scholarly journals Relations between the consumption of antimicrobial growth promoters and the occurrence of resistance among Enterococcus faecium isolated from broilers

2004 ◽  
Vol 132 (1) ◽  
pp. 95-105 ◽  
Author(s):  
H.-D. EMBORG ◽  
J. S. ANDERSEN ◽  
A. M. SEYFARTH ◽  
H. C. WEGENER

The present study investigates, at farm level, the effect of the time-span between sampling and the last time a particular antimicrobial growth promoter (AGP) was included in the feed on the probability of selecting an AGP-resistant Enterococcus faecium isolate from a broiler flock. The probability that a randomly selected E. faecium isolate was resistant to avilamycin, erythromycin or virginiamycin was 0·91, 0·92 and 0·84, respectively if the isolate originated from a broiler flock fed either avilamycin- or virginiamycin-supplemented feed. As the time-span between sampling and the last AGP consumption increased, the probability of isolating an E. faecium isolate resistant to a particular AGP decreased (probability <0·2 within 3–5 years after last exposure to AGPs). The decrease in probability over time showed little farm-to-farm variation. The number of times a particular AGP was given to previous flocks reared in the same house had no effect on the probability of isolating a resistant isolate.

2009 ◽  
Vol 75 (22) ◽  
pp. 7125-7134 ◽  
Author(s):  
T. W. Alexander ◽  
T. Reuter ◽  
R. Sharma ◽  
L. J. Yanke ◽  
E. Topp ◽  
...  

ABSTRACT Model fecal deposits from cattle fed or not fed antimicrobial growth promoters were examined over 175 days in the field for growth and persistence of total Escherichia coli and numbers and proportions of ampicillin-resistant (Ampr) and tetracycline-resistant (Tetr) E. coli. In addition, genotypic diversity and the frequency of genetic determinants encoded by Ampr and Tetr E. coli were investigated. Cattle were fed diets containing chlortetracycline (44 ppm; A44 treatment group), chlortetracycline plus sulfamethazine (both at 44 ppm; AS700 treatment group), or no antibiotics (control). Fecal deposits were sampled 12 times over 175 days. Numbers of Tetr E. coli in A44 and AS700 deposits were higher (P < 0.001) than those of controls and represented up to 35.6% and 20.2% of total E. coli, respectively. A time-by-treatment interaction (P < 0.001) was observed for the numbers of Tetr and Ampr E. coli. Except for Ampr E. coli in control deposits, all E. coli numbers increased (P < 0.001) in deposits up to day 56. Even after 175 days, high Tetr E. coli numbers were detected in A44 and AS700 deposits [5.9 log10 CFU (g dry matter)− 1 and 5.4 log10 CFU (g dry matter)− 1, respectively]. E. coli genotypes, as determined by pulsed-field gel electrophoresis, were diverse and were influenced by the antimicrobial growth promoter and the sampling time. Of the determinants screened, bla TEM1, tetA, tetB, tetC, sul1, and sul2 were frequently detected. Occurrence of determinants was influenced by the feeding of antimicrobials. Fecal deposits remain a source of resistant E. coli even after a considerable period of environmental exposure.


2017 ◽  
Vol 3 (1) ◽  
pp. 103-108
Author(s):  
Md Sirazul Islam ◽  
M Mamnur Rashid ◽  
Mohammad Shamsul Arefin ◽  
Pronab Naha ◽  
Md Rokanuddula

A study was conducted to determine the efficacy of three most commonly used growth promoters from different pharmaceutical companies on growth performance of hybrid walking catfish (Clarias batrachus × Clarias gariepinus). The experiment was done in the wet laboratory of the Department of Aquaculture, BAU, Mymensingh, with a total of 10 aquaria and 160 fish having mean initial weight of 6.3 ± 0.48 g. The three growth promoters, “Charger gel” from Fishtech (BD) Ltd., “Growth gel” from Advance Agrotech (BD) Ltd. and “Hepaprotect-aqua” from Renata Animal health Ltd., were used in separate nine (9) aquaria at recommended, lower dose and higher dose respectively. One aquarium was used as control (diet without any growth promoter). The fish were fed with paragon nursery floating feed at 20% of body weight in each aquarium for 28 days. Doses of Charger gel were given as 80, 60 and 100 mg/20 g feed/day, that of Growth gel, 0.14, 0.12 and 0.16 ml/20 g feed/day and of Hepaprotect-aqua, 30, 15 and 50 mg/20 g feed/day. Re-circulatory system was used throughout the experimental period. By applying recommended, lower and higher dose of “Charger gel”, mean final weights were found as 23.0, 21.9 and 35.9 g; average daily weight gain as 0.60, 0.56 and 1.06 g and specific growth rate (SGR) as 2.01, 1.93 and 2.70% respectively. For “Growth gel”, mean final weights were found as 22.8, 17.3 and 31.1 g; average daily weight gain as 0.59, 0.39 and 0.88 g and SGR as 1.99, 1.57 and 2.48 % respectively. For “Hepaprotect-aqua”, mean final weights were found as 24.2, 17.5 and 28.2 g; average daily weight gain as 0.64, 0.40 and 0.78 g and SGR as 2.09, 1.58 and 2.32% respectively. In all the cases survival rates were 100%. All the three growth promoters showed better results at their higher doses in comparison to their results in lower and recommended doses. However, in average Charger gel showed the best result than the other two growth promoters. This information on the efficacy study of growth promoters needs to be disseminated to the farmers for improved fish production.Asian J. Med. Biol. Res. March 2017, 3(1): 103-108


Author(s):  
Cecilia G. Carvalhaes ◽  
Helio S. Sader ◽  
Jennifer M. Streit ◽  
Mariana Castanheira ◽  
Rodrigo E. Mendes

Oritavancin displayed potent and stable activity (MIC 90 range, 0.06-0.5 mg/L) over time (2010-2019) against Gram-positive pathogens causing bloodstream infections, including methicillin-resistant Staphylococcus aureus and resistant subsets of Enterococcus spp. Daptomycin and linezolid were also active against methicillin-resistant S. aureus and vancomycin-resistant Enterococcus . Only oritavancin and linezolid remained active against Enterococcus faecium isolates displaying an elevated daptomycin MIC (i.e., 2-4 mg/L). Proportions of methicillin-resistant S. aureus and vancomycin-resistant Enterococcus within the respective S. aureus and enterococcal populations decreased over this period.


2021 ◽  
Vol 8 ◽  
Author(s):  
Randal K. Buddington ◽  
Taisiya Yakimkova ◽  
Adebowale Adebiyi ◽  
Victor V. Chizhikov ◽  
Igor Y. Iskusnykh ◽  
...  

The goal of enteral nutritional support for infants born preterm or small for gestational age (SGA) is to achieve normal growth and development. Yet, this is difficult to achieve because of intestinal immaturity. Our objective was to determine if birth weight, protein intake, and the growth promoters leucine (10 g/L) or calcium-ß-hydroxy-ß-methylbutryate (HMB; 1.1 g/L) would affect trajectories of intestinal growth and functions and weights of other organs. Preterm pigs were delivered at gestational day 105 (91% of term) and fed for 6 or 7 days isocaloric formulas that differed in protein content (50 g or 100 g protein/L), with and without the growth promoters leucine or HMB. For comparative purposes organ weights were measured within 12 h after delivery for six term pigs of low and six of average birth weights. The responses of intestinal growth and total intestinal brush border membrane carbohydrases to protein level and supplemental leucine were of greater magnitude for preterm pigs of lower birth weight. Forskolin stimulated chloride secretion in the proximal small intestine was lower for pigs fed the low protein milk replacers. Capacities of the entire small intestine to transport glucose (mmol/kg-day) were not responsive to protein level, leucine, or HMB, and did not differ between small and large pigs. Relative organ weights of the small and average weight term pigs were similar, but some differed from those of the preterm pigs suggesting preterm birth and the standards of care used for this study altered the trajectories of development for the intestine and other organs. Although leucine is an effective generalized growth promoter that enhances gut development of small preterm pigs, it does not mitigate compromised neurodevelopment. Our findings using preterm pigs as a relevant preclinical model indicate nutrition support strategies can influence development of some gastrointestinal tract characteristics and the growth of other organs.


Author(s):  
Uga Sproģis ◽  
Matīss Rikters

We present the Latvian Twitter Eater Corpus - a set of tweets in the narrow domain related to food, drinks, eating and drinking. The corpus has been collected over time-span of over 8 years and includes over 2 million tweets entailed with additional useful data. We also separate two sub-corpora of question and answer tweets and sentiment annotated tweets. We analyse the contents of the corpus and demonstrate use-cases for the sub-corpora by training domain-specific question-answering and sentiment-analysis models using the data from the corpus.


2021 ◽  
Author(s):  
Sarah Mollerup ◽  
Christine Elmeskov ◽  
Heidi Gumpert ◽  
Mette Pinholt ◽  
Tobias Steen Sejersen ◽  
...  

AbstractBackgroundDaptomycin is a cyclic lipopeptide used in the treatment of vancomycin-resistant Enterococcus faecium (VREfm). However, the development of daptomycin-resistant VREfm challenges the treatment of nosocomial VREfm infections. Resistance mechanisms of daptomycin are not fully understood. Here we analysed the genomic changes leading to a daptomycin-susceptible VREfm isolate becoming resistant after 40 days of daptomycin and linezolid combination therapy.MethodsThe two isogenic VREfm isolates (daptomycin-susceptible and daptomycin-resistant) were analysed using whole genome sequencing with Illumina and Nanopore.ResultsWhole genome comparative analysis identified the loss of a 46.5 kb fragment and duplication of a 29.7 kb fragment in the daptomycin-resistant isolate, with many implicated genes involved in cell wall synthesis. Two plasmids of the daptomycin-susceptible isolate were also found integrated in the chromosome of the resistant isolate. One nonsynonymous SNP in the rpoC gene was identified in the daptomycin-resistant isolate.ConclusionsDaptomycin resistance developed through chromosomal rearrangements leading to altered cell wall structure. Such novel types of resistance mechanisms can only be identified by comparing closed genomes of isogenic isolates.


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