatory/anti-inflammatory response of mammary gland to both treatments through the analyses of interleukins (IL), interferon gamma (IFN-γ), and tumour necrosis factor alpha (TNF-α) in milk. A non-inferiority randomized clinical trial was conducted. The null hypothesis was that cure risk in the experimental group (P-PRP) was inferior to the reference group (CS). A total of 103 cows were selected according to SCC and presence of Gram-positive bacteria, 49 cows were treated with CS and 54 cows were treated with P-PRP after determination of its cellular and molecular quality control. Cure was assessed by milk analyses at day 21 and 22 after treatment. Cows that remained with SCM were retreated at day 26, and cure assessed at day 47 and 48. Overall, bacteriological cure was observed in 16 cows (30%) of the P-PRP group, and 35 cows (71%) in CS group. Staphylococcus aureus cure risk was higher in CS group, but inconclusive for Streptococcus spp. The mean SCC increased in relation to time only in the P-PRP group. A direct relation between time and treatment for IL-1, IL-2, and IL-6 was observed, while no differences were observed for IL-4. Furthermore, IL-1 and IL-2 increased in cows treated twice in both groups. IL-8, IFN-γ, and TNF-α showed a significant interaction between time and treatment. IFN-γ concentration was lower in the P-PRP group compared to the CS on days 0 and 22. Leukocyte counts were lower in P-PRP when compared to whole blood. TGF-ß1 and PF4 concentrations were higher in platelet lysates in comparison to P-PRGS and plasma. Moreover, PDGF-BB concentration was significantly higher in platelet lysates in comparison to plasma. Results obtained in this study demonstrate that SCM treated with PRP showed a lower rate of bacteriologic cure when compared to animals treated with CS.

Assuntos

RESUMO

In this research communication we address the hypothesis that a single intramammary infusion of casein hydrolyzate (CH) would have a similar effect to three intramammary infusions of CH for drying-off quarters with chronic mastitis (CM) during lactation. Sixty cows with CM were selected and randomly distributed into two treatment groups: (a) three intramammary CH infusions (100 mg, 50 ml per infusion, with 24-h intervals) or (b) single intramammary CH infusion (300 mg, 50 ml). Milk samples from the treated and untreated quarters were collected for microbiological culture and somatic cell count (SCC) before and after CH infusions. Milk yield was recorded and a manual pressure index measurement was used to evaluate cessation of lactation. Of the 60 quarters selected, 43 (71.67%) had positive microbiological culture. The quarters treated with three intramammary CH infusions had higher udder pressure index than those treated with single CH infusion. However, the average milk yield and composite SCC of three functional quarters were not different among treatments. Therefore, a single infusion of CH has the potential to be used as an alternative method for drying-off mammary quarters with CM during lactation.

Assuntos

RESUMO

Although, antibiotics are effective in the treatment of bovine mastitis, they do not address the regeneration of mammary glandular tissue and have been associated to the increment in antimicrobial resistance worldwide. Considering the necessity of alternative therapies for this disease of high economic impact and the reported regenerative and antibacterial effects of mesenchymal stem cell (MSCs), we evaluated the safety and efficacy of an allogenic MSC-based intramammary therapy in dairy cows with experimentally induced Staphylococcus aureus clinical mastitis. In a safety trial, heifers were inoculated intramammarily with a 2.5 × 107-suspension of bovine fetal AT-MSCs on experimental days 1 and 10. Animals were evaluated clinically on a daily basis during a 20-day experimental period and blood samples were collected for hemogram determination and peripheral blood leukocytes (PBLs) isolation. In an efficacy trial, Holstein Friesian cows were inoculated with S. aureus and treated intramammarily with vehicle (NEG; days 4 and 10), antibiotics (ATB; days 4 and 5) or a suspension of 2.5 × 107 AT-MSCs (MSC; days 4 and 5). Cows were clinically evaluated daily and milk samples were collected for somatic cell count (SCC) and colony forming units (CFU). Blood samples were collected for serum haptoglobin and amyloid A determination. Intramammary administration of two doses of bovine fetal AT-MSCs in healthy cows did not induce changes in clinical or hematological variables, and gene expression profiles in PBLs associated to activation (CD4, CD8, CD25, CD62L and CD69) and proinflammatory cytokines (CCL2, CCL5, IL2, CXCL3, IFNγ, and TNFα). Quarters of MSC group of cows had similar SCC log/mL in milk compared to infected quarters of ATB or NEG cows. However, quarters of MSC cows had lower CFU log/mL in milk compared to quarters of NEG cows. Intramammarily inoculation of repeated doses of 2.5 × 107 allogenic AT-MSCs did not induce clinical or immunological response in healthy cows. Moreover, MSC-intramammary treatment reduced bacterial count in milk of cows with S. aureus clinical mastitis compared to untreated cows. This work provides initial evidence for the safety and efficacy of an allogenic MSC-based intramammary therapy for the treatment of bovine mastitis.

Assuntos

RESUMO

Mesenchymal stem cells have been widely used in the treatment of various chronic diseases. The objective of this survey was to evaluate the therapeutic and regenerative potential of stem cells from adipose tissue (ASCs) in the milk production recovery repair of tissue injury in mastitis goats treated with antimicrobial agents prior to cell therapy. After the diagnosis of mastitis and treatment with gentamicin, eight lactating goats were selected for cellular and subsequent therapy, physical-chemical analysis of milk, ultrasonographic and histopathological examinations. The ASCs were taken from the subcutaneous fat of a young goat cultivated in vitro, marked with Qdots-655 and injected in the left mammary gland, being the right mammary gland used as the control. After 30 days the ultrasonographic and histopathological analyzes were repeated and, in the first lactation period, the physical-chemical analysis of the milk was reapeated. Before the cellular therapy, the physical-chemical quality of the milk was compromised and the ultrasonographic and histopathological analysis revealed a chronic inflammatory process and fibrous tissue. The marking of the ASCs with Qdots enabled the tracking, by fluorescence microscopy (BX41-OLYMPUS), in the mammary tissue. In the ASCs therapy, cultures showed high cellularity and characteristics favorable to preclinical studies; with the therapy the physical-chemical parameters of the milk, fat, protein, temperature and pH showed significant differences among the groups; five animals treated with ASCs reconstituted the functionality of the gland and the connective tissue reduced in quantity and inflammatory infiltrate cells. ASCs have potential for the possible regeneration of fibrous mastitis lesions in the mammary gland, however, it would be necessary to increase injection time for the histopathological analysis, since the reconstitution of the glandular acini within the assessed period was not finalized. ASCs can be used to reestablish milk production in goat with chronic mastitis repair mammary lesions, with potential to be a promising clinical alternative for animal rehabilitation for productivity.

Assuntos

RESUMO

Bovine mastitis remains the main cause of economic losses for dairy farmers. Mammary pathogenic Escherichia coli (MPEC) is related to an acute mastitis and its treatment is still based on the use of antibiotics. In the era of antimicrobial resistance (AMR), bacterial viruses (bacteriophages) present as an efficient treatment or prophylactic option. However, this makes it essential that its genetic structure, stability and interaction with the host immune system be thoroughly characterized. The present study analyzed a novel, broad host-range anti-mastitis agent, the T4virus vB_EcoM-UFV13 in genomic terms, and its activity against a MPEC strain in an experimental E. coli-induced mastitis mouse model. 4,975 Single Nucleotide Polymorphisms (SNPs) were assigned between vB_EcoM-UFV13 and E. coli phage T4 genomes with high impact on coding sequences (CDS) (37.60%) for virion proteins. Phylogenetic trees and genome analysis supported a recent infection mix between vB_EcoM-UFV13 and Shigella phage Shfl2. After a viral stability evaluation (e.g pH and temperature), intramammary administration (MOI 10) resulted in a 10-fold reduction in bacterial load. Furthermore, pro-inflammatory cytokines, such as IL-6 and TNF-α, were observed after viral treatment. This work brings the whole characterization and immune response to vB_EcoM-UFV13, a biocontrol candidate for bovine mastitis.

Assuntos

RESUMO

The objective of this study was to assess the control feasibility of Streptococcus agalactiae subclinical mastitis and its impact in reducing somatic cell counts (SCC) of bulk milk tank. During the lactation, 33 cows positive for Streptococcus agalactiae in microbiological culture were treated with three applications of intramammary antimicrobial containing 100.000 UI of penicillin and 150 mg of novobiocin, in an interval of 12 hours. Individual and bulk tank milk samples were collected for somatic cell count (SCC) analysis and milk yield was measured before and after treatment. Statistical analyses were performed with SAS System, version 9.2. All cows treated against S. agalactiae had microbiological cure and reduction of SCC, indicating the effectiveness of treatment. SCC in bulk tank was reduced from 829,000 to 513,000 cells/ml.(AU)

Assuntos

RESUMO

The objective of this study was to assess the control feasibility of Streptococcus agalactiae subclinical mastitis and its impact in reducing somatic cell counts (SCC) of bulk milk tank. During the lactation, 33 cows positive for Streptococcus agalactiae in microbiological culture were treated with three applications of intramammary antimicrobial containing 100.000 UI of penicillin and 150 mg of novobiocin, in an interval of 12 hours. Individual and bulk tank milk samples were collected for somatic cell count (SCC) analysis and milk yield was measured before and after treatment. Statistical analyses were performed with SAS System, version 9.2. All cows treated against S. agalactiae had microbiological cure and reduction of SCC, indicating the effectiveness of treatment. SCC in bulk tank was reduced from 829,000 to 513,000 cells/ml.

Assuntos

RESUMO

The antimicrobial activities of the oleoresin (OR) and the essential oil (EO) of Copaifera spp. were checked against microorganisms isolated from milk samples of cows diagnosed with grade III subclinical mastitis. The OR had good antimicrobial activity (MIC < = 100 µg/mL) against samples of coagulase-positive Staphylococcus, coagulase-negative Staphylococcus, Streptococcus of groups C, F, and G, andCorynebacterium spp. Meanwhile, the EO had good antimicrobial activity (MIC < = 100 µg/mL) against coagulase-negative Staphylococcus and Corynebacterium spp. The OR and the EO were inactive and weak to inactive, respectively, against Escherichia coli. Overall, the OR had better antimicrobial activity than the essential oil against the 55 bacterial isolates (p < 0.0001). The GC/MS analysis identified sesquiterpenes in EO and by the ESI FT-ICR MS method, the identification of diterpenic acids in OR was possible. Therefore, this raw plant material is promising for the development of phytotherapeutic drugs against bovine mastitis.(AU)

A mastite bovina é um problema sanitário que afeta o gado leiteiro em todas as áreas produtoras do mundo, sendo de difícil controle e erradicação. A atividade antimicrobiana da oleorresina e do óleo essencial de Copaifera spp. foi verificada frente aos micro-organismos isolados de amostras de leite de vacas diagnosticadas com mastite subclínica grau III. A oleorresina de Copaifera ssp. apresentou boa atividade antimicrobiana (CIM < = 100 µg/mL) frente às amostras de Staphylococcus coagulase positivo,Staphylococcus coagulase negativo, Streptococcus do grupo C, F, G e Corynebacterium spp. Já o óleo essencial de Copaifera spp. apresentou boa atividade antimicrobiana (CIM < = 100 µg/mL) frente aosStaphylococcus coagulase negativo e Corynebacterium spp. Em relação à Escherichia coli, a atividade antimicrobiana da oleorresina e o óleo essencial foi inativa e fraca à inativa, respectivamente. Conclui-se que, frente às 55 bactérias isoladas, a olerresina apresentou melhor atividade antimicrobiana do que o óleo essencial de Copaifera spp. (p < 0,0001). A análise por CG/EM identificou sesquiterpenos no óleo essencial e pelo método ESI FT-ICR MS, foi possível identificar ácidos diterpenos na oleorresina de Copaifera spp. Por fim, sugere-se que a oleorresina de Copaifera spp. é uma matéria-prima vegetal promissora no desenvolvimento de medicamento fitoterápico para o tratamento de mastite bovina.(AU)

Assuntos

RESUMO

The antimicrobial activities of the oleoresin (OR) and the essential oil (EO) of Copaifera spp. were checked against microorganisms isolated from milk samples of cows diagnosed with grade III subclinical mastitis. The OR had good antimicrobial activity (MIC < = 100 µg/mL) against samples of coagulase-positive Staphylococcus, coagulase-negative Staphylococcus, Streptococcus of groups C, F, and G, andCorynebacterium spp. Meanwhile, the EO had good antimicrobial activity (MIC < = 100 µg/mL) against coagulase-negative Staphylococcus and Corynebacterium spp. The OR and the EO were inactive and weak to inactive, respectively, against Escherichia coli. Overall, the OR had better antimicrobial activity than the essential oil against the 55 bacterial isolates (p < 0.0001). The GC/MS analysis identified sesquiterpenes in EO and by the ESI FT-ICR MS method, the identification of diterpenic acids in OR was possible. Therefore, this raw plant material is promising for the development of phytotherapeutic drugs against bovine mastitis.

A mastite bovina é um problema sanitário que afeta o gado leiteiro em todas as áreas produtoras do mundo, sendo de difícil controle e erradicação. A atividade antimicrobiana da oleorresina e do óleo essencial de Copaifera spp. foi verificada frente aos micro-organismos isolados de amostras de leite de vacas diagnosticadas com mastite subclínica grau III. A oleorresina de Copaifera ssp. apresentou boa atividade antimicrobiana (CIM < = 100 µg/mL) frente às amostras de Staphylococcus coagulase positivo,Staphylococcus coagulase negativo, Streptococcus do grupo C, F, G e Corynebacterium spp. Já o óleo essencial de Copaifera spp. apresentou boa atividade antimicrobiana (CIM < = 100 µg/mL) frente aosStaphylococcus coagulase negativo e Corynebacterium spp. Em relação à Escherichia coli, a atividade antimicrobiana da oleorresina e o óleo essencial foi inativa e fraca à inativa, respectivamente. Conclui-se que, frente às 55 bactérias isoladas, a olerresina apresentou melhor atividade antimicrobiana do que o óleo essencial de Copaifera spp. (p < 0,0001). A análise por CG/EM identificou sesquiterpenos no óleo essencial e pelo método ESI FT-ICR MS, foi possível identificar ácidos diterpenos na oleorresina de Copaifera spp. Por fim, sugere-se que a oleorresina de Copaifera spp. é uma matéria-prima vegetal promissora no desenvolvimento de medicamento fitoterápico para o tratamento de mastite bovina.

Assuntos

RESUMO

The study evaluated the microbiological profile of milk samples collected before and after mastitis treatment with gentamicin and investigated biofilms production and antimicrobial susceptibility of Staphylococcus spp. isolated. The presence of gentamicin residues in milk after the recommended withdrawal period was also evaluated. Antimicrobial residues were analyzed by Delvotest® SP NT over a period of 12 days beginning after 24 hours the last gentamicin application. Some of Staphylococcus spp. isolates were biofilm producers (19.05%). Staphylococcus spp. showed high levels of resistance to neomycin (16.95%), penicillin G (10.17%), and ampicillin (10.17%). Multidrug resistance to all antibiotics tested was observed in 1.69% of the Staphylococcus spp. isolates. Among 1440 mammary quarter milk samples 24.95% presented gentamicin residues after the withdrawal period. Gentamicin residues were also detected in 3.8% of samples from calibrated glass recorder jar (n=383) 4.1 days after treatment. The indiscriminate use of antibiotics may lead to the emergence of multidrug-resistant strains as well as increasing the risk of presence of residues of these drugs in milk. These problems affect the milk quality and may become a public health problem.

Este estudo avaliou o perfil microbiológico de amostras de leite colhidas antes e após o tratamento da mastite com gentamicina e investigou a produção de biofilmes e o perfil de susceptibilidade antimicrobiana de Staphylococcus spp. isolados. Avaliou-se também a presença de resíduos de gentamicina no leite após o período de carência recomendado. Resíduos de antimicrobianos foram analisados por Delvotest® SP NT ao longo de um período de 12 dias, iniciando 24 horas após a última aplicação de gentamicina. Alguns dos Staphylococcus spp. isolados apresentaram produção de biofilmes (19,05%). Staphylococcus spp. apresentaram elevados níveis de resistência à neomicina (16,95%), penicilina G (10,17%), e ampicilina (10.17%). Multirresistência a todos os antibióticos testados foi observada em 1,69% dos Staphylococcus spp. isolados. Do total de 1440 amostras de leite de quartos mamários, 24,95% apresentaram resíduos de gentamicina após o período de carência. Resíduos de gentamicina também foram detectados em 3,8% das amostras de balões volumétricos coletores de leite (n= 383), 4,1 dias após o tratamento. O uso indiscriminado de antibióticos pode levar ao aparecimento de estirpes multirresistentes bem como o aumento do risco da presença de resíduos destas drogas no leite. Esses problemas afetam a qualidade do leite e podem tornar-se um problema de saúde pública.

Assuntos

RESUMO

The study evaluated the microbiological profile of milk samples collected before and after mastitis treatment with gentamicin and investigated biofilms production and antimicrobial susceptibility of Staphylococcus spp. isolated. The presence of gentamicin residues in milk after the recommended withdrawal period was also evaluated. Antimicrobial residues were analyzed by Delvotest® SP NT over a period of 12 days beginning after 24 hours the last gentamicin application. Some of Staphylococcus spp. isolates were biofilm producers (19.05%). Staphylococcus spp. showed high levels of resistance to neomycin (16.95%), penicillin G (10.17%), and ampicillin (10.17%). Multidrug resistance to all antibiotics tested was observed in 1.69% of the Staphylococcus spp. isolates. Among 1440 mammary quarter milk samples 24.95% presented gentamicin residues after the withdrawal period. Gentamicin residues were also detected in 3.8% of samples from calibrated glass recorder jar (n=383) 4.1 days after treatment. The indiscriminate use of antibiotics may lead to the emergence of multidrug-resistant strains as well as increasing the risk of presence of residues of these drugs in milk. These problems affect the milk quality and may become a public health problem.(AU)

Este estudo avaliou o perfil microbiológico de amostras de leite colhidas antes e após o tratamento da mastite com gentamicina e investigou a produção de biofilmes e o perfil de susceptibilidade antimicrobiana de Staphylococcus spp. isolados. Avaliou-se também a presença de resíduos de gentamicina no leite após o período de carência recomendado. Resíduos de antimicrobianos foram analisados por Delvotest® SP NT ao longo de um período de 12 dias, iniciando 24 horas após a última aplicação de gentamicina. Alguns dos Staphylococcus spp. isolados apresentaram produção de biofilmes (19,05%). Staphylococcus spp. apresentaram elevados níveis de resistência à neomicina (16,95%), penicilina G (10,17%), e ampicilina (10.17%). Multirresistência a todos os antibióticos testados foi observada em 1,69% dos Staphylococcus spp. isolados. Do total de 1440 amostras de leite de quartos mamários, 24,95% apresentaram resíduos de gentamicina após o período de carência. Resíduos de gentamicina também foram detectados em 3,8% das amostras de balões volumétricos coletores de leite (n= 383), 4,1 dias após o tratamento. O uso indiscriminado de antibióticos pode levar ao aparecimento de estirpes multirresistentes bem como o aumento do risco da presença de resíduos destas drogas no leite. Esses problemas afetam a qualidade do leite e podem tornar-se um problema de saúde pública.(AU)

Assuntos

RESUMO

o objetivo desta pesquisa foi avaliar o efeito antimicrobiano de extratos obtidos de plantas desidratadas e própolis contra estirpes de Staphylococcus aureus isoladas de leite cru granelizado, coletado na zona rural de Rio Pomba, MG. Foi avaliada a atividade antimicrobiana dos extratos de alho, aroeira, confrei, alecrim, mandioca, terramicina, calêndula, salsa, orégano e própolis frente a 29 estirpes de S. aureus por meio de difusão em Ágar Mueller-Hinton. Discos de papel foram embebidos nos extratos e transferidos para placas previamente inoculadas com as estirpes de S. aureus. Foi adotado o método de agrupamento aos pares utilizando médias aritméticas e o teste de Scott-Knott ao nível de 5% de probabilidade na avaliação dos resultados obtidos. Os extratos de aroeira e orégano foram efetivos contra todos os isolados de S. aureus. Os demais extratos apresentaram diâmetro do halo de inibição reduzido para a maioria dos isolados testados. Contudo, são necessárias pesquisas visando determinar os mecanismos de ação e a dose efetivados extratos de aroeira e orégano a fim de desenvolver tecnologias adequadas e úteis no controle da mastite.(AU)

The aim of this study was to evaluate the antimicrobial effect of dried plant extracts and propolis against strains of Staphylococcus aureus isolated from bulk raw milk of Rio Pomba, MG. The methodology involved the assessment of antimicrobial activity of extracts of garlic, pepper tree, comfrey, rosemary, yucca, terramycin, marigold, parsley, oregano and propolis against 29 strains of S. aureus by Mueller-Hinton Agar diffusion. Paper discs were soaked into extracts and transferred to plates previously inoculated with strains of S. aureus. It was used the Pairwise Clustering Method Using Arithmetic Averages and Scott-Knott test at 5% probability to evaluation of obtained results. Extracts of pepper tree and oregano were effective against all strains of S. aureus. The other extracts showed inhibition zone diameter reduced for most of the isolates tested. Therefore, more studies are needed to determine the mechanisms of action and effective dose of pepper tree and oregano extracts in order to develop appropriated technologies to control bovine mastitis.(AU)

Assuntos

Assuntos

RESUMO

The objective of this study was to evaluate herd management practices and mastitis treatment procedures as risk factors associated with Staphylococcus aureus antimicrobial resistance. For this study, 13 herds were selected to participate in the study to evaluate the association between their management practices and mastitis treatment procedures and in vitro antimicrobial susceptibility. A total of 1069 composite milk samples were collected aseptically from the selected cows in four different periods over two years. The samples were used for microbiological culturing of S. aureus isolates and evaluation of their antimicrobial susceptibility. A total of 756 samples (70.7%) were culture-positive, and S. aureus comprised 27.77% (n=210) of the isolates. The S. aureus isolates were tested using the disk-diffusion susceptibility assay with the following antimicrobials: ampicillin 10mg; clindamycin 2μg; penicillin 1mg; ceftiofur 30μg; gentamicin 10mg; sulfa-trimethoprim 25μg; enrofloxacin 5μg; sulfonamide 300μg; tetracycline 30μg; oxacillin 1mg; cephalothin 30μg and erythromycin 5μg. The variables that were significantly associated with S. aureus resistance were as follows: the treatment of clinical mastitis for ampicillin (OR=2.18), dry cow treatment for enrofloxacin (OR=2.11) and not sending milk samples for microbiological culture and susceptibility tests, for ampicillin (OR=2.57) and penicillin (OR=4.69). In conclusion, the identification of risk factors for S. aureus resistance against various mastitis antimicrobials is an important information that may help in practical recommendations for prudent use of antimicrobial in milk production.

Objetivou-se com este estudo avaliar os fatores de risco associados às práticas de manejo e tratamento de mastite e a resistência aos antimicrobianos de Staphylococcus aureus isolados de vacas com mastite. Foram selecionados para o presente estudo 13 rebanhos localizados na região de Pirassununga/SP. Foi aplicado um questionário contendo informações para o levantamento de fatores de risco relacionados à resistência aos antimicrobianos e às práticas de manejo e tratamento de mastite. Após a seleção dos rebanhos e aplicação dos questionários, foram utilizados 210 isolados de S. aureus de amostras compostas de leite coletadas durante 24 meses, em quatro períodos, para realização dos testes de resistência. Os antimicrobianos testados foram: ampicilina 10µg, clindamicina 2µg, penicilina 1µg, eftiofour 30µg, gentamicina 10µg, sulfatrimetropin 25µg, enrofloxacina 5µg, sulfonamida 300µg, tetraciclina 30µg, oxacilina 1µg, cefalotina 30µg e eritromicina 5µg. As variáveis que foram significativamente associadas à resistência de S. aureus foram: o tratamento da mastite clínica para ampicilina (OR = 2,18), o tratamento da vaca seca para enrofloxacina (OR=2,11), e o não envio de amostras de leite para a cultura microbiológica e testes de sensibilidade, para ampicilina (OR=2,57) e penicilina (OR=4,69). Em conclusão, a identificação dos fatores de risco para a resistência S. aureus frente aos principais agentes antimicrobianos, utilizados para tratamento da mastite, pode auxiliar o estabelecimento do uso prudente de antimicrobianos na produção de leite.

Assuntos

RESUMO

The objective of this study was to evaluate herd management practices and mastitis treatment procedures as risk factors associated with Staphylococcus aureus antimicrobial resistance. For this study, 13 herds were selected to participate in the study to evaluate the association between their management practices and mastitis treatment procedures and in vitro antimicrobial susceptibility. A total of 1069 composite milk samples were collected aseptically from the selected cows in four different periods over two years. The samples were used for microbiological culturing of S. aureus isolates and evaluation of their antimicrobial susceptibility. A total of 756 samples (70.7%) were culture-positive, and S. aureus comprised 27.77% (n=210) of the isolates. The S. aureus isolates were tested using the disk-diffusion susceptibility assay with the following antimicrobials: ampicillin 10mg; clindamycin 2μg; penicillin 1mg; ceftiofur 30μg; gentamicin 10mg; sulfa-trimethoprim 25μg; enrofloxacin 5μg; sulfonamide 300μg; tetracycline 30μg; oxacillin 1mg; cephalothin 30μg and erythromycin 5μg. The variables that were significantly associated with S. aureus resistance were as follows: the treatment of clinical mastitis for ampicillin (OR=2.18), dry cow treatment for enrofloxacin (OR=2.11) and not sending milk samples for microbiological culture and susceptibility tests, for ampicillin (OR=2.57) and penicillin (OR=4.69). In conclusion, the identification of risk factors for S. aureus resistance against various mastitis antimicrobials is an important information that may help in practical recommendations for prudent use of antimicrobial in milk production.(AU)

Objetivou-se com este estudo avaliar os fatores de risco associados às práticas de manejo e tratamento de mastite e a resistência aos antimicrobianos de Staphylococcus aureus isolados de vacas com mastite. Foram selecionados para o presente estudo 13 rebanhos localizados na região de Pirassununga/SP. Foi aplicado um questionário contendo informações para o levantamento de fatores de risco relacionados à resistência aos antimicrobianos e às práticas de manejo e tratamento de mastite. Após a seleção dos rebanhos e aplicação dos questionários, foram utilizados 210 isolados de S. aureus de amostras compostas de leite coletadas durante 24 meses, em quatro períodos, para realização dos testes de resistência. Os antimicrobianos testados foram: ampicilina 10µg, clindamicina 2µg, penicilina 1µg, eftiofour 30µg, gentamicina 10µg, sulfatrimetropin 25µg, enrofloxacina 5µg, sulfonamida 300µg, tetraciclina 30µg, oxacilina 1µg, cefalotina 30µg e eritromicina 5µg. As variáveis que foram significativamente associadas à resistência de S. aureus foram: o tratamento da mastite clínica para ampicilina (OR = 2,18), o tratamento da vaca seca para enrofloxacina (OR=2,11), e o não envio de amostras de leite para a cultura microbiológica e testes de sensibilidade, para ampicilina (OR=2,57) e penicilina (OR=4,69). Em conclusão, a identificação dos fatores de risco para a resistência S. aureus frente aos principais agentes antimicrobianos, utilizados para tratamento da mastite, pode auxiliar o estabelecimento do uso prudente de antimicrobianos na produção de leite.(AU)

Assuntos

RESUMO

As mastites estão entre as principais causas de prejuízo para produtores de leite. Em casos graves de hiperqueratose, o canal do teto pode se tornar uma barreira mais fácil para que as bactérias penetrem na glândula mamária. Os objetivos deste estudo foram avaliar um dispositivo fotobiomodulador de LED para tratamento e prevenção de hiperqueratose de teto e prevenção da mastite subclínica em um rebanho de leite com alta prevalência de hiperqueratose (35,3 por cento de casos graves). Foram utilizadas 60 primíparas para o experimento de prevenção e 30 vacas com hiperqueratose para o experimento terapêutico. Em ambos os experimentos, metade dos animais foram tratados com o dispositivo fotobiomodulador três vezes por semana, durante 6 semanas. Os outros animais foram os controles. Imagens fotográficas digitalizadas foram realizadas na avaliação inicial e, semanalmente, por 6 semanas consecutivas. Nas primíparas, novas avaliações foram realizadas entre 6 e 7 meses de lactação. Para avaliação da mastite subclínica, contagem de células somáticas (CCS) foram feitas mensalmente. No experimento preventivo, o diâmetro externo das lesões permaneceu constante nos tetos do grupo tratado, enquanto houve aumento no grupo controle. No experimento terapêutico não foram observadas diferenças estatísticas entre as variáveis de hiperqueratose. Contudo, o grupo tratado apresentou menor incidência de mastites subclínicas (CCS < 250 células/mL) por lactação do que o grupo controle (P<0,05). Em conclusão, o tratamento não foi efetivo em prevenir o desenvolvimento ou reduzir lesões instaladas de hiperqueratose de teto. Contudo, o uso protótipo se mostrou útil e promissor como adjuvante na prevenção do aumento de tamanho das lesões de hiperqueratose de teto em primíparas e como forma de reduzir incidência de mastite subclínicas em vacas leiteiras já acometidas.

Mastitis consistis one of the main problems of milk production, mainly due to the production losses and the rising cost of milk. In case of severe hyperkeratosis, the teat canal can become an easier barrier for the bacteria to penetrate. The objeSctive of this study was to assess a phototherapy device construct with LED light for prevention and treatment of teat hyperkeratosis in a dairy cattle herd with high prevalence (35.3 percent of severe cases). 60 primiparous cows were used in the preventive experiment and 30 cows with hyperkeratosis were used in the therapeutic experiment. In both experiments, half of the cows started to be treated in early lactation using the phototherapy device three times per week for 6 weeks. The other cows were the controls. Hyperkeratosis was assessed by scoring and by morphometric analyses of teat images that were taken at baseline and then weekly for 6 consecutive weeks. In the preventive experiment, more images were taken later, between 6 and 7 months of the first lactation. Somatic cell counts (SCC) were performed monthly. In the preventive experiment, the outer diameter of the teat lesions remained constant in the treated group, whereas cows of the control group showed a significant increase at the end of lactation. In the therapeutic groups, no statistical differences for teat hyperkeratosis variables were seen between groups. However, the incidence of subclinical mastitis (SCC > 250 cells/mL) during lactation was lower in the treated group (P<0.05). In conclusion the phototherapy protocol did not prevent the development in primiparous or ameliorate previous hyperkeratosis lesions in cows. However, the prototype was considered useful as an adjunct in preventing the increase in the size of teat hyperkeratosis lesions and also as a way to reduce subclinical mastitis incidence in affected dairy cows.

Assuntos

RESUMO

As mastites estão entre as principais causas de prejuízo para produtores de leite. Em casos graves de hiperqueratose, o canal do teto pode se tornar uma barreira mais fácil para que as bactérias penetrem na glândula mamária. Os objetivos deste estudo foram avaliar um dispositivo fotobiomodulador de LED para tratamento e prevenção de hiperqueratose de teto e prevenção da mastite subclínica em um rebanho de leite com alta prevalência de hiperqueratose (35,3 por cento de casos graves). Foram utilizadas 60 primíparas para o experimento de prevenção e 30 vacas com hiperqueratose para o experimento terapêutico. Em ambos os experimentos, metade dos animais foram tratados com o dispositivo fotobiomodulador três vezes por semana, durante 6 semanas. Os outros animais foram os controles. Imagens fotográficas digitalizadas foram realizadas na avaliação inicial e, semanalmente, por 6 semanas consecutivas. Nas primíparas, novas avaliações foram realizadas entre 6 e 7 meses de lactação. Para avaliação da mastite subclínica, contagem de células somáticas (CCS) foram feitas mensalmente. No experimento preventivo, o diâmetro externo das lesões permaneceu constante nos tetos do grupo tratado, enquanto houve aumento no grupo controle. No experimento terapêutico não foram observadas diferenças estatísticas entre as variáveis de hiperqueratose. Contudo, o grupo tratado apresentou menor incidência de mastites subclínicas (CCS < 250 células/mL) por lactação do que o grupo controle (P<0,05). Em conclusão, o tratamento não foi efetivo em prevenir o desenvolvimento ou reduzir lesões instaladas de hiperqueratose de teto. Contudo, o uso protótipo se mostrou útil e promissor como adjuvante na prevenção do aumento de tamanho das lesões de hiperqueratose de teto em primíparas e como forma de reduzir incidência de mastite subclínicas em vacas leiteiras já acometidas.(AU)

Mastitis consistis one of the main problems of milk production, mainly due to the production losses and the rising cost of milk. In case of severe hyperkeratosis, the teat canal can become an easier barrier for the bacteria to penetrate. The objeSctive of this study was to assess a phototherapy device construct with LED light for prevention and treatment of teat hyperkeratosis in a dairy cattle herd with high prevalence (35.3 percent of severe cases). 60 primiparous cows were used in the preventive experiment and 30 cows with hyperkeratosis were used in the therapeutic experiment. In both experiments, half of the cows started to be treated in early lactation using the phototherapy device three times per week for 6 weeks. The other cows were the controls. Hyperkeratosis was assessed by scoring and by morphometric analyses of teat images that were taken at baseline and then weekly for 6 consecutive weeks. In the preventive experiment, more images were taken later, between 6 and 7 months of the first lactation. Somatic cell counts (SCC) were performed monthly. In the preventive experiment, the outer diameter of the teat lesions remained constant in the treated group, whereas cows of the control group showed a significant increase at the end of lactation. In the therapeutic groups, no statistical differences for teat hyperkeratosis variables were seen between groups. However, the incidence of subclinical mastitis (SCC > 250 cells/mL) during lactation was lower in the treated group (P<0.05). In conclusion the phototherapy protocol did not prevent the development in primiparous or ameliorate previous hyperkeratosis lesions in cows. However, the prototype was considered useful as an adjunct in preventing the increase in the size of teat hyperkeratosis lesions and also as a way to reduce subclinical mastitis incidence in affected dairy cows.(AU)

Assuntos