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The aim of this study was to determine whether the addition of a homeopathic product to dairy cow feed would improve health and production efficiency, as well as composition and quality of milk. The product tested here was produced to stimulate immunity and indirectly to prevent the colonization of the mammary gland by bacteria, thereby decreasing somatic cell counts and bacteria in cow’s milk. Fifty dairy cows were used, divided into two groups: Control (n = 25) and Treated (n = 25). For 90 consecutive days, 50 grams of homeopathic product (treated group) was added to the concentrate; 50 g of the product vehicle (limestone) was added to the concentrate of the control cows. We performed composition and quality analysis on the milk (days 1, 15, 30, 45, 60, 75, and 90) as well as blood collection to carry out hematological and metabolism analyses (days 1, 30, 60, and 90). We found that fat content in the milk cows consuming the homeopathic agent was greater than that of the control group. Because of this increased fat content, there was a tendency towards higher total solids content in treated cows. A treatment effect was found in terms of total bacterial count (TBC); that is, there were lower TBCs in milk of treated animals than in control animals. There was a trend of a treatment effect versus day for somatic cell count (SCC); that is, there were lower SCC in animals that consumed the homeopathic on days 15 and 30 of the experiment. There was no difference between groups in terms of milk production; however, there was a negative correlation between milk production and TBC or SCC in the milk of cows that consumed homeopathic product. Animals in the treated group had lower total leukocyte and lymphocyte counts than did the control group, as well as a tendency toward lower neutrophil counts in these animals. Several bacteria were isolated from the cows' milk during the experimental period, with no treatment effect. In particular, we isolated Corynebacterium spp., Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus hyicus in greater numbers of cows compared to other etiologic agents. Based on these results, we conclude that consumption of the homeopathic product by dairy cows had positive effects on milk quality. El objetivo de este estudio fue determinar si la adición de un producto homeopático a la alimentación de las vacas lecheras mejoraría la salud y la eficiencia de producción, así como la composición y calidad de la leche. El producto probado aquí fue producido para estimular la inmunidad e indirectamente para prevenir la colonización de la glándula mamaria por bacterias, disminuyendo así el recuento de células somáticas y bacterias en la leche de vaca. Se utilizaron cincuenta vacas lecheras, divididas en dos grupos: Control (n = 25) y Tratadas (n = 25). Durante 90 días consecutivos, se añadieron al concentrado 50 gramos de producto homeopático (grupo tratado); Se añadieron 50 g del vehículo producto (piedra caliza) al concentrado de las vacas de control. Realizamos análisis de composición y calidad de la leche (días 1, 15, 30, 45, 60, 75 y 90) así como extracción de sangre para realizar análisis hematológicos y metabólicos (días 1, 30, 60 y 90). Encontramos que el contenido de grasa en las vacas lecheras que consumían el agente homeopático era mayor que el del grupo de control. Debido a este mayor contenido de grasa, hubo una tendencia hacia un mayor contenido de sólidos totales en las vacas tratadas. Se encontró un efecto del tratamiento en términos de recuento bacteriano total (RBT); es decir, hubo RBT más bajos en la leche de los animales tratados que en los animales de control. Hubo una tendencia de un efecto del tratamiento frente al día para el recuento de células somáticas (RCS); es decir, hubo menor RCS en los animales que consumieron el homeopático los días 15 y 30 del experimento. No hubo diferencia entre los grupos en términos de producción de leche; sin embargo, hubo una correlación negativa entre la producción de leche y RBT o RCS en la leche de las vacas que consumieron productos homeopáticos. Los animales del grupo tratado tenían recuentos de leucocitos y linfocitos totales más bajos que el grupo de control, así como una tendencia hacia recuentos de neutrófilos más bajos en estos animales. Se aislaron varias bacterias de la leche de vaca durante el período experimental, sin efecto del tratamiento. En particular, aislamos Corynebacterium spp., Staphylococcus aureus, Staphylococcus epidermidis y Staphylococcus hyicus en un mayor número de vacas en comparación con otros agentes etiológicos. Con base en estos resultados, concluimos que el consumo del producto homeopático por las vacas lecheras tuvo efectos positivos sobre la calidad de la leche. O objetivo deste estudo foi determinar se a adição de um produto homeopático à ração para vacas leiteiras melhoraria a saúde e a eficiência da produção, bem como a composição e qualidade do leite. O produto testado aqui foi produzido para estimular a imunidade e indiretamente para prevenir a colonização da glândula mamária por bactérias, diminuindo assim a contagem de células somáticas e bactérias no leite de vaca. Foram utilizadas 50 vacas leiteiras, divididas em dois grupos: Controle (n = 25) e Tratada (n = 25). Por 90 dias consecutivos, 50 gramas do produto homeopático (grupo tratado) foram adicionados ao concentrado; 50 g do veículo produto (calcário) foram adicionados ao concentrado das vacas controle. Foram realizadas análises de composição e qualidade do leite (dias 1, 15, 30, 45, 60, 75 e 90), bem como coleta de sangue para realização de análises hematológicas e metabólicas (dias 1, 30, 60 e 90). Descobrimos que o teor de gordura nas vacas leiteiras que consumiam o agente homeopático era maior do que no grupo controle. Devido ao aumento do teor de gordura, houve uma tendência de maior teor de sólidos totais nas vacas tratadas. Um efeito do tratamento foi encontrado em termos de contagem bacteriana total (CBT); ou seja, houve menor CBT no leite dos animais tratados do que nos animais controle. Houve uma tendência de efeito do tratamento versus dia para contagem de células somáticas (CCS); ou seja, houve menor CCS nos animais que consumiram o homeopático nos dias 15 e 30 do experimento. Não houve diferença entre os grupos em termos de produção de leite; entretanto, houve uma correlação negativa entre a produção de leite e CBT ou CCS no leite de vacas que consumiram produtos homeopáticos. Os animais do grupo tratado apresentaram menor contagem total de leucócitos e linfócitos do que o grupo controle, bem como tendência para menor contagem de neutrófilos nesses animais. Várias bactérias foram isoladas do leite de vaca durante o período experimental, sem efeito do tratamento. Em particular, isolamos Corynebacterium spp., Staphylococcus aureus, Staphylococcus epidermidis e Staphylococcus hyicus em maior número de vacas em comparação com outros agentes etiológicos. Com base nesses resultados, concluímos que o consumo do produto homeopático por vacas leiteiras teve efeitos positivos na qualidade do leite.

Despite the vast literature on postpartum mastitis in cattle, there is a demand for and lack of studies on the cellularity dynamics and cellular populations in milk and the occurrence of mastitis in ewes during the postpartum period. Thus, the aim of the present study was to evaluate the dynamics of cellularity in milk/colostrum and of mastitis in primiparous and multiparous Lacaune ewes during early lactation. For this purpose, 492 milk/colostrum samples were collected from the udder halves of 20 primiparous ewes and 21 multiparous ewes at the following six time points: day of parturition (T1) and one day (T2), three days (T3), seven days (T4), 15 days (T5), and 30 days (T6) after parturition. The milk and colostrum samples were subjected to microbiological examination, microscopic and automatic somatic cell counts (SCCs), differential somatic cell counts, and the California Mastitis test (CMT). The multiparous ewes had a higher prevalence of intramammary infections than the primiparous ewes during the postpartum period. Non-aureus staphylococci bacteria were the main mastitis etiological agents isolated in the present study. Furthermore, one of the most important findings of our study was that 35% of the udder halves of the primiparous ewes were infected at parturition, suggesting potential concerns for mastitis control programs. Finally, the SCC did not appear to be a good indicator of inflammation during early lactation because this measure was influenced by the parity and the sampling period. Moreover, the predictive values of the CMT and neutrophil counts were slightly better than those of the SCC during the immediate postpartum period.

Objective: To assess the microbiological profile in seven Boar Studs (BS) in Southern Brazil, as well as evaluate antimicrobial susceptibility response to most commonly found microorganisms in BS. Material and methods: Bacteriologic analysis was carried out in samples from the water purification system, semen extender, raw and stored semen, lab benches, and other working surfaces. Results: Growth of a mixed bacterial population was observed in water samples from all but one BS. Approximately 85% of the BS had significant contamination on their working surfaces with at least one bacterial contaminant. A total of 86% of raw semen samples were contaminated with one or more different bacteria, while 100% of the boar studs provided contaminated samples. Bacterial susceptibility to antimicrobial agents varied from over 80% for gentamycin, neomycin and ceftiofur to 40% or less for penicillin and lincomycin. Conclusions: The identification of the critical points provides necessary support to devise better strategies to minimize contamination in BS. Also, assessing the level of antimicrobial drug resistance offers accurate information to formulate more efficient antibacterial protocols that closely observe the rational use of antibiotics., Objectivo: Evaluar el perfil microbiológico de siete centros de recogida de semen porcino (CRSP) en el sur de Brasil, así como evaluar la susceptibilidad antimicrobiana a la mayoría de los microorganismos encontrados en los CRSP. Material y métodos: El análisis bacteriológico se realizó en muestras del sistema de purificación de agua, diluyentes de semen, semen crudo y almacenado, bancos de laboratorio y otras superficies de trabajo. Resultados: El crecimiento de una población bacteriana mixta se observó en muestras de agua de todas las CRSP excepto una. Aproximadamente el 85% de la CRSP tenía contaminación significativa en sus superficies de trabajo con al menos un contaminante bacteriano. Un total de 86% de muestras de semen crudo fueron contaminadas con una o más bacterias diferentes, mientras que el 100% de CRSP proporcionaron muestras contaminadas. La susceptibilidad bacteriana a agentes antimicrobianos varió en más del 80% para gentamicina, neomicina y ceftiofur a 40% o menos para penicilina y lincomicina. Conclusiones: La identificación de los puntos críticos proporciona el apoyo necesario para idear mejores estrategias para minimizar la contaminación en CRSP. Además, la evaluación del nivel de resistencia a los antimicrobianos ofrece información precisa para formular protocolos antibacterianos más eficientes que tengan en cuenta el uso racional de los antibióticos.

O objetivo do trabalho foi avaliar o efeito da aplicação intra-mamária de curcumina em ovelhas com mastite subclínica e ovelhas saudáveis sobre produção de leite, qualidade do leite e saúde de ovelhas. Para isso foi realizado dois experimentos: Experimento I: 10 ovelhas com mastite subclínica crônica foram divididas em dois grupos de cinco ovelhas cada: a) controle, foi aplicado 3 mL de óleo mineral via intra-mamária; b) curcumina, aplicado 2 mg de curcumina diluída em óleo mineral via intra-mamária. Houve efeito do tratamento, isto é, ovelhas que receberam a aplicação de curcumina tiveram maior produção de leite. Houve o efeito do tratamento para percentagem de proteína no leite, assim como tendencia de efeito do tratamento para lactose e solidos totais; com destaque para menores níveis de proteína, lactose e sólidos não gordurosos nas ovelhas do grupo curcumina comparado ao controle. Verificamos uma interação entre tratamento versus dia para proteína no leite nos dias 7 e 14 após aplicação; menor no grupo curcumina. Efeito do dia foi verificado para contagem de eritrócitos e leucócitos, assim como a concentrações de hemoglobina em ambos os grupos. Para o experimento II usamos 80 ovelhas divididas em 4 grupos: controle, T2, T3 e T4 (2, 3 e 4 mg de curcumina diluída em óleo mineral via intra-mamaria, respectivamente). Efeito do dia foi observado para o grupo T2, isto é, houve um aumento na produção de leite do dia 1 para 20. A contagem de células somáticas (CCS) sofreu efeito do tratamento, dia e interação entre tratamento versus dia. O maior CCS foi observado no grupo T4. Do grupo de ovelhas, 17 tiveram problemas na glândula mamaria após a aplicação dos quatro tratamentos, sendo que cinco ovelhas desenvolveram uma grave mastite ambiental e morreram; e os demais animais também testaram positivos para mastite subclínica no teste da raquete (Califórnia Mastite Teste). De modo geral, o uso da curcumina via intra-mamaria nas doses testadas não tem efeito curativo, assim como quando usado em ovelhas saudáveis causa efeito negativo, afetando a qualidade do leite (elevou CCS). Além disso, a aplicação de produtos intra-mamários (óleo mineral ou óleo + curcumina) são um risco elevado para o animal; portanto, não recomendamos.

The objective of this study was to characterize the vaginal bacterial flora and their antibiotic susceptibility in vitro after, application, and the reuse of an intravaginal progesterone device (CIDR) in controlling the estrous cycle in sheep. Thirty Texel ewe lambs were used, after carefully assessed on their health and body condition. Experimental groups were formed by new CIDR (CIDRn, n = 15) and CIDR reused (CIDRu, n = 15). Treatment with progesterone lasted 6 days. Sterile swabs were used for vaginal sample collection, a procedure performed previously of CIDR insertion and on the moment of CIDR removing. The predominant flora prior to insertion of intravaginal devices proved to be 93.3% (14/15) and 80.0% (12/15) of gram-positive agents, especially of the genera Bacillus sp. and Staphylococcus sp. in CIDRn CIDRu groups, respectively. Upon removal of the devices, however, it was observed that the emergence of gram-negative agents in 100% of the samples CIDRn, most of them belonging to the Enterobacteriaceae genus. In CIDRu group, there was a balance between negative- and gram-positive agents on the removal of the devices. Regarding to susceptibility, our findings revelated some degree of resistance in all samples. Therefore, our conclusions pointed out that intravaginal devices (CIDR), when employed in the first use, or reuse, for a period of 6 days, promote a change in vaginal flora of sheep, highlighting the predominance of gram-negative agents during its removal.

Laser beak trimming is a promising alternative to conventional hot-blade beak trimming as it is less painful and provides better beak uniformity and better animal welfare. In this study, laser vs. hot-blade beak trimming were compared in 400 Hy-line Brown pullets between 2-16 weeks of age. At 7 days of age, birds were distributed according to a completely randomized design into two treatments, with 10 replicates (pens) of 20 birds each. Birds and feed offer and residues were weekly weighed to determine weight gain, feed intake, and feed conversion ratio. In weeks 4, 8, 12, and 16 weeks, one bird per experimental unit was sacrificed to measure the development of the heart development, liver, proventriculus, gizzard, small intestine, and bursa. And of the oviduct in week 16. Pullers submitted to laser beak trimming presented higher weight gain and weekly feed intake, and better feed conversion ratio during the evaluated period. There was no influence of beak trimming methods on the development of the digestive organs, bursa or oviduct. Laser beak trimming can be used as an alternative to hot-blade beak trimming of commercial brown layers.

Background : Bovine leukemia virus (VLB) is an oncogenic deltaretrovirus associated with the development of persistent lymphocytosis (LP) and lymphosarcomas in cattle. LP is characterized by chronic elevation of the number of circulating lymphocytes, in the case of B lymphocytes. Several studies have described functional changes in various leukocyte populations in both blood and milk in VLB-infected animals. The impact of some chronic diseases of low lethality is aggravated by the emergence of comorbidities.The objective of the present study was to evaluate the oxidative metabolism and neutrophil phagocytosis of bovines of the Holtein breed naturally infected with the bovine leukemia virus (VLB). Materials, Methods & Results : In this study, 20 cows were divided into three groups: (NG) seven non-seroreagent animals for VLB and without hematological alterations; (GAL) eight seroreagent animals for VLB and without hematological alterations; and (GLP) five seroreagent animals for VLB with persistent lymphocytosis (LP). The oxidative metabolism of neutrophils was determined by the tetrazolium nitroblast reduction test stimulated or not with Zymosan particles. The percentage of neutrophils that phagocytosed Zymosan particle (s) was also evaluated. The data were initially evaluated for normality and homoscedasticity by the Shapiro-Wilk test. Then the ANOVA test followed by the Student-Newman-Keuls test was applied for the comparison between the NG, GAL and GLP animals. Comparison between the NG animals and the seroreagent animals for the VLB (GVLB) was also performed through the unpaired Student's t - test . The value of P < 0.05 was considered significant. No significant differences were observed in oxidative neutrophil metabolism in stimulated and non-stimulated samples with Zymosan particles nor in the percentage of neutrophils that phagocytosed Zymosan particle (s) among the three experimental groups. However, as no differences were observed between the seroreagent animals for VLB with and without LP, we chose to divide the animals into only two experimental, non-seroreagent and seroreagent groups for VLB. Thus, when non-seroreagent animals for the VLB were compared with the seroreagent animals for the VLB, which corresponds to the GAL and GLP animals, a significant difference was observed in relation to the oxidative metabolism by neutrophils stimulated with Zymosan particles. Discussion : Some viral diseases are often associated with increased susceptibility to new infections and several studies have evaluated the role of peripheral blood mononuclear cells in VLB infection, but few studies have investigated neutrophil function. Some authors, when evaluating phagocytic capacity and oxidative metabolism, respectively, of blood leukocytes from VLB-infected animals, observed that VLB-infected animals displaying LP had lower phagocytic capacity and lower production of Reactive Oxygen Species (ROS). Some studies have shown that oxygen consumption by neutrophils was higher in experimentally infected sheep by VLB after 15 weeks of challenge, but this species is not a natural host of the virus, since transmission does not occur between sheep and cattle and the pathogenesis of infection by VLB is more acute in sheep, a result of the lower latency period for LP development. Other authors, when evaluating the interference of VLB in milk leukocytes, concluded that VLB-infected animals show lower intensity of intracellular ROS production by flow cytometry in VLB-infected animals, especially animals expressing LP, despite the fact that percentage of milk neutrophils that produced ROS did not differ between groups. It can be concluded that VLB interferes in neutrophilic function with possible implications for the health of VLB-infected animals and may favor secondary infections.

The aim of this study was to evaluate the antimicrobial potential of the aqueous extract of green propolis in vitro against mastitis-causing and in vivo bacteria, evaluating the efficacy of treatment in Lacaune sheep. In the in vitro test, the minimum inhibitory concentration (MIC) was used; first, the MIC was obtained from the aqueous extract of green propolis for the strain of Staphylococcus. aureus ATCC 25523, defined as 1 mg/ml. For bacterial agents isolated from sheep with mastitis (Staphylococcus epidermidis, Staphylococcus intermedius, Staphylococcus hyicus, Corynebacterium spp. and Acinetobacter spp.), The concentration of 10 mg/ml was determined, while for Streptococcus equinus, Escherichia coli, and hemolytic E. coli, also isolated from sheep with mastitis, the concentration capable of reducing bacterial growth was 100 mg/ml. In the in vivo test, ten sheep were used, distributed in two treatments, five in the control group (CG) that received 2.5 ml of saline (vehicle), and five in the treated group (GT) that received 2.5 ml of aqueous (saline) propolis extract by the mammary route. The propolis dose tested (0.1 g/ml) was not effective for the treatment of mastitis, because the sheep remained positive in the racket test (CMT). The main microorganism isolated in the cases of mastitis in this study was Staphylococcus epidermidis. These results are preliminary; however, at the tested dose, the aqueous extract of green propolis delivered by the mammary route had no curative effect of mastitis. El objetivo de este estudio fue evaluar el potencial antimicrobiano del extracto acuoso de propóleos verdes in vitro contra las bacterias causantes de la mastitis e in vivo, evaluando la eficacia del tratamiento en ovejas lacaune. En la prueba in vitro, se utilizó una concentración mínima de inhibición (CIM); en primer lugar, CIM se obtuvo del extracto acuoso de propóleo verde para la cepa Staphylococcus aureus ATCC 25523, definida como 1 mg/ml. Para agentes bacterianos aislados de ovejas con mastitis (Staphylococcus epidermidis, Staphylococcus intermedius, Staphylococcus hyicus, Corynebacterium spp. y Acinetobacter spp.) se determinó la concentración de 10 mg/ml, mientras que para Streptococcus equinus, Escherichia coli y E coli Hemolitica. En la prueba in vivo, se utilizaron diez ovejas, distribuidas en dos tratamientos, cinco en el grupo de control (CG) que recibieron 2,5 ml de solución salina (vehículo), y cinco en el grupo tratado (TG) que recibieron 2,5 ml de extracto acuoso de propóleo (salina) vía intramamaria. La dosis de propóleos probada (0,1 g/ml) no fue eficaz para el tratamiento de la mastitis, ya que las ovejas siguieron siendo positivas en la prueba de ráquetica (CMT). El principal microorganismo aislado en casos de mastitis en este estudio fue Staphylococcus epidermidis. Estos resultados son preliminares; sin embargo, a la dosis probada, el extracto acuoso de propóleos verdes a través de intramamária no tuvo ningún efecto curativo. O objetivo deste estudo foi avaliar o potencial antimicrobiano do extrato aquoso de própolis verde in vitro contra bactérias causadoras de mastite e in vivo, avaliando a eficácia do tratamento em ovinos da raça Lacaune. No teste in vitro, utilizou-se concentração inibitória mínima (CIM); primeiro, a CIM foi obtida a partir do extrato aquoso de própolis verde para a cepa de Staphylococcus aureus ATCC 25523, definido como 1 mg/ml. Para agentes bacterianos isolados de ovelhas com mastite (Staphylococcus epidermidis, Staphylococcus intermedius, Staphylococcus hyicus, Corynebacterium spp. e Acinetobacter spp.) a concentração de 10 mg/ml foi determinada, enquanto para Streptococcus equinus, Escherichia coli e E. coli hemolítica a concentração capaz de reduzir o crescimento bacteriano foi de 100 mg/ml. No teste in vivo, foram utilizados dez ovinos, distribuídos em dois tratamentos, cinco no grupo controle (CG) que receberam 2,5 ml de soro fisiológico (veículo), e cinco no grupo tratado (GT) que receberam 2,5 ml de extrato aquoso de própolis (salina) via intramamária. A dose de própolis testada (0,1 g/ml) não foi eficaz para o tratamento da mastite, pois as ovelhas permaneceram positivas no teste de raquete (CMT). O principal microrganismo isolado nos casos de mastite neste estudo foi o Staphylococcus epidermidis. Estes resultados são preliminares; no entanto, na dose testada, o extrato aquoso de própolis verde via intramamária não teve efeito curativo.

Modern swine production employs a high degree of technology and is organized in various production stages, in which reproduction is one of the most significant. However, reproductive losses associated to fetal death are still high. Fetal losses, including fetal mummification, may occur at a rate below 1.5% in a sound herd. The causes of fetal death can be very diverse, and include various infectious agents. Therefore, investigating the causes of fetal losses is important in the decision-making process related to the control and prophylaxis of the herd. The goal of this study was to carry out a molecular survey, analyzing porcine circovirus 2 (PCV2), porcine parvovirus (PPV), and pathogenic Leptospira as potential agents related to fetal death in swine farms in Southern Brazil. We collected samples from three farms with a mummified index ≥ 2.5%. Fragments of brain, lung, kidney, liver, and heart were sampled for PCR analysis. Out of 100 samples examined, 87, 68, and 22 were positive for PCV2, PPV, and Leptospira spp., respectively. Moreover, we also identified coinfections with two and three pathogens in the same sample. Our findings contribute to the spreading of scientific knowledge related to infectious causes (PPV, PCV2, and pathogenic leptospires) of fetal losses in swine, as evidenced by the high frequencies of the investigated agents. RESUMO: A produção moderna de suínos emprega um alto grau de tecnologia e é organizada em várias etapas de produção, nas quais a reprodução é uma das mais importantes. No entanto, as perdas reprodutivas associadas à morte fetal ainda são altas. Perdas fetais, incluindo mumificação, podem ocorrer em taxa abaixo de 1,5% em rebanhos sadios. As causas da morte fetal podem ser diversas, incluindo causas infecciosas. Portanto, a investigação de causas relacionadas à ocorrência de perdas fetais é importante no processo relacionado ao controle e profilaxia do rebanho. O objetivo deste estudo foi realizar um levantamento molecular, incluindo circovírus suíno 2 (PCV2), parvovírus suíno (PPV), e leptospiras patogênicas como potenciais agentes relacionados à morte fetal em suínos no sul do Brasil. Foram coletadas amostras de três granjas com índice de fetos mumificados ≥ 2,5%. Fragmentos de cérebro, pulmão, rim, fígado e coração foram amostrados para análise por PCR. Das 100 amostras examinadas, 87 foram positivas para PCV2, 68 foram positivas para PPV e 22 foram positivas para Leptospira spp. Além disso, também identificamos co-infecções com dois e três patógenos em uma mesma amostra. Os resultados encontrados contribuem para a disseminação do conhecimento científico relacionado às causas infecciosas (PCV2, PPV e Leptospiras patogênicas) relacionadas às perdas fetais em suínos, assim como evidenciam a alta frequência dos agentes pesquisados.

Mastitis is a major disease affecting dairy sheep. It is caused by microorganisms that generate inflammation of the mammary gland in response to tissue invasion. This syndrome affects the welfare of ewes, as well as the production and quality of the milk, thereby reducing its productive efficiency. Because mastitis causes inflammation process, it also increases the production of free radicals that cause lesions via lipoperoxidation, causing damage to proteins, cells and tissues. One way to minimize the impact of the disease is antimicrobial treatment. Nevertheless, the continuous use of antimicrobials contributes to microbial resistance, in addition to producing residues in the milk and derivatives if not given during the grace period. Therefore, the objective of this study was to evaluate the consequences of subclinical mastitis on ewe health, milk production, milk composition and quality. We also evaluated the susceptibility of the bacteria in vitro using disk diffusion antibiograms. Finally, we performed two-way testing of efficacy of treatment in Lacaune ewes using the same agents. In the first stage of the study, 30 lactating ewes (±90 days) were used, 10 of which were negative on the CMT (California Mastitis Test) used as control group (CG) and 20 sheep with subclinical mastitis diagnosed by CMT (MG). Samples were collected and several analyses were performed on the milk and blood. We found that ewes in the MG had higher lipid peroxidation in serum and milk, as well as lower production, with reduction of the total dry extract in milk. There were 15 isolates of Staphylococcus hyicus, four isolates of each S. epidermidis and S. intermedius, and two isolates of Corynebacterium spp. The primary hematological result was leukocytosis in ewes with mastitis. Based on the antibiogram, we chose ceftiofur for in vivo tests. In this stage, we divided the sheep with subclinical mastitis into two subgroups of 10 ewes each, to receive drug by two routes: intramuscular (IM) and intramammary (IMM). In the IMM group, of the 10 CMT-positive ewes at the beginning of the experiment, seven were already negative by the racket test 120 h after the last application (70% efficacy). In the IM group, of the 10 positive ewes, only four were negative after 120 h of the final application, a low efficacy treatment (40%). We evaluated antimicrobial residues in the milk of treated animals. We found this material within 5 days after treatment in the two forms used; despite the fact that the product's stated withholding period is 3 days. We conclude that ewes with mastitis produce less milk of lower quality. We also conclude that, although ceftiofur is 100% effective in vitro, when used in ewes with mastitis, the efficacy did not exceed 70%, and was more efficient when administered via the intramammary route.

Rhodococcus equi é um micro-organismo intracelular facultativo, agente etiológico da rodococose, uma importante enfermidade que acomete principalmente potros com menos de seis meses de idade, causando a morte geralmente em decorrência de lesões pulmonares. Este agente também tem potencial zoonótico e emergiu como um patógeno oportunista no mundo, acometendo humanos imunocomprometidos, especialmente os transplantados e infectados pelo vírus da imunodeficiência humana (HIV). Entretanto, infecções por R. equi em hospedeiros hígidos tem sido relatadas, principalmente em crianças e idosos. Estudos tem mostrado um nível crescente na resistência de isolados de R. equi em relação aos antimicrobianos comumente utilizados no tratamento de animais e seres humanos infectados por este agente. A virulência deste pode estar associada a fatores como a cápsula de polissacarídeo, fosfolipase C e à enzima colesterol oxidase (fator equi). No entanto, uma proteína localizada em um plasmídeo, designada vapA, é essencial para a sobrevivência e replicação do agente em macrófagos. Com isso, os objetivos deste estudo foram avaliar o perfil de suscetibilidade de isolados de R. equi de diferentes fontes em relação aos antimicrobianos mais comumente utilizados na terapêutica animal e humana, bem como verificar a associação entre a presença do gene vapA e o índice de resistência múltipla aos antimicrobianos (IRMA). Neste estudo, 67 isolados brasileiros de R. qui de diferentes fontes foram analisados: 30 provenientes de amostras clínicas de equinos, sete de humanos e 30 ambientais (seis do solo e 24 de fezes de equinos). Para avaliar o perfil de suscetibilidade dos isolados utilizou-se o método de disco difusão, sendo testadas 16 drogas de diferentes classes de antimicrobianos. As amostras clínicas de equinos apresentaram as maiores taxas de resistência à penicilina (86,7%) e lincomicina (30%). Além disso, foram também resistentes a macrolídeos (azitromicina a 6,7%, eritromicina a 6% e claritromicina a 3,3%) e rifamicina (13%). Todas as amostras humanas e ambientais foram sensíveis aos macrolídeos e rifamicina. Contudo, isolados ambientais demonstraram níveis elevados de resistência à penicilina e cloranfenicol. Da mesma forma, os isolados humanos apresentaram alto nível de resistência ao ceftiofur, lincomicina e sulfazotrim. O IRMA em todos os isolados de R. equi variou de 0 a 0,67, tendo como valores médios 0,19 para as amostras clínicas de equinos, 0,14 nas ambientais e em isolados humanos foi de 0,1. Apesar da alta sensibilidade observada nos isolados analisados, verificaram-se diferentes níveis de resistência nas amostras clínicas de equinos. Em contraste, os isolados ambientais não demonstraram resistência em relação aos agentes antimicrobianos utilizados na terapia da rodococose equina. Além disso, em isolados humanos não se observou resistência contra a droga para uso restrito em terapia de humano. Com base no IRMA observado em isolados clínicos de equinos, destacamos a importância de medidas restritivas e mais cautela na utilização de antimicrobianos em infecções causadas por R. equi para evitar o aumento de novas cepas multirresistentes. Rhodococcus equi is a facultative intracellular bacterium and etiological agent of rodococosis, an important disease that affects specially foals under six months old and leading the death generally due to pulmonary lesions. R. equi also has zoonotic potential, and it has emerged as an opportunistic pathogen in the world, specially infecting solid organ transplant recipients and immunocompromised human patients, mainly those infected by human immunodeficiency virus (HIV). Additionally, R. equi infections by healthy hosts have been reported principally in children and elderly individuals. Studies have shown an increasing level of resistance of isolates of R. equi against antibiotics commonly used to treat affected animals and humans. The virulence of this agent is associated with a protein located on a plasmid, designated vapA, it is essential for survival and replication of R. equi within macrophages. The present study evaluated the susceptibility profile of R.equi isolates from different sources against the antimicrobials most commonly used to treat animals and humans, as well as the occurrence and association of vapA gene and the antimicrobial multiple resistance index (AMRI). Sixty-seven Brazilian isolates of R. equi from different sources were analyzed: 30 clinical samples of horses, seven of human and 30 of environmental (six from soil and 24 from horse feces). To evaluate the susceptibility profile of R. equi isolates, the Kirby Bauer method was performed by using 16 drugs of 11 distinct antimicrobials classes. Additionally, those samples were also resistant to macrolides (azithromycin 6.7%, erythromycin 6% and clarithromycin 3.3%) as well as rifamycin (13%). All human and environmental samples were sensitive to macrolides and rifamycin. However, environmental isolates demonstrated high levels of resistance to penicillin and chloramphenicol. Similarly, human isolates had high level of resistance to ceftiofur, lincomycin and sulfazotrim. AMRI in all R. equi isolates ranged 0 to 0.67, in clinical samples of horses the AMRI mean value obtained was 0.19, in environmental was 0.14 and in human isolates was 0.1. Despite of high sensitivity observed in most Brazilian R. equi isolates analyzed, it was verified in clinical samples of horses different levels of resistance against all antibiotics commonly used in the treatment of rodococosis. In contrast, environmental isolates not demonstrated any resistance against antimicrobials employed in equine rodococosis therapy. In addition, in human isolates it was not observed resistance against drugs for restricted use in human rodococosis therapy. Based on the AMRI achieved in clinical horse isolates, we highlight the importance of restrictive measures and more caution to use antimicrobial drugs in R. equi infections to avoid increasing of new multidrug-resistant strains.

O presente trabalho teve como objetivos determinar o perfil de sensibilidade aos antimicrobianos e avaliar a presenca de mecanismos de resistencia antimicrobiana em Staphylococcus spp. ( n =36) isolados de mastite em ovelhas do municipio de Chapeco-SC. O potencial para producao de biofilme foi determinado pelos testes fenotipicos de Agar Vermelho Congo, DAPI e Violeta de Genciana e por teste molecular pela tecnica de PCR para a deteccao do gene ica D. Para determinar o perfil de resistencia aos antimicrobianos, foi realizado o teste de difusao em disco e deteccao dos genes de resistencia bla Z, mec A, erm (A, B e C) e msr A. O teste da bomba de efuxo foi realizado atraves do crescimento das culturas em Agar Muller Hinton contendo brometo de etidio. Os resultados mostraram que 1 (2,78%), 36 (100%) e 10 (27,78%) isolados foram considerados produtores de biofilme pelos testes de Agar Vermelho Congo, DAPI e Violeta de Genciana, respectivamente, enquanto que o gene ica D foi observado em apenas 2 (5,55%) isolados. O menor percentual de sensibilidade foi observado para ampicilina (58,33%) e penicilina (58,33%). Os isolados avaliados foram positivos para os genes de resistencia bla Z (58,33%) e msr A (11,11%). Nenhum isolado apresentou os genes de resistencia erm (A, B, C) e apenas uma amostra foi positiva para o teste da bomba de efluxo.

This study aimed to determine the antimicrobial susceptibility profile and to assess the presence of mechanisms of antimicrobial resistance in Staphylococcus spp. (n=36) isolated from mastitis in sheep’s Chapecó-SC. The potential for biofilm production was determined by phenotypic tests of Congo Red Agar, DAPI and Gentian Violet and by PCR for the detection of icaD gene. To evaluate the antimicrobial resistance testing was performed disk diffusion and detection of resistance genes blaZ, mecA, ermA, ermB and ermC and msrA also performed by PCR.The pump test was conducted by efuxo crop growth Muller Hinton agar containing ethidium bromide. The results showed that 1 (2,78%), 36 (100%) and 10 (27,78%) isolates were considered to produce a biofilm on Congo Red Agar test, Gentian Violet and DAPI, respectively, while the gene icaD was observed in only 2 (5.55%) isolates. The lowest percentage of sensitivity was observed for ampicillin (58.33%) and penicillin (58.33%). All strains tested were negative for the mecA, ermA, ermB and ermC genes. However, the isolates were positive for other resistance genes, being the blaZ and the msrA, with percentages of positivity of 58.33% and 11.11% respectively. Only one sample was positive for efflux pump test.O presente trabalho teve como objetivos determinar o perfil de sensibilidade aos antimicrobianos e avaliar a presença de mecanismos de resistência antimicrobiana em Staphylococcus spp. (n=36) isolados de mastite em ovelhas do município de Chapecó-SC. O potencial para produção de biofilme foi determinado pelos testes fenotípicos de Agar Vermelho Congo, DAPI e Violeta de Genciana e por teste molecular pela técnica de PCR para a detecção do gene icaD. Para determinar o perfil de resistência aos antimicrobianos, foi realizado o teste de difusão em disco e detecção dos genes de resistência blaZ, mecA, erm (A, B e C) e msrA. O teste da bomba de efuxo foi realizado através do crescimento das culturas em Agar Muller Hinton contendo brometo de etídio. Os resultados mostraram que 1 (2,78%), 36 (100%) e 10 (27,78%) isolados foram considerados produtores de biofilme pelos testes de Agar Vermelho Congo, DAPI e Violeta de Genciana, respectivamente, enquanto que o gene icaD foi observado em apenas 2 (5,55%) isolados. O menor percentual de sensibilidade foi observado para ampicilina (58,33%) e penicilina (58,33%). Os isolados avaliados foram positivos para os genes de resistência blaZ (58,33%) e msrA (11,11%). Nenhum isolado apresentou os genes de resistência erm (A, B, C) e apenas uma amostra foi positiva para o teste da bomba de efluxo.

In intensive dairy farming, persistent intramammary infection has been associated with specific Staphylococcus (S.) aureus strains, and these strains may be resistant to antimicrobials. The objective of this study was to evaluate the antimicrobial resistance phenotypes of S. aureus isolates and to assess the distribution and the persistence of clonal groups in small dairy herds of southern Brazil. Milk samples were collected from all lactating cows from 21 dairy farms over a two-year period, totaling 1,060 samples. S. aureus isolates were tested for susceptibility to thirteen antimicrobials using the disk diffusion method. The total DNA of the isolates was subjected to SmaI digestion followed by pulsed-field gel electrophoresis (PFGE). Banding patterns differing by ≤4 bands were considered members of a single PFGE cluster. The frequency of S. aureus isolation ranged from 3.45% to 70.59% among the 17 S. aureus-positive herds. Most S. aureus isolates (87.1%) were susceptible to all antimicrobials; resistance to penicillin (18.2%) was the most frequently observed. The 122 isolates subjected to macrorestriction analysis were classified into 30 PFGE-clusters. Among them, only 10 clusters were intermittent or persistent over the two-year period. The majority (93.6%) of isolates belonging to persistent and intermittent clusters were susceptible to all tested antimicrobials. S. aureus intramammary colonization in small dairy farms of southern Brazil is most frequently caused by sporadic PFGE clusters, although some persistent clusters can arise over time. Both sporadic and persistent isolates were highly susceptible to antimicrobials. RESUMO: A infecção intramamária persistente em bovinos leiteiros tem sido associada com estirpes de Staphylococcus (S.) aureus específicos, os quais podem ser resistentes a antimicrobianos. Os objetivos deste estudo foram avaliar os fenótipos de resistência aos antimicrobianos de isolados de S. aureus e a distribuição e persistência de grupos clonais em pequenos rebanhos leiteiros do sul do Brasil. As amostras de leite foram coletadas de todas as vacas em lactação de 21 propriedades leiteiras, ao longo de um período de dois anos, perfazendo um total de 1.060 amostras. Isolados de S. aureus foram testados quanto à resistência frente a treze antimicrobianos, pelo método de disco-difusão. O DNA total dos isolados foi clivado com a enzima Smal e submetido a eletroforese em gel de campo pulsado (PFGE). Padrões de bandas diferentes por ≤4 bandas foram considerados como pertencentes ao mesmo grupo clonal. A freqüência de S. aureus variou de 3,45% até 70,59%, entre os 17 rebanhos com isolamento positivo de S. aureus. A maioria dos isolados de S. aureus (87,1%) foi suscetível a todos os antimicrobianos; resistência à penicilina (18,2%) foi a mais freqüentemente observada. Os 122 isolados submetidos à análise de macrorestrição foram classificados em 30 grupos clonais de PFGE. Entre eles, apenas dez grupos clonais foram intermitentes ou persistentes ao longo do período de dois anos. A maioria (93,6%) dos isolados pertencentes a grupos clonais persistentes e intermitentes foram suscetíveis a todos os antimicrobianos testados. Concluiu-se que a colonização intramamária em bovinos de pequenas propriedades leiteiras do Sul do Brasil é mais frequentemente causada por grupos clonais esporádicos de S. aureus, embora alguns grupos clonais persistentes possam ocorrer ao longo do tempo. Em ambos os grupos clonais os isolados foram majoritariamente suscetíveis a antimicrobianos.

The current study evaluated the presence of virulence factors by a multiplex PCR technique and then phylogenetically classified the studied strains into groups A, B1, B2 and D, according to Clermont et al. (2000), in 152 intestinal and extraintestinal swine isolates of Escherichia coli. Seventy seven isolates tested were positive for virulence factors. Phylogenetic characterization placed 21 samples into group A, 65 into B1, 19 into B2 and 47 into D. Fourteen urine samples were classified as uropathogenic E. coli (UPEC), nine were both UPEC and enterotoxigenic E. coli (ETEC) and four were ETEC only. The most common phylogenetic classifications were B1 and D groups. Of the analyzed fecal samples, 25 were classified as ETEC. Phylogenetically, the group of higher occurrence was B1, followed by B2, A and D. For the small intestine samples, 20 were classified as ETEC. Phylogenetic analysis found groups B1 and A to be the most commons in these samples. Six isolated tissue samples were classified as ETEC and most of them were designated as group D by phylogenetic classification. The phylogenetic analysis could be employed in veterinary laboratories in the E. coli isolates screening, including the possibility of vaccine strain selection and epidemiological searches. O presente estudo teve por objetivo avaliar a presença de diferentes fatores de virulência em 152 isolados de Escherichia coli intestinais e extra-intestinais provenientes de suínos pela técnica de PCR multiplex e classificá-los nos grupos filogenéticos A, B1, B2 e D, de acordo com Clermont et al. (2000). Setenta e sete isolados foram positivos para pelo menos um fator de virulência. Através da caracterização filogenética, 21 isolados foram caracterizados como pertencentes ao grupo A, 65 ao grupo B1, 19 ao grupo B2 e 47 isolados ao grupo D. Quatorze isolados de urina foram caracterizados como E. coli uropatogênica (UPEC); nove apresentaram fatores de UPEC e E. coli enterotoxigênica (ETEC) simultaneamente e quatro foram classificados como ETEC. Na classificação filogenética, os isolados provenientes de amostras de urina classificaram-se principalmente nos grupos D e B1. Das amostras de fezes analisadas, 25 demonstraram fatores de virulência característicos do patotipo ETEC. Filogeneticamente, o grupo de maior ocorrência foi o B1 seguido de B2, A e D. Em relação às cepas isoladas de intestino delgado, 20 foram caracterizadas como ETEC. Pela filogenia, 23 isolados classificaram-se nos grupos A ou B1. Seis isolados de tecidos foram qualificados como ETEC e a maioria deles foram designados como pertencentes ao grupo D, pela classificação filogenética. A análise filogenética pode ser empregada em laboratórios de diagnóstico veterinário como um screening para isolados de E. coli, incluindo a possibilidade de seleção de cepas vacinais e levantamentos epidemiológicos.