In vivo selection of resistant E. coli after ingestion of milk with added drug residues.

Antimicrobial resistance represents a major global threat to modern medicine. In vitro studies have shown that very low concentrations of drugs, as frequently identified in the environment, and in foods and water for human and animal consumption, can select for resistant bacteria. However, limited information is currently available on the in vivo impact of ingested drug residues. The objective of our study was to evaluate the effect of feeding preweaned calves milk containing antimicrobial drug residues (below the minimum inhibitory concentration), similar to concentrations detected in milk commonly fed to dairy calves, on selection of resistant fecal E. coli in calves from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR), and 15 calves were fed raw milk with drug residues (DR) by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 µg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth prior to the first feeding in the trial (pre-treatment) until 6 weeks of age. A significantly greater proportion of E. coli resistant to ampicillin, cefoxitin, ceftiofur, streptomycin and tetracycline was observed in DR calves when compared to NR calves. Additionally, isolates from DR calves had a significant decrease in susceptibility to ceftriaxone and ceftiofur when compared to isolates from NR calves. A greater proportion of E. coli isolates from calves in the DR group were resistant to 3 or more antimicrobial drugs when compared to calves in the ND group. These findings highlight the role that low concentrations of antimicrobial drugs have on the evolution and selection of resistance to multiple antimicrobial drugs in vivo

Ingestion of Milk Containing Very Low Concentration of Antimicrobials: Longitudinal Effect on Fecal Microbiota Composition in Preweaned Calves.

Although antimicrobial drugs are central to combat disease in modern medicine, the use of these drugs can have undesired consequences for human and animal health. One consequence is the post-therapy excretion of pharmacological agents, such as the elimination of drug residues at very low concentrations in the milk of lactating mammals. Limited information is currently available on the impact from the exposure of the gut microbiota to drug residues using in vivo natural models. The objective of our study was to address this knowledge gap and evaluate the effect on the fecal microbiota composition from feeding preweaned dairy calves raw milk with residual concentrations of ampicillin, ceftiofur, penicillin, and oxytetracycline from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR), and 15 calves were fed raw milk with drug residues (DR) by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 μg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth, prior to the first feeding in the trial (pre-treatment), until 6 weeks of age. Sequencing of the microbial 16S rRNA genes was conducted using the Illumina MiSeq, which provides a high resolution of the microbiota down to the genus level. Discriminant analysis showed that, except for pre-treatment samples, calves fed milk with drug residues and calves fed milk without drug residues easily discriminated at the genus level on their weekly microbial profile. However, analysis comparing the abundance of taxon between NR and DR showed significant differences only at the genus levels, and not at the phylum, class, order or family levels. These results suggest that although drug residues can result in clear discriminate gut microbial communities, they do not result in disruption of taxonomic levels above the genus

A medida da amplitude da distribuição do tamanho dos eritrócitos está associada ao risco cardiovascular em adultos

Estudos recentes têm mostrado que o RDW (do inglês Red Cell Distribution Width) é um marcador preditivo e prognóstico de mortalidade e eventos cardiovasculares (DCV) na população geral e em pacientes com DCV. Este estudo teve como objetivo investigar a associação entre RDW e risco de DCV em uma grande amostra de adultos. Foram incluídas uma subamostra de participantes sem DCV da coorte ELSA-Brasil (n=4.481). Na abordagem transversal, a análise de regressão múltipla foi usada para investigar a associação entre o RDW e o Escore de Risco de Framingham (ERF). O modelo linear de efeito misto foi usado para avaliar se o RDW basal previa mudanças no risco de DCV após cerca de quatro anos de acompanhamento. A análise transversal mostrou que o RDW foi independentemente associado ao ERF, os participantes no quarto quartil da distribuição do RDW tiveram um ERF 29% maior do que aqueles no primeiro quartil RDW (p<0,001). Na análise longitudinal, o RDW permaneceu associado ao aumento do ERF. Nesta grande coorte de adultos brasileiros, o RDW foi independentemente associado ao aumento do risco de DCV, medido pelo ERF, tanto no início quanto após quatro anos de acompanhamento. No entanto, RDW não previu mudança no risco de DCV neste seguimento de curto prazo.Red cell distribution width (RDW) is a measure of erythrocyte size variability. Recent studies have shown that RDW is a predictive, and prognostic marker of mortality and cardiovascular (CVD) events in the general population and in CVD patients. This study aimed to investigate the association between RDW and CVD risk in a large sample of adults. A subsample of CVD free participants of the ELSA-Brasil cohort were included (n=4,481). In the cross-sectional approach, multiple regression analysis was used to investigate the association between RDW and the Framingham Risk Score (FRS). Linear mixed effect model evaluated whether baseline RDW predicted changes in CVD risk after about fouryear follow up. Cross-sectional analysis showed that RDW was independently associated with FRS, participants in the fourth-quartile of RDW distribution had a 29% higher FRS than those in the first-quartile RDW (p<0.001). A longitudinal analysis revealed that RDW remained associated with increased FRS. In this large cohort of adult Brazilians, RDW was independently associated with increased CVD risk, as measured by the FRS, both at baseline and after four-year follow-up. However, RDW did not predict change in CVD risk in this short-term follow up

The Bos taurus maternal microbiome: Role in determining the progeny early-life upper respiratory tract microbiome and health.

Natural transference of maternal microbes to the neonate, especially at birth via the vaginal canal, has recently been recognized in humans and cows; however, its microbial influence on calf health has not yet been documented. We compared the bacterial communities in vaginal and fecal samples from 81 pregnant dairy cows versus those in nasopharyngeal and fecal samples collected at 3, 14 and 35 days of life from their respective progeny. The microbiota of the calf upper respiratory tract (URT), regardless of calf age, was found to be highly similar to the maternal vaginal microbiota. Calf fecal microbiota clustered closely to the maternal fecal microbiota, progressing toward an adult-like state over the first 35 days when relative abundances of taxa were considered. Sixty-four, 65 and 87% of the detected OTUs were shared between cow and calf fecal microbiota at days 3, 14 and 35 respectively, whereas 73, 76 and 87% were shared between maternal vaginal microbiome and calf URT microbiota at days 3, 14 and 35, respectively. Bacteroidetes, Ruminococcus, Clostridium, and Blautia were the top four genera identified in maternal and calf fecal samples. Mannheimia, Moraxella, Bacteroides, Streptococcus and Pseudomonas were the top five genera identified in maternal vaginal and calf URT samples. Mannheimia was relatively more abundant in the vaginal microbiota of cows whose progeny were diagnosed with respiratory and middle ear disease. Our results indicate that maternal vaginal microbiota potentially influences the initial bacterial colonization of the calf URT, and that might have an important impact on the health of the calf respiratory tract and middle ear

Bulletin de la Société nivernaise des lettres, sciences et arts

19951995 (VOL44,A1995)-1995.Appartient à l’ensemble documentaire : Bourgogn

Evaluation of milk sample fractions for characterization of milk microbiota from healthy and clinical mastitis cows - Fig 6

<p>Venn diagram showing the numbers of unique and shared bacterial families among <i>Streptococcus</i> spp.-mastitis milk samples according to milk sample fractions: fat, fat + pellet, pellet, and whole milk (WM) and DNA extraction kit (PS and PF) (B). Numbers at the top of the milk sample type name indicate the total number of families detected in the samples processed by that protocol. Mean relative abundance (MRA) of f__Streptococcaceae taxon in each milk sample fractions (C). Error bars represent the standard error of the mean.</p

Comparison of DNA and amplicon concentration among DNA extraction protocols using different milk sample fractions (whole milk, fat, fat + pellet, and pellet) according to milk-health status groups (healthy or mastitis caused by <i>Escherichia coli</i>, <i>Klebsiella</i> spp., <i>Streptococcus</i> spp., and all groups combined) and two different DNA extraction kits.

<p>Numbers in parentheses represent the standard error of the mean.</p