Monte Carlo Simulations Suggest Current Chlortetracycline Drug-Residue Based Withdrawal Periods Would Not Control Antimicrobial Resistance Dissemination from Feedlot to Slaughterhouse

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Casey L. Cazer

2017-09-01

Full Text Available Antimicrobial use in beef cattle can increase antimicrobial resistance prevalence in their enteric bacteria, including potential pathogens such as Escherichia coli. These bacteria can contaminate animal products at slaughterhouses and cause food-borne illness, which can be difficult to treat if it is due to antimicrobial resistant bacteria. One potential intervention to reduce the dissemination of resistant bacteria from feedlot to consumer is to impose a withdrawal period after antimicrobial use, similar to the current withdrawal period designed to prevent drug residues in edible animal meat. We investigated tetracycline resistance in generic E. coli in the bovine large intestine during and after antimicrobial treatment by building a mathematical model of oral chlortetracycline pharmacokinetics-pharmacodynamics and E. coli population dynamics. We tracked three E. coli subpopulations (susceptible, intermediate, and resistant during and after treatment with each of three United States chlortetracycline indications (liver abscess reduction, disease control, disease treatment. We compared the proportion of resistant E. coli before antimicrobial use to that at several time points after treatment and found a greater proportion of resistant enteric E. coli after the current withdrawal periods than prior to treatment. In order for the proportion of resistant E. coli in the median beef steer to return to the pre-treatment level, withdrawal periods of 15 days after liver abscess reduction dosing (70 mg daily, 31 days after disease control dosing (350 mg daily, and 36 days after disease treatment dosing (22 mg/kg bodyweight for 5 days are required in this model. These antimicrobial resistance withdrawal periods would be substantially longer than the current U.S. withdrawals of 0–2 days or Canadian withdrawals of 5–10 days. One published field study found similar time periods necessary to reduce the proportion of resistant E. coli following

Chlortetracycline and Oxytetracycline Residues in Poultry Tissues and Eggs

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Meredith, W. E.; Weiser, H. H.; Winter, A. R.

1965-01-01

A pad-plate method of assaying residual amounts of chlortetracycline (CTC) and oxytetracycline (OTC) using Bacillus cereus 213 was used to determine amounts of antibiotic left in tissues and eggs of poultry fed 1,000 and 200 ppm of CTC and OTC in basal feed mixtures. The effects of various methods of cooking the tissues and eggs and the potentiating effect of terephthalic acid (TPA) were studied. It was found that normal methods of roasting, frying, and autoclaving poultry tissue destroyed all residual CTC and OTC, even with the potentiating effect of TPA. The largest amounts of residual antibiotic were found in the liver, then breast, and then thigh tissue when assayed for CTC. Tissue assays for CTC revealed that it was not taken up as extensively as CTC and the largest amounts were found in the liver, then breast. OTC residue was seldom found in the thigh tissue. Terephthalic acid in 0.5% concentration increased the concentration found in all cases. Cooking by poaching and scrambling eggs did not destroy the antibiotic in all cases. PMID:14264853

Magnetite Nanoparticles Coated with Rifampicin and Chlortetracycline for Drug Delivery Applications

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Nadejde, Claudia; Ciurlica, Ecaterina Foca-nici; Creanga, Dorina; Carlescu, Aurelian; Badescu, Vasile

2010-01-01

Four types of biocompatible magnetic fluids based on superparamagnetic nanoparticles with Fe 3 O 4 cores were functionalized with antibiotics (rifampicin or chlortetracycline) as potential candidates for in vivo biomedical applications, such as magnetically controlled drug delivery. The synthesis consisted in coprecipitation of iron oxide in basic, as well as in acid medium, followed by the dispersion of the resulted magnetite nanoparticles in aqueous solution containing the antibiotic. The chosen method to prepare the magnetite-core/drug-shell systems avoided intermediate organic coating of the magnetic nanoparticles. Comparative analysis of the rheological features of the aqueous magnetic fluid samples was performed. The structural features of the coated magnetic particles were investigated by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometry (VSM). Good crystallinity and adequate stability in time were evidenced. Drug delivery curves were spectrophotometrically provided.

Degradation and toxicity assessment of sulfamethoxazole and chlortetracycline using electron beam, ozone and UV

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Kim, Tae-Hun; Kim, Sang Don; Kim, Hyun Young; Lim, Seung Joo; Lee, Myunjoo; Yu, Seungho

2012-01-01

Highlights: ► The degradation efficiency and trends for antibiotics were different between AOPs. ► The toxicities of target antibiotics were mainly affected by parent compounds. ► E-beam was electrically more energy efficient than ozone and UV-C. ► Application of AOPs should be considered according to the types of pharmaceuticals. - Abstract: Recently, the occurrence of antibiotics in sewage treatment plant effluent, as well as drinking water, has raised concern about their potential impacts on the environment and public health. Antibiotics are found in surface and ground waters, which indicate their ineffective removal by conventional wastewater treatment processes. Therefore, advanced oxidation processes (AOPs) have received considerable attention for the removal of antibiotics. This study was conducted to evaluate the degradation and mineralization of antibiotics (sulfamethoxazole and chlortetracycline) using an electron beam, ozone and UV, and the change of toxicity. Also, the electrical energy consumption based on the EE/O parameter (the electrical energy required per order of pollutants removal in 1 m 3 wastewater) was used to quantify the energy cost associated with the different AOPs (electron beam, ozone and UV) for the degradation of antibiotics. The results showed that an electron beam effective for the removals of both sulfamethoxazole and chlortetracycline in aqueous solutions. However, degradation of the target compounds by ozone and UV showed different trends. The oxidation efficiency of each organic compound was very dependent upon the AOP used. Algal toxicity was significantly reduced after each treatment. However, based on the electrical energy, the electron beam was more efficient than ozone and UV. Electron beam treatment could be an effective and safe method for the removal of antibiotic compounds.

Effects of Ceftiofur and Chlortetracycline on the Resistome of Feedlot Cattle.

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Weinroth, Margaret D; Scott, H Morgan; Norby, Bo; Loneragan, Guy H; Noyes, Noelle R; Rovira, Pablo; Doster, Enrique; Yang, Xiang; Woerner, Dale R; Morley, Paul S; Belk, Keith E

2018-05-04

Treatment of food producing animals with antimicrobial drugs (AMD) is controversial because of concerns regarding promotion of antimicrobial resistance (AMR). To investigate this concern, resistance genes in metagenomic bovine fecal samples during a clinical trial were analyzed to assess the impacts of treatment on beef feedlot cattle resistomes. Four groups of cattle were exposed, using a 2x2 factorial design, to different regimens of antimicrobial treatment. Injections of ceftiofur crystalline free acid (a third generation cephalosporin) were used to treat all cattle in treated pens vs. only a single animal, and chlortetracycline was included in the feed of all cattle in a pen vs. no treatment. On days 0 and 26, respectively, pre- and post-trial fecal samples were collected and resistance genes were characterized using shotgun metagenomics. Treatment with ceftiofur was not associated with changes to β-lactam resistance genes. However, cattle fed chlortetracycline had a significant increase in relative abundance of tetracycline resistance genes. There was also an increase of an AMR class not administered during the study-a possible indicator of co-selection of resistance genes. Samples analyzed in this study had previously been evaluated by culture characterization ( E. coli and Salmonella ) and qPCR of metagenomic fecal DNA, which allowed comparison of results with this study. In the majority of samples, genes that were selectively enriched through culture and qPCR were not identified through shotgun metagenomic sequencing in this study, suggesting that changes previously documented did not reflect changes affecting the majority of bacterial genetic elements found in the predominate fecal resistome. Importance Despite significant concerns about public health implications of AMR in relation to use of AMD in food animals, there are many unknowns about the long and short term impact of common uses of AMD for treatment, control, and prevention of disease

Complexation in two-component chlortetracycline-melanin solutions

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Lapina, V. A.; Pershukevich, P. P.; Dontsov, A. E.; Bel'Kov, M. V.

2008-01-01

The spectra and kinetics of fluorescence of two-component solutions of the chlortetracycline (CHTC)-DOPA-melanin (melanin or ME) system in water have been investigated. The data obtained have been compared to similar data for solutions of CHTC-melanosome from bull eye (MB), which contains natural melanin, in K-phosphate buffer at pH 7.4. The overall results indicate the occurrence of complexation between molecules of CHTC and ME as they are being excited. The studies of complexation in the solution of CHTC-MB in the buffer are complicated by the formation of a CHTC-buffer complex. The effect of optical radiation in the range 330-750 nm on the CHTC-ME complex shows selectivity: the greatest change in the spectrum occurs when the wavelength of the exciting radiation coincides with the long-wavelength band maximum of the fluorescence excitation spectrum of the CHTC-ME complex in aqueous solution. In this range, CHTC and especially ME show high photochemical stability. The nature of the radiation effect on the studied compounds in the hard UV range (λ < 330 nm) differs greatly from that in the range 330-750 nm. It is apparently accompanied by significant photochemical transmutations of all system components. By comparing the characteristics of the CHTC-ME systems with those of the related drug doxycycline (DC-ME), the conclusion has been made that the chlorine atom plays a vital role in formation of the short-wavelength band in the fluorescence spectrum of the CHTC-ME complex.

Synthesis and characterization of poly(acrylic acid)-g-sodium alginate hydrogel initiated by gamma irradiation for controlled release of chlortetracycline HCl

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Mohamed, S.F.; Mahmoud, G.A.; Taleb, M.F.A.

2013-01-01

pH-Sensitive hydrogel was synthesized by gamma radiation crosslinking for sodium alginate extracted from the marine brown alga Turbinaria decurrens and acrylic acid. Preparation of the hydrogels involved free radical polymerization of a combination of acrylic acid (w = 0.2) and different contents of sodium alginate (w = 0.05, 0.10, and 0.15) in aqueous solution using gamma rays of a 60 Co source at an irradiation dose rate of 1.2 kGy/h. The swelling behavior of the prepared hydrogel was determined by investigating the swelling time, pH of medium, and alginate content in the hydrogel. The results showed that the hydrogel reached the equilibrium swelling state in water after 6 h. The hydrogel was found to be pH responsive. The drug loading and in vitro release properties of the hydrogel were also evaluated using chlortetracycline hydrochloride as the model drug. The adsorption isotherm studies by batching techniques under the effect of different initial feed concentrations of drug, different pH values, and different sodium alginate content of the adsorbent hydrogel were investigated. The diffusion of chlortetracycline hydrochloride within the hydrogel was found to be of non-Fickian character. The kinetic parameters such as the diffusion exponent, diffusion constant, and diffusion coefficient were also evaluated. (author)

Effects of chlortetracycline amended feed on anaerobic sequencing batch reactor performance of swine manure digestion.

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Dreher, Teal M; Mott, Henry V; Lupo, Christopher D; Oswald, Aaron S; Clay, Sharon A; Stone, James J

2012-12-01

The effects of antimicrobial chlortetracycline (CTC) on the anaerobic digestion (AD) of swine manure slurry using anaerobic sequencing batch reactors (ASBRs) was investigated. Reactors were loaded with manure collected from pigs receiving CTC and no-antimicrobial amended diets at 2.5 g/L/d. The slurry was intermittently fed to four 9.5L lab-scale anaerobic sequencing batch reactors, two with no-antimicrobial manure, and two with CTC-amended manure, and four 28 day ASBR cycles were completed. The CTC concentration within the manure was 2 8 mg/L immediately after collection and 1.02 mg/L after dilution and 250 days of storage. CTC did not inhibit ASBR biogas production extent, however the volumetric composition of methane was significantly less (approximately 13% and 15% for cycles 1 and 2, respectively) than the no-antimicrobial through 56 d. CTC decreased soluble chemical oxygen demand and acetic acid utilization through 56 d, after which acclimation to CTC was apparent for the duration of the experiment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of antimicrobial compounds tylosin and chlortetracycline during batch anaerobic swine manure digestion.

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Stone, James J; Clay, Sharon A; Zhu, Zhenwei; Wong, Kwok L; Porath, Laura R; Spellman, Garth M

2009-10-01

Tylosin and chlortetracycline (CTC) are antimicrobial chemicals that are fed to >45% of the US swine herds at therapeutic and sub-therapeutic dosages to enhance growth rates and treat swine health problems. These compounds are poorly absorbed during digestion so that the bioactive compound or metabolites are excreted. This study investigated the degradation and stabilization of swine manure that contained no additives and compared the observed processes with those of manure containing either tylosin or CTC. The batch anaerobic incubation lasted 216 days. The breakdown of insoluble organic matter through anaerobic hydrolysis reactions was faster for manure containing CTC compared with tylosin or no-antimicrobial treatments. Volatile fatty acid (VFA) accumulation, including acetate, butyrate, and propionate, was greater for CTC-containing manure compared to tylosin and no-antimicrobial treatments. The relative abundance of two aceticlastic methanogens, Methanosaetaceae and Methanosarcinaceae spp., were less for CTC manure than manure with no-antimicrobial treatment. In addition, generation of methane and carbon dioxide was inhibited by 27.8% and 28.4%, respectively, due to the presence of CTC. Tylosin effects on manure degradation were limited, however the relative abundance of Methanosarcinaceae spp. was greater than found in the CTC or no-antimicrobial manures. These data suggest that acetate and other C-1 VFA compounds would be effectively utilized during methanogenesis in the presence of tylosin.

Antibiotic degradation and microbial community structures during acidification and methanogenesis of swine manure containing chlortetracycline or oxytetracycline.

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Yin, Fubin; Dong, Hongmin; Zhang, Wanqin; Zhu, Zhiping; Shang, Bin

2018-02-01

Anaerobic digestion (AD) has been applied to animal manure stabilization, and antibiotics is frequently found in animal manure. However, antibiotic degradation and microbial community structures during two-stage AD (acidification and methanogenesis) remain poorly understood. This experiments on two-stage anaerobic swine manure digesters were performed to investigate the degradation mechanisms and effects of chlortetracycline (CTC) and oxytetracycline (OTC) on microbial community structures. Results showed that acidification and methanogenesis showed good degradation performance for manure containing CTC and OTC at 60 and 40 mg/kg·TS, respectively. CTC and OTC were degraded by 59.8% and 41.3% in the acidogenic stage and by 76.3% and 78.3% in the methanogenic stage, respectively. CTC and OTC negatively affected bacterial community in methanogenic and acidogenic stages, respectively. They also adversely influenced the archaeal species in the methanogenic stage. Two-stage AD was proposed to treat manure containing antibiotics and to reduce the negative effects of antibiotics on AD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Complexação da tetraciclina, da oxitetraciclina e da clortetraciclina com o catião cobre (II. Estudo potenciométrico Tetracycline, oxytetracycline and chlortetracycline complexation with copper (II. Potentiometric study

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Cristina M. C. M. Couto

2000-08-01

Full Text Available Stability constants of complexes formed by copper (II with three different tetracyclines (tetracycline, oxytetracycline and chlortetracycline have been determined potentiometrically with an automatic system in aqueous medium at 25,0 ± 0,2 ºC and I = 0,1 mol L-1 NaNO3. The protonation constants of the three tetracyclines were also determined under the same conditions. The distribution of the complexes was then simulated at therapeutic levels of the drugs.

A novel biochar derived from cauliflower (Brassica oleracea L.) roots could remove norfloxacin and chlortetracycline efficiently.

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Qin, Tingting; Wang, Zhaowei; Xie, Xiaoyun; Xie, Chaoran; Zhu, Junmin; Li, Yan

2017-12-01

The biochar was prepared by pyrolyzing the roots of cauliflowers, at a temperature of 500 °C under oxygen-limited conditions. The structure and characteristics of the biochar were examined using scanning electron microscopy, an energy dispersive spectrometer, a zeta potential analyzer, and Fourier transform infrared spectroscopy. The effects of the temperature, the initial pH, antibiotic concentration, and contact time on the adsorption of norfloxacin (NOR) and chlortetracycline (CTC) onto the biochar were investigated. The adsorption kinetics of NOR and CTC onto the biochar followed the pseudo-second-order kinetic and intra-particle diffusion models. The adsorption isotherm experimental data were well fitted to the Langmuir and Freundlich isotherm models. The maximum adsorption capacities of NOR and CTC were 31.15 and 81.30 mg/g, respectively. There was little difference between the effects of initial solution pH (4.0-10.0) on the adsorption of NOR or CTC onto the biochar because of the buffering effect. The biochar could remove NOR and CTC efficiently in aqueous solutions because of its large specific surface area, abundant surface functional groups, and particular porous structure. Therefore, it could be used as an excellent adsorbent material because of its low cost and high efficiency and the extensive availability of the raw materials.

Effects of chlortetracycline and copper on tetracyclines and copper resistance genes and microbial community during swine manure anaerobic digestion.

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Wang, Rui; Chen, Meixue; Feng, Feng; Zhang, Junya; Sui, Qianwen; Tong, Juan; Wei, Yuansong; Wei, Dongbin

2017-08-01

As antibiotic and heavy metals are over used in the livestock industry, animal manure is a reservoir of antibiotic resistance genes (ARGs). Anaerobic digestion has been reported to have the potential to reduce ARGs. However, few studies investigated whether reduction of ARGs would be affected by different external pressures including antibiotics and heavy metals during anaerobic digestion. The purpose of this study was thus to investigate effects of both chlortetracycline (CTC) and Cu on reduction of ARGs, heavy metal resistance genes (HMRGs) and mobile genetic elements (MGEs) during the swine manure anaerobic digestion. The results showed that the predominant ARGs (tetO, tetW, tetX, tetL) could be effectively reduced (approximately 1.00 log copies/g TS) through mesophilic anaerobic digestion. Microbial community evolution was the main driver. It was interesting that Treponema might indicate the termination of anaerobic digestion and compete with ARGs host bacteria. Addition of CTC, Cu and CTC+Cu affected microbial community change and hindered removal of ARGs, especially, CTC+Cu seriously affected Treponema and ARGs during anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of the chlortetracycline addition method on methane production from the anaerobic digestion of swine wastewater.

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Huang, Lu; Wen, Xin; Wang, Yan; Zou, Yongde; Ma, Baohua; Liao, Xindi; Liang, Juanboo; Wu, Yinbao

2014-10-01

Effects of antibiotic residues on methane production in anaerobic digestion are commonly studied using the following two antibiotic addition methods: (1) adding manure from animals that consume a diet containing antibiotics, and (2) adding antibiotic-free animal manure spiked with antibiotics. This study used chlortetracycline (CTC) as a model antibiotic to examine the effects of the antibiotic addition method on methane production in anaerobic digestion under two different swine wastewater concentrations (0.55 and 0.22mg CTC/g dry manure). The results showed that CTC degradation rate in which manure was directly added at 0.55mg CTC/g (HSPIKE treatment) was lower than the control values and the rest of the treatment groups. Methane production from the HSPIKE treatment was reduced (pdigesters, and the total nitrogen of the 0.55mg CTC/kg manure collected from mediated swine was significantly higher than the other values. Therefore, different methane production under different antibiotic addition methods might be explained by the microbial activity and the concentrations of antibiotic intermediate products and metabolites. Because the primary entry route of veterinary antibiotics into an anaerobic digester is by contaminated animal manure, the most appropriate method for studying antibiotic residue effects on methane production may be using manure from animals that are given a particular antibiotic, rather than adding the antibiotic directly to the anaerobic digester. Copyright © 2014. Published by Elsevier B.V.

From illite/smectite clay to mesoporous silicate adsorbent for efficient removal of chlortetracycline from water.

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Wang, Wenbo; Tian, Guangyan; Zong, Li; Zhou, Yanmin; Kang, Yuru; Wang, Qin; Wang, Aiqin

2017-01-01

A series of mesoporous silicate adsorbents with superior adsorption performance for hazardous chlortetracycline (CTC) were sucessfully prepared via a facile one-pot hydrothermal reaction using low-cost illite/smectite (IS) clay, sodium silicate and magnesium sulfate as the starting materials. In this process, IS clay was "teared up" and then "rebuilt" as new porous silicate adsorbent with high specific surface area of 363.52m 2 /g (about 8.7 folds higher than that of IS clay) and very negative Zeta potential (-34.5mV). The inert SiOSi (Mg, Al) bonds in crystal framework of IS were broken to form Si(Al) O - groups with good adsorption activity, which greatly increased the adsorption sites served for holding much CTC molecules. Systematic evaluation on adsorption properties reveals the optimal silicate adsorbent can adsorb 408.81mg/g of CTC (only 159.7mg/g for raw IS clay) and remove 99.3% (only 46.5% for raw IS clay) of CTC from 100mg/L initial solution (pH3.51; adsorption temperature 30°C; adsorbent dosage, 3g/L). The adsorption behaviors of CTC onto the adsorbent follows the Langmuir isotherm model, Temkin equation and pseudo second-order kinetic model. The mesopore adsorption, electrostatic attraction and chemical association mainly contribute to the enhanced adsorption properties. As a whole, the high-efficient silicate adsorbent could be candidates to remove CTC from the wastewater with high amounts of CTC. Copyright © 2016. Published by Elsevier B.V.

Removal of chlortetracycline from spiked municipal wastewater using a photoelectrocatalytic process operated under sunlight irradiations

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Daghrir, Rimeh, E-mail: rimeh.daghrir@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre Eau, Terre et Environnement, 490 rue de la Couronne, Québec, Qc G1K 9A9 (Canada); Drogui, Patrick, E-mail: patrick.drogui@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre Eau, Terre et Environnement, 490 rue de la Couronne, Québec, Qc G1K 9A9 (Canada); Delegan, Nazar, E-mail: delegan@emt.inrs.ca [Institut National de la Recherche Scientifique, INRS-Énergie, Matériaux et Télécommunications, 1650 Blvd. Lionel-Boulet, Varennes, Qc J3X 1S2 (Canada); El Khakani, My Ali, E-mail: elkhakani@emt.inrs.ca [Institut National de la Recherche Scientifique, INRS-Énergie, Matériaux et Télécommunications, 1650 Blvd. Lionel-Boulet, Varennes, Qc J3X 1S2 (Canada)

2014-01-01

The degradation of chlortetracycline in synthetic solution and in municipal effluent was investigated using a photoelectrocatalytic oxidation process under visible irradiation. The N-doped TiO{sub 2} used as photoanode with 3.4 at.% of nitrogen content was prepared by means of a radiofrequency magnetron sputtering (RF-MS) process. Under visible irradiation, higher photoelectrocatalytic removal efficiency of CTC was recorded using N-doped TiO{sub 2} compared to the conventional electrochemical oxidation, direct photolysis and photocatalysis processes. The photoelectrocatalytic process operated at 0.6 A of current intensity during 180 min of treatment time promotes the degradation of 99.1 ± 0.1% of CTC. Under these conditions, removal rates of 85.4 ± 3.6%, 87.4 ± 3.1% and 55.7 ± 2.9% of TOC, TN and NH{sub 4}{sup +} have been recorded. During the treatment, CTC was mainly transformed into CO{sub 2} and H{sub 2}O. The process was also found to be effective in removing indicator of pathogens such as fecal coliform (log-inactivation was higher than 1.2 units). - Highlights: •PECO process is a feasible technology for the treatment of MWW contaminated by CTC. •99.1% ± 0.1% of CTC was degraded by PECO using N-doped TiO{sub 2}. •85.4% ± 3.6% of TOC removal and 97.5% ± 1.2% of COD removal were achieved. •87.4% ± 3.1% of TN removal and 55.7% ± 2.9% of NH{sub 4}{sup +} removal were recorded. •More than 94% of fecal coliform was removed (abatement > 1.2-log units)

Effects of chlortetracycline, Cu and their combination on the performance and microbial community dynamics in swine manure anaerobic digestion.

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Wang, Rui; Zhang, Junya; Liu, Jibao; Yu, Dawei; Zhong, Hui; Wang, Yawei; Chen, Meixue; Tong, Juan; Wei, Yuansong

2018-05-01

Swine manure was typical for the combined pollution of heavy metals and antibiotics. The effects of widely used veterinary antibiotic chlortetracycline (CTC), Cu and their combination on swine manure anaerobic digestion performance and microbial community have never been investigated. Thus, four 2L anaerobic digestion reactors were established including reactor A (control), B (CTC spiked by 0.5g/kg dry weight, dw), C (Cu spiked by 5g/kg dw) and D (combination of CTC, 0.5g/kg dw, and Cu, 5g/kg dw), and dynamics of bacterial and archaeal community structure was investigated using high throughput sequencing method. Results showed that addition of CTC and Cu separately could increase the total biogas production by 21.6% and 15.8%, respectively, while combination of CTC and Cu severely inhibited anaerobic digestion (by 30.3%). Furthermore, corresponding to different stages and reactors, four kinds of microbes including bacteria and archaea were described in detail, and the effects of CTC, Cu and their combination mainly occurred at hydrolysis and acidification phases. The addition of Cu alone changed the dynamics of archaeal community significantly. It was genus Methanomassiliicoccus that dominated at the active methane production for A, B and D, while it was genus Methanobrevibacter and Methanoculleus for C. Copyright © 2017. Published by Elsevier B.V.

Effect of anaerobic digestion temperature on odour, coliforms and chlortetracycline in swine manure or monensin in cattle manure.

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Varel, V H; Wells, J E; Shelver, W L; Rice, C P; Armstrong, D L; Parker, D B

2012-04-01

This study evaluated the effect of anaerobic digestion at 22, 38 and 55°C on odour, coliforms and chlortetracycline (CTC) in swine manure or monensin (MON) in cattle manure. Swine or cattle were fed the respective growth promotant, manure was collected, and 2-l laboratory methane digesters were established at the various temperatures and sampled over 25 or 28 days. After 21 days, the concentration of CTC in the 22, 38 and 55°C swine digester slurries decreased 7, 80 and 98%, respectively. Coliforms in the 22°C digester slurries were still viable after 25 days; however, they were not detectable in the 38 and 55°C slurries after 3 and 1 days, respectively. After 28 days, the concentration of MON in the 22, 38 and 55°C cattle digester slurries decreased 3, 8 and 27%, respectively. Coliforms in the 22°C cattle digester slurries were still viable after 28 days; however, they were not detectable in the 38 and 55°C slurries after 14 and 1 days, respectively. These studies indicate that anaerobic digestion at 38 or 55°C may be an effective treatment to reduce coliforms and CTC; however, it is not an effective treatment to reduce MON. More studies are needed to determine which pharmaceuticals are susceptible to degradation by a specific manure treatment to prevent negative environmental consequences. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Residues of chlortetracycline, doxycycline and sulfadiazine-trimethoprim in intestinal content and feces of pigs due to cross-contamination of feed.

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Peeters, Laura E J; Daeseleire, Els; Devreese, Mathias; Rasschaert, Geertrui; Smet, Annemieke; Dewulf, Jeroen; Heyndrickx, Marc; Imberechts, Hein; Haesebrouck, Freddy; Butaye, Patrick; Croubels, Siska

2016-09-20

Cross-contamination of feed with low concentrations of antimicrobials can occur at production, transport and/or farm level. Concerns are rising about possible effects of this contaminated feed on resistance selection in the intestinal microbiota. Therefore, an experiment with pigs was set up, in which intestinal and fecal concentrations of chlortetracycline (CTC), doxycycline (DOX) and sulfadiazine-trimethoprim (SDZ-TRIM) were determined after administration of feed containing a 3 % carry-over level of these antimicrobials. The poor oral bioavailability of tetracyclines resulted in rather high concentrations in cecal and colonic content and feces at steady-state conditions. A mean concentration of 10 mg/kg CTC and 4 mg/kg DOX in the feces was reached, which is higher than concentrations that were shown to cause resistance selection. On the other hand, lower mean levels of SDZ (0.7 mg/kg) and TRIM (< limit of detection of 0.016 mg/kg) were found in the feces, corresponding with the high oral bioavailability of SDZ and TRIM in pigs. The relation between the oral bioavailability and intestinal concentrations of the tested antimicrobials, may be of help in assessing the risks of cross-contaminated feed. However, future research is needed to confirm our results and to evaluate the effects of these detected concentrations on resistance selection in the intestinal microbiota of pigs.

Effects of chlortetracycline and copper supplementation on antimicrobial resistance of fecal Escherichia coli from weaned pigs.

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Agga, G E; Scott, H M; Amachawadi, R G; Nagaraja, T G; Vinasco, J; Bai, J; Norby, B; Renter, D G; Dritz, S S; Nelssen, J L; Tokach, M D

2014-06-01

Feed-grade chlortetracycline (CTC) and copper are both widely utilized in U.S. pig production. Cluster randomized experiment was conducted to evaluate the effects of CTC and copper supplementation in weaned pigs on antimicrobial resistance (AMR) among fecal Escherichia coli. Four treatment groups: control, copper, CTC, or copper plus CTC were randomly allocated to 32 pens with five pigs per pen. Fecal samples were collected weekly from three pigs per pen for six weeks. Two E. coli isolates per fecal sample were tested for phenotypic and genotypic resistance against antibiotics and copper. Data were analyzed with multilevel mixed effects logistic regression, multivariate probit analysis and discrete time survival analysis. CTC-supplementation was significantly (99% [95% CI=98-100%]) associated with increased tetracycline resistance compared to the control group (95% [95% CI=94-97%]). Copper supplementation was associated with decreased resistance to most of the antibiotics tested, including cephalosporins, over the treatment period. Overall, 91% of the E. coli isolates were multidrug resistant (MDR) (resistant to ≥3 antimicrobial classes). tetA and blaCMY-2 genes were positively associated (PpcoD were negatively associated with MDR. tetA and blaCMY-2 were positively associated with each other and in turn, these were negatively associated with both tetB and pcoD genes; which were also positively associated with one another. Copper minimum inhibitory concentration was not affected by copper supplementation or by pcoD gene carriage. CTC supplementation was significantly associated with increased susceptibilities of E. coli to copper (HR=7 [95% CI=2.5-19.5]) during treatment period. In conclusion, E. coli isolates from the nursery pigs exhibited high levels of antibiotic resistance, with diverse multi-resistant phenotypic profiles. The roles of copper supplementation in pig production, and pco-mediated copper resistance among E. coli in particular, need to be further

Effects of dietary polysavone (Alfalfa extract) and chlortetracycline supplementation on antioxidation and meat quality in broiler chickens.

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Dong, X F; Gao, W W; Su, J L; Tong, J M; Zhang, Q

2011-06-01

1. A total of 360 1-d-old male commercial Arbor Acre broiler chickens were randomly assigned to 5 groups (6 replicates of 12 birds each) to evaluate the dietary effects of polysavone (0·5, 1·0 and 1·5 g/kg), a natural extract from alfalfa, and 0·15 g/kg chlortetracycline (CTC) on growth performance, antioxidation and meat quality of broiler chickens. 2. Over the 6-week study, feed intake increased significantly with CTC supplementation and final body weight (BW) was significantly higher for 1·0 g/kg polysavone and 0·15 g/kg CTC treatments. Feed:gain ratio was not significantly affected by the dietary treatments. 3. At 3 weeks of age, serum total superoxide dismutase (T-SOD) activity for all polysavone treatments was significantly higher than controls, liver T-SOD activity in 1·5 g/kg polysavone group was significantly higher than the control and CTC groups, and serum glutathione peroxidase (GSHPx) activity for 1·5 g/kg polysavone and liver GSHPx activity in all polysavone groups were significantly higher than CTC. 4. At 6 weeks of age, serum and liver T-SOD activity in 1·5 g/kg polysavone group and liver GSHPx activity for all polysavone treatments were higher significantly than the control and CTC groups, and serum malondialdehyde (MDA) content for all polysavone treatments was significantly lower than CTC. 5. Breast muscle T-SOD activity and pH value at 6 weeks of age were significantly higher and MDA content was significantly lower in 1·0 and 1·5 g/kg polysavone groups than in the control and CTC groups. Breast muscle shear force was significantly lower in l·5 g/kg polysavone group compared with the control, and drip loss for all polysavone treatments was significantly lower than CTC. 6. It was indicated that polysavone modulates antioxidation and modifies meat quality, but with no adverse effect on performance of broiler chickens, and that CTC can be beneficial to performance but has no beneficial effect on antioxidant function or meat quality.

Effects of chlortetracycline and copper supplementation on the prevalence, distribution, and quantity of antimicrobial resistance genes in the fecal metagenome of weaned pigs.

Science.gov (United States)

Agga, Getahun E; Scott, H Morgan; Vinasco, Javier; Nagaraja, T G; Amachawadi, Raghavendra G; Bai, Jianfa; Norby, Bo; Renter, David G; Dritz, Steve S; Nelssen, Jim L; Tokach, Mike D

2015-05-01

Use of in-feed antibiotics such as chlortetracycline (CTC) in food animals is fiercely debated as a cause of antimicrobial resistance in human pathogens; as a result, alternatives to antibiotics such as heavy metals have been proposed. We used a total community DNA approach to experimentally investigate the effects of CTC and copper supplementation on the presence and quantity of antimicrobial resistance elements in the gut microbial ecology of pigs. Total community DNA was extracted from 569 fecal samples collected weekly over a 6-week period from groups of 5 pigs housed in 32 pens that were randomized to receive either control, CTC, copper, or copper plus CTC regimens. Qualitative and quantitative PCR were used to detect the presence of 14 tetracycline resistance (tet) genes and to quantify gene copies of tetA, tetB, blaCMY-2 (a 3rd generation cephalosporin resistance gene), and pcoD (a copper resistance gene), respectively. The detection of tetA and tetB decreased over the subsequent sampling periods, whereas the prevalence of tetC and tetP increased. CTC and copper plus CTC supplementation increased both the prevalence and gene copy numbers of tetA, while decreasing both the prevalence and gene copies of tetB. In summary, tet gene presence was initially very diverse in the gut bacterial community of weaned pigs; thereafter, copper and CTC supplementation differentially impacted the prevalence and quantity of the various tetracycline, ceftiofur and copper resistance genes resulting in a less diverse gene population. Published by Elsevier B.V.

The action of certain antibiotics and ether on swine enzootic pneumonia.

Science.gov (United States)

Huhn, R G

1971-01-01

The susceptibility of Mycoplasma hyopneumoniae to the action of three antibiotics and diethyl ether was determined. Infected swine were used in an in vivo sensitivity detection system. The parameter of susceptibility was lesion prophylaxis. In vivo, Mycoplasma hyopneumoniae appeared to be resistant to diethyl ether, tylosin tartrate, and erythromycin, but was susceptible to the action of chlortetracycline. Chlortetracycline was effective in preventing the development of lesions when given at levels which would be practical in commercial swine operations.

Toxicity of tetracyclines and tetracycline degradation products to environmentally relevant bacteria, including selected tetracycline-resistant bacteria

DEFF Research Database (Denmark)

Halling-Sørensen, B.; Sengeløv, G.; Tjørnelund, J.

2002-01-01

Tetracyclines used in veterinary therapy invariably will find their way as parent compound and degradation products to the agricultural field. Major degradation products formed due to the limited stability of parent tetracyclines (tetracycline, chlortetracycline, and oxytetracycline) in aqueous...... at the same concentration level as tetracycline, chlortetracycline, and oxytetracycline on both the sludge and the tetracycline-sensitive soil bacteria. Further, both 5a,6-anhydrotetracychne and 5a,6-anhydrochlortetracycline had potency on tetracycline-resistant bacteria supporting a mode of action different...

Elimination patterns of worldwide used sulfonamides and tetracyclines during anaerobic fermentation.

Science.gov (United States)

Spielmeyer, Astrid; Breier, Bettina; Groißmeier, Kathrin; Hamscher, Gerd

2015-10-01

Antibiotics such as sulfonamides and tetracyclines are frequently used in veterinary medicine. Due to incomplete absorption in the animal gut and/or unmetabolized excretion, the substances can enter the environment by using manure as soil fertilizer. The anaerobic fermentation process of biogas plants is discussed as potential sink for antibiotic compounds. However, negative impacts of antibiotics on the fermentation process are suspected. The elimination of sulfadiazine, sulfamethazine, tetracycline and chlortetracycline in semi-continuous lab-scale fermenters was investigated. Both biogas production and methane yield were not negatively affected by concentrations up to 38 mg per kg for sulfonamides and 7 mg per kg for tetracyclines. All substances were partly eliminated with elimination rates between 14% and 89%. Both matrix and structure of the target molecule influenced the elimination rate. Chlortetracycline was mainly transformed into iso-chlortetracycline. In all other cases, the elimination pathways remained undiscovered; however, sorption processes seem to have a negligible impact. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enzyme-linked immunosorbent assay for ultratrace determination of antibiotics in aqueous samples.

Science.gov (United States)

Kumar, Kuldip; Thompson, Anita; Singh, Ashok K; Chander, Yogesh; Gupta, Satish C

2004-01-01

Two commercially available enzyme-linked immunosorbent assay (ELISA) kits that are commonly used for tylosin or tetracycline residues in meat and milk were adapted for ultratrace analysis of these antibiotics in surface and ground waters. These two antibiotics are commonly fed to swine, turkeys, and cattle at subtherapeutic doses for growth promotion purposes. Both ELISA techniques were found to be highly sensitive and selective for the respective antibiotics with detection limits of 0.10 and 0.05 microg L(-1) for tylosin and tetracycline, respectively. The recovery of both tylosin and tetracycline from spiked samples of lake waters, runoff samples, soil saturation extracts, and nanopure water was close to 100%. Tetracycline ELISA was highly specific for tetracycline and chlortetracycline but not for other forms of tetracycline (oxytetracycline, demeclocycline, and doxycycline). Analysis of a few liquid swine manure samples by liquid chromatography-mass spectrometry (LC-MS) showed lower concentrations for chlortetracycline as compared with concentrations obtained using ELISA. However, the concentrations of tylosin from ELISA were comparable with that of LC-MS. The lower concentrations of chlortetracycline obtained by LC-MS in manure samples indicate the presence of other similar or transformed compounds that were detected by ELISA but not determined by LC-MS. These results indicate that both ELISA kits can be useful tools for low-cost screening of tylosin, tetracycline, and chlortetracycline in environmental waters. Furthermore, both ELISA procedures are rapid, portable, and easily adaptable for testing of multiple samples simultaneously.

Otimização e validação de método para determinação de resíduos de oxitetraciclina, tetraciclina e clortetraciclina em leite por cromatografia líquida de alta eficiência Optimization and validation of a method for determination of oxytetracycline, tetracycline and chlortetracycline residues in milk by high performance liquid chromatography

Directory of Open Access Journals (Sweden)

Iara C. A. Ruela

2005-03-01

Full Text Available Um método para determinação de resíduos de oxitetraciclina, tetraciclina e clortetraciclina em leite por cromatografia líquida de alta eficiência foi otimizado e validado. Ensaios intralaboratoriais empregando soluções padrão, brancos de amostras e amostras adicionadas de soluções padrão dos antimicrobianos foram realizados para avaliação da linearidade, seletividade, exatidão, precisão, limites de detecção e de quantificação do método. As amostras foram homogeneizadas, tratadas com solução tampão de succinato de sódio pH 4,0 e centrifugadas, descartando-se o precipitado. As tetraciclinas foram removidas do sobrenadante por quelação com íons cobre reversivelmente ligados à resina quelante e eluídas com tampão McIlvaine-EDTA pH 4,0. As médias de recuperação para as tetraciclinas foram de 76,2 a 104,9% com coeficiente de variação na faixa de 1,4 a 18,9%. Limites de detecção de 10, 15 e 40ng/mL e limites de quantificação de 10, 20 e 50ng/mL foram determinados para oxitetraciclina, tetraciclina e clortetraciclina, respectivamente.A method for determination of oxytetracycline, tetracycline and chlortetracycline residues in milk by high performance liquid chromatography was optimized and validated. Linearity, selectivity, trueness, precision, limits of detection and quantitation were evaluated by in-house validation procedures employing reference materials, sample blanks and spiked samples. Milk samples were homogenized, treated with sodium succinate pH 4.0 buffer and centrifuged, discarding the precipitate. Tetracyclines were removed from the supernatant by chelating with metal ions bound to a chelating resin and eluted with McIlvaine-EDTA pH 4.0 buffer. Mean recoveries for tetracyclines ranged from 76.2 to 104.9% with coefficients of variation from 1.4 to 18.9%. Detection limits of 10, 15 and 40ng/mL and quantitation limits of 10, 20 and 50ng/mL were determined for oxytetracycline, tetracycline and

Compatibility of a combination of tiamulin plus chlortetracycline with salinomycin in feed during a long-term co-administration in broilers.

Science.gov (United States)

Islam, K M S; Afrin, S; Khan, M J; Das, P M; Hassan, M M; Valks, M; Burch, D G S; Pesti, G M

2008-08-01

The pleuromutilin antibiotic tiamulin (TIA) is known to produce a negative interaction in broilers when administered in combination with several ionophore anticoccidials such as salinomycin (SAL). Chlortetracycline (CTC), when administered simultaneously with TIA, has demonstrated a synergistic antimicrobial effect. A 35-d feeding study was conducted in cages to evaluate the interaction effect of a combination of TIA plus CTC at increasing inclusion levels when administered concurrently with SAL. A total of 200 one-day-old broiler chicks were distributed into 4 groups, and each group consisted of 5 cages containing 10 birds in each. Replicate cages were distributed randomly. Feed for all groups contained 60 ppm SAL, but additionally, 0, 20, 30, and 50 ppm TIA and 0, 60, 90, and 150 ppm CTC were included, respectively. Several enzymes (creatine phosphokinase, lactate dehydrogenase, and aspartate aminotransferase) were determined from blood samples taken at the end of the trial. Blood samples were also collected during d 0, 19, and 35 and were analyzed for antibody titers against Mycoplasma gallisepticum and Mycoplasma synoviae. Necropsy of a few birds (20, 8, 20, 12, and 12 on d 7, 14, 21, 28, and 35, respectively) was conducted at weekly intervals. Results indicated that there was a significant depression of weight gain (P < 0.05) in group 4 (TIA 50 + CTC 150) only. The final weights were 1,809 +/- 130, 1,859 +/- 52, 1,703 +/- 47, and 1,617 +/- 98 g for groups 1 (TIA 0 + CTC 0), 2 (TIA 20 + CTC 60), 3 (TIA 30 + CTC 90), and 4 (TIA 50 + CTC 150), respectively. However, feed intake and feed conversion efficiency (g of weight gain/kg of feed intake) were not significantly affected in any of the groups. There was no dose-related adverse effect on mortality or clinical signs exhibited during the trial, and this was supported by necropsy. Maternally derived antibodies against M. gallisepticum were present at the beginning of the trial but disappeared within 19 d

Effect of composting and soil type on dissipation of veterinary antibiotics in land-applied manures.

Science.gov (United States)

Chen, Chaoqi; Ray, Partha; Knowlton, Katharine F; Pruden, Amy; Xia, Kang

2018-04-01

The objective of this study was to determine the fate of commonly used veterinary antibiotics in their naturally excreted form when manure-based amendments are applied to soil. Beef cattle were administered sulfamethazine, tylosin, and chlortetracycline and dairy cows were treated with pirlimycin. The resulting manure was composted for 42 d under static or turned conditions and applied at agronomic N rates to sandy, silt, and silty clay loam soils and compared with amendment with corresponding raw manures in sacrificial microcosms over a 120-day period. Antibiotic dissipation in the raw manure-amended soils followed bi-phasic first order kinetics. The first phase half-lives for sulfamethazine, tylosin, chlortetracycline, and pirlimycin ranged from 6.0 to 18, 2.7 to 3.7, 23 to 25, and 5.5-8.2 d, respectively. During the second phase, dissipation of sulfamethazine was negligible, while the half-lives for tylosin, chlortetracycline, and pirlimycin ranged from 41 to 44, 75 to 144, and 87-142 d, respectively. By contrast, antibiotic dissipation in the compost-amended soils followed single-phase first order kinetics with negligible dissipation of sulfamethazine and half-lives of tylosin and chlortetracycline ranging from 15 to 16 and 49-104 d, respectively. Pirlimycin was below the detection limit in the compost-amended soils. After incubating 120 d, antibiotics in compost-amended soils (up to 3.1 μg kg -1 ) were significantly lower than in manure-amended soils (up to 19 μg kg -1 , p soil type on the dissipation. Risk assessment suggested that composting can reduce antibiotic resistance selection potential in manure-amended soils. Copyright © 2018 Elsevier Ltd. All rights reserved.

Compatibility of a combination of tiamulin and chlortetracycline with salinomycin in feed during a pulsed medication program coadministration in broilers.

Science.gov (United States)

Islam, K M S; Afrin, S; Das, P M; Hassan, M M; Valks, M; Klein, U; Burch, D G S; Kemppainen, B W

2008-12-01

In an earlier study, the continuous medication of broiler feed with a combination of tiamulin (TIA; 20 mg/kg), chlortetracycline (CTC; 60 mg/kg), and the ionophore anticoccidial salinomycin (SAL; 60 mg/kg) caused an initial increase in BW and feed efficiency (FE; g of weight gain/kg of feed intake). However, as doses increased to combinations of 30 mg/kg of TIA and 90 mg/kg of CTC or 50 mg/kg of TIA and 150 mg/kg of CTC, there was a dose-related reduction in growth rate and FE. This was thought to be due to the interaction between TIA and SAL. In this study, using a protocol similar to the previous trial, broiler chicks were administered SAL at 60 mg/kg via the feed and the same inclusion rates of TIA + CTC. However, instead of feeding the birds continuously, considering the cost of TIA and possibly to compensate for the depressed growth attributable to the interaction with SAL, they were pulse-dosed for 1 to 10 d and again at 21 to 27 d, and the whole trial lasted 35 d to see if the intermittent pulses might reduce production losses. A total of 200 straight-run 1-d-old broiler chicks (Hubbard classic) were randomly distributed into 4 groups, with each group consisting of 5 cages containing 10 birds. The 20 cages were allocated to the 4 treatment groups on a random basis. The control diet, containing only SAL at 60 mg/kg, was fed to all birds throughout the 35-d trial, including the period during the gaps between dosing (i.e., d 11 to 20 and d 28 to 35). Feed and water were available for the whole trial period. Several serum enzymes (creatine kinase, lactate dehydrogenase, and aspartate aminotransferase) were determined from blood samples taken on d 35. Blood samples were also collected at 1, 19, and 35 d of age and were examined for antibody titers to Mycoplasma gallisepticum and Mycoplasma synoviae. Necropsy and histopathology of the birds (n = >or=4) were conducted during weekly intervals. There was no significant difference in weight gain, feed intake, and FE

104 evaluation of microbiological purity of some brands of ...

African Journals Online (AJOL)

DR. AMINU

Keywords: Microbiological purity, tetracycline, contaminants, bacterial load, fungal load, microbiological ... Just like food substances, pharmaceutical products .... Malaysia. Chlortetracycline a. Mar. 2005. Mar. 2008. Ghana b. Aug. 2005. Aug.

Tetracycline resistance in semi-arid agricultural soils under long-term swine effluent application.

Science.gov (United States)

Popova, Inna E; Josue, Rosemarie D R; Deng, Shiping; Hattey, Jeffory A

2017-05-04

Annually, millions pounds of antibiotics are released unmetabolized into environment along with animal wastes. Accumulation of antibiotics in soils could potentially induce the persistence of antibiotic resistant bacteria. Antibiotics such as tetracyclines and tetracycline-resistant bacteria have been previously detected in fields fertilized with animal manure. However, little is known about the accumulation of tetracyclines and the development of tetracycline resistance in semi-arid soils. Here we demonstrate that continuous land application with swine effluent, containing trace amounts of chlortetracycline, does not necessarily induce tetracycline resistance in soil bacteria. Based on the testing of more than 3,000 bacteria isolated from the amended soils, we found no significant increase in the occurrence and level of chlortetracycline resistant bacteria in soils after 15 years of continuous swine effluent fertilization. To account for a possible transfer of tetracycline-resistant bacteria originated from the swine effluent to soils, we analyzed two commonly found tetracycline resistant genes, tet(O) and tet(M), in the swine effluent and fertilized soils. Both genes were present in the swine effluent, however, they were not detectable in soils applied with swine effluent. Our data demonstrate that agronomic application of manure from antibiotic treated swine effluent does not necessarily result in the development of antibiotic bacterial resistance in soils. Apparently, concentrations of chlortetracycline present in manure are not significant enough to induce the development of antibiotic bacterial resistance.

Chemical preservatives in foodstuffs IV. Prolongation of the keeping guality of fresh fish by antibiotics

Directory of Open Access Journals (Sweden)

Reino R. Linko

1961-01-01

Full Text Available A study has been made of the effect of antibiotics in the storage of fresh Baltic herring. Experiments were made with muscle homogenates, to which antibiotics were added, and whole fish and fillets, treated by means of dips in antibiotic solutions and storage in antibiotic ice. The temperatures studied were 2°C and 10°C. The antibiotics employed were chlortetracycline and oxytetracycline. It was observed that the antibiotics improved the keeping quality of Baltic herring. In dipping treatments, and in experiments with muscle homogenates, the favorable effect of the antibiotic was observable even at the early phase of the storage, whereas when antibiotic ice was used such effect was only discovered after about one week’s storage. In a comparison of chlortetracycline and oxytetracycline no essential differences were observed in their effectivity.

Construction of an extended range whole-cell tetracycline biosensor by use of the tet(M) resistance gene

DEFF Research Database (Denmark)

Bahl, Martin Iain; Hansen, Lars Hestbjerg; Sørensen, Søren Johannes

2005-01-01

protein gene. Tetracycline, oxytetracycline, chlortetracycline and minocycline all effectively induced the resulting Escherichia coli MC4100/pTGM biosensor and similar dose-response characteristics were recorded by flow cytometry for all four compounds. The novel tetracycline biosensor was responsive...

76 FR 17336 - New Animal Drugs; Amikacin Sulfate, Ampicillin Trihydrate, Ceftiofur Hydrochloride, Cephapirin...

Science.gov (United States)

2011-03-29

..., Ceftiofur Hydrochloride, Cephapirin Benzathine, Chlortetracycline, Fenbendazole, Formalin, Furosemide... (e)(3)(iii) to read as follows: Sec. 520.905a Fenbendazole suspension. * * * * * (e) * * * (2.... 520.905c, revise paragraph (e)(2)(iii) to read as follows: Sec. 520.905c Fenbendazole paste...

A Randomised Non-inferiority Trial on the Effect of an Antibiotic or Non-antibiotic Topical Treatment Protocol for Digital Dermatitis in Dairy Cattle : a knowledge summary

NARCIS (Netherlands)

Jorritsma, R.; Nielen, M.; Dotinga, Amarins

2017-01-01

Objective: Investigation of the therapeutic effect of a protocol using non-antibiotic Intra Epidine (IE) spray containing copper and zinc chelate on M2 digital dermatitis (DD) lesions compared to a treatment protocol using antibiotic chlortetracycline (CTC) spray for non-inferiority testing.

Drug residues recovered in feed after various feedlot mixer truck cleanout procedures.

Science.gov (United States)

Van Donkersgoed, Joyce; Sit, Dan; Gibbons, Nicole; Ramogida, Caterina; Hendrick, Steve

2010-01-01

A study was conducted to determine the effectiveness of two methods of equipment cleanout, sequencing or flushing, for reducing drug carryover in feedlot mixer trucks. Feed samples were collected from total mixed rations before and after various feed mixer equipment cleanout procedures. Medicated rations contained either 11 ppm of tylosin or 166 or 331 ppm of chlortetracycline. There were no differences between sequencing and flushing or between flushing with dry barley and flushing with barley silage in the median proportion of drug recovered in the next ration. A larger drug reduction was achieved using flush material at a volume of 10 versus 5% of the mixer capacity and mixing the flush material for 3 versus 4 min. Regardless of the drug or prescription concentrations in the total mixed rations or the equipment cleanout procedure used, concentrations of chlortetracycline and tylosin recovered were very low.

Antibiotic losses from unprotected manure stockpiles.

Science.gov (United States)

Dolliver, Holly A S; Gupta, Satish C

2008-01-01

Manure management is a major concern in livestock production systems. Although historically the primary concerns have been nutrients and pathogens, manure is also a source of emerging contaminants, such as antibiotics, to the environment. There is a growing concern that antibiotics in manure are reaching surface and ground waters and contributing to the development and spread of antibiotic resistance in the environment. One such pathway is through leaching and runoff from manure stockpiles. In this study, we quantified chlortetracycline, monensin, and tylosin losses in runoff from beef manure stockpiles during two separate but consecutive experiments representing different weather conditions (i.e., temperature and precipitation amount and form). Concentrations of chlortetracycline, monensin, and tylosin in runoff were positively correlated with initial concentrations of antibiotics in manure. The highest concentrations of chlortetracycline, monensin, and tylosin in runoff were 210, 3175, and 2544 microg L(-1), respectively. Relative antibiotic losses were primarily a function of water losses. In the experiment that had higher runoff water losses, antibiotic losses ranged from 1.2 to 1.8% of total extractable antibiotics in manure. In the experiment with lower runoff water losses, antibiotic losses varied from 0.2 to 0.6% of the total extractable antibiotics in manure. Manure analysis over time suggests that in situ degradation is an important mechanism for antibiotic losses. Degradation losses during manure stockpiling may exceed cumulative losses from runoff events. Storing manure in protected (i.e., covered) facilities could reduce the risk of aquatic contamination associated with manure stockpiling and other outdoor manure management practices.

Quantitative Campylobacter spp., antibiotic resistance genes, and veterinary antibiotics in surface and ground water following manure application: Influence of tile drainage control.

Science.gov (United States)

Frey, Steven K; Topp, Edward; Khan, Izhar U H; Ball, Bonnie R; Edwards, Mark; Gottschall, Natalie; Sunohara, Mark; Lapen, David R

2015-11-01

This work investigated chlortetracycline, tylosin, and tetracycline (plus transformation products), and DNA-based quantitative Campylobacter spp. and Campylobacter tetracycline antibiotic resistant genes (tet(O)) in tile drainage, groundwater, and soil before and following a liquid swine manure (LSM) application on clay loam plots under controlled (CD) and free (FD) tile drainage. Chlortetracycline/tetracycline was strongly bound to manure solids while tylosin dominated in the liquid portion of manure. The chlortetracycline transformation product isochlortetracycline was the most persistent analyte in water. Rhodamine WT (RWT) tracer was mixed with manure and monitored in tile and groundwater. RWT and veterinary antibiotic (VA) concentrations were strongly correlated in water which supported the use of RWT as a surrogate tracer. While CD reduced tile discharge and eliminated application-induced VA movement (via tile) to surface water, total VA mass loading to surface water was not affected by CD. At both CD and FD test plots, the biggest 'flush' of VA mass and highest VA concentrations occurred in response to precipitation received 2d after application, which strongly influenced the flow abatement capacity of CD on account of highly elevated water levels in field initiating overflow drainage for CD systems (when water level tile and groundwater became very low within 10d following application. Both Campylobacter spp. and Campylobacter tet(O) genes were present in groundwater and soil prior to application, and increased thereafter. Unlike the VA compounds, Campylobacter spp. and Campylobacter tet(O) gene loadings in tile drainage were reduced by CD, in relation to FD. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

21 CFR 558.311 - Lasalocid.

Science.gov (United States)

2010-04-01

...) Pasture cattle (slaughter, stocker, feeder cattle, and dairy and beef replacement heifers): For increased... per day. 021930017800 (xix) 300 Pasture cattle (slaughter, stocker, feeder cattle, and dairy and beef.... Chlortetracycline 500 to 4000. Pasture cattle (slaughter, stocker, feeder cattle, and dairy and beef replacement...

21 CFR 558.58 - Amprolium and ethopabate.

Science.gov (United States)

2010-04-01

... efficiency; as an aid in the prevention of coccidiosis Not for laying chickens; as lincomycin hydrochloride... coccidiosis Not for laying chickens; as lincomycin hydrochloride monohydrate; withdraw 5 d before slaughter... susceptible to chlortetracycline In low calcium feed containing 0.8% dietary calcium and 1.5% sodium sulfate...

Development of adsorptive membranes by confinement of activated biochar into electrospun nanofibers

Directory of Open Access Journals (Sweden)

Mehrdad Taheran

2016-11-01

Full Text Available Adsorptive membranes have many applications in removal of contaminants, such as heavy metals and organic contaminants from water. Recently, increasing concentrations of pharmaceutically active compounds, especially antibiotics, such as chlortetracycline in water and wastewater sources has raised concerns about their potentially adverse impacts on environment and human health. In this study, a series of polyacrylonitrile (PAN/activated biochar nanofibrous membranes (NFMs with different loadings of biochar (0–2%, w/w were fabricated using electrospinning. The morphology and structure of fabricated membranes was investigated by scanning electron microscopy, Fourier transform infrared and thermogravimetric analysis. The results showed that at 1.5% of biochar loading, the surface area reached the maximum value of 12.4 m2/g and beyond this loading value, agglomeration of particles inhibited fine interaction with nanofibrous matrix. Also, the adsorption tests using chlortetracycline showed that, under environmentally relevant concentrations, the fabricated adsorptive NFMs had a potential for removal of these types of emerging contaminants from water and wastewaters.

Characterization of Antibiotics and Antibiotic Resistance Genes on an Ecological Farm System

Directory of Open Access Journals (Sweden)

Songhe Zhang

2015-01-01

Full Text Available There is a growing concern worldwide about the prevalence of antibiotics and antibiotic resistance genes (ARGs on the farm. In this study, we investigated the distribution of seven antibiotics and ten ARGs in fresh and dried pig feces, in biogas slurry, and in grape-planting soil from an ecological farm. Antibiotics including sulfamethazine, norfloxacin, ofloxacin, tetracycline, oxytetracycline, and chlortetracycline were detected in these samples (except for sulfamethoxazole in dried feces. In general, antibiotics levels in samples were in the sequence: biogas slurry > fresh feces > soil or dried feces. Results of ecological risk assessments revealed that among the seven antibiotics chlortetracycline showed the highest ecological risk. Among the ten ARGs, sulI and tetO were the most prevalent on this ecological farm. There were positive correlations between certain ARGs and the corresponding antibiotics on this ecological farm. Therefore, continuous monitoring of antibiotics and their corresponding ARGs should be conducted in the agroecosystem near the concentrated animal farming operation systems.

21 CFR 556.500 - Oxytetracycline.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline. 556.500 Section 556.500 Food and... Residues of New Animal Drugs § 556.500 Oxytetracycline. (a) Acceptable daily intake (ADI). The ADI for total tetracycline residues (chlortetracycline, oxytetracycline, and tetracycline) is 25 micrograms per...

21 CFR 520.445b - Chlortetracycline powder.

Science.gov (United States)

2010-04-01

... administer this product with milk or milk replacers; administer 1 hour before or 2 hours after feeding milk or milk replacers; a withdrawal period has not been established in preruminating calves; do not use.... Control of chronic respiratory disease and air-sac infections caused by M. gallisepticum and E. coli. (2...

Use estimates of in-feed antimicrobials in swine production in the United States.

Science.gov (United States)

Apley, Michael D; Bush, Eric J; Morrison, Robert B; Singer, Randall S; Snelson, Harry

2012-03-01

When considering the development of antimicrobial resistance in food animals, comparing gross use estimates of different antimicrobials is of little value due to differences in potencies, duration of activity, relative effect on target and commensal bacteria, and mechanisms of resistance. However, it may be valuable to understand quantities of different antimicrobials used in different ages of swine and for what applications. Therefore, the objective of this project was to construct an estimate of antimicrobial use through the feed in swine production in the United States. Estimates were based on data from the National Animal Health Monitoring System (NAHMS) Swine 2006 Study and from a 2009 survey of swine-exclusive practitioners. Inputs consisted of number of pigs in a production phase, feed intake per day, dose of the antimicrobial in the feed, and duration of administration. Calculations were performed for a total of 102 combinations of antimicrobials (n=17), production phases (n=2), and reasons for use (n=3). Calculations were first conducted on farm-level data, and then extrapolated to the U.S. swine population. Among the nursery phase estimates, chlortetracycline had the largest estimate of use, followed by oxytetracycline and tilmicosin. In the grower/finisher phase, chlortetracycline also had the largest use estimate, followed by tylosin and oxytetracycline. As an annual industry estimate for all phases, chlortetracycline had the highest estimated use at 533,973 kg. The second and third highest estimates were tylosin and oxytetracycline with estimated annual uses of 165,803 kg and 154,956 kg, respectively. The estimates presented here were constructed to accurately reflect available data related to production practices, and to provide an example of a scientific approach to estimating use of compounds in production animals.

In Vivo Transmission of an IncA/C Plasmid in Escherichia coli Depends on Tetracycline Concentration, and Acquisition of the Plasmid Results in a Variable Cost of Fitness.

Science.gov (United States)

Johnson, Timothy J; Singer, Randall S; Isaacson, Richard E; Danzeisen, Jessica L; Lang, Kevin; Kobluk, Kristi; Rivet, Bernadette; Borewicz, Klaudyna; Frye, Jonathan G; Englen, Mark; Anderson, Janet; Davies, Peter R

2015-05-15

IncA/C plasmids are broad-host-range plasmids enabling multidrug resistance that have emerged worldwide among bacterial pathogens of humans and animals. Although antibiotic usage is suspected to be a driving force in the emergence of such strains, few studies have examined the impact of different types of antibiotic administration on the selection of plasmid-containing multidrug resistant isolates. In this study, chlortetracycline treatment at different concentrations in pig feed was examined for its impact on selection and dissemination of an IncA/C plasmid introduced orally via a commensal Escherichia coli host. Continuous low-dose administration of chlortetracycline at 50 g per ton had no observable impact on the proportions of IncA/C plasmid-containing E. coli from pig feces over the course of 35 days. In contrast, high-dose administration of chlortetracycline at 350 g per ton significantly increased IncA/C plasmid-containing E. coli in pig feces (P IncA/C plasmid to other indigenous E. coli hosts. There was no evidence of conjugal transfer of the IncA/C plasmid to bacterial species other than E. coli. In vitro competition assays demonstrated that bacterial host background substantially impacted the cost of IncA/C plasmid carriage in E. coli and Salmonella. In vitro transfer and selection experiments demonstrated that tetracycline at 32 μg/ml was necessary to enhance IncA/C plasmid conjugative transfer, while subinhibitory concentrations of tetracycline in vitro strongly selected for IncA/C plasmid-containing E. coli. Together, these experiments improve our knowledge on the impact of differing concentrations of tetracycline on the selection of IncA/C-type plasmids. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Transport of Three Antimicrobials in Runoff from Windrows of Composting Beef Cattle Manure.

Science.gov (United States)

Sura, Srinivas; Degenhardt, Dani; Cessna, Allan J; Larney, Francis J; Olson, Andrew F; McAllister, Tim A

2016-03-01

Rain runoff from windrowed or stockpiled manure may contain antimicrobials with the potential to contaminate surface and ground water. To quantify the concentration of antimicrobials transported in runoff from windrowed manure, antimicrobials were administered continuously in feed to beef cattle () as follows: 44 mg of chlortetracycline kg feed (dry weight), a 1:1 mixture of 44 mg of chlortetracycline and 44 mg sulfamethazine kg feed, and 11 mg of tylosin kg feed. Cattle in a fourth treatment group received no antimicrobials (control). Manure from the cattle was used to construct two windrows per treatment. On Days 2 and 21 of composting, a portable Guelph Rainfall Simulator II was used to apply deionized water at an intensity of 127 mm h to each windrow, and the runoff was collected. Manure samples were collected before rain simulations on Days 2 and 21 of composting for antimicrobial analysis. On Day 2, average concentrations of chlortetracycline, sulfamethazine, and tylosin in manure were 2580, 450, and 120 μg kg, respectively, with maximum concentrations in runoff of 2740, 3600, and 4930 μg L, respectively. Concentrations of all three antimicrobials in runoff were higher ( runoff from a windrow (3 m long, 2.5 m wide, 1.5 m high) were approximately 0.87 to 0.94, 1.57, and 1.23 g, respectively. This study demonstrates the importance of windrow composting in reducing antimicrobial concentrations in manure. The runoff from windrows can be a source of antimicrobials and demonstrates the need for containment of runoff from composting facilities to mitigate antimicrobial contamination of surface and groundwater resources. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The effect of the administration of three different antimicrobial premix formulations via the liquid feeding system on the occurrence of Enterobacteriaceae resistant to tetracycline in the liquid feed for pigs.

Science.gov (United States)

Heller, O; Sidler, X; Hässig, M; Thanner, S; Bee, G; Gutzwiller, A; Stephan, R

2016-06-01

The oral group treatment is still a common procedure in swine production. This project studied the effect of the application of 3 different formulations of antimicrobial premixes (1. chlortetracycline, 2. chlortetracycline + sulfadimidine + tylosin, 3. sulfadimidine + sulfathiazole + trimethoprim) via the liquid feeding system on the occurrence of tetracycline-resistant Enterobacteriaceae (Ent-Tetr) in the liquid feed. 156 and 112 feed samples were collected between April and December 2015 in 13 case and 14 control farms, respectively. The 27 farms were randomly selected pig fattening farms located in different parts of Switzerland. The number of feed samples that contained Ent-Tetr as well as the number of Enterobacteriaceae resistant to tetracycline per sample was significantly higher in the case group than in the control group. The use of any of the 3 antimicrobial combinations turned out to be the main risk factor for the occurrence of Ent-Tetr in the liquid feed. Our results suggest that liquid feed containing antimicrobials is a reservoir of antimicrobial resistant bacteria in swine production.

A Confirmatory Method Based on HPLC-MS/MS for the Detection and Quantification of Residue of Tetracyclines in Nonmedicated Feed

Directory of Open Access Journals (Sweden)

Rosa E. Gavilán

2016-01-01

Full Text Available The Commission Regulation 574/2011/EC set up maximum levels of coccidiostats and histomonostats in nonmedicated feed as a consequence of carry-over during manufacturing. Carry-over takes place from medicated to nonmedicated feed during feed production. Similar contamination could also occur for other pharmaceuticals such as tetracyclines, a group of antibiotics commonly employed in food production animal. The objective of this work is to present a simple and fast method for the simultaneous detection of four tetracyclines (chlortetracycline, doxycycline, oxytetracycline, and tetracycline in nontarget feed at a μg/kg level. Validation of the method was performed according to the guideline included in the Commission Decision 2002/657/EC for official method. The validated method was successfully applied to 50 feed samples collected from different milk farms and 25 samples obtained from feed manufacturers. While oxytetracycline was the tetracycline most frequently detected, chlortetracycline was the analyte measured at the highest concentration 15.14 mg/Kg. From 75 nonmedicated feed analysed 15% resulted to be positive for the presence of one tetracycline.

Liquid chromatography – tandem mass spectrometry method for the determination of ten tetracycline residues in muscle samples

Directory of Open Access Journals (Sweden)

Gajda Anna

2015-09-01

Full Text Available A liquid chromatography – tandem mass spectrometry (LC-MS/MS method for the determination of oxytetracycline (OTC, 4-epi oxytetracycline (4-epi OTC, tetracycline (TC, 4-epi tetracycline (4-epi TC, chlortetracycline (CTC, 4-epi chlortetracycline (4-epi CTC, doxycycline (DC, minocycline (MINO, methacycline (META and rolitetracycline (ROLI residues in muscles was developed. The procedure consisted of an oxalic acid extraction followed by protein removal with trichloroacetic acid. Further solid phase clean-up on polymeric (Strata X reversed phase columns was performed to obtain an extract suitable for LC-MS/MS analysis. The tetracyclines were separated on a C 18 analytical column with mobile phase consisting of 0.01% formic acid in acetonitrile and 0.01% formic acid in water in gradient mode. The method was validated according to the Commission Decision 2002/657/EC. The recoveries of all target compounds were 91.8% – 103.6%. The decision limits were from 109.0 to 119.8 μg/kg and detection capability varied within the range of 122.2 to 137.6 μg/kg, depending on the analyte.

Environmental monitoring study of selected veterinary antibiotics in animal manure and soils in Austria

International Nuclear Information System (INIS)

Martinez-Carballo, Elena; Gonzalez-Barreiro, Carmen; Scharf, Sigrid; Gans, Oliver

2007-01-01

LC-MS/MS was used for determination of selected tetracyclines, sulfonamides, trimethoprim, and fluoroquinolones in manure samples of pig, chicken and turkey, as well as arable soils fertilized with manure. Recoveries from spiked samples ranged from 61 to 105%. Method quantification limits were set to 100 μg/kg for all substances. Analysis of 30 pig manure, 20 chicken and turkey dung, and 30 lyophilized soil samples taken in Austria revealed that in pig manure up to 46 mg/kg chlortetracycline, 29 mg/kg oxytetracycline and 23 mg/kg tetracycline could be detected. As representatives of the group of sulfonamides, sulfadimidine in pig manure and sulfadiazine in chicken and turkey dung were detected in significant amounts (maximum concentration, 20 and 91 mg/kg, respectively). Enrofloxacin was particularly observed in chicken and turkey samples. Positive detection of chlortetracycline, enrofloxacin, and ciprofloxacin, in soil samples should be outlined as most important results of this study. - Specific exposure data of selected veterinarian antibiotics in manure and samples of agriculturally used soils are reported for the first time in Austria

Environmental monitoring study of selected veterinary antibiotics in animal manure and soils in Austria

Energy Technology Data Exchange (ETDEWEB)

Martinez-Carballo, Elena [Department of Hazardous Substances and Metabolites, Umweltbundesamt GmbH - Austrian Federal Environment Agency, Spittelauer Laende 5, A-1090 Vienna (Austria); Gonzalez-Barreiro, Carmen [Department of Hazardous Substances and Metabolites, Umweltbundesamt GmbH - Austrian Federal Environment Agency, Spittelauer Laende 5, A-1090 Vienna (Austria); Scharf, Sigrid [Department of Hazardous Substances and Metabolites, Umweltbundesamt GmbH - Austrian Federal Environment Agency, Spittelauer Laende 5, A-1090 Vienna (Austria); Gans, Oliver [Department of Hazardous Substances and Metabolites, Umweltbundesamt GmbH - Austrian Federal Environment Agency, Spittelauer Laende 5, A-1090 Vienna (Austria)

2007-07-15

LC-MS/MS was used for determination of selected tetracyclines, sulfonamides, trimethoprim, and fluoroquinolones in manure samples of pig, chicken and turkey, as well as arable soils fertilized with manure. Recoveries from spiked samples ranged from 61 to 105%. Method quantification limits were set to 100 {mu}g/kg for all substances. Analysis of 30 pig manure, 20 chicken and turkey dung, and 30 lyophilized soil samples taken in Austria revealed that in pig manure up to 46 mg/kg chlortetracycline, 29 mg/kg oxytetracycline and 23 mg/kg tetracycline could be detected. As representatives of the group of sulfonamides, sulfadimidine in pig manure and sulfadiazine in chicken and turkey dung were detected in significant amounts (maximum concentration, 20 and 91 mg/kg, respectively). Enrofloxacin was particularly observed in chicken and turkey samples. Positive detection of chlortetracycline, enrofloxacin, and ciprofloxacin, in soil samples should be outlined as most important results of this study. - Specific exposure data of selected veterinarian antibiotics in manure and samples of agriculturally used soils are reported for the first time in Austria.

Intensification of alcoholic fermentation by the use of antibiotics

Energy Technology Data Exchange (ETDEWEB)

Majchrzak, R; Grzbowski, R; Lacisz, M; Truszczynski, T

1971-01-01

Oxytetracycline and chlortetracycline were used as inhibitors of growth of harmful microflora and as stimulators of yeast growth at a distillery. Oxytetracycline (0.25 to 0.40 units/ml) increased the yield of yeast by 10 to 30% and the yield of ethanol by 10%. The use of antibiotics also improved the fodder properties and stability of potato stillage.

21 CFR 558.195 - Decoquinate.

Science.gov (United States)

2010-04-01

... breeder chickens. Use as sole source of organic arsenic. Poultry should have access to drinking water at... supplements as a top dress or mix into the daily ration to provide 22.7 mg per 100 lb of body weight (0.5 mg... chlortetracycline. Feed Type C medicated feed supplements as a top dress or mix into the daily ration to provide 22...

Effect of Antimicrobial Dosage Regimen on Salmonella and Escherichia coli Isolates from Feeder Swine▿

Science.gov (United States)

Wagner, Bruce A.; Straw, Barbara E.; Fedorka-Cray, Paula J.; Dargatz, David A.

2008-01-01

A body of evidence exists that suggests that antimicrobial use in food animals leads to resistance in both pathogenic and commensal bacteria. This study focused on the impact of three different antimicrobial regimes (low-level continuous, pulse, and no antimicrobial) for two antimicrobials (chlortetracycline and tylosin) on the presence of Salmonella spp. and on the prevalence of antimicrobial resistance of both Salmonella spp. and nonspecific Escherichia coli in fecal samples from feeder swine. The prevalence of fecal samples positive for Salmonella spp. significantly decreased between the samples taken at feeder placement compared to samples taken when the animals were close to market weight. Differences in resistance of Salmonella spp. did not appear to be influenced by dosing treatment including the control. Analysis of antimicrobial resistance examining both susceptibility and resistance, as well as MIC outcomes, demonstrated that only resistance to cephalothin increased in E. coli under the pulse chlortetracycline treatment. These results suggest that the dosing regimes examined in this study did not lead to an increase in either the prevalence of Salmonella spp. or the prevalence of antimicrobial resistance in isolates of Salmonella spp. or E. coli. PMID:18223115

Spread of tetracycline resistance genes at a conventional dairy farm

Czech Academy of Sciences Publication Activity Database

Kyselková, Martina; Jirout, Jiří; Vrchotová, Naděžda; Schmitt, H.; Elhottová, Dana

2015-01-01

Roč. 6, may (2015), s. 536 ISSN 1664-302X R&D Projects: GA ČR GAP504/10/2077; GA MŠk(CZ) EE2.3.30.0032; GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 ; RVO:60077344 Keywords : antibiotic resistance spread * animal manure * cattle intestinal microflora * chlortetracycline * dairy cattle * dairy farm * heavy metals * tetracycline resistance genes Subject RIV: EI - Biotechnology ; Bionics; EE - Microbiology, Virology (BC-A) Impact factor: 4.165, year: 2015

Optimalizace HPLC metody pro separaci tetracyklinových antibiotik

OpenAIRE

Kučerová, Gabriela

2011-01-01

The aim of this work is to develop and to optimize HPLC method for separation of a set of four tetracycline antibiotics - tetracycline, chlortetracycline, oxytetracycline, and doxycycline. Four different reversed octadecyl-silica stationary phases in various mobile phase compositions were examined in isocratic elution. The baseline resolution of all the analytes was obtained by using two columns - Astec C18 and Atlantis C18 I. The optimized separation system consisted of Atlantis C18 I. colum...

Radiation syntheses of Pectin/acrylamide (PEC/PAM) and Pectin/Diethylaminoethylmethacrylate (PEC/DEAMA) hydrogels as drug delivery systems

International Nuclear Information System (INIS)

Abou El Fadl, F.I.; Maziad, N.A.

2015-01-01

Different pH responsive copolymer hydrogels based on pectin were prepared by the effect of radiation. The physical and chemical properties of prepared hydrogels were studied by FTIR, and TGA. Also, the prepared hydrogels were evaluated for the possible use as drug delivery system for chlortetracycline HCL as model drug. The results revealed that the swelling ratios and the release behavior of hydrogels depend mainly on the pH of the medium and the hydrogel composition. (author)

Magnetic solid-phase extraction of tetracyclines using ferrous oxide coated magnetic silica microspheres from water samples.

Science.gov (United States)

Lian, Lili; Lv, Jinyi; Wang, Xiyue; Lou, Dawei

2018-01-26

A novel magnetic solid-phase extraction approach was proposed for extraction of potential residues of tetracyclines (TCs) in tap and river water samples, based on Fe 3 O 4 @SiO 2 @FeO magnetic nanocomposite. Characterized results showed that the received Fe 3 O 4 @SiO 2 @FeO had distinguished magnetism and core-shell structure. Modified FeO nanoparticles with an ∼5 nm size distribution were homogeneously dispersed on the surface of the silica shell. Owing to the strong surface affinity of Fe (II) toward TCs, the magnetic nanocomposite could be applied to efficiently extract three TCs antibiotics, namely, oxytetracycline, tetracycline and chlortetracycline from water samples. Several factors, such as sorbent amount, pH condition, adsorption and desorption time, desorption solvent, selectivity and sample volume, influencing the extraction performance of TCs were investigated and optimized. The developed method showed excellent linearity (R > 0.9992) in the range of 0.133-333 μg L -1 , under optimized conditions. The limits of detection were between 0.027 and 0.107 μg L -1 for oxytetracycline, tetracycline and chlortetracycline, respectively. The feasibility of this method was evaluated by analysis of tap and river water samples. The recoveries at the spiked concentration levels ranged from 91.0% to 104.6% with favorable reproducibility (RSD < 4%). Copyright © 2017 Elsevier B.V. All rights reserved.

Feed Supplementation with Red Seaweeds, Chondrus crispus and Sarcodiotheca gaudichaudii, Reduce Salmonella Enteritidis in Laying Hens

Science.gov (United States)

Kulshreshtha, Garima; Rathgeber, Bruce; MacIsaac, Janice; Boulianne, Martine; Brigitte, Lehoux; Stratton, Glenn; Thomas, Nikhil A.; Critchley, Alan T.; Hafting, Jeff; Prithiviraj, Balakrishnan

2017-01-01

Salmonella Enteritidis is vertically transmitted to eggs from laying hens through infected ovaries and oviducts. S. Enteritidis can also penetrate the eggshell from contaminated feces. Reducing S. Enteritidis in laying hens is vital to provide safer eggs and minimize the spread of salmonellosis to humans. Antibiotics have been widely used to control bacterial diseases in broilers and laying hens. However, there is a major concern that the use of antibiotics leads to the development of antibiotic resistance and adverse effects on microbiota of the treated birds. Thus, there is an interest in developing alternatives to antibiotics, such as dietary prebiotics. In the present study, feed supplemented with the red seaweeds: Chondrus crispus (CC) or Sarcodiotheca gaudichaudii (SG), was offered to laying hens late in production to control S. Enteritidis. Diets contained one of the following; 2% or 4% Chondrus crispus (CC2, and CC4, respectively) or Sarcodiotheca gaudichaudii (SG2 and SG4, respectively). Chlortetracycline was used in the positive control diet. During week-4, 48 birds were orally challenged with 2 × 109 CFU/mL of S. Enteritidis. Eggs and fecal samples were collected 1, 3, 5, and 7 days’ post inoculation. Birds were euthanized and organs (ceca, ovary, liver, and spleen) were sampled and analyzed for the presence of S. Enteritidis, 7 days’ post inoculation. Results showed that seaweed reduced the negative effect on body weight and egg production in S. Enteritidis-challenged laying hens. Analysis of fecal samples showed that the antibiotic (CTC) reduced S. Enteritidis in the intestinal tract and fecal samples, 3 days’ post inoculation. Fecal samples from Chlortetracycline and CC4 supplemented birds tested negative for S. Enteritidis on days 5 and 7 post inoculation (lowest detection limit = 10-1). S. Enteritidis colonization in the ceca was also significantly reduced in birds fed CC (4%) and Chlortetracycline. Blood serum profiles revealed that there

Feed Supplementation with Red Seaweeds, Chondrus crispus and Sarcodiotheca gaudichaudii, Reduce Salmonella Enteritidis in Laying Hens.

Science.gov (United States)

Kulshreshtha, Garima; Rathgeber, Bruce; MacIsaac, Janice; Boulianne, Martine; Brigitte, Lehoux; Stratton, Glenn; Thomas, Nikhil A; Critchley, Alan T; Hafting, Jeff; Prithiviraj, Balakrishnan

2017-01-01

Salmonella Enteritidis is vertically transmitted to eggs from laying hens through infected ovaries and oviducts. S. Enteritidis can also penetrate the eggshell from contaminated feces. Reducing S. Enteritidis in laying hens is vital to provide safer eggs and minimize the spread of salmonellosis to humans. Antibiotics have been widely used to control bacterial diseases in broilers and laying hens. However, there is a major concern that the use of antibiotics leads to the development of antibiotic resistance and adverse effects on microbiota of the treated birds. Thus, there is an interest in developing alternatives to antibiotics, such as dietary prebiotics. In the present study, feed supplemented with the red seaweeds: Chondrus crispus (CC) or Sarcodiotheca gaudichaudii (SG), was offered to laying hens late in production to control S. Enteritidis. Diets contained one of the following; 2% or 4% Chondrus crispus (CC2, and CC4, respectively) or Sarcodiotheca gaudichaudii (SG2 and SG4, respectively). Chlortetracycline was used in the positive control diet. During week-4, 48 birds were orally challenged with 2 × 10 9 CFU/mL of S. Enteritidis. Eggs and fecal samples were collected 1, 3, 5, and 7 days' post inoculation. Birds were euthanized and organs (ceca, ovary, liver, and spleen) were sampled and analyzed for the presence of S. Enteritidis, 7 days' post inoculation. Results showed that seaweed reduced the negative effect on body weight and egg production in S. Enteritidis-challenged laying hens. Analysis of fecal samples showed that the antibiotic (CTC) reduced S. Enteritidis in the intestinal tract and fecal samples, 3 days' post inoculation. Fecal samples from Chlortetracycline and CC4 supplemented birds tested negative for S. Enteritidis on days 5 and 7 post inoculation (lowest detection limit = 10 -1 ). S. Enteritidis colonization in the ceca was also significantly reduced in birds fed CC (4%) and Chlortetracycline. Blood serum profiles revealed that there were

Change in antimicrobial susceptibility of Mycoplasma gallisepticum field isolates.

Science.gov (United States)

Gharaibeh, Saad; Al-Rashdan, Mohammad

2011-06-02

This study compares the antimicrobial susceptibility over time between two groups of Mycoplasma gallisepticum (MG) isolates from the same geographical area. Minimum inhibitory concentration of 13 antimicrobials was determined against two groups of MG isolates from chickens. Group 1 strains (n=22) were isolated in 2004-2005 while group 2 strains (n=7) were isolated in 2007-2008. Minimum inhibitory concentration 50 for group 1 versus group 2 was 4/4, 0.5/0.5, ≤ 0.031/≥ 64, ≤ 0.031/2, ≤ 0.031/0.125, 1/0.5, 1/1, ≤ 0.031/≤ 0.031, ≤ 0.031/2, ≤ 0.031/2, 1/4, ≤ 0.031/0.062, and 0.062/2 μg/ml against gentamicin, spectinomycin, erythromycin, tilmicosin, tylosin, florfenicol, thiamphenicol, tiamulin, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline, respectively. There was a statistically significant increase in resistance of group 2 to erythromycin, tilmicosin, tylosin, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline. This dramatic increase in resistance against 8 antimicrobials belonging to three different families of antimicrobials in a relatively short period of time appears to be rare and of concern. The cause of this increased resistance observed in group 2 of MG isolates was not determined and should be further investigated. Monitoring of MG field strain susceptibility is highly recommended to implement successful treatment and prophylaxis programs in endemic areas. Copyright © 2011 Elsevier B.V. All rights reserved.

Synthesis and Characterization of Super absorbent Hydrogels Based on Natural Polymers Using Ionizing Radiations

International Nuclear Information System (INIS)

Deghiedy, N.M.A.

2010-01-01

Radiation processing technology is a useful tool for modification of polymer material including grafting of monomer onto polymer. In this study, novel super absorbent hydrogels was prepared with biodegradable and eco-friendly properties by graft copolymerization of chitosan and different synthetic monomers (AAc, DEAEMA, HEMA, HPMA and HEA) using gamma irradiation to examine the potential use of these hydrogels in the controlled drug release systems. The different chitosan hydrogels were characterized using FTIR spectroscopy, scanning electron microscopy and thermal analysis techniques. The effects of the preparation conditions on the gelation process of the synthesized copolymer were investigated. The influence of variables such as feed concentration, irradiation dose, composition ratio, ph and temperature on the swelling of the prepared hydrogels was also examined. The water absorbency of these hydrogels in various ph and salt solutions was studied. The swelling kinetics of the prepared hydrogels and in vitro release dynamics of model drug (Chlortetracycline hydrochloride) from these hydrogels has been studied for the evaluation of swelling mechanism and drug release mechanism from the hydrogels. The adsorption and in vitro release profiles of Chlortetracycline HCl from the prepared gels were also estimated in different ph buffers. The amount of drug released from CS/ (AAc-DEAEMA) hydrogels was higher than that released from other modified CS/AAc hydrogels. This preliminary investigation of chitosan based hydrogels showed that they may be exploited to expand the utilization of these systems in drug delivery applications

Standardized method to produce tetracycline-stained human molar teeth in vitro.

Science.gov (United States)

Chan, Daniel C N; Rozier, Gregory Shayne; Steen, Angela; Browning, William D; Mozaffari, Mahmood S

2006-09-01

This study tested the hypothesis that exposure of human molar teeth to tetracycline (TCN) derivatives in vitro results in tooth discoloration resembling the clinical presentation of TCN staining. The effects of exposure of 20 extracted human molar teeth to distilled water, chlortetracycline, doxycycline, or minocycline were compared. The baseline color of each tooth was analyzed with a dental spectrophotometer. The pulp chambers were each filled with a TCN derivative solution and then sealed. The teeth were placed in a centrifuge tube and then centrifuged at 2800 rpm for 20 minutes. Color change was monitored weekly for 7 weeks. Digital images of the surfaces were recorded. For each specimen at every evaluation period, color change from baseline was calculated using Commission Internationale d'Eclairage (CIE) Delta E 2000 (deltae00). There was a significant association between the type of derivative used and deltae00, as well as between the evaluation period and deltae00. There was also a significant association between the interaction term, derivative x evaluation period, and deltae00. Results of the Holm-Sidak post hoc test demonstrated that all 3 TCN derivatives were associated with significantly larger deltae00 than the control group (P < or = .05). All 3 TCN derivative solutions produced significant color changes as time progressed. Different TCN derivatives produced a different L* (lightness), C* (chroma), and H* (hue), with minocycline behaving distinctly differently from chlortetracycline and doxycycline. The model could be used to study the underlying mechanisms of TCN staining as well as many aspects of vital tooth

Distribution and ecological risk of antibiotics in a typical effluent-receiving river (Wangyang River) in north China.

Science.gov (United States)

Jiang, Yonghai; Li, Mingxiao; Guo, Changsheng; An, Da; Xu, Jian; Zhang, Yuan; Xi, Beidou

2014-10-01

In this study, the occurrence and distribution of sixteen antibiotics belonging to four groups in surface water, sediment and groundwater samples from the Wangyang River (WYR), a typical river receiving sewage discharges were investigated. Laboratory analyses revealed that antibiotics were widely distributed in the studied area. The aqueous samples were unavoidably contaminated with antibiotics, and the target antibiotics present in high levels were oxytetracycline, tetracycline, chlortetracycline, ofloxacin, sulfamethoxazole, and trimethoprim, with maximum concentrations of the individual contaminant at 3.6×10(5), 9.7×10(3), 6.9×10(4), 1.2×10(4), 4.8×10(3), and 1.1×10(3) ng L(-1), respectively. Oxytetracycline, tetracycline, ciprofloxacin and roxithromycin were the most frequently detected compounds in sediment samples, with maximum concentrations of the individual contaminant at 1.6×10(5), 1.7×10(4), 2.1×10(3) and 2.5×10(3) ng g(-1), respectively. The results also revealed that the high intensity of aquaculture activities could contribute to the increasing levels of antibiotics in the area. According to the ratios of measured environmental concentration (MEC) to predicted no-effect concentration (PNEC), chlortetracycline, tetracycline, ofloxacin, ciprofloxacin, erythromycin-H2O and sulfamethoxazole may present possible environmental risk to Pseudokirchneriella subcapitata, Synechococcus leopoliensis and M. aeruginosa. Attention should be given to the long-term ecological effects caused by the continuous discharge of antibiotics in the WYR area. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial Consumption in Medicated Feeds in Vietnamese Pig and Poultry Production.

Science.gov (United States)

Van Cuong, Nguyen; Nhung, Nguyen Thi; Nghia, Nguyen Huu; Mai Hoa, Nguyen Thi; Trung, Nguyen Vinh; Thwaites, Guy; Carrique-Mas, Juan

2016-09-01

Antimicrobials are extensively used as growth promoters in animal feeds worldwide, but reliable estimates are lacking. We conducted an internet-based survey of commercial chicken and pig feed products officially approved for sale in Vietnam over the period March-June 2015. Information on the antimicrobial contents in feed products, alongside animal production data, was used to estimate in-feed antimicrobial consumption to produce one kilogram of live animal (chicken, pig), as well as to estimate country-wide antimicrobial consumption through animal feeds. A total of 1462 commercial feed formulations were examined. The survey-adjusted estimated antimicrobial contents were 25.7 and 62.3 mg/kg in chicken and pig feeds, respectively. Overall, it was estimated that 77.4 mg [95% CI 48.1-106.8] and 286.6 mg [95% CI 191.6-418.3] of in-feed antimicrobials were used to raise 1 kg of live chicken and pig, respectively. Bacitracin (15.5% feeds), chlortetracycline (11.4%), and enramycin (10.8%) were the most common antimicrobials present in chicken feed formulations, whereas bacitracin (24.8%), chlortetracycline (23.9%), and florfenicol (17.4%) were the most common in pig feed formulations. Overall, 57% of the total quantitative usage consisted of antimicrobials regarded by WHO of importance for human medicine, including amoxicillin, colistin, tetracyclines, neomycin, lincomycin, and bacitracin. These figures confirm a very high magnitude of in-feed consumption of antimicrobials, especially in pig production. Results from this study should encourage further monitoring of antimicrobials used in animal production, and foster discussion about existing policies on inclusion of antimicrobials in animal feed rations.

Susceptibilities of Mycoplasma bovis, Mycoplasma dispar, and Ureaplasma diversum strains to antimicrobial agents in vitro.

Science.gov (United States)

ter Laak, E A; Noordergraaf, J H; Verschure, M H

1993-02-01

The purpose of this study was to determine the susceptibility of various strains of Mycoplasma bovis, Mycoplasma dispar, and Ureaplasma diversum, which are prevalent causes of pneumonia in calves, to 16 antimicrobial agents in vitro. The MICs of the antimicrobial agents were determined by a serial broth dilution method for 16 field strains and the type strain of M. bovis, for 19 field strains and the type strain of M. dispar, and for 17 field strains of U. diversum. Final MICs for M. bovis and M. dispar were read after 7 days and final MICs for U. diversum after 1 to 2 days. All strains tested were susceptible to tylosin, kitasamycin, and tiamulin but were resistant to nifuroquine and streptomycin. Most strains of U. diversum were intermediately susceptible to oxytetracycline but fully susceptible to chlortetracycline; most strains of M. bovis and M. dispar, however, were resistant to both agents. Strains of M. dispar and U. diversum were susceptible to doxycycline and minocycline, but strains of M. bovis were only intermediately susceptible. Susceptibility or resistance to chloramphenicol, spiramycin, spectinomycin, lincomycin, or enrofloxacin depended on the species but was not equal for the three species. The type strains of M. bovis and M. dispar were more susceptible to various antimicrobial agents, including tetracyclines, than the field strains. This finding might indicate that M. bovis and M. dispar strains are becoming resistant to these agents. Antimicrobial agents that are effective in vitro against all three mycoplasma species can be considered for treating mycoplasma infections in pneumonic calves. Therefore, tylosin, kitasamycin, and tiamulin may be preferred over oxytetracycline and chlortetracycline.

Characterization of the europium tetracycline complex as a biomarker for atherosclerosis

Science.gov (United States)

Courrol, Lilia C.; da Silva, Mônica N.; Sicchieri, Leticia B.

2016-04-01

Atherosclerosis is a narrowing of the arteries caused by an increase of atheromatous plaque: material formed by macrophage cells containing cholesterol and fatty acids, calcium and a variable amount of fibrous connective tissue. The elation between vulnerable plaques and cardiovascular events can be determined using plaque biomarkers. In this work, atherosclerotic plaques stained with different molar ratios of europium, in a potential plaque biomarker, europium tetracycline complex, were studied by fluorescence microscopy. The tetracycline antibiotic used was chlortetracycline. The growth of atherosclerotic plaque was followed during 60 days in New Zealand rabbits divided in two groups: an experimental group (EG), with nine animals and a control group (CG) with three animals. The animals in the EG received a diet with 1% of cholesterol and the animals of GC received a normal diet. The aortic arch of the animals with 60 days were cut in the vertical plane in 6 μm thick slices, which were mounted on glass slides and stained with hematoxylin an eosin and europium chlortetracycline complex (EuCTc). The fluorescence images were obtained exciting the EuCTc absorption band with a filter cube D (BP 355 - 425) and the emission was collected with a LP 470 suppression filter. Light intensity, detector gain and acquisition time were fixed for comparisons. The 20× magnified images were collected with 12 bit (or 4096 gray tones) resolution. The mean value of gray scale for each molar ratio of EuCTc was different, indicating that the complex interacts with the components of atherosclerotic plaque and the best molar ratio was 1.5 EuCTc. These results indicate the potential use of the EuCTc biomarker for atherosclerotic plaque characterization.

A study on monitoring of pharmaceuticals and personal care products (PPCPs) in livestock wastewater and treatment by radiation techniques

Energy Technology Data Exchange (ETDEWEB)

Myung, Seung Woon [KAERI, Daejeon (Korea, Republic of)

2010-05-15

In this study, and effective monitoring and the investigation of treatment efficiency of pharmaceuticals from the influent and effluent of livestock wastewater treatment plant (WWTPs) and by-product with radiation processing by LC/ESI-MS/MS was performed. Thirteen pharmaceuticals including antibiotics, growth promoters and disinfectants were assayed from twelve WWTPs in South Korea. The established method could be used to determine low concentration levels of pharmaceuticals in environmental samples. From few influents of live-stock WWTPs, chlortetracycline and acetaminophen were detected with the highest concentration among the monitoring pharmaceuticals. And also lincomycin, sufathiazole, sulfamethazine, trimethoprim, acetyl salicylic acid, tylosin, glutaraldehyde and formaldehyde were detected from the influents of WWTPs

A study on monitoring of pharmaceuticals and personal care products (PPCPs) in livestock wastewater and treatment by radiation techniques

International Nuclear Information System (INIS)

Myung, Seung Woon

2010-05-01

In this study, and effective monitoring and the investigation of treatment efficiency of pharmaceuticals from the influent and effluent of livestock wastewater treatment plant (WWTPs) and by-product with radiation processing by LC/ESI-MS/MS was performed. Thirteen pharmaceuticals including antibiotics, growth promoters and disinfectants were assayed from twelve WWTPs in South Korea. The established method could be used to determine low concentration levels of pharmaceuticals in environmental samples. From few influents of live-stock WWTPs, chlortetracycline and acetaminophen were detected with the highest concentration among the monitoring pharmaceuticals. And also lincomycin, sufathiazole, sulfamethazine, trimethoprim, acetyl salicylic acid, tylosin, glutaraldehyde and formaldehyde were detected from the influents of WWTPs

Magnetic separation of antibiotics by electrochemical magnetic seeding

Energy Technology Data Exchange (ETDEWEB)

Ihara, I; Toyoda, K [Department of Agricultural Engineering and Socio Economics, Kobe University, Nada, Kobe 657-8501 (Japan); Beneragama, N; Umetsu, K [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555 (Japan)

2009-03-01

Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.

Magnetic separation of antibiotics by electrochemical magnetic seeding

International Nuclear Information System (INIS)

Ihara, I; Toyoda, K; Beneragama, N; Umetsu, K

2009-01-01

Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.

Unusual disease conditions in pet and aviary birds.

Science.gov (United States)

Panigrahy, B; Mathewson, J J; Hall, C F; Grumbles, L C

1981-02-15

Ninety percent ot 100% mortality in budgerigar (Melopsittacus undulatus) nestlings from 2 aviaries was attributed to giardiasis. Treatment with dimetridazole in drinking water was effective in controlling mortality. Aeromonas hydrophila infection incriminated in acute deaths of aviary canaries (Serinus canarius) was successfully treated with chlortetracycline. Aeromonas hydrophila also was isolated in pure culture from a toucan (ramphastos toco) with acute nephrosis and a cockatiel (Nymphicus hollandicus) with chlamydiosis (psittacosis). Coccidiosis associated with hemorrhagic enteritis, diarrhea, and mortality was diagnosed in budgerigars originating from 3 aviaries. Sporulated oocysts from 1 group of budgerigars were identified as Eimera sp. Sulfamethazine in drinking water was an effective treatment.

Transport of three veterinary antimicrobials from feedlot pens via simulated rainfall runoff.

Science.gov (United States)

Sura, Srinivas; Degenhardt, Dani; Cessna, Allan J; Larney, Francis J; Olson, Andrew F; McAllister, Tim A

2015-07-15

Veterinary antimicrobials are introduced to wider environments by manure application to agricultural fields or through leaching or runoff from manure storage areas (feedlots, stockpiles, windrows, lagoons). Detected in manure, manure-treated soils, and surface and ground water near intensive cattle feeding operations, there is a concern that environmental contamination by these chemicals may promote the development of antimicrobial resistance in bacteria. Surface runoff and leaching appear to be major transport pathways by which veterinary antimicrobials eventually contaminate surface and ground water, respectively. A study was conducted to investigate the transport of three veterinary antimicrobials (chlortetracycline, sulfamethazine, tylosin), commonly used in beef cattle production, in simulated rainfall runoff from feedlot pens. Mean concentrations of veterinary antimicrobials were 1.4 to 3.5 times higher in surface material from bedding vs. non-bedding pen areas. Runoff rates and volumetric runoff coefficients were similar across all treatments but both were significantly higher from non-bedding (0.53Lmin(-1); 0.27) than bedding areas (0.40Lmin(-1); 0.19). In keeping with concentrations in pen surface material, mean concentrations of veterinary antimicrobials were 1.4 to 2.5 times higher in runoff generated from bedding vs. non-bedding pen areas. Water solubility and sorption coefficient of antimicrobials played a role in their transport in runoff. Estimated amounts of chlortetracycline, sulfamethazine, and tylosin that could potentially be transported to the feedlot catch basin during a one in 100-year precipitation event were 1.3 to 3.6ghead(-1), 1.9ghead(-1), and 0.2ghead(-1), respectively. This study demonstrates the magnitude of veterinary antimicrobial transport in feedlot pen runoff and supports the necessity of catch basins for runoff containment within feedlots. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Residues of veterinary antibiotics in manures from feedlot livestock in eight provinces of China.

Science.gov (United States)

Zhao, Ling; Dong, Yuan Hua; Wang, Hui

2010-02-01

The residue levels of selected fluoroquinolones, sulfonamides and tetracyclines in 143 animal dung samples collected in 2007 from large-scale livestock and poultry feedlots in 8 provinces were determined by using ultrasonic extraction and liquid chromatography. Recoveries from spiked pig dung samples (spike level=1mg/kg) ranged from 73.9 to 102.0% for fluoroquinolones, from 81.6 to 92.3% for sulfonamides, and from 57.2 to 72.6% for tetracyclines. Relative standard deviations of the recoveries were less than 10% within the same day. Method quantification limits were measured from 0.031 to 0.150 mg/kg for fluoroquinolones, from 0.023 to 0.082 mg/kg for sulfonamides, and 0.091 to 0.182 mg/kg for tetracyclines in spiked pig manure samples. Analysis of 61 pig, 54 chicken and 28 cow dung samples collected in China revealed that in pig and cow dung, up to 33.98 and 29.59 mg/kg ciprofloxacin, 33.26 and 46.70 mg/kg enrofloxacin, 59.06 and 59.59 mg/kg oxytetracycline, and 21.06 and 27.59 mg/kg chlortetracycline could be detected, respectively. A maximum concentration of 99.43 mg/kg fleroxacin, 225.45 mg/kg norfloxacin, 45.59 mg/kg ciprofloxacin and 1420.76 mg/kg enrofloxacin could be detected in chicken dung. No appreciable sulfonamide antibiotic concentrations (less than 10mg/kg) were found in any animal dung, and only sulfadimidine was observed, at a maximum concentration of 6.04 mg/kg, in chicken dung. Both enrofloxacin and chlortetracycline were detected with a very high occurrence in three animal manure samples. The residue levels for most antibiotics showed significant statistical differences among the sampling districts and the animal species. Copyright 2009 Elsevier B.V. All rights reserved.

Use patterns, excretion masses and contamination profiles of antibiotics in a typical swine farm, south China.

Science.gov (United States)

Zhou, Li-Jun; Ying, Guang-Guo; Zhang, Rui-Quan; Liu, Shan; Lai, Hua-Jie; Chen, Zhi-Feng; Yang, Bin; Zhao, Jian-Liang

2013-04-01

The objective of this study was to screen the occurrence of 50 antibiotics in a typical swine farm in southern China, which includes animal feeds, waste collection and treatment systems (lagoons and anaerobic digesters), and receiving environments (vegetable fields, streams, and private wells). Nine antibiotics were found in the feeds for different stages of the development of pigs in the swine farm, at concentrations ranging from 2.37 ± 0.16 ng g(-1) (sulfamethazine) to 61 500 ± 11 900 ng g(-1) (bacitracin). 11, 17 and 15 target compounds were detected in feces, flush water, and suspended particles in the swine farm, respectively. Based on the survey of feeds and animal waste from the farm, chlortetracycline, tetracycline, bacitracin and florfenicol in the feces, flush water and suspended particles mainly originated from the feeds, while most sulfonamides, including doxycycline, oxytetracycline, fluoroquinolones, macrolides and trimethoprim, were mainly from injection and other oral routes. The daily excretion masses of antibiotics per pig calculated based on animal waste had the following order: sows (48.3 mg per day per pig), piglets (18.9 mg per day per pig), growing pigs (7.01 mg per day per pig) and finishing pigs (1.47 mg per day per pig), indicating that the usage of antibiotics (type and dosage) and excretion masses are related to the growth stage of pigs. Chlortetracycline and bacitracin are the main contributors to the total excretion mass of antibiotics from pigs at different stages of development in the farm. The waste treatment system (lagoons and anaerobic digesters) was found to be ineffective in the elimination of antibiotics. The detection of some antibiotics in the surrounding environments of the farm (the well water, stream water and vegetable field soil) was a reflection of pollution from the swine farm.

Susceptibility of Haemophilus equigenitalis, the causal agent of contagious equine metritis, to 31 antimicrobial agents.

Science.gov (United States)

Sugimoto, C; Isayama, Y; Kashiwazaki, M; Mitani, K

1981-01-01

The minimal inhibitory concentrations of 31 antimicrobial agents were determined for 99 isolates of Haemophilus equigenitalis by the agar dilution method. All the isolates showed good susceptibility to 26 antimicrobial agents tests, minimal inhibitory concentrations of which were less than 3.13 micrograms/ml for more than 90% of the isolates. Of these agents, 4 macrolides (erythromycin, oleandomycin, kitasamycin, tylosin), 3 tetracyclines (tetracycline, chlortetracycline, oxytetracycline), 1 peptide (colistin), 1 penicillin (ampicillin) and 1 pleuromutilin (tiamulin) were the most active agents, showing a minimal inhibitory concentration of less than 0.39 micrograms/ml for more than 90% of the isolates. The growth of more than 90% of the isolates was not inhibited by 800 micrograms/ml of streptomycin.

Molecular Basis of Resistance to Selected Antimicrobial Agents in the Emerging Zoonotic Pathogen Streptococcus suis.

Science.gov (United States)

Gurung, Mamata; Tamang, Migma Dorji; Moon, Dong Chan; Kim, Su-Ran; Jeong, Jin-Ha; Jang, Geum-Chan; Jung, Suk-Chan; Park, Yong-Ho; Lim, Suk-Kyung

2015-07-01

Characterization of 227 Streptococcus suis strains isolated from pigs during 2010 to 2013 showed high levels of resistance to clindamycin (95.6%), tilmicosin (94.7%), tylosin (93.8%), oxytetracycline (89.4%), chlortetracycline (86.8%), tiamulin (72.7%), neomycin (70.0%), enrofloxacin (56.4%), penicillin (56.4%), ceftiofur (55.9%), and gentamicin (55.1%). Resistance to tetracyclines, macrolides, aminoglycosides, and fluoroquinolone was attributed to the tet gene, erm(B), erm(C), mph(C), and mef(A) and/or mef(E) genes, aph(3')-IIIa and aac(6')-Ie-aph(2″)-Ia genes, and single point mutations in the quinolone resistance-determining region of ParC and GyrA, respectively. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In vitro sensitivities to antimicrobial drugs of ureaplasmas isolated from the bovine respiratory tract, genital tract and eye.

Science.gov (United States)

Kishima, M; Hashimoto, K

1979-09-01

The sensitivity to 18 antimicrobial drugs was examined for 66 strains of Ureaplasma sp isolated from respiratory tracts of calves suffering from enzootic pneumonia, urinary tracts of bulls and eyes of cows suffering from infectious bovine kerato-conjunctivitis. Furamizole, tiamulin fumarate, erythromycin lactobionate, malidomycin C, doxycycline hydrochloride, kitasamycin tartrate, tylosin tartrate, T-2636C, tetracycline hydrochloride, oxytetracycline hydrochloride, chlortetracycline hydrochloride, oleandomycin phosphate, furazolidone, spiramycin adipate, chloramphenicol and thiophenicol showed strong inhibiting activity on all the test strains. Among them, furamizole, tiamulin fumarate and erythromycin lactobionate were most active. Kanamycin sulphate showed weak activity on all the strains tested. The differences in origin of the test strains did not affect their sensitivity to any of the drugs.

Quantification of bioavailable chlortetracycline in pig feces using a bacterial whole-cell biosensor

DEFF Research Database (Denmark)

Hansen, L. H.; Aarestrup, Frank Møller; Sørensen, S. J.

2002-01-01

and maintenance of fecal coliform bacteria resistant to tetracycline. Initially, large quantities of water-extractable CTC were excreted from the pigs and measurable amounts were detected even at 30 days after treatment cessation. This led to a sharp rise in the number of tetracycline resistant coliform bacteria...... in the feces, to within the same order of magnitude as the total coliform count. The high level of tetracycline resistance was maintained in spite of the declining concentration of tetracycline. (C) 2002 Elsevier Science B.V. All rights reserved....

Effects of anaerobic digestion on chlortetracycline and oxytetracycline degradation efficiency for swine manure.

Science.gov (United States)

Yin, Fubin; Dong, Hongmin; Ji, Chao; Tao, Xiuping; Chen, Yongxing

2016-10-01

Manure containing antibiotics is considered a hazardous substance that poses a serious health risk to the environment and to human health. Anaerobic digestion (AD) could not only treatment animal waste but also generate valuable biogas. However, the interaction between antibiotics in manure and the AD process has not been clearly understood. In this study, experiments on biochemical methane potential (BMP) were conducted to determine the inhibition of the AD process from antibiotics and the threshold of complete antibiotic removal. The thresholds of the complete antibiotic removal were 60 and 40mg/kg·TS for CTC and OTC, respectively. CTC and OTC with concentrations below thresholds could increase the BMP of manure. When the CTC and OTC concentrations exceeded the thresholds, they inhibited manure fermentation, and the CTC removal rate declined exponentially with concentration (60-500mg/kg·TS). The relationship between OTC antibiotic concentration and its removal rate in AD treatment was described with exponential (40-100mg/kg·TS) and linear equations (100-500mg/kg·TS). Copyright © 2016 Elsevier Ltd. All rights reserved.

Hierarchical La0.7Ce0.3FeO3/halloysite nanocomposite for photocatalytic degradation of antibiotics

Science.gov (United States)

Li, Xiazhang; Zhu, Wei; Yan, Xiangyu; Lu, Xiaowang; Yao, Chao; Ni, Chaoying

2016-08-01

The hierarchical La0.7Ce0.3FeO3/halloysite nanotubes (HNTs) composites have been successfully prepared via sol-gel method. XRD and TEM characterizations indicated that the sheet-like La0.7Ce0.3FeO3 coupled with the co-precipitated CeO2 were evenly deposited onto the surface of halloysite. The photocatalytic degradation of chlortetracycline under visible light irradiation using La0.7Ce0.3FeO3/HNTs as catalyst was evaluated by high-performance liquid chromatography, which exhibited remarkable photocatalytic activity with the removal rate up to 99 % in 90 min, due to the formation of "solid solution/co-precipitation" heterostructure as well as the excellent adsorptive capability of halloysite for antibiotics.

Hierarchical La0.7Ce0.3FeO3/halloysite nanocomposite for photocatalytic degradation of antibiotics

International Nuclear Information System (INIS)

Li, Xiazhang; Yao, Chao; Zhu, Wei; Yan, Xiangyu; Lu, Xiaowang; Ni, Chaoying

2016-01-01

The hierarchical La 0.7 Ce 0.3 FeO 3 /halloysite nanotubes (HNTs) composites have been successfully prepared via sol-gel method. XRD and TEM characterizations indicated that the sheet-like La 0.7 Ce 0.3 FeO 3 coupled with the co-precipitated CeO 2 were evenly deposited onto the surface of halloysite. The photocatalytic degradation of chlortetracycline under visible light irradiation using La 0.7 Ce 0.3 FeO 3 /HNTs as catalyst was evaluated by high-performance liquid chromatography, which exhibited remarkable photocatalytic activity with the removal rate up to 99 % in 90 min, due to the formation of ''solid solution/co-precipitation'' heterostructure as well as the excellent adsorptive capability of halloysite for antibiotics. (orig.)

Photocatalytic degradation of tetracycline by Ti-MCM-41 prepared at room temperature and biotoxicity of degradation products

Science.gov (United States)

Zhou, Kefu; Xie, Xiao-Dan; Chang, Chang-Tang

2017-09-01

Ti-doped MCM-41 with different Si/Ti molar ratios was prepared at room temperature to degrade tetracycline antibiotics in aqueous solution. The Ti was doped into the skeleton structure of MCM-41. The photocatalytic activity of Ti-doped MCM-41 was investigated. The optimal catalyst had Si/Ti molar ratio of 25 and over 99% removal of oxytetracycline in 150 min, and the removal could maintain 98% after 5 reuses. Ions and soluble organic matters in natural water affected the degradation reaction when Ti-doped MCM-41 was used to treat simulated wastewater of chicken farms. The degradation products of oxytetracycline, tetracycline and chlortetracycline were detected by Escherichia coli DH5α and HPLC-MS/MS. No intermediate product with higher toxicity was detected.

Chemiluminescence determination of tetracyclines using Fenton system in the presence europium(III) ions

International Nuclear Information System (INIS)

Kaczmarek, Malgorzata; Lis, Stefan

2009-01-01

A new simple chemiluminescent method for the determination of chlortetracycline (Chlor-TC), oxytetracycline (Oxy-TC) and doxycycline (Doxy-TC) is described. This method is based on the europium(III) emission as a result of the energy transfer process from the excited product of the tetracyclines oxidation to the uncomplexed Eu(III). Under the optimum conditions, calibration graphs were obtained for 4 x 10 -7 to 2 x 10 -5 mol L -1 of Chlor-TC; 2 x 10 -7 to 2 x 10 -5 mol L -1 of Oxy-TC and 1 x 10 -7 to 3 x 10 -5 mol L -1 of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

[Effects of antimicrobial drugs on soil microbial respiration].

Science.gov (United States)

Liu, Feng; Ying, Guang-Guo; Zhou, Qi-Xing; Tao, Ran; Su, Hao-Chang; Li, Xu

2009-05-15

The effects on soil microbial respiration of sulfonamides, tetracyclines, macrolides and so on were studied using the direct absorption method. The results show sulfamethazine, sulfamethoxazole, chlortetracycline, tetracycline, tylosin and trimethoprim inhibit soil respiration 34.33%, 34.43%, 2.71%, 3.08%, 7.13%, 38.08% respectively. Sulfamethoxazole and trimethoprim have the highest inhibition rates among all the antibiotics. In early incubation period (0-2 d), the concentrations above 10 mg x kg(-1) of sulfamethazine, sulfamethoxazole and trimethoprim remarkably decrease soil CO2 emission. The effects of these antibiotics vary with their concentrations too. Sulfamethoxazole and trimethoprim show good dose-response relationships. According to the standard of pesticide safety evaluation protocol, the six antibiotics pose a little risk to soil microbial environment.

Implementation of the Bacillus cereus microbiological plate used for the screening of tetracyclines in raw milk samples with STAR protocol - the problem with false-negative results solved.

Science.gov (United States)

Raspor Lainšček, P; Biasizzo, M; Henigman, U; Dolenc, J; Kirbiš, A

2014-01-01

In antibiotic residue analyses the first step of screening is just as important as the following steps. Screening methods need to be quick and inexpensive, but above all sensitive enough to detect the antibiotic residue at or below the maximum residue limit (MRL). In the case of a positive result, the next step is conducted and further methods are used for confirmation. MRLs stated in European Union Regulation 37/2010 for tetracyclines in raw milk are: 100 µg kg(-1) for tetracycline, 100 µg kg(-1) for oxytetracycline, 100 µg kg(-1) for chlortetracycline and no limit for doxycycline because it is prohibited for use in animals from which milk is produced for human consumption. The current five-plate microbiological screening method for the detection of antibiotic residues in raw milk was found to be simple and inexpensive, but not specific, sensitive and reliable enough to detect tetracycline at MRL in routine raw milk screening procedures. Spiking samples with tetracycline at the MRL level and applying them on Bacillus cereus ATCC 11778 microbiological plates often gave false-negative results, indicating that tetracyclines may have to be inactivated or masked. Tetracyclines seem to bind to a certain component in milk. Consequently, when applying samples to the B. cereus microbiological plate the antibiotic cannot inhibit the growth of B. cereus which disables the formation of inhibition zones on the test plate. After adding the appropriate amount of citric acid into the milk samples, we solved the problem of false-negative results. During the validation 79 samples of milk were spiked with tetracyclines at different concentrations: 100 µg kg(-1) for tetracycline, 100 µg kg(-1) for oxytetracycline, 80 µg kg(-1) for chlortetracycline and 30 µg kg(-1) for doxycycline. Concentrations used in the validation matched the requirements for MRLs (they were either at or below the MRLs) stated in European Union Regulation 37/2010. The sensitivity of the validation was 100%.

Probabilistic risk model to assess the potential for resistance selection following the use of anti-microbial medicated feed in pigs.

Science.gov (United States)

Filippitzi, Maria Eleni; Chantziaras, Ilias; Devreese, Mathias; Dewulf, Jeroen

2018-05-30

The cross-contamination of non-medicated feed with residues of anti-microbials (AM) causes a public and animal health concern associated with the potential for selection and dissemination of resistance. To analyse the associated risks, a probabilistic model was built using @Risk® (Palisade Corporation®) to show the potential extent of the effect of cross-contaminated pig feed on resistance selection. The results of the model include estimations of the proportion of pigs per production stage with residues of doxycycline, chlortetracycline, sulfadiazine and trimethoprim in their intestinal contents, as a result of exposure to cross-contaminated feed with different carry-over levels, in Belgium. By using a semi-quantitative approach, these estimations were combined with experimental data on AM concentrations associated with potential for resistance-selection pressure. Based on this model, it is estimated that 7.76% (min = 1.67; max = 36.94) of sows, 4.23% (min = 1.01%; max = 18.78%) of piglets and 2.8% (min = 0.51%; max = 14.9%) of fatteners in Belgium have residues of doxycycline in their intestinal tract due to consumption of feed with at least 1% carry-over. These values were estimated to be almost triple for sulfadiazine, but substantially lower for chlortetracycline and trimethoprim. Doxycycline concentrations as low as 1 mg/L (corresponding to consumed feed with at least 1% carry-over) can select for resistant porcine commensal Escherichia coli in vitro and in vivo. Conclusions on this risk could not be drawn for other AM at this stage, due to the lack of data on concentrations associated with resistance development. However, since the possibility of resistance mechanisms (e.g. co-selection) occurring cannot be excluded, the results of this model highlight that the use of AM medicated feed should be minimised where possible. In case of medicated feed production, good practice should be followed thoroughly at all levels of production, distribution

Distribution and characterization of ampicillin- and tetracycline-resistant Escherichia coli from feedlot cattle fed subtherapeutic antimicrobials

Directory of Open Access Journals (Sweden)

Yanke L Jay

2011-04-01

Full Text Available Abstract Background Feedlot cattle in North America are routinely fed subtherapeutic levels of antimicrobials to prevent disease and improve the efficiency of growth. This practice has been shown to promote antimicrobial resistance (AMR in subpopulations of intestinal microflora including Escherichia coli. To date, studies of AMR in feedlot production settings have rarely employed selective isolation, therefore yielding too few AMR isolates to enable characterization of the emergence and nature of AMR in E. coli as an indicator bacterium. E. coli isolates (n = 531 were recovered from 140 cattle that were housed (10 animals/pen in 14 pens and received no dietary antimicrobials (control - 5 pens, CON, or were intermittently administered subtherapeutic levels of chlortetracycline (5 pens-T, chlortetracycline + sulfamethazine (4 pens-TS, or virginiamycin (5 pens-V for two separate periods over a 9-month feeding period. Phenotype and genotype of the isolates were determined by susceptibility testing and pulsed field gel electrophoresis and distribution of characterized isolates among housed cattle reported. It was hypothesized that the feeding of subtherapeutic antibiotics would increase the isolation of distinct genotypes of AMR E. coli from cattle. Results Overall, patterns of antimicrobial resistance expressed by E. coli isolates did not change among diet groups (CON vs. antibiotic treatments, however; isolates obtained on selective plates (i.e., MA,MT, exhibited multi-resistance to sulfamethoxazole and chloramphenicol more frequently when obtained from TS-fed steers than from other treatments. Antibiograms and PFGE patterns suggested that AMR E. coli were readily transferred among steers within pens. Most MT isolates possessed the tet(B efflux gene (58.2, 53.5, 40.8, and 50.6% of isolates from CON, T, TS, and V steers, respectively whereas among the MA (ampicillin-resistant isolates, the tem1-like determinant was predominant (occurring in 50, 66

Effects of ionophores and antibiotics on in vitro hydrogen sulfide production, dry matter disappearance, and total gas production in cultures with a steam-flaked corn-based substrate with or without added sulfur.

Science.gov (United States)

Quinn, M J; May, M L; Hales, K E; DiLorenzo, N; Leibovich, J; Smith, D R; Galyean, M L

2009-05-01

Effects of 3 ionophores and 2 antibiotics on in vitro H(2)S production, IVDMD, total gas production, and VFA profile with or without added S were examined. In Exp. 1, ruminal fluid from 2 ruminally cannulated steers fed a steam-flaked corn-based diet (75% concentrate) without ionophore and antibiotics for 28 d before collection was used to inoculate in vitro cultures. Treatments were control (no ionophore or antibiotic), 3 ionophores (lasalocid sodium and monensin sodium at 5 mg/L or laidlomycin propionate at 1.65 mg/L), and 2 antibiotics (chlortetracycline hydrochloride at 5 mg/L and tylosin tartarate at 1.25 mg/L). Cultures also had 0 or 1.75 mg of S/L (from sodium sulfate). No S x ionophore-antibiotic treatment interactions were noted (P > 0.53) for IVDMD, total gas production, and H(2)S production. Hydrogen sulfide (mumol/g of fermentable DM) was increased (P production tended (P = 0.09) to be increased with additional S; however, IVDMD was not affected by added S (P = 0.90). Production of H(2)S was not affected by ionophores or antibiotics (P > 0.18). On average, IVDMD (P = 0.05) was greater for ionophores than for antibiotics, whereas total gas production was less for ionophores than for control (P antibiotics (P 0.20) in acetate, propionate, or acetate:propionate between ionophores and control (S x treatment interaction, P = 0.03). In Exp. 2, the effects of ionophore-antibiotic combinations with added S were examined using the same procedures as in Exp. 1. Treatments were control, monensin plus tylosin (MT), and lasalocid plus chlortetracycline (LCTC), with concentrations of the ionophores and antibiotics as in Exp. 1. No differences were observed among treatments for H(2)S production (P > 0.55). Treatments MT and LCTC tended (P = 0.06) to increase IVDMD and decreased (P = 0.02) gas production vs. control. Proportion of acetate (P = 0.01) and acetate:propionate (P antibiotics we evaluated did not affect production of H(2)S gas in an in vitro rumen culture

Longitudinal characterization of antimicrobial resistance genes in feces shed from cattle fed different subtherapeutic antibiotics

Directory of Open Access Journals (Sweden)

Read Ronald R

2011-01-01

Full Text Available Abstract Background Environmental transmission of antimicrobial-resistant bacteria and resistance gene determinants originating from livestock is affected by their persistence in agricultural-related matrices. This study investigated the effects of administering subtherapeutic concentrations of antimicrobials to beef cattle on the abundance and persistence of resistance genes within the microbial community of fecal deposits. Cattle (three pens per treatment, 10 steers per pen were administered chlortetracycline, chlortetracycline plus sulfamethazine, tylosin, or no antimicrobials (control. Model fecal deposits (n = 3 were prepared by mixing fresh feces from each pen into a single composite sample. Real-time PCR was used to measure concentrations of tet, sul and erm resistance genes in DNA extracted from composites over 175 days of environmental exposure in the field. The microbial communities were analyzed by quantification and denaturing gradient gel electrophoresis (DGGE of PCR-amplified 16S-rRNA. Results The concentrations of 16S-rRNA in feces were similar across treatments and increased by day 56, declining thereafter. DGGE profiles of 16S-rRNA differed amongst treatments and with time, illustrating temporal shifts in microbial communities. All measured resistance gene determinants were quantifiable in feces after 175 days. Antimicrobial treatment differentially affected the abundance of certain resistance genes but generally not their persistence. In the first 56 days, concentrations of tet(B, tet(C, sul1, sul2, erm(A tended to increase, and decline thereafter, whereas tet(M and tet(W gradually declined over 175 days. At day 7, the concentration of erm(X was greatest in feces from cattle fed tylosin, compared to all other treatments. Conclusion The abundance of genes coding for antimicrobial resistance in bovine feces can be affected by inclusion of antibiotics in the feed. Resistance genes can persist in feces from cattle beyond 175 days

Quality control of antibiotics before the implementation of an STD program in Northern Myanmar.

Science.gov (United States)

Prazuck, Thierry; Falconi, Isabelle; Morineau, Guy; Bricard-Pacaud, Véronique; Lecomte, Antoine; Ballereau, Francoise

2002-11-01

The ready availability of poor-quality drugs in developing countries leads to treatment failure and, consequently, excess mortality and morbidity. Moreover, the widespread availability of substandard drugs plays a key role in increasing the resistance to antimicrobial drugs.GOAL As a prerequisite to the establishment of a sexually transmitted disease (STD) control program, this study aimed to evaluate the quality of antibiotics recommended for treatment of STDs that were locally available in the capital of a province of Northern Myanmar. In addition to the hospital pharmacy, we selected at random 5 of the 41 drug sellers and 5 of the 40 general practitioners who sell antibiotics in the city of Myitkyina. Twenty-one marketing products corresponding to nine different antibiotics used for STD treatment were purchased (benzathine benzylpenicillin, benzylpenicillin, ceftriaxone, chlortetracycline, ciprofloxacin, clotrimazole, co-trimoxazole, doxycycline, and erythromycin). Drugs were sent to France, where they were analyzed according to the WHO guidelines. Drugs were considered to be standard if their dosage remained in the 10% range of the expected value. Among the 21 different specialty products, only three displayed the official "registered" label. Three drugs were expired and the expiration date was not available for six others. One product did not contain the active drug declared (chlortetracycline; Lombisin, Unicorn, China) and did not show any in vitro activity against bacteria. Seven of 21 products (33%) did not contain the stated dosage (1, more than stated dosage; 6, less than stated dosage). The highest deficit observed was 48% in two products (co-trimoxazole, Yong Fong, Myanmar; benzylpenicillin, China [city and manufacturer unknown]). The dosage was not available for five drugs. As a result, only 8 of 21 products (38%) did not contain the stated dosage of active drug. These findings suggest that public health policies based on national treatment guidelines

Chemiluminescence determination of tetracyclines using Fenton system in the presence europium(III) ions

Energy Technology Data Exchange (ETDEWEB)

Kaczmarek, Malgorzata [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland); Lis, Stefan [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland)

2009-04-20

A new simple chemiluminescent method for the determination of chlortetracycline (Chlor-TC), oxytetracycline (Oxy-TC) and doxycycline (Doxy-TC) is described. This method is based on the europium(III) emission as a result of the energy transfer process from the excited product of the tetracyclines oxidation to the uncomplexed Eu(III). Under the optimum conditions, calibration graphs were obtained for 4 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Chlor-TC; 2 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Oxy-TC and 1 x 10{sup -7} to 3 x 10{sup -5} mol L{sup -1} of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

76 FR 49649 - Oral Dosage Form New Animal Drugs; Change of Sponsor; Chlortetracycline; Sulfamethazine

Science.gov (United States)

2011-08-11

... of Pfizer, Inc., to Boehringer Ingelheim Vetmedica, Inc. DATES: This rule is effective August 11...-018, 055-039, 065-071, and 065-440) to Boehringer Ingelheim Vetmedica, Inc., 2621 North Belt Highway...

Hierarchical La{sub 0.7}Ce{sub 0.3}FeO{sub 3}/halloysite nanocomposite for photocatalytic degradation of antibiotics

Energy Technology Data Exchange (ETDEWEB)

Li, Xiazhang; Yao, Chao [Changzhou University, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou (China); Chinese Academy of Science, R and D Center of Xuyi Attapulgite Applied Technology, Xuyi (China); Zhu, Wei; Yan, Xiangyu [Changzhou University, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou (China); Lu, Xiaowang [Chinese Academy of Science, R and D Center of Xuyi Attapulgite Applied Technology, Xuyi (China); Ni, Chaoying [University of Delaware, Center for Advanced Microscopy and Microanalysis, Newark, DE (United States)

2016-08-15

The hierarchical La{sub 0.7}Ce{sub 0.3}FeO{sub 3}/halloysite nanotubes (HNTs) composites have been successfully prepared via sol-gel method. XRD and TEM characterizations indicated that the sheet-like La{sub 0.7}Ce{sub 0.3}FeO{sub 3} coupled with the co-precipitated CeO{sub 2} were evenly deposited onto the surface of halloysite. The photocatalytic degradation of chlortetracycline under visible light irradiation using La{sub 0.7}Ce{sub 0.3}FeO{sub 3}/HNTs as catalyst was evaluated by high-performance liquid chromatography, which exhibited remarkable photocatalytic activity with the removal rate up to 99 % in 90 min, due to the formation of ''solid solution/co-precipitation'' heterostructure as well as the excellent adsorptive capability of halloysite for antibiotics. (orig.)

Ultrasensitive chemiluminescence of tetracyclines in the presence of MCLA

Energy Technology Data Exchange (ETDEWEB)

Zeng, Wangsheng; Zhu, Chenyao [School of Public Health, Nanchang University, Nanchang 330006 (China); Liu, Hongcheng [Institute of Quality Standard and Testing Technology, Yunnan Academy of Agriculture Science, 650223 Kunming (China); Liu, Jing; Cai, Hongping [School of Public Health, Nanchang University, Nanchang 330006 (China); Cheng, Xianglei, E-mail: chengxlsd@163.com [School of Public Health, Nanchang University, Nanchang 330006 (China); Wei, Lijun, E-mail: weilj7681@163.com [School of Public Health, Nanchang University, Nanchang 330006 (China)

2017-06-15

In this article, five tetracyclines (TCs) showed ultrasensitive chemiluminescence (CL) based on the novel CL system of methoxylated Cypridina luciferin analogues (MCLA) and Ce(IV). It was found that the CL intensity of MCLA-Ce(IV) system was enhanced 30 times by adding 10 pmol chlortetracycline. Mechanisms of MCLA-Ce(IV)-TCs were investigated by CL spectra, radical scavengers and UV spectra. The results indicated that singlet oxygen, resulting from the reaction between Ce(IV) and TCs, was involved in the enhancement of CL phenomenon. This CL system coupling with flow injection analysis was developed for the determination of five common TCs. Linear ranged from 100 fmol to 20 pmol (r>0.999) with limit of detection of 20 to 50 fmol (S/N=3). The sensitivity of the present method is comparable to that of UPLC-MS/MS detection for TCs.

Occurrence and transformation of veterinary antibiotics and antibiotic resistance genes in dairy manure treated by advanced anaerobic digestion and conventional treatment methods.

Science.gov (United States)

Wallace, Joshua S; Garner, Emily; Pruden, Amy; Aga, Diana S

2018-05-01

Manure treatment technologies are rapidly developing to minimize eutrophication of surrounding environments and potentially decrease the introduction of antibiotics and antibiotic resistant genes (ARGs) into the environment. While laboratory and pilot-scale manure treatment systems boast promising results, antibiotic and ARG removals in full-scale systems receiving continuous manure input have not been evaluated. The effect of treatment on ARGs is similarly lacking. This study examines the occurrence and transformation of sulfonamides, tetracyclines, tetracycline degradation products, and related ARGs throughout a full-scale advanced anaerobic digester (AAD) receiving continuous manure and antibiotic input. Manure samples were collected throughout the AAD system to evaluate baseline antibiotic and ARG input (raw manure), the effect of hygenization (post-pasteurized manure) and anaerobic digestion (post-digestion manure) on antibiotic and ARG levels. Antibiotics were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the ARGs tet(O), tet(W), sul1 and sul2 were analyzed by quantitative polymerase chain reaction (Q-PCR). Significant reductions in the concentrations of chlortetracycline, oxytetracycline, tetracycline and their degradation products were observed in manure liquids following treatment (p < 0.001), concomitant to significant increases in manure solids (p < 0.001). These results suggest sorption is the major removal route for tetracyclines during AAD. Significant decreases in the epimer-to-total residue ratios for chlortetracycline and tetracycline in manure solids further indicate degradation is desorption-limited. Moreover, sul1 and sul2 copies decreased significantly (p < 0.001) following AAD in the absence of sulfonamide antibiotics, while tetracyclines-resistant genes remained unchanged. A cross-sectional study of dairy farms utilizing natural aeration and liquid-solid separation treatments was additionally performed

Efficacy of salicylic acid in the treatment of digital dermatitis in dairy cattle

DEFF Research Database (Denmark)

Schultz, N.; Capion, N.

2013-01-01

Digital dermatitis (DD) is one of the most important causes of lameness in dairy cattle worldwide. The objective of this study was to evaluate the efficacy of salicylic acid in the treatment of the disease. A total of 201 DD lesions from 173 cows from four commercial dairy herds were evaluated...... at day 0 during routine hoof trimming and were allocated into two groups, namely, a control group given chlortetracycline spray, and a treatment group given 10 g of salicylic acid powder applied topically within a bandage. Pain, lesion size and clinical appearance (scored MO to M4) were evaluated on days...... the control group were 2.2 times more likely (P = 0.09) to have a pain score equal to 2 by day 14. The proportion of lesions getting smaller by days 14 and 34 was 2.5 times higher (P salicylic acid should be considered as an alternative...

Mass flows and removal of antibiotics in two municipal wastewater treatment plants.

Science.gov (United States)

Li, Bing; Zhang, Tong

2011-05-01

The mass flows and removal of 20 antibiotics of seven classes in two wastewater treatment plants (WWTPs) of Hong Kong were investigated in different seasons of a whole year, using bihourly 24h flow proportional composite samples. Antibiotics were detected at concentrations of 3.2-1718, 1.3-1176 and 1.1-233ngL(-1) in influents, secondary and disinfection effluents. Total daily discharges of all the detected antibiotics from effluents of Shatin and Stanley WWTPs were 470-710 and 3.0-5.2gd(-1), respectively. Ampicillin, cefalexin, sulfamethoxazole, sulfadiazine, sulfamethazine, chlortetracycline and vancomycin were effectively (52-100%) eliminated by activated sludge process while ampicillin and cefalexin were effectively (91-99%) eliminated by disinfection. Bihourly variation analysis showed that concentrations of the major antibiotics in influents varied more significantly in Stanley WWTP which served small communities. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of in-feed Chlortetracycline prophylaxis in beef cattle on levels of 10 antimicrobial resistance genes

Science.gov (United States)

Background: The majority of antimicrobial products used in food-animal production are administered in-feed to control or prevent disease. These uses are controversial since it has been argued that they have contributed to increased occurrence of antimicrobial resistance (AMR). Beef cattle are suscep...

Graphene quantum dots /LaCoO3/attapulgite heterojunction photocatalysts with improved photocatalytic activity

International Nuclear Information System (INIS)

Zhu, Wei; Li, Xiazhang

2017-01-01

A new nanocomposite of graphene quantum dots/LaCoO 3 /attapulgite (GQDs/LaCoO 3 /ATP) was prepared by a facile impregnation method and was applied to degradation of the organic pollutants as photocatalyst under visible light irradiation. Multiple techniques were used to characterize the structures, morphologies and photocatalytic activities of samples. The photocatalytic activity of the GQDs/LaCoO 3 /ATP nanocomposites was effectively evaluated using Methylene blue (MB), antibiotic agent chlortetracycline (CHL) and tetracycline hydrochloride (TC). The as-synthesized GQDs/LaCoO 3 /ATP nanocomposites exhibited higher photocatalytic activities than LaCoO 3 /ATP, which showed a broad spectrum of photocatalytic degradation activity. The results of ESR and free radicals trapping experiments indicated that circle OH and h + were the main species for the photocatalytic degradation. GQDs played a significant role in the photocatalytic activity improvement of LaCoO 3 /ATP, increasing the visible light absorption, slowing the recombination and improving the charge transfer. (orig.)

Graphene quantum dots /LaCoO3/attapulgite heterojunction photocatalysts with improved photocatalytic activity

Science.gov (United States)

Zhu, Wei; Li, Xiazhang

2017-04-01

A new nanocomposite of graphene quantum dots/LaCoO3/attapulgite (GQDs/LaCoO3/ATP) was prepared by a facile impregnation method and was applied to degradation of the organic pollutants as photocatalyst under visible light irradiation. Multiple techniques were used to characterize the structures, morphologies and photocatalytic activities of samples. The photocatalytic activity of the GQDs/LaCoO3/ATP nanocomposites was effectively evaluated using Methylene blue (MB), antibiotic agent chlortetracycline (CHL) and tetracycline hydrochloride (TC). The as-synthesized GQDs/LaCoO3/ATP nanocomposites exhibited higher photocatalytic activities than LaCoO3/ATP, which showed a broad spectrum of photocatalytic degradation activity. The results of ESR and free radicals trapping experiments indicated that • OH and h+ were the main species for the photocatalytic degradation. GQDs played a significant role in the photocatalytic activity improvement of LaCoO3/ATP, increasing the visible light absorption, slowing the recombination and improving the charge transfer.

Occurrence of antibiotics in soils and manures from greenhouse vegetable production bases of Beijing, China and an associated risk assessment.

Science.gov (United States)

Li, Cheng; Chen, Jiayi; Wang, Jihua; Ma, Zhihong; Han, Ping; Luan, Yunxia; Lu, Anxiang

2015-07-15

The occurrence of 15 antibiotics in soil and manure samples from 11 large-scale greenhouse vegetable production (GVP) bases in Beijing, China was investigated. Results showed that the greenhouse soils were ubiquitously contaminated with antibiotics, and that antibiotic concentrations were significantly higher in greenhouses than in open field soils. The mean concentrations of four antibiotic classes decreased in the following order: tetracyclines (102μg/kg)>quinolones (86μg/kg)>sulfonamides (1.1μg/kg)>macrolides (0.62μg/kg). This investigation also indicated that fertilization with manure and especially animal feces might be the primary source of antibiotics. A risk assessment based on the calculated risk quotients (RQs) demonstrated that oxytetracycline, chlortetracycline, norfloxacin, ciprofloxacin and enrofloxacin could pose a high risk to soil organisms. These results suggested that the ecological effects of antibiotic contamination in GVP bases and their potential adverse risks on human health need to be given special attention. Copyright © 2015 Elsevier B.V. All rights reserved.

Molecular typing and antimicrobial susceptibility of Clostridium perfringens from broiler chickens.

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Gharaibeh, Saad; Al Rifai, Rami; Al-Majali, Ahmad

2010-12-01

Clostridium perfringens (Cp) causes necrotic enteritis disease in commercial poultry. Antimicrobials are used to control and treat this disease and sometimes clinical outbreaks do not respond well to certain treatments. This study was designed to isolate Cp from clinical cases, type these isolates by multiplex PCR, and determine their antimicrobial susceptibility by micro-dilution method. A total of 67 Cp isolates were obtained from 155 broiler chicken flocks. All isolates were classified as type A and non-enterotoxin producers. Lincomycin, erythromycins, and tilmicosin showed very high minimal inhibitory concentration (MIC) 50 of ≥256 μg/ml. However, tylosin, amoxicillin, ampicillin, penicillin, florfenicol, danofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline had variable MIC₅₀ of 64, 0.5, 1, 1, 8, 4, 8, 4, 8, 0.5 μg/ml, respectively. It is recommended that Cp infections in Jordan be treated with either penicillins or tetracyclines especially amoxicillin and oxytetracycline. Copyright © 2010 Elsevier Ltd. All rights reserved.

Boar sperm storage capacity of BTS and Androhep Plus: viability, motility, capacitation, and tyrosine phosphorylation.

Science.gov (United States)

Dubé, Charlotte; Beaulieu, Martin; Reyes-Moreno, Carlos; Guillemette, Christine; Bailey, Janice L

2004-09-01

Androhep Plus, a long-term extender (up to 7 days) and Beltsville Thawing Solution (BTS), a short-term extender (up to 3 days), are commonly used for liquid storage of porcine semen. To test the hypothesis that modifications in sperm viability, motility, chlortetracycline (CTC) fluorescence patterns, and protein tyrosine phosphorylation occur during semen storage in extenders, we compared these end points at different periods of storage in either Androhep Plus or BTS. Sperm from five boars were assessed daily over 12 days of storage (n = 5 ejaculates from different boars). Viability was not different (P extenders, except on Day 2, when Androhep Plus maintained better viability. Differences in the percentage of motile (total) sperm due to extender were evident on Days 2, 4, 5, and 6, when Androhep Plus was superior to BTS (P extender as early as Day 2; storage in Androhep Plus induced higher levels of pattern B sperm (P extenders; these may affect the fertilizing capacity of the semen.

Long-Term Exposure of Agricultural Soil to Veterinary Antibiotics Changes the Population Structure of Symbiotic Nitrogen-Fixing Rhizobacteria Occupying Nodules of Soybeans (Glycine max).

Science.gov (United States)

Revellin, Cécile; Hartmann, Alain; Solanas, Sébastien; Topp, Edward

2018-05-01

Antibiotics are entrained in agricultural soil through the application of manures from medicated animals. In the present study, a series of small field plots was established in 1999 that receive annual spring applications of a mixture of tylosin, sulfamethazine, and chlortetracycline at concentrations ranging from 0.1 to 10 mg · kg -1 soil. These antibiotics are commonly used in commercial swine production. The field plots were cropped continuously for soybeans, and in 2012, after 14 annual antibiotic applications, the nodules from soybean roots were sampled and the occupying bradyrhizobia were characterized. Nodules and isolates were serotyped, and isolates were distinguished using 16S rRNA gene and 16S to 23S rRNA gene intergenic spacer region sequencing, multilocus sequence typing, and RSα fingerprinting. Treatment with the antibiotic mixture skewed the population of bradyrhizobia dominating the nodule occupancy, with a significantly larger proportion of Bradyrhizobium liaoningense organisms even at the lowest dose of 0.1 mg · kg -1 soil. Likewise, all doses of antibiotics altered the distribution of RSα fingerprint types. Bradyrhizobia were phenotypically evaluated for their sensitivity to the antibiotics, and there was no association between in situ treatment and a decreased sensitivity to the drugs. Overall, long-term exposure to the antibiotic mixture altered the composition of bradyrhizobial populations occupying nitrogen-fixing nodules, apparently through an indirect effect not associated with the sensitivity to the drugs. Further work evaluating agronomic impacts is warranted. IMPORTANCE Antibiotics are entrained in agricultural soil through the application of animal or human waste or by irrigation with reused wastewater. Soybeans obtain nitrogen through symbiotic nitrogen fixation. Here, we evaluated the impact of 14 annual exposures to antibiotics commonly used in swine production on the distribution of bradyrhizobia occupying nitrogen

Effects of in-feed Chlortetracycline Prophylaxis of beef cattle on animal health and antimicrobial-resistant Escherichia coli

Science.gov (United States)

Objective: The objective of this study was to evaluate the effect of a one-time, five-day in-feed CTC prophylaxis on animal health (morbidity and body weight gain), occurrence of TETr E. coli, and occurrence of 3GCr E. coli over a four-month follow-up period. Experimental Design & Analysis: We eval...

Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities

International Nuclear Information System (INIS)

Liu Feng; Ying Guangguo; Tao Ran; Zhao Jianliang; Yang Jifeng; Zhao Lanfeng

2009-01-01

The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was most sensitive to sulfamethoxazole with the EC10 value of 0.1 mg/L. The antibiotics tested inhibited soil phosphatase activity during the 22 days' incubation. Significant effects on soil respiration were found for the two sulfonamides (sulfamethoxazole and sulfamethazine) and trimethoprim, whereas little effects were observed for the two tetracyclines and tylosin. The effective concentrations (EC10 values) for soil respiration in the first 2 days were 7 mg/kg for sulfamethoxazole, 13 mg/kg for sulfamethazine and 20 mg/kg for trimethoprim. Antibiotic residues in manure and soils may affect soil microbial and enzyme activities. - Terrestrial ecotoxicological effects of antibiotics are related to their sorption and degradation behavior in soil.

Impact of medicated feed along with clay mineral supplementation on Escherichia coli resistance to antimicrobial agents in pigs after weaning in field conditions.

Science.gov (United States)

Jahanbakhsh, Seyedehameneh; Kabore, Kiswendsida Paul; Fravalo, Philippe; Letellier, Ann; Fairbrother, John Morris

2015-10-01

The aim of this study was to examine changes in antimicrobial resistance (AMR) phenotype and virulence and AMR gene profiles in Escherichia coli from pigs receiving in-feed antimicrobial medication following weaning and the effect of feed supplementation with a clay mineral, clinoptilolite, on this dynamic. Eighty E. coli strains isolated from fecal samples of pigs receiving a diet containing chlortetracycline and penicillin, with or without 2% clinoptilolite, were examined for antimicrobial resistance to 15 antimicrobial agents. Overall, an increased resistance to 10 antimicrobials was observed with time. Supplementation with clinoptilolite was associated with an early increase but later decrease in blaCMY-2, in isolates, as shown by DNA probe. Concurrently, a later increase in the frequency of blaCMY-2 and the virulence genes iucD and tsh was observed in the control pig isolates, being significantly greater than in the supplemented pigs at day 28. Our results suggest that, in the long term, supplementation with clinoptilolite could decrease the prevalence of E. coli carrying certain antimicrobial resistance and virulence genes. Copyright © 2015 Elsevier Ltd. All rights reserved.

A novel green chemistry method for nonaqueous extraction and high-performance liquid chromatography detection of first-, second-, and third-generation tetracyclines, 4-epitetracycline, and tylosin in animal feeds.

Science.gov (United States)

Granados-Chinchilla, Fabio; Sánchez, Jorge; García, Fernando; Rodríguez, César

2012-07-25

Although tetracyclines and macrolides are common additives for animal nutrition, methods for their simultaneous determination in animal feeds are nonexistent. By coupling an organic extraction and solid-phase extraction cleanup to a high-performance liquid chromatography separation and a nonaqueous postcolumn derivatization, we succeeded in detecting from 0.2 to 24.0 μg kg(-1) of tetracycline, oxytetracycline, chlortetracycline, doxycycline, tigecycline, and 4-epitetracycline in this complex and heterogeneous matrix. Minocycline and tylosin could also be detected with our procedure, but using UV spectrophotometry (1.5 ≤ LOD ≤ 1.9 mg kg(-1)). Linear responses with correlation coefficients between 0.996 and 0.999 were obtained for all analytes in the 0.5-10 mg kg(-1) concentration range. Average recoveries between 59 and 97% and between 98 and 102% were obtained for the tetracyclines and tylosin, respectively. Replicate standard deviations were typically below 5%. When this method was applied to 20 feeds marketed in Costa Rica, we detected labeling inconsistencies, banned mixtures of tetracyclines, and tetracycline concentrations that contravene international regulation.

The detection limits of antimicrobial agents in cow's milk by a simple Yoghurt Culture Test.

Science.gov (United States)

Mohsenzadeh, M; Bahrainipour, A

2008-09-15

The aim of this study was to study performance of Yoghurt Culture Test (YCT) in the detection of antimicrobial residues in milk. For this purpose, the sensitivity of YCT for 15 antibiotics were determined. For each drug, 8 concentrations were tested. The detection limits of YCT at 2.5 h and 4 h incubation were determined (microg kg(-1)): 15 and 37.5, penicillin G; 4 and 5, ampicillin; 5 and 7.5, amoxycillin; 100 and 200, cephalexin; 80 and 100, cefazoline; 100 and 200, oxytetracycline; 500 and 100, chlortetracycline; 100 and 200, tetracycline; 150 and 200, doxycycline; 200 and 400, sulphadimidine; 500 and 1000, gentamycin; 1000 and 1500, spectinomycin; 400 and 500, erythromycin; 50 and 100, tylosin; 5000 and 10000, chloramphenicol. The YCT detection limits at 2.5 h incubation for ampicillin, cephalexin, tetracycline, oxytetracycline and tylosin are similar to those obtained as Maximum Residue Limit (MRL) according to Regulation 2377/90 EEC as set out by the European Union. In addition the detection limits of YCT for some antibiotics were lower than some of microbial inhibitor test.

Comparison of methods for in vitro testing of susceptibility of porcine Mycoplasma species to antimicrobial agents.

Science.gov (United States)

Ter Laak, E A; Pijpers, A; Noordergraaf, J H; Schoevers, E C; Verheijden, J H

1991-02-01

The MICs of 18 antimicrobial agents used against strains of three porcine Mycoplasma species were determined by a serial broth dilution method. Twenty field strains of M. hyorhinis, ten field strains of M. hyopneumoniae, six field strains of M. flocculare, and the type strains of these species were tested. Twelve field strains and the type strain of M. hyorhinis were also tested by an agar dilution method. Tests were read at various time points. When the broth dilution method was used, the final MIC had to be read 2 days after color changes had stopped. MICs of tetracycline, oxytetracycline, doxycycline, and minocycline were low for the three Mycoplasma species tested. MICs of chlortetracycline were 8 to 16 times higher than MICs of the other tetracyclines. Spiramycin, tylosin, kitasamycin, spectinomycin, tiamulin, lincomycin, and clindamycin were effective against all strains of M. hyorhinis and M. hyopneumoniae. The quinolones were highly effective against M. hyopneumoniae but less effective against M. hyorhinis. The susceptibility patterns for M. hyopneumoniae and M. flocculare were similar.

Multiclass determination and confirmation of antibiotic residues in honey using LC-MS/MS.

Science.gov (United States)

Lopez, Mayda I; Pettis, Jeffery S; Smith, I Barton; Chu, Pak-Sin

2008-03-12

A multiclass method has been developed for the determination and confirmation in honey of tetracyclines (chlortetracycline, doxycycline, oxytetracycline, and tetracycline), fluoroquinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, and sarafloxacin), macrolides (tylosin), lincosamides (lincomycin), aminoglycosides (streptomycin), sulfonamides (sulfathiazole), phenicols (chloramphenicol), and fumagillin residues using liquid chromatography tandem mass spectrometry (LC-MS/MS). Erythromycin (a macrolide) and monensin (an ionophore) can be detected and confirmed but not quantitated. Honey samples (approximately 2 g) are dissolved in 10 mL of water and centrifuged. An aliquot of the supernatant is used to determine streptomycin. The remaining supernatant is filtered through a fine-mesh nylon fabric and cleaned up by solid phase extraction. After solvent evaporation and sample reconstitution, 15 antibiotics are assayed by LC-MS/MS using electrospray ionization (ESI) in positive ion mode. Afterward, chloramphenicol is assayed using ESI in negative ion mode. The method has been validated at the low part per billion levels for most of the drugs with accuracies between 65 and 104% and coefficients of variation less than 17%. The evaluation of matrix effects caused by honey of different floral origin is presented.

Antibiotic susceptibility of Brachyspira hyodysenteriae isolates from Czech swine farms: a 10-year follow-up study

Directory of Open Access Journals (Sweden)

Josef Prášek

2014-01-01

Full Text Available Brachyspira hyodysenteriae is the causative agent of swine dysentery. Loss of clinical efficacy of some antimicrobial agents authorized for treating swine dysentery was observed on certain Czech pig farms. The aim of the present study was to evaluate the antimicrobial sensitivity of six antibiotics using a set of 202 randomly selected B. hyodysenteriae isolates obtained from farms in the Czech Republic between years 1997 and 2006. Minimum inhibitory concentration of antibiotics tylosin, lincomycin, tylvalosin, chlortetracyclin, tiamulin and valnemulin were tested, using an agar dilution method. All antibiotics tested showed an increase in minimal inhibitory concentrations. Continual decrease in susceptibility of B. hyodysenteriae isolates to tiamulin and valnemulin was observed. Multiresistant B. hyodysenteriae were isolated more frequently in the past years. Only a careful use of antibiotics can ensure their efficacy, especially in case of pleuromutilins, in the strategic therapy of swine dysentery. This rare study demonstrates the minimal inhibitory concentration changes of selected antidysenterics among Czech isolates of Brachyspira hyodysenteriae during a ten-year period.

The use of dissolvable layered double hydroxide components in an in situ solid-phase extraction for chromatographic determination of tetracyclines in water and milk samples.

Science.gov (United States)

Phiroonsoontorn, Nattaphorn; Sansuk, Sira; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

2017-10-13

This research presents a simple and green in situ solid phase extraction (is-SPE) combined with high-performance liquid chromatography (HPLC) for the simultaneous analysis of tetracyclines (TCs) including tetracycline, oxytetracycline, and chlortetracycline. In is-SPE, TCs were efficiently extracted through the precipitation formation of dissolvable layered double hydroxides (LDHs) by mixing the LDH components such as magnesium and aluminum ions (both in metal chloride salts) thoroughly in an alkaline sample solution. After the centrifugation, the precipitate was completely dissolved with trifluoroacetic acid to release the enriched TCs, and then analyzed by HPLC. Under optimized conditions, this method gave good enrichment factors (EFs) of 41-93 with low limits of detection (LODs) of 0.7-6μg/L and limits of quantitation (LOQs) of 3-15μg/L. Also, the proposed method was successfully applied for the determination of TCs in water and milk samples with the recoveries ranging from 81.7-108.1% for water and 55.7-88.7% for milk. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultimate methane yield from beef cattle manure: effect of temperature, ration constituents, antibiotics and manure age

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, A G; Varel, V H; Chen, Y R

1981-10-01

The effects of temperature, ration constituents, antibiotics and manure age on the ultimate methane yield (Bo, litre CH4/g volatile solids fed (VSf)) were investigated using 4-litre batch fermenters. The average Bo for fermenters maintained at 30-60 degrees Celcius (at 5 degrees Celcius intervals) was 0.328 litre CH4/g VSf. The Bo at 65 degrees Celcius averaged 0.118 litre CH4g VSf, but this low yield was attributed to unstable fermentation rather than decreased substrate availability at that temperature. These results agreed well with Bo values estimated from daily-fed fermenters. Chlortetracycline and monensin did not affect Bo; however, monensin did delay the start of active fermentation in batch fermenters. The average Bo of manure from cattle fed 91.5, 40 and 7% corn silage were 0.173, 0.232 and 0.290 litre CH4/g VSf, respectively. The average Bo for 6-8 week old manure from a dirt feedlot was 0.210 litre CH4/g VSf. (Refs. 14).

Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities

Energy Technology Data Exchange (ETDEWEB)

Liu Feng [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Ying Guangguo, E-mail: guangguo.ying@gmail.co [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Tao Ran; Zhao Jianliang; Yang Jifeng [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Zhao Lanfeng [College of Resource and Environmental Science, South China Agricultural University, Guangzhou 510642 (China)

2009-05-15

The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was most sensitive to sulfamethoxazole with the EC10 value of 0.1 mg/L. The antibiotics tested inhibited soil phosphatase activity during the 22 days' incubation. Significant effects on soil respiration were found for the two sulfonamides (sulfamethoxazole and sulfamethazine) and trimethoprim, whereas little effects were observed for the two tetracyclines and tylosin. The effective concentrations (EC10 values) for soil respiration in the first 2 days were 7 mg/kg for sulfamethoxazole, 13 mg/kg for sulfamethazine and 20 mg/kg for trimethoprim. Antibiotic residues in manure and soils may affect soil microbial and enzyme activities. - Terrestrial ecotoxicological effects of antibiotics are related to their sorption and degradation behavior in soil.

Solid-Phase Extraction and Large-Volume Sample Stacking-Capillary Electrophoresis for Determination of Tetracycline Residues in Milk

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Gabriela Islas

2018-01-01

Full Text Available Solid-phase extraction in combination with large-volume sample stacking-capillary electrophoresis (SPE-LVSS-CE was applied to measure chlortetracycline, doxycycline, oxytetracycline, and tetracycline in milk samples. Under optimal conditions, the proposed method had a linear range of 29 to 200 µg·L−1, with limits of detection ranging from 18.6 to 23.8 µg·L−1 with inter- and intraday repeatabilities < 10% (as a relative standard deviation in all cases. The enrichment factors obtained were from 50.33 to 70.85 for all the TCs compared with a conventional capillary zone electrophoresis (CZE. This method is adequate to analyze tetracyclines below the most restrictive established maximum residue limits. The proposed method was employed in the analysis of 15 milk samples from different brands. Two of the tested samples were positive for the presence of oxytetracycline with concentrations of 95 and 126 µg·L−1. SPE-LVSS-CE is a robust, easy, and efficient strategy for online preconcentration of tetracycline residues in complex matrices.

Hormetic effect(s) of tetracyclines as environmental contaminant on Zea mays

International Nuclear Information System (INIS)

Migliore, Luciana; Godeas, Feliciana; De Filippis, Stefania Paola; Mantovi, Paolo; Barchi, Davide; Testa, Cecilia; Rubattu, Nicolino; Brambilla, Gianfranco

2010-01-01

Animal wastes from intensive pig farming as fertilizers may expose crops to antimicrobials. Zea mays cultivations were carried out on a virgin field, subjected to dressing with pig slurries contaminated at 15 mg L -1 of Oxy- and 5 mg L -1 of Chlor-tetracycline, and at 8 mg L -1 of Oxy and 3 mg L -1 of Chlor, respectively. Pot cultivation was performed outdoor (Oxy in the range 62.5-1000 ng g -1 dry soil) and plants harvested after 45 days. Tetracyclines analyses on soils and on field plants (roots, stalks, and leaves) did not determine the appreciable presence of tetracyclines. Residues were found in the 45-day pot corn only, in the range of 1-50 ng g -1 for Oxy in roots, accounting for a 5% carry-over rate, on average. Although no detectable residues in plants from on land cultivations, both experimental batches showed the same biphasic growth form corresponding to a dose/response hormetic curve. - Oxytetracycline in soils elicits a hormetic response in Zea mays plants.

Hormetic effect(s) of tetracyclines as environmental contaminant on Zea mays

Energy Technology Data Exchange (ETDEWEB)

Migliore, Luciana; Godeas, Feliciana [Dipartimento di Biologia, Universita Tor Vergata, Rome (Italy); De Filippis, Stefania Paola [Istituto Superiore di Sanita, Toxicological Chemistry Unit, Rome (Italy); Mantovi, Paolo [Centro Ricerche Produzioni Animali, Reggio Emilia (Italy); Barchi, Davide [Assessorato all' Agricoltura, Regione Emilia-Romagna, Bologna (Italy); Testa, Cecilia; Rubattu, Nicolino [Istituto Zooprofilattico Sperimentale della Sardegna, Sassari (Italy); Brambilla, Gianfranco [Istituto Superiore di Sanita, Toxicological Chemistry Unit, Rome (Italy)

2010-01-15

Animal wastes from intensive pig farming as fertilizers may expose crops to antimicrobials. Zea mays cultivations were carried out on a virgin field, subjected to dressing with pig slurries contaminated at 15 mg L{sup -1} of Oxy- and 5 mg L{sup -1} of Chlor-tetracycline, and at 8 mg L{sup -1} of Oxy and 3 mg L{sup -1} of Chlor, respectively. Pot cultivation was performed outdoor (Oxy in the range 62.5-1000 ng g{sup -1} dry soil) and plants harvested after 45 days. Tetracyclines analyses on soils and on field plants (roots, stalks, and leaves) did not determine the appreciable presence of tetracyclines. Residues were found in the 45-day pot corn only, in the range of 1-50 ng g{sup -1} for Oxy in roots, accounting for a 5% carry-over rate, on average. Although no detectable residues in plants from on land cultivations, both experimental batches showed the same biphasic growth form corresponding to a dose/response hormetic curve. - Oxytetracycline in soils elicits a hormetic response in Zea mays plants.

One-Step Preparation of Graphene Oxide/Cellulose Nanofibril Hybrid Aerogel for Adsorptive Removal of Four Kinds of Antibiotics

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Jin Wang

2017-01-01

Full Text Available Via a one-step ultrasonication method, cellulose nanofibril/graphene oxide hybrid (GO-CNF aerogel was successfully prepared. The as-prepared GO-CNF possessed interconnected 3D network microstructure based on GO nanosheets grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward four kinds of antibiotics. The removal percentages (R% of these antibiotics were 81.5%, 79.5%, 79.1%, and 73.9% for Doxycycline (DXC, Chlortetracycline (CTC, Oxytetracycline (OTC, and tetracycline (TC, respectively. Simultaneously, the adsorption isotherms were well fitted to Langmuir model and kinetics study implied that the adsorption process was attributed to pseudo-second-order model. The maximum theoretical adsorption capacities of GO-CNF were 469.7, 396.5, 386.5, and 343.8 mg·g−1 for DXC, CTC, OTC, and TC, respectively, calculated by the Langmuir isotherm models. After five cycles, importantly, the regenerated aerogels still could be used with little degradation of adsorption property. Consequently, the as-synthesized GO-CNF was a successful application of effective removal of antibiotics.

Effects of a mixture of tetracyclines to Lemna gibba and Myriophyllum sibiricum evaluated in aquatic microcosms

Energy Technology Data Exchange (ETDEWEB)

Brain, Richard A [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Wilson, Christian J [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Johnson, David J [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Sanderson, Hans [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Bestari, Ketut [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Hanson, Mark L [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Sibley, Paul K [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Solomon, Keith R [Centre for Toxicology, Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada)

2005-12-15

The impact of a mixture of oxytetracycline, chlortetracycline, tetracycline and doxycycline on Myriophyllum sibiricum and Lemna gibba was investigated using fifteen 12,000-L microcosms (k = 5, n = 3). Significant concentration-response relationships were only found for M. sibiricum, where dry mass was 69, 47, 30, and 7% of controls at respective treatment concentrations of 0.080, 0.218, 0.668, and 2.289 {mu}mol/L. Somatic endpoints were strongly and negatively correlated with percent light transmission, except plant length, which was positively correlated. Treated microcosms experienced a reduction in the percent of surface irradiance penetrating the water column as high as 99.8% at a depth of 70 cm, relative to controls. Position relative to the water column was likely responsible for the differential effects observed between floating (L. gibba) and submerged (M. sibiricum) species of macrophytes. A hazard quotient assessment of the lowest EC{sub 10} value indicated significant risk, exceeding the critical HQ value, but not the lowest EC{sub 25} value. - Mixtures of tetracycline antibiotics pose a risk to submerged but not floating aquatic plants.

Susceptibility of Clostridium perfringens strains from broiler chickens to antibiotics and anticoccidials.

Science.gov (United States)

Martel, A; Devriese, L A; Cauwerts, K; De Gussem, K; Decostere, A; Haesebrouck, F

2004-02-01

Clostridium perfringens strains isolated in 2002 from the intestines of broiler chickens from 31 different farms located in Belgium were tested for susceptibility to 12 antibiotics used for therapy, growth promotion or prevention of coccidiosis. All strains were uniformly sensitive to the ionophore antibiotics monensin, lasalocid, salinomycin, maduramycin and narasin. All were sensitive to avilamycin, tylosin and amoxicillin, while flavomycin (bambermycin) showed low or no activity. Chlortetracycline and oxytetracycline were active at very low concentrations, but low-level acquired resistance was detected in 66% of the strains investigated. Fifty percent of these strains carried the tetP(B) resistance gene, while the tet(Q) gene was detected in only one strain. One strain with high-level resistance against tetracyclines carried the tet(M) gene. Sixty-three percent of the strains showed low-level resistance to lincomycin. The lnu(A) and lnu(B) genes were each only found in one strain. Compared with a similar investigation carried out in 1980, an increase was seen in resistance percentages with lincomycin (63% against 49%) and a slight decrease with tetracycline (66% against 74%).

Biochemical effects of veterinary antibiotics on proliferation and cell cycle arrest of human HEK293 cells.

Science.gov (United States)

Kim, Hyeon Young; Kim, Ki-Tae; Kim, Sang Don

2012-08-01

The purpose of this study was to examine the effects of veterinary antibiotics, including amoxicillin (AMX), chlortetracycline (CTC) and tylosin (TYL), on the biochemical mechanism of human embryonic kidney cells (HEK293). CTC and TYL inhibited HEK293 cell proliferation, in both time- and dose-dependent manners, and changed the cell morphology; whereas, AMX showed no cytotoxic effects. The cell cycle analysis of CTC and TYL revealed G1-arrest in HEK293 cells. Western blot analysis also showed that CTC and TYL affected the activation of DNA damage responsive proteins, as well as cell cycle regulatory proteins, such as p53, p21(Waf1/Cip1) and Rb protein, which are crucial in the G1-S transition. The activation of p21(Waf1/Cip1) was significantly up-regulated over time, but there was no change in the level of CDK2 expression. The results of this study suggest that veterinary antibiotics, even at low level concentrations on continuous exposure, can potentially risk the development of human cells.

Effects of a mixture of tetracyclines to Lemna gibba and Myriophyllum sibiricum evaluated in aquatic microcosms

International Nuclear Information System (INIS)

Brain, Richard A.; Wilson, Christian J.; Johnson, David J.; Sanderson, Hans; Bestari, Ketut; Hanson, Mark L.; Sibley, Paul K.; Solomon, Keith R.

2005-01-01

The impact of a mixture of oxytetracycline, chlortetracycline, tetracycline and doxycycline on Myriophyllum sibiricum and Lemna gibba was investigated using fifteen 12,000-L microcosms (k = 5, n = 3). Significant concentration-response relationships were only found for M. sibiricum, where dry mass was 69, 47, 30, and 7% of controls at respective treatment concentrations of 0.080, 0.218, 0.668, and 2.289 μmol/L. Somatic endpoints were strongly and negatively correlated with percent light transmission, except plant length, which was positively correlated. Treated microcosms experienced a reduction in the percent of surface irradiance penetrating the water column as high as 99.8% at a depth of 70 cm, relative to controls. Position relative to the water column was likely responsible for the differential effects observed between floating (L. gibba) and submerged (M. sibiricum) species of macrophytes. A hazard quotient assessment of the lowest EC 10 value indicated significant risk, exceeding the critical HQ value, but not the lowest EC 25 value. - Mixtures of tetracycline antibiotics pose a risk to submerged but not floating aquatic plants

Graphene quantum dots /LaCoO{sub 3}/attapulgite heterojunction photocatalysts with improved photocatalytic activity

Energy Technology Data Exchange (ETDEWEB)

Zhu, Wei; Li, Xiazhang [Changzhou University, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou (China); Chinese Academy of Science, R and D Center of Xuyi Attapulgite Applied Technology, Xuyi (China)

2017-04-15

A new nanocomposite of graphene quantum dots/LaCoO{sub 3}/attapulgite (GQDs/LaCoO{sub 3}/ATP) was prepared by a facile impregnation method and was applied to degradation of the organic pollutants as photocatalyst under visible light irradiation. Multiple techniques were used to characterize the structures, morphologies and photocatalytic activities of samples. The photocatalytic activity of the GQDs/LaCoO{sub 3}/ATP nanocomposites was effectively evaluated using Methylene blue (MB), antibiotic agent chlortetracycline (CHL) and tetracycline hydrochloride (TC). The as-synthesized GQDs/LaCoO{sub 3}/ATP nanocomposites exhibited higher photocatalytic activities than LaCoO{sub 3}/ATP, which showed a broad spectrum of photocatalytic degradation activity. The results of ESR and free radicals trapping experiments indicated that {sup circle} OH and h {sup +} were the main species for the photocatalytic degradation. GQDs played a significant role in the photocatalytic activity improvement of LaCoO{sub 3}/ATP, increasing the visible light absorption, slowing the recombination and improving the charge transfer. (orig.)

Tetracycline compounds with non-antimicrobial organ protective properties: possible mechanisms of action

Science.gov (United States)

Griffin, Michael O.; Ceballos, Guillermo; Villarreal, Francisco

2010-01-01

Tetracyclines were developed as a result of the screening of soil samples for antibiotics. The firstt of these compounds, chlortetracycline, was introduced in 1947. Tetracyclines were found to be highly effective against various pathogens including rickettsiae, as well as both gram-positive and gram-negative bacteria, thus becoming the first class of broad spectrum antibiotics. Many other interesting properties, unrelated to their antibiotic activity, have been identified for tetracyclines which have led to widely divergent experimental and clinical uses. For example, tetracyclines are also an effective anti-malarial drug. Minocycline, which can readily cross cell membranes, is known to be a potent anti-apoptotic agent. Another tetracycline, doxycycline is known to exert anti-protease activities. Doxycycline can inhibit matrix metalloproteinases which contribute to tissue destruction activities in diseases such as periodontitis. A large body of literature has provided additional evidence for the “beneficial” actions of tetracyclines, including their ability to act as reactive oxygen species scavengers and anti-inflammatory agents. This review provides a summary of tetracycline’s multiple mechanisms of action as a means to understand their beneficial effects. PMID:20951211

Effect of anaerobic digestion temperature on odour, coliforms and chlortetracycline in swine manure or monensin in cattle manure

Science.gov (United States)

Antibiotics used in animal feeding operations have been detected in the environment. There is a growing concern about the impact of these pharmaceutical compounds in the manure and the effect they may have on aquatic and terrestrial organisms, and the potential development of antibiotic resistant m...

Performance, health and physiological responses of newly weaned feedlot cattle supplemented with feed-grade antibiotics or alternative feed ingredients.

Science.gov (United States)

de Souza, K A; Cooke, R F; Schubach, K M; Brandão, A P; Schumaher, T F; Prado, I N; Marques, R S; Bohnert, D W

2018-03-26

With increased regulations regarding the use of feed-grade antimicrobials in livestock systems, alternative strategies to enhance growth and immunity of feedlot cattle are warranted. Hence, this experiment compared performance, health and physiological responses of cattle supplemented with feed-grade antibiotics or alternative feed ingredients during the initial 60 days in the feedlot. Angus×Hereford calves (63 steers+42 heifers) originating from two cow-calf ranches were weaned on day -3, obtained from an auction yard on day -2 and road-transported (800 km; 12 h) to the feedlot. Upon arrival on day -1, shrunk BW was recorded. On day 0, calves were ranked by sex, source and shrunk BW, and allocated to one of 21 pens. Pens were assigned to receive (7 pens/treatment) a free-choice total mixed ration containing: (1) lasalocid (360 mg/calf daily of Bovatec; Zoetis, Florham Park, NJ, USA)+chlortetracycline (350 mg/calf of Aureomycin at cycles of 5-day inclusion and 2-day removal from diet; Zoetis) from days 0 to 32, and monensin only (360 mg/calf daily of Rumensin; Elanco Animal Health, Greenfield, IN, USA) from days 33 to 60 (PC), (2) sodium saccharin-based sweetener (Sucram at 0.04 g/kg of diet dry matter; Pancosma SA; Geneva, Switzerland)+plant extracts containing eugenol, cinnamaldehyde and capsicum (800 mg/calf daily of XTRACT Ruminants 7065; Pancosma SA) from days 0 to 32 and XTRACT only (800 mg/calf daily) from days 33 to 60 (EG) or (3) no supplemental ingredients (CON; days 0 to 60). Calves were assessed for bovine respiratory disease (BRD) signs and dry matter intake was recorded from each pen daily. Calves were vaccinated against BRD pathogens on days 0 and 22. Shrunk BW was recorded on day 61, and blood samples collected on days 0, 6, 11, 22, 33, 43 and 60. Calf ADG was greater (P=0.04) in PC v. EG and tended (P=0.09) to be greater in PC v. CON. Feed efficiency also tended (P=0.09) to be greater in PC v. CON, although main treatment effect for this response

Occurrence of pharmaceuticals in a municipal wastewater treatment plant: mass balance and removal processes.

Science.gov (United States)

Gao, Pin; Ding, Yunjie; Li, Hui; Xagoraraki, Irene

2012-06-01

Occurrence and removal efficiencies of fifteen pharmaceuticals were investigated in a conventional municipal wastewater treatment plant in Michigan. Concentrations of these pharmaceuticals were determined in both wastewater and sludge phases by a high-performance liquid chromatograph coupled to a tandem mass spectrometer. Detailed mass balance analysis was conducted during the whole treatment process to evaluate the contributing processes for pharmaceutical removal. Among the pharmaceuticals studied, demeclocycline, sulfamerazine, erythromycin and tylosin were not detected in the wastewater treatment plant influent. Other target pharmaceuticals detected in wastewater were also found in the corresponding sludge phase. The removal efficiencies of chlortetracycline, tetracycline, sulfamerazine, acetaminophen and caffeine were >99%, while doxycycline, oxytetracycline, sulfadiazine and lincomycin exhibited relatively lower removal efficiencies (e.g., <50%). For sulfamethoxazole, the removal efficiency was approximately 90%. Carbamazepine manifested a net increase of mass, i.e. 41% more than the input from the influent. Based on the mass balance analysis, biotransformation is believed to be the predominant process responsible for the removal of pharmaceuticals (22% to 99%), whereas contribution of sorption to sludge was relatively insignificant (7%) for the investigated pharmaceuticals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran.

Science.gov (United States)

Talebiyan, Reza; Kheradmand, Mehdi; Khamesipour, Faham; Rabiee-Faradonbeh, Mohammad

2014-01-01

Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran

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Reza Talebiyan

2014-01-01

Full Text Available Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%, Erythromycin (71.70%, Oxytetracycline (43.40%, Sulfadimethoxine-Trimethoprim (39.62%, Enrofloxacin (37.74%, Florfenicol (35.85%, Chlortetracycline (33.96%, Doxycycline (16.98%, Difloxacin (32.08%, Danofloxacin (28.30%, Chloramphenicol (20.75%, Ciprofloxacin (7.55%, and Gentamicin (5.66%. This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

Mid-infrared spectroscopy and multivariate analysis for determination of tetracycline residues in cow's milk

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Lizeth Mariel Casarrubias-Torres

2018-01-01

Full Text Available Mid-infrared spectroscopy and chemometric analysis were tested to determine tetracycline's residues in cow's milk. Cow's milk samples (n = 30 were spiked with tetracycline, chlortetracycline, and oxytetracycline in the range of 10-400 µg/l. Chemometric models to quantify each of the tetracycline's residues were developed by applying Partial Components Regression and Partial Least Squares algorithms. The Soft Independent Modeling of Class Analogy model was used to differentiate between pure milk and milk sample with tetracycline residues. The best models for predicting the levels of these antibiotics were obtained using Partial Least Square 1 algorithm (coefficient of determination between 0.997-0.999 and the standard error of calibration from 1.81 to 2.95. The Soft Independent Modeling of Class Analogy model showed well-separated groups allowing classification of milk samples and milk sample with antibiotics. The obtained results demonstrate the great analytical potential of chemometrics coupled with mid-infrared spectroscopy for the prediction of antibiotic in cow's milk at a concentration of microgram per litre (µg/l. This technique can be used to verify the safety of the milk rapidly and reliably.

Variations in creatine kinase activity and reactive oxygen species levels are involved in capacitation of bovine spermatozoa.

Science.gov (United States)

Córdoba, M; Pintos, L; Beconi, M T

2008-12-01

The generation of reactive oxygen species (ROS) is associated with some factors such as oxidative substrate sources, mitochondrial function and NAD(P)H oxidase activity. In bovine spermatozoa, heparin capacitation produces a respiratory burst sensitive to diphenyleneiodonium (DPI). Creatine kinase (CK) is related to extramitochondrial ATP disponibility. Our purpose was to determine the variation in ROS level and its relation with NAD(P)H oxidase sensitive to DPI and CK participation, as factors involved in redox state and energy generation in capacitation. The chlortetracycline technique was used to evaluate capacitation. CK activity and ROS level were measured by spectrophotometry and spectrofluorometry respectively. The capacitation percentage was increased by heparin or quercetin treatment (P level as control (238.62 +/- 23.47 arbitrary units per 10(8) spermatozoa) (P > 0.05). CK activity decreased by 50% with heparin or quercetin (P level variations were observed in heparin- or quercetin-treated samples (P bovine spermatozoa, capacitation requires equilibrium between oxidative damage susceptibility and ROS levels. CK activity is associated with redox state variation and energy sources. In conclusion, capacitation induction depends on NADPH oxidase and the shuttle creatine-creatine phosphate, both sensitive to DPI.

In vitro activity of five tetracyclines and some other antimicrobial agents against four porcine respiratory tract pathogens.

Science.gov (United States)

Pijpers, A; Van Klingeren, B; Schoevers, E J; Verheijden, J H; Van Miert, A S

1989-09-01

The minimal inhibitory concentrations (MIC) of five tetracyclines and ten other antimicrobial agents were determined for four porcine bacterial respiratory tract pathogens by the agar dilution method. For the following oxytetracycline-susceptible strains, the MIC50 ranges of the tetracyclines were: P. multocida (n = 17) 0.25-0.5 micrograms/ml; B. bronchiseptica (n = 20) 0.25-1.0 micrograms/ml; H. pleuropneumoniae (n = 20) 0.25-0.5 micrograms/ml; S. suis Type 2 (n = 20) 0.06-0.25 micrograms/ml. For 19 oxytetracycline-resistant P. multocida strains the MIC50 of the tetracyclines varied from 64 micrograms/ml for oxytetracycline to 0.5 micrograms/ml for minocycline. Strikingly, minocycline showed no cross-resistance with oxytetracycline, tetracycline, chlortetracycline and doxycycline in P. multocida and in H. pleuropneumoniae. Moreover, in susceptible strains minocycline showed the highest in vitro activity followed by doxycycline. Low MIC50 values were observed for chloramphenicol, ampicillin, flumequine, ofloxacin and ciprofloxacin against P. multocida and H. pleuropneumoniae. B. bronchiseptica was moderately susceptible or resistant to these compounds. As expected tiamulin, lincomycin, tylosin and spiramycin were not active against H. pleuropneumoniae. Except for flumequine, the MIC50 values of nine antimicrobial agents were low for S. suis Type 2. Six strains of this species showed resistance to the macrolides and lincomycin.

Dietary supplementation with bovine lactoferrampin-lactoferricin produced by Pichia pastoris fed-batch fermentation affects intestinal microflora in weaned piglets.

Science.gov (United States)

Tang, Xiang-Shan; Shao, Hua; Li, Tie-Jun; Tang, Zhi-Ru; Huang, Rui-Ling; Wang, Sheng-Ping; Kong, Xiang-Feng; Wu, Xin; Yin, Yu-Long

2012-10-01

This work is aimed at investigating the effects of recombinant bovine lactoferrampin-lactoferricin (LFA-LFC) instead of chlortetracycline on intestinal microflora in weaned piglets. The high cost of peptide production from either native digestion or chemical synthesis limits the clinical application of antimicrobial peptides. The expression of recombinant peptides in yeast may be an effective alternative. In the current study, recombinant LFA-LFC was produced via fed-batch fermentation in recombinant strain Pichia pastoris (KM71) XS10. Uniform design U6(6(4)) was used to optimize the fermentation conditions. The target peptide purified via cation-exchange and size-exclusion chromatography was added into the dietary of weaned piglets. After 21 days, the Lactobacilli, Bifidobacteria, and Enterobacteria in the chyme of the gut were quantified using real-time polymerase chain reaction. The results showed that approximately 82 mg of LFA-LFC was secreted into 1 L of medium under optimized conditions. Moreover, purified peptide showed strong antimicrobial activities against all the tested microorganisms. Compared with the control group, the LFA-LFC group increased the amount of Lactobacilli and Bifidobacteria (P<0.05) in the chyme of the stomach, duodenum, jejunum, ileum, colon, and caecum. These results show that dietary supplementation with LFA-LFC can affect intestinal microflora in weaned piglets.

Chronic Exposure to Subtherapeutic Antibiotics Aggravates Ischemic Stroke Outcome in Mice

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Xiao-Hui Dong

2017-10-01

Full Text Available Subtherapeutic antibiotics have been widely used in agriculture since the 1950s, which can be accumulated in human body through various approaches and may have long-term consequences. However, there is limited information about the link between chronic subtherapeutic antibiotic exposure and the outcome of ischemic brain injury. Here we showed that long-term treatment with subtherapeutic chlortetracycline, penicillin or vancomycin, which were widely used in agriculture approved by US Food and Drug Administration (FDA, could impair EPC functions, reduce ischemic brain angiogenesis and aggravate cerebral ischemic injury and long-term stroke outcomes in mice. In addition, transplantated EPCs from chronic antibiotic-treated mice showed a lower therapeutic effect on cerebral ischemic injury reduction and local angiogenesis promotion compared to those from control mice, and EPCs from the donor animals could integrate into the recipient ischemic brain in mice. Furthermore, transplanted EPCs might exert paracrine effects on cerebral ischemic injury reduction in mice, which could be impaired by chronic antibiotic exposure. In conclusion, chronic subtherapeutic antibiotic exposure aggravated cerebral ischemic injury in mice, which might be partly attributed to the impairment of both EPC-mediated angiogenesis and EPCs' paracrine effects. These findings reveal a previously unrecognized impact of chronic subtherapeutic antibiotic exposure on ischemic injury.

Long-term antibiotic exposure in soil is associated with changes in microbial community structure and prevalence of class 1 integrons.

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Cleary, David W; Bishop, Alistair H; Zhang, Lihong; Topp, Edward; Wellington, Elizabeth M H; Gaze, William H

2016-10-01

Antimicrobial resistance is one of the most significant challenges facing the global medical community and can be attributed to the use and misuse of antibiotics. This includes use as growth promoters or for prophylaxis and treatment of bacterial infection in intensively farmed livestock from where antibiotics can enter the environment as residues in manure. We characterised the impact of the long-term application of a mixture of veterinary antibiotics alone (tylosin, sulfamethazine and chlortetracycline) on class 1 integron prevalence and soil microbiota composition. Class 1 integron prevalence increased significantly (P Soil microbiota was analysed using 16S rRNA gene sequencing and revealed significant alterations in composition. Of the 19 significantly different (P < 0.05) OTUs identified, 16 were of the Class Proteobacteria and these decreased in abundance relative to the control plots. Only one OTU, of the Class Cyanobacteria, was shown to increase in abundance significantly; a curiosity given the established sensitivity of this class to antibiotics. We hypothesise that the overrepresentation of Proteobacteria as OTUs that decreased significantly in relative abundance, coupled with the observations of an increase in integron prevalence, may represent a strong selective pressure on these taxa. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Antibiotics in the coastal environment of the Hailing Bay region, South China Sea: Spatial distribution, source analysis and ecological risks

International Nuclear Information System (INIS)

Chen, Hui; Liu, Shan; Xu, Xiang-Rong; Zhou, Guang-Jie; Liu, Shuang-Shuang; Yue, Wei-Zhong; Sun, Kai-Feng; Ying, Guang-Guo

2015-01-01

Highlights: • Thirty-eight antibiotics were systematically investigated in marine environment. • The distribution of antibiotics was significantly correlated with COD and NO 3 –N. • Untreated domestic sewage was the primary source of antibiotics. • Fluoroquinolones showed a strong sorption capacity onto sediments. • Oxytetracycline, norfloxacin and erythromycin–H 2 O indicated high risks. - Abstract: In this study, the occurrence and spatial distribution of 38 antibiotics in surface water and sediment samples of the Hailing Bay region, South China Sea, were investigated. Twenty-one, 16 and 15 of 38 antibiotics were detected with the concentrations ranging from <0.08 (clarithromycin) to 15,163 ng/L (oxytetracycline), 2.12 (methacycline) to 1318 ng/L (erythromycin–H 2 O), <1.95 (ciprofloxacin) to 184 ng/g (chlortetracycline) in the seawater, discharged effluent and sediment samples, respectively. The concentrations of antibiotics in the water phase were correlated positively with chemical oxygen demand and nitrate. The source analysis indicated that untreated domestic sewage was the primary source of antibiotics in the study region. Fluoroquinolones showed strong sorption capacity onto sediments due to their high pseudo-partitioning coefficients. Risk assessment indicated that oxytetracycline, norfloxacin and erythromycin–H 2 O posed high risks to aquatic organisms

Simultaneous Determination of TetracyclinesResidues in Bovine Milk Samples by Solid Phase Extraction and HPLC-FL Method

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Mehra Mesgari Abbasi

2011-06-01

Full Text Available Introduction:Tetracyclines (TCs are widely used in animal husbandry and their residues in milk may resultinharmful effects on human. The aim of this study was to investigate the presence of TCs residues in various bovine milk samples from local markets of Ardabil, Iran. Methods:One hundred and fourteen pasteurized, sterilized and raw milk samples were collected from markets of Ardabil. Tetracycline, Oxytetracycline and Chlortetracycline (TCs residues extraction carried out by Solid Phase Extraction method. Determination of TCs residues were performed by high performance liquid chromatography (HPLC method using Fluorescence detector.Results: The mean of total TCs residues in all samples (114 samples was 97.6 ±16.9ng/g and that of pasteurized, sterilized and raw milk samples were 87.1 ± 17.7, 112.0 ± 57.3 and 154.0 ± 66.3ng/g respectively. Twenty five point four percent of the all samples, and24.4%, 30% and 28.6% of the pasteurized, sterilized and raw milk samples, respectively had higher TCs residues than the recommended maximum levels (100ng/g. Conclusion:This study indicates the presence of tetracycline residues more than allowed amount. Regulatory authorities should ensure proper withdrawal period before milking the animals and definite supervisions are necessary on application of these drugs.

Monitoring Antibiotic Residues and Corresponding Antibiotic Resistance Genes in an Agroecosystem

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Yasser M. Awad

2015-01-01

Full Text Available Antibiotic resistance genes (ARGs have been commonly reported due to the overuse worldwide of antibiotics. Antibiotic overuse disturbs the environment and threatens public human health. The objective of this study was to measure the residual concentrations of veterinary antibiotics in the tetracycline group (TCs, including tetracycline (TC and chlortetracycline (CTC, as well as those in the sulfonamide group (SAs, including sulfamethazine (SMT, sulfamethoxazole (SMX, and sulfathiazole (STZ. We also isolated the corresponding ARGs in the agroecosystem. Four sediment samples and two rice paddy soil samples were collected from sites near a swine composting facility along the Naerincheon River in Hongcheon, Korea. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS was employed with a solid-phase extraction method to measure the concentration of each antibiotic. ARGs were identified by the qualitative polymerase chain-reaction using synthetic primers. SAs and their corresponding ARGs were highly detected in sediment samples whereas TCs were not detected except for sediments sample #1. ARGs for TCs and SAs were detected in rice paddy soils, while ARGs for TCs were only found in sediment #2 and #4. Continuous monitoring of antibiotic residue and its comprehensive impact on the environment is needed to ensure environmental health.

Occurrence of Clostridium perfringens contamination in poultry feed ingredients: Isolation, identification and its antibiotic sensitivity pattern

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Shanmugasundaram Udhayavel

2017-09-01

Full Text Available This work has been undertaken to study the occurrence of Clostridium perfringens contamination in the poultry feed ingredients and find out its in-vitro antibiotic sensitivity pattern to various antimicrobial drugs. Two hundred and ninety-eight poultry feed ingredient samples received at Poultry Disease Diagnosis and Surveillance Laboratory, Namakkal, Tamil Nadu in South India were screened for the presence of C. perfringens. The organisms were isolated in Perfringens agar under anaerobic condition and subjected to standard biochemical tests for confirmation. In vitro antibiogram assay has been carried out to determine the sensitivity pattern of the isolates to various antimicrobial drugs. One hundred and one isolates of C. perfringens were obtained from a total of 298 poultry feed ingredient samples. Overall positivity of 33.89% could be made from the poultry feed ingredients. Highest level of C. perfringens contamination was detected in fish meal followed by bone meal, meat and bone meal and dry fish. Antibiogram assay indicated that the organisms are highly sensitive to gentamicin (100%, chlortetracycline (96.67%, gatifloxacin (93.33%, ciprofloxacin (86.67%, ofloxacin (86.67% and lincomycin (86.67%. All the isolates were resistant to penicillin-G. Feed ingredients rich in animal proteins are the major source of C. perfringens contamination.

Spectrophotometric flow-injection analysis assay of tetracycline antibiotics using a dual light-emitting diode based detector

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Prinya Masawat

2008-02-01

Full Text Available In this paper, a small dual light-emitting diode (LED-based detector for FIA process analyser has been designed. The detector’s optical parts comprise a flow-through cell, a dual-blue LED and a photodiode. Neither mirrors nor lenses are used. The optical path for the first LED detects the blank, while the other LED detects the sample. The detector’s electronic components including a signal amplifier and an A/D converter are integrated on one small board connected to a PC for measuring the results. The designed spectrophotometric detector was used for the determination of tetracycline antibiotics. Uranyl acetate was used as a reagent forming orange-red complexes with the drugs in N,N– dimethylformamide. The complexes show absorption maxima at 410, 416 and 408 nm for tetracycline hydrochloride (TCH, chlortetracycline hydrochloride (CTCH, and doxycycline hydrochloride (DCH, respectively. The detection limit was found to be 0.38, 0.75, 1.44 µg mL-1 and the linear range was obtained at 1.0-3.0, 3.0-5.0, and 3.0-10.0 µg mL-1 for TCH, CTCH and DCH, respectively. The proposed method has been successfully applied to the determination of tetracycline antibiotic residues in milk samples. Moreover, this method is an environmentally friendly approach and suitable for routine analysis.

Prioritisation of veterinary medicines in the UK environment.

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Boxall, Alistair B A; Fogg, Lindsay A; Kay, Paul; Blackwel, Paul A; Pemberton, Emma J; Croxford, Andy

2003-05-15

A wide range of veterinary medicines is used to treat animals in the UK. Whilst the environmental impact of selected substances (particulary the sheep dip chemicals, anthelmintics and fish farm chemicals) has been well studied, limited information is available in the public domain on the other groups of substances (e.g. antifungals, coccidiostats, antiprotozoals, hormones and growth promoters). There is therefore a need to identify other substances that may impact the environment in order to design national monitoring programmes, target experimental work and develop pollution prevention methodologies. In this study, a simple two-stage prioritisation scheme was developed and applied to veterinary medicines in use in the UK. In the first stage, those substances that have high potential to enter the environment in significant amounts were identified on the basis of amounts used in the UK, treatment type and metabolism. In stage 2, the hazard of the identified substances to terrestrial and aquatic organisms was assessed. Using the approach, a total of 56 substances or groups were assigned to a 'high priority' category. For eleven of these substances, sufficient data were available to characterise their risk, these were: oxytetracycline, chlortetracycline, tetracycline, sulphadiazine, amoxicillin, diazinon, tylosin, dihydrostreptomycin, apramycin, cypermethrin and sarafloxicin. For the remaining 45 substances, full datasets were not available and it is recommended that in the first instance, attempts are made to fill these data gaps.

Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

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Liu, Ping; Soupir, Michelle L.; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

2011-01-01

Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms. PMID:21821756

Association of antibiotic resistance in agricultural Escherichia coli isolates with attachment to quartz.

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Liu, Ping; Soupir, Michelle L; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R

2011-10-01

Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms.

Membrane status and in vitro capacitation of porcine sperm preserved in long-term extender at 16 degrees C.

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Conejo-Nava, J; Fierro, R; Gutierrez, C G; Betancourt, M

2003-01-01

Preservation of porcine semen in long-term extenders at 15-18 degrees C for more than 5 days results in decreased farrowing rates and reduced litter size after artificial insemination, despite the high progressive motility rates of sperm. To improve this preservation system it is necessary to understand sperm physiology under storage conditions. The purpose of this study was to determine the effect of storing diluted porcine semen (during 0, 2, 4, 6, and 8 days) on the sperm membranes status and the ability of sperm to respond to in vitro capacitation treatment. Ten semen samples from 5 adult boars were analyzed. Two aliquots were obtained from the sperm-rich fraction: one was used to assess fresh semen and the other was diluted in Reading extender and stored at 16 degrees C. Both semen samples were stained with chlortetracycline to assess the status of sperm membranes and with Hoechst 33258 to determine viability. Semen storage for 4-8 days increased the proportion of prematurely capacitated sperm. After 4 days of storage, in vitro capacitation treatment did not increase the percentage of capacitated sperm, but increased the percentage of acrosome reacted sperm. This phenomenon could explain the reduced fertilizing ability of porcine semen stored at 16 degrees C for over 4 days, in spite of the acceptable sperm viability and progressive motility.

Tetracycline removal from water by adsorption/bioadsorption on activated carbons and sludge-derived adsorbents.

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Rivera-Utrilla, José; Gómez-Pacheco, Carla V; Sánchez-Polo, Manuel; López-Peñalver, Jesús J; Ocampo-Pérez, Raúl

2013-12-15

The objective of this study was to analyze the behavior of activated carbons with different chemical and textural natures in the adsorption of three tetracyclines (TCs) (tetracycline, oxytetracycline, and chlortetracycline). We also assessed the influence of the solution pH and ionic strength on the adsorption of these compounds and studied their removal by the combined use of microorganisms and activated carbon (bioadsorption). Sludge-derived materials were also used to remove TC from water. The capacity of these materials to adsorb TC was very high and was much greater than that of commercial activated carbon. This elevated adsorption capacity (512.1-672.0 mg/g) is explained by the high tendency of TC to form complex ions with some of the metal ions present in these materials. The medium pH and presence of electrolytes considerably affected TCs adsorption on commercial activated carbon. These results indicate that electrostatic adsorbent-adsorbate interactions play an important role in TC adsorption processes when conducted at pH values that produce TC deprotonation. The presence of bacteria during the TCs adsorption process decreases their adsorption/bioadsorption on the commercial activated carbon, weakening interactions between the adsorbate and the microfilm formed on the carbon surface. The adsorptive capacity was considerably lower in dynamic versus static regime, attributable to problems of TC diffusion into carbon pores and the shorter contact time between adsorbate and adsorbent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Collateral Effects of Antibiotics: Carbadox and Metronidazole Induce VSH-1 and Facilitate Gene Transfer among Brachyspira hyodysenteriae Strains▿

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Stanton, Thaddeus B.; Humphrey, Samuel B.; Sharma, Vijay K.; Zuerner, Richard L.

2008-01-01

Brachyspira hyodysenteriae is an anaerobic spirochete and the etiologic agent of swine dysentery. The genome of this spirochete contains a mitomycin C-inducible, prophage-like gene transfer agent designated VSH-1. VSH-1 particles package random 7.5-kb fragments of the B. hyodysenteriae genome and transfer genes between B. hyodysenteriae cells. The chemicals and conditions inducing VSH-1 production are largely unknown. Antibiotics used in swine management and stressors inducing traditional prophages might induce VSH-1 and thereby stimulate lateral gene transfer between B. hyodysenteriae cells. In these studies, VSH-1 induction was initially detected by a quantitative real-time reverse transcriptase PCR assay evaluating increased transcription of hvp38 (VSH-1 head protein gene). VSH-1 induction was confirmed by detecting VSH-1-associated 7.5-kb DNA and VSH-1 particles in B. hyodysenteriae cultures. Nine antibiotics (chlortetracycline, lincomycin, tylosin, tiamulin, virginiamycin, ampicillin, ceftriaxone, vancomycin, and florfenicol) at concentrations affecting B. hyodysenteriae growth did not induce VSH-1 production. By contrast, VSH-1 was detected in B. hyodysenteriae cultures treated with mitomycin C (10 μg/ml), carbadox (0.5 μg/ml), metronidazole (0.5 μg/ml), and H2O2 (300 μM). Carbadox- and metronidazole-induced VSH-1 particles transmitted tylosin and chloramphenicol resistance determinants between B. hyodysenteriae strains. The results of these studies suggest that certain antibiotics may induce the production of prophage or prophage-like elements by intestinal bacteria and thereby impact intestinal microbial ecology. PMID:18359835

In-feed antibiotic effects on the swine intestinal microbiome

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Looft, Torey; Johnson, Timothy A.; Allen, Heather K.; Bayles, Darrell O.; Alt, David P.; Stedtfeld, Robert D.; Sul, Woo Jun; Stedtfeld, Tiffany M.; Chai, Benli; Cole, James R.; Hashsham, Syed A.; Tiedje, James M.; Stanton, Thad B.

2012-01-01

Antibiotics have been administered to agricultural animals for disease treatment, disease prevention, and growth promotion for over 50 y. The impact of such antibiotic use on the treatment of human diseases is hotly debated. We raised pigs in a highly controlled environment, with one portion of the littermates receiving a diet containing performance-enhancing antibiotics [chlortetracycline, sulfamethazine, and penicillin (known as ASP250)] and the other portion receiving the same diet but without the antibiotics. We used phylogenetic, metagenomic, and quantitative PCR-based approaches to address the impact of antibiotics on the swine gut microbiota. Bacterial phylotypes shifted after 14 d of antibiotic treatment, with the medicated pigs showing an increase in Proteobacteria (1–11%) compared with nonmedicated pigs at the same time point. This shift was driven by an increase in Escherichia coli populations. Analysis of the metagenomes showed that microbial functional genes relating to energy production and conversion were increased in the antibiotic-fed pigs. The results also indicate that antibiotic resistance genes increased in abundance and diversity in the medicated swine microbiome despite a high background of resistance genes in nonmedicated swine. Some enriched genes, such as aminoglycoside O-phosphotransferases, confer resistance to antibiotics that were not administered in this study, demonstrating the potential for indirect selection of resistance to classes of antibiotics not fed. The collateral effects of feeding subtherapeutic doses of antibiotics to agricultural animals are apparent and must be considered in cost-benefit analyses. PMID:22307632

Antimicrobial resistance trends among Escherichia coli isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

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Cummings, Kevin J; Aprea, Victor A; Altier, Craig

2014-01-01

Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform risk analyses and guide public policy regarding antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Escherichia coli isolates from dairy cattle in the northeastern United States and to identify trends in resistance to selected antimicrobial agents over time. We collected data retrospectively for all bovine E. coli isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. We investigated temporal trends in the prevalence of resistant E. coli for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 3373 bovine E. coli isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 2.7% (enrofloxacin) to 91.3% (oxytetracycline). There was evidence of a significantly decreasing trend in prevalence of resistance to several agents: chlortetracycline, florfenicol, neomycin, oxytetracycline, spectinomycin, and trimethoprim/sulfamethoxazole. However, a significantly increasing trend in prevalence of resistance to enrofloxacin was also evident. These results do not support the idea that current antimicrobial use practices on dairy operations are driving a general increase in the emergence and dissemination of drug-resistant E. coli in the region served by the laboratory. However, resistance to some drugs remained consistently high during the study period, and increasing resistance to enrofloxacin is a key area of concern.

Planar chromatography mediated screening of tetracycline and fluoroquinolone antibiotics in milk by fluorescence and mass selective detection.

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Chen, Yisheng; Schwack, Wolfgang

2013-10-18

A rapid and efficient method for preliminary screening of four tetracyclines (tetracycline, chlortetracycline, oxytetracycline, doxycline) and three fluoroquinolones (enrofloxacin, ciprofloxacin, marbofloxacin), mostly detected in milk, by high-performance thin-layer chromatography-fluorescence detection and electrospray ionization mass spectrometry (HPTLC-FLD-ESI/MS) is highlighted. The optimized separation of the target antibiotics on ethylenediamine tetraacetic acid modified silica gel plates showed marked benefits for screening purposes. Besides, selective and sensitive densitometry in fluorescence mode was established with excitation at 366nm for the tetracyclines, 300nm for enrofloxacin and ciprofloxacin, and 280nm for marbofloxacin. Limits of detection (LOD) and quantitation (LOQ) with 95% confidence were in the range of 12-25 and 45-95μg/kg, respectively, in milk samples. Recoveries of target antibiotics from milk samples spiked at three critical levels (50, 100 and 150μg/kg) ranged from 76% to 105%. More importantly, a mass selective detection (MSD) was established as additional tool for confirmatory purposes. Using the elution-head based TLC-MS interface, the optimized elution flow consisting of acetonitrile/ammonium formate buffer (9/1, v/v) at a rate of 0.3mL/min enabled time-dependent resolution of analytes from the major interfering compounds, thus circumventing serious ion suppression effects. The established MSD assay also offered high sensitivity (25μg/kg) for confirmation, meeting Commission Regulation (EU) No. 37/2010. Copyright © 2013 Elsevier B.V. All rights reserved.

A reversed-phase high performance liquid chromatography coupled with resonance Rayleigh scattering detection for the determination of four tetracycline antibiotics

International Nuclear Information System (INIS)

Wang Lifeng; Peng Jingdong; Liu Limin

2008-01-01

A new reversed-phase high performance liquid chromatography with resonance Rayleigh scattering detection (HPLC-RRS) was developed for simultaneous separation and determination of four tetracycline antibiotics (TCs). A good chromatographic separation among the compounds was achieved using a Synergi Fusion-RP column (150 mm x 4.6 mm; 4 μm) and a mobile phase consisting of methanol-acetonitrile-oxalic acid (5 mM) at the flow rate of 0.8 mL min -1 . Column temperature was 30 deg. C. The RRS signal was detected at λ ex = λ em = 370 nm. The recoveries of sample added standard ranged from 95.3% to 103.5%, and the relative standard deviation was below 2.79%. A detection limit of 2.12-5.12 μg mL -1 was reached and a linear range was found between peak height and concentration in the range of 10.36-518.0 μg mL -1 for oxytetracycline (OTC), 12.11-605.5 μg mL -1 for tetracycline (TC), 11.79-589.5 μg mL -1 for chlortetracycline (CTC) and 10.32-516.0 μg mL -1 for doxycycline (DC). The linear regression coefficients were all above 0.999. The method has been applied successfully to the determination of OTC, TC, CTC, DC in pharmaceutical formulations and in honey. The method was simple, rapid and showed a better linear relation and high repeatability

A reversed-phase high performance liquid chromatography coupled with resonance Rayleigh scattering detection for the determination of four tetracycline antibiotics

Energy Technology Data Exchange (ETDEWEB)

Lifeng, Wang [School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Peng Jingdong [School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)], E-mail: hxpengjd@swu.edu.cn; Limin, Liu [School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

2008-12-07

A new reversed-phase high performance liquid chromatography with resonance Rayleigh scattering detection (HPLC-RRS) was developed for simultaneous separation and determination of four tetracycline antibiotics (TCs). A good chromatographic separation among the compounds was achieved using a Synergi Fusion-RP column (150 mm x 4.6 mm; 4 {mu}m) and a mobile phase consisting of methanol-acetonitrile-oxalic acid (5 mM) at the flow rate of 0.8 mL min{sup -1}. Column temperature was 30 deg. C. The RRS signal was detected at {lambda}{sub ex} = {lambda}{sub em} = 370 nm. The recoveries of sample added standard ranged from 95.3% to 103.5%, and the relative standard deviation was below 2.79%. A detection limit of 2.12-5.12 {mu}g mL{sup -1} was reached and a linear range was found between peak height and concentration in the range of 10.36-518.0 {mu}g mL{sup -1} for oxytetracycline (OTC), 12.11-605.5 {mu}g mL{sup -1} for tetracycline (TC), 11.79-589.5 {mu}g mL{sup -1} for chlortetracycline (CTC) and 10.32-516.0 {mu}g mL{sup -1} for doxycycline (DC). The linear regression coefficients were all above 0.999. The method has been applied successfully to the determination of OTC, TC, CTC, DC in pharmaceutical formulations and in honey. The method was simple, rapid and showed a better linear relation and high repeatability.

Direct and indirect fluorescent detection of tetracyclines using dually emitting carbon dots

International Nuclear Information System (INIS)

Qu, Fei; Sun, Zhe; Liu, Dongya; Zhao, Xianen; You, Jinmao

2016-01-01

The authors describe dual-emission carbon nanodots containing blue emitters (BE; peak emission at 385 nm under 315 nm excitation) and yellow emitters (YE; peak emission at 530 nm under 365 nm excitation), and how they can be applied to direct and indirect determination of tetracyclines (TCs). The direct detection scheme is based on the finding that tetracycline (TET), oxytetracycline, chlortetracycline and doxycycline quench the two emissions of the carbon dots. While direct determination is rapid and convenient, it cannot differentiate between TCs. The indirect detection scheme, in contrast, is based on the finding that Al (III) ions enhance the fluorescence of the YE in the carbon dots, and that they cause a blue shift in emission. It is, however, known that TET forms a strong complex with Al (III), and this can inhibit the interaction between Al (III) and the YE, so that the fluorescence of YE is not enhanced and blue-shifted by Al (III) in the presence of TET. This finding is exploited in a fluorescence turn-on/off assay for TET that can distinguish TET from other TCs. The linear range of indirect determination for TET extends from 1 nM to 30 μM, and the limit of detection is 0.52 nM. The indirect method was successfully applied to the determination of TET in spiked milk, fish and pork, and recoveries ranged from 91.7 to 102 %. (author)

Biosynthesis of Oxytetracycline by Streptomyces rimosus: Past, Present and Future Directions in the Development of Tetracycline Antibiotics

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Hrvoje Petković

2017-01-01

Full Text Available Natural tetracycline (TC antibiotics were the first major class of therapeutics to earn the distinction of ‘broad-spectrum antibiotics’ and they have been used since the 1940s against a wide range of both Gram-positive and Gram-negative pathogens, mycoplasmas, intracellular chlamydiae, rickett siae and protozoan parasites. The second generation of semisynthetic tetracyclines, such as minocycline and doxycycline, with improved antimicrobial potency, were introduced during the 1960s. Despite emerging resistance to TCs erupting during the 1980s, it was not until 2006, more than four decades later, that a third-generation TC, named tigecycline, was launched. In addition, two TC analogues, omadacycline and eravacycline, developed via (semisynthetic and fully synthetic routes, respectively, are at present under clinical evaluation. Interestingly, despite very productive early work on the isolation of a Streptomyces aureofaciens mutant strain that produced 6-demethyl-7-chlortetracycline, the key intermediate in the production of second- and third-generation TCs, biosynthetic approaches in TC development have not been productive for more than 50 years. Relatively slow and tedious molecular biology approaches for the genetic manipulation of TC-producing actinobacteria, as well as an insufficient understanding of the enzymatic mechanisms involved in TC biosynthesis have significantly contributed to the low success of such biosynthetic engineering efforts. However, new opportunities in TC drug development have arisen thanks to a signifi cant progress in the development of affordable and versatile biosynthetic engineering and synthetic biology approaches, and, importantly, to a much deeper understanding of TC biosynthesis, mostly gained over the last two decades.

Bacteria, phages and pigs: the effects of in-feed antibiotics on the microbiome at different gut locations.

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Looft, Torey; Allen, Heather K; Cantarel, Brandi L; Levine, Uri Y; Bayles, Darrell O; Alt, David P; Henrissat, Bernard; Stanton, Thaddeus B

2014-08-01

Disturbance of the beneficial gut microbial community is a potential collateral effect of antibiotics, which have many uses in animal agriculture (disease treatment or prevention and feed efficiency improvement). Understanding antibiotic effects on bacterial communities at different intestinal locations is essential to realize the full benefits and consequences of in-feed antibiotics. In this study, we defined the lumenal and mucosal bacterial communities from the small intestine (ileum) and large intestine (cecum and colon) plus feces, and characterized the effects of in-feed antibiotics (chlortetracycline, sulfamethazine and penicillin (ASP250)) on these communities. 16S rRNA gene sequence and metagenomic analyses of bacterial membership and functions revealed dramatic differences between small and large intestinal locations, including enrichment of Firmicutes and phage-encoding genes in the ileum. The large intestinal microbiota encoded numerous genes to degrade plant cell wall components, and these genes were lacking in the ileum. The mucosa-associated ileal microbiota harbored greater bacterial diversity than the lumen but similar membership to the mucosa of the large intestine, suggesting that most gut microbes can associate with the mucosa and might serve as an inoculum for the lumen. The collateral effects on the microbiota of antibiotic-fed animals caused divergence from that of control animals, with notable changes being increases in Escherichia coli populations in the ileum, Lachnobacterium spp. in all gut locations, and resistance genes to antibiotics not administered. Characterizing the differential metabolic capacities and response to perturbation at distinct intestinal locations will inform strategies to improve gut health and food safety.

Quantifying Attachment and Antibiotic Resistance of from Conventional and Organic Swine Manure.

Science.gov (United States)

Zwonitzer, Martha R; Soupir, Michelle L; Jarboe, Laura R; Smith, Douglas R

2016-03-01

Broad-spectrum antibiotics are often administered to swine, contributing to the occurrence of antibiotic-resistant bacteria in their manure. During land application, the bacteria in swine manure preferentially attach to particles in the soil, affecting their transport in overland flow. However, a quantitative understanding of these attachment mechanisms is lacking, and their relationship to antibiotic resistance is unknown. The objective of this study is to examine the relationships between antibiotic resistance and attachment to very fine silica sand in collected from swine manure. A total of 556 isolates were collected from six farms, two organic and four conventional (antibiotics fed prophylactically). Antibiotic resistance was quantified using 13 antibiotics at three minimum inhibitory concentrations: resistant, intermediate, and susceptible. Of the 556 isolates used in the antibiotic resistance assays, 491 were subjected to an attachment assay. Results show that isolates from conventional systems were significantly more resistant to amoxicillin, ampicillin, chlortetracycline, erythromycin, kanamycin, neomycin, streptomycin, tetracycline, and tylosin ( < 0.001). Results also indicate that isolated from conventional systems attached to very fine silica sand at significantly higher levels than those from organic systems ( < 0.001). Statistical analysis showed that a significant relationship did not exist between antibiotic resistance levels and attachment in from conventional systems but did for organic systems ( < 0.001). Better quantification of these relationships is critical to understanding the behavior of in the environment and preventing exposure of human populations to antibiotic-resistant bacteria. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Residues of pharmaceutical products in recycled organic manure produced from sewage sludge and solid waste from livestock and relationship to their fermentation level.

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Motoyama, Miki; Nakagawa, Shuhei; Tanoue, Rumi; Sato, Yuri; Nomiyama, Kei; Shinohara, Ryota

2011-07-01

In recent years, sludge generated in sewage treatment plants (STPs) and solid waste from livestock being utilized is useful for circulation of nourishment in farmlands as recycled organic manure (ROM). In this study, we determined the residue levels and patterns of 12 pharmaceutical products generated by human activity in the ROMs produced from human waste sludge (HWS), sewage sludge (SS), cattle manure (CM), poultry manure (PM), swine manure (SM) and horse manure (HM). The kind and number of pharmaceutical products detected in ROMs were different. Fluoroquinolones (FQs) were detected at high levels in HWS and SS samples. In addition, the detection frequency and concentration levels of sulfonamides (SAs) in PM and SM were high. Moreover, high concentrations of chlortetracycline (CTC) were found in only SM. These differences reflect specific adherence adsorption of the pharmaceutical products to different livestock and humans. Moreover, it was found that the concentrations of pharmaceutical products and fermentation levels of ROMs had significant positive correlation (r=0.41, p=0.024). When the fermentation test of ROM was conducted in a rotary fermentor in a lab scale test, the residue levels of pharmaceutical products decreased effectively except carbamazepine (CBZ). The rates of decrease were in the case of tetracyclines (TCs): 85-92%, FQs: 81-100%, erythromycine: 67%, SAs: 79-95%, trimethoprim: 86% and CBZ: 37% by 30 d. Pharmaceutical products that can be decomposed by fermentation process at the lowest impact of residual antibiotic activities may therefore be considered as environmentally friendly medicines. Copyright © 2011 Elsevier Ltd. All rights reserved.

Assessment of sperm viability, mitochondrial activity, capacitation and acrosome intactness in extended boar semen during long-term storage.

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Huo, Li-Jun; Ma, Xing-Hong; Yang, Zeng-Ming

2002-10-15

The purpose of this study was to assess sperm quality in extended boar semen during in vitro storage in order to determine which extender should be used and how long boar semen can be stored. Freshly ejaculated boar semen was diluted with equal volumes of Beltsville thaw solution (BTS), Androhep, KIEV or Zorlesco extenders and stored at 17 degrees C for up to 15 days. Sperm quality was evaluated by examining viability using SYBR-14/PI and Hoechst 33258 staining, mitochondrial activity using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) staining, acrosome intactness by Coomassie blue staining, and capacitation status by chlortetracycline (CTC) staining. There were over 50% viable spermatozoa in boar semen extended with Zorlesco and Androhep extenders on Day 13 of storage. The percentage of JC-1-stained spermatozoa was 53.8 +/- 2.1% for Zorlesco and 57.7 +/- 1.60% for Androhep extenders on Day 13 of storage. The percentage of acrosome-intact spermatozoa detected by Coomassie blue staining was higher than that in the SYBR-14PI-, Hoechst 33258-, and JC-1-stained samples in our study. The results from SYBR-14/PI, Hoechst 33258, JC-1, and Coomassie blue staining were highly correlated (r > or = 0.9461). There were less than 15% capacitated spermatozoa in the semen extended with BTS, Androhep and Zorlesco extenders during 9 days of storage. However, most viable boar spermatozoa became capacitated by Day 13 of storage. The rank order of four extenders for maintaining sperm viability and mitochondrial activity was as follows: Androhep, Zorlesco, BTS, KIEV.

Performance of blue-yellow screening test for antimicrobial detection in ovine milk.

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Linage, B; Gonzalo, C; Carriedo, J A; Asensio, J A; Blanco, M A; De La Fuente, L F; San Primitivo, F

2007-12-01

Drug residues in milk are important because of public health and industrial implications. The detection limits of 25 antimicrobial agents were determined by the blue-yellow screening method in ovine milk. For each drug, 8 concentrations were tested on 20 ovine milk samples from individual ewes in midlactation. Detection limits determined by means of logistic regression were below European Union maximum residue limits (EU-MRL) for penicillin G (3 to 4 microg/kg), ceftiofur (96 to 107 microg/kg), framycetin (720 to 781 microg/kg), neomycin (915 to 1,084 microg/kg), and tylosin (44 to 51 microg/kg). Detection limits for ampicillin (5 to 6 microg/kg), cloxacillin (33 to 42 microg/kg), cefoperazone (73 to 82 microg/kg), cefalexin (160 to 202 microg/kg), gentamycin (355 to 382 microg/kg), streptomycin (3,063 to 3,593 microg/kg), tilmicosin (109 to 131 microg/kg), erythromycin (444 to 522 microg/kg), spyramicin (1,106 to 1,346 microg/kg), sulfadimethoxine (101 to 119 microg/kg), sulfathiazole (122 to 151 microg/kg), sulfamethazine (309 to 328 microg/kg), sulfanilamide (1,750 to 2,674 microg/kg), tetracycline (233 to 257 microg/kg), oxytetracycline (398 to 501 microg/kg), doxycycline (323 to 419 microg/kg), chlortetracycline (3,331 to 3,989 microg/kg), danofloxacin (4.7 to 5.5 mg/kg), enrofloxacin (41 to 46 mg/kg), and flumequin (63 to 71 mg/kg) were higher than the EU-MRL. Although the blue-yellow method showed improved sensitivity compared with other tests studied in ovine milk, the performance of screening methods for detecting antimicrobial agents in milk of this species should be improved.

Enhanced in vitro activity of tigecycline in the presence of chelating agents.

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Deitchman, Amelia N; Singh, Ravi Shankar Prasad; Rand, Kenneth H; Derendorf, Hartmut

2018-05-01

The lack of availability of novel antibiotic agents and the rise of resistance to existing therapies has led clinicians to utilise combination therapy to adequately treat bacterial infections. Here we examined how chelators may impact the in vitro activity of tigecycline (TIG) against Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Minimum inhibitory concentrations (MICs) were determined by broth dilution with and without various combinations of chelators (EDTA and other tetracyclines) and metal ions (i.e. calcium, magnesium). Trimethoprim (TMP) was used as a non-chelating control. Addition of metal ions led to increases in MICs, whilst addition of EDTA led to decreases in MICs. The chelating effects of EDTA were reversed by addition of magnesium and most profoundly calcium. Similar effects of EDTA and calcium were observed for tetracycline (TET) and TMP. When other tetracyclines (TET, oxytetracycline (OXY) and chlortetracycline (CHL)) were used as chelators at concentrations below their MICs, TIG MICs decreased for P. aeruginosa but not for E. coli. Some decreases in TIG MICs were observed for K. pneumoniae when TET and CHL were added. A dose-dependent decrease in TIG MIC was observed for TET and was reversed by the addition of calcium. The presence of effects of EDTA and calcium on TMP MICs indicates that mechanisms outside of TIG chelation likely play a role in enhanced activity. Full characterisation of an unexpected interaction such as TIG-TET with different microorganisms could provide valuable insights into the underlying mechanisms and design of physiologically viable chelators as candidates for future combinations regimens. Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Degradation of Tetracyclines in Pig Manure by Composting with Rice Straw

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Chai, Rushan; Huang, Lidong; Li, Lingling; Gielen, Gerty; Wang, Hailong; Zhang, Yongsong

2016-01-01

A holistic approach was followed for utilizing tetracyclines (TCs)-contaminated pig manure, by composting this with rice straw in a greenhouse for CO2 fertilization and composted residue application. After composting, the composted residues can be applied to cropland as a supplemental source of synthetic fertilizers. The objective of this study was to determine the effect of pig manure-rice straw composting on the degradation of TCs in pig manure. The results showed that greenhouse composting significantly accelerated the degradation of TCs. Contents (150 mg·kg−1) of oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) in the composting feedstock could be completely removed within 42 days for OTC and TC, and 14 days for CTC. However, in the control samples incubated at 25 °C in the dark, concentrations of OTC, TC and CTC only decreased 64.7%, 66.7% and 73.3%, respectively, after 49 days. The degradation rates of TCs in the composting feedstock were in the order of CTC > TC > OTC. During the composting process, CTC dissipated rapidly with the time required for 50% degradation (DT50) and 90% degradation (DT90) of 2.4 and 7.9 days, but OTC was more persistent with DT50 and DT90 values of 5.5 and 18.4 days. On the basis of the results obtained in this study, it could be concluded that pig manure-rice straw composting in a greenhouse can help to accelerate the degradation of TCs in pig manure and make composted residues safer for field application. This technology could be an acceptable practice for greenhouse farmers to utilize TCs-contaminated pig manure. PMID:26927136

Administration of probiotics influences F4 (K88-positive enterotoxigenic Escherichia coli attachment and intestinal cytokine expression in weaned pigs

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Daudelin Jean-François

2011-05-01

Full Text Available Abstract This study evaluated the effect of the probiotics Pediococcus acidilactici and Saccharomyces cerevisiae boulardii on the intestinal colonization of O149 enterotoxigenic Escherichia coli harbouring the F4 (K88 fimbriae (ETEC F4 and on the expression of ileal cytokines in weaned pigs. At birth, different litters of pigs were randomly assigned to one of the following treatments: 1 control without antibiotics or probiotics (CTRL; 2 reference group in which chlortetracycline and tiamulin were added to weanling feed (ATB; 3 P. acidilactici; 4 S. cerevisiae boulardii; or 5 P. acidilactici + S. cerevisiae boulardii. Probiotics were administered daily (1 × 109 CFU per pig during the lactation period and after weaning (day 21. At 28 days of age, all pigs were orally challenged with an ETEC F4 strain, and a necropsy was performed 24 h later. Intestinal segments were collected to evaluate bacterial colonization in the small intestine and ileal cytokine expressions. Attachment of ETEC F4 to the intestinal mucosa was significantly reduced in pigs treated with P. acidilactici or S. cerevisiae boulardii in comparison with the ATB group (P = 0.01 and P = 0.03, respectively. In addition, proinflammatory cytokines, such as IL-6, were upregulated in ETEC F4 challenged pigs treated with P. acidilactici alone or in combination with S. cerevisiae boulardii compared with the CTRL group. In conclusion, the administration of P. acidilactici or S. cerevisiae boulardii was effective in reducing ETEC F4 attachment to the ileal mucosa, whereas the presence of P. acidilactici was required to modulate the expression of intestinal inflammatory cytokines in pigs challenged with ETEC F4.

Administration of probiotics influences F4 (K88)-positive enterotoxigenic Escherichia coli attachment and intestinal cytokine expression in weaned pigs.

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Daudelin, Jean-François; Lessard, Martin; Beaudoin, Frédéric; Nadeau, Eric; Bissonnette, Nathalie; Boutin, Yvan; Brousseau, Jean-Philippe; Lauzon, Karoline; Fairbrother, John Morris

2011-05-23

This study evaluated the effect of the probiotics Pediococcus acidilactici and Saccharomyces cerevisiae boulardii on the intestinal colonization of O149 enterotoxigenic Escherichia coli harbouring the F4 (K88) fimbriae (ETEC F4) and on the expression of ileal cytokines in weaned pigs. At birth, different litters of pigs were randomly assigned to one of the following treatments: 1) control without antibiotics or probiotics (CTRL); 2) reference group in which chlortetracycline and tiamulin were added to weanling feed (ATB); 3) P. acidilactici; 4) S. cerevisiae boulardii; or 5) P. acidilactici + S. cerevisiae boulardii. Probiotics were administered daily (1 × 10(9) CFU per pig) during the lactation period and after weaning (day 21). At 28 days of age, all pigs were orally challenged with an ETEC F4 strain, and a necropsy was performed 24 h later. Intestinal segments were collected to evaluate bacterial colonization in the small intestine and ileal cytokine expressions. Attachment of ETEC F4 to the intestinal mucosa was significantly reduced in pigs treated with P. acidilactici or S. cerevisiae boulardii in comparison with the ATB group (P = 0.01 and P = 0.03, respectively). In addition, proinflammatory cytokines, such as IL-6, were upregulated in ETEC F4 challenged pigs treated with P. acidilactici alone or in combination with S. cerevisiae boulardii compared with the CTRL group. In conclusion, the administration of P. acidilactici or S. cerevisiae boulardii was effective in reducing ETEC F4 attachment to the ileal mucosa, whereas the presence of P. acidilactici was required to modulate the expression of intestinal inflammatory cytokines in pigs challenged with ETEC F4.

A Drug Combination Screen Identifies Drugs Active against Amoxicillin-induced Round Bodies of Borrelia burgdorferi Persisters from an FDA Drug Library

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Jie eFeng

2016-05-01

Full Text Available Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10-20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that are not killed by current Lyme antibiotics. To identify more effective drugs that are active against the round bodies of B. burgdorferi, we established a round body persister model induced by amoxicillin and screened the Food and Drug Administration (FDA drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide (PI viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven of these scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. While some drug candidates such as daptomycin and clofazimine overlapped with a previous screen against stationary phase B. burgdorferi persisters, additional drug candidates active against round bodies we identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi persisters in vitro, even if pre-treated with amoxicillin. These findings may have implications for improved treatment of Lyme disease.

Use of generalized ordered logistic regression for the analysis of multidrug resistance data.

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Agga, Getahun E; Scott, H Morgan

2015-10-01

Statistical analysis of antimicrobial resistance data largely focuses on individual antimicrobial's binary outcome (susceptible or resistant). However, bacteria are becoming increasingly multidrug resistant (MDR). Statistical analysis of MDR data is mostly descriptive often with tabular or graphical presentations. Here we report the applicability of generalized ordinal logistic regression model for the analysis of MDR data. A total of 1,152 Escherichia coli, isolated from the feces of weaned pigs experimentally supplemented with chlortetracycline (CTC) and copper, were tested for susceptibilities against 15 antimicrobials and were binary classified into resistant or susceptible. The 15 antimicrobial agents tested were grouped into eight different antimicrobial classes. We defined MDR as the number of antimicrobial classes to which E. coli isolates were resistant ranging from 0 to 8. Proportionality of the odds assumption of the ordinal logistic regression model was violated only for the effect of treatment period (pre-treatment, during-treatment and post-treatment); but not for the effect of CTC or copper supplementation. Subsequently, a partially constrained generalized ordinal logistic model was built that allows for the effect of treatment period to vary while constraining the effects of treatment (CTC and copper supplementation) to be constant across the levels of MDR classes. Copper (Proportional Odds Ratio [Prop OR]=1.03; 95% CI=0.73-1.47) and CTC (Prop OR=1.1; 95% CI=0.78-1.56) supplementation were not significantly associated with the level of MDR adjusted for the effect of treatment period. MDR generally declined over the trial period. In conclusion, generalized ordered logistic regression can be used for the analysis of ordinal data such as MDR data when the proportionality assumptions for ordered logistic regression are violated. Published by Elsevier B.V.

Irradiation studies of local Streptomyces strains for higher antibiotic producing capacity. Part of a coordinated programme on radiation microbiology

International Nuclear Information System (INIS)

Kintanar, Q.L.

1978-06-01

The 14 mutants produced by sequential exposure to gamma and ultraviolet irradiation were found to belong to different fundamental types of variants differing in morphology, stability, and metabolite spectra from the parent strain. The first hour mutants, M-1 to M-4 could be considered as belonging to the first category of mutants. Metabolites produced were the same as the parent but differ only in quantity. One was a morphological mutant, M-4 which differed from the parent strain in the production of a brown pigment and conidia, and lack of aerial mycelium. It was found to be most stable and capable of producing high antibiotic yield. The rest of the mutants, M-5 to M-14 could be grouped in the second category. The synthesis of one or more metabolites of the parent strain has been lost by mutation. Unexpectedly, a mutant, M-9 instead of synthesizing either oxytetracycline or tetracycline produced chlortetracycline. Coconut water was found inhibitory to the production of antibiotics by the parent strain and the high and low producing mutants. Modifying the medium by incorporating phosphate and adjusting the initial pH to 4.75 raised the antibiotic yield of the 10% coconut water supplemented medium of M-4 more than the control. Higher pH than the optimum shortened the lag phase but reduced the antibiotic yield while a lower initial pH prevented the growth of the organism giving negligible yield. A reduction of pH to pH 4.5 for the initial 48 hours lengthened the lag phase with almost no adverse effect on the yield. The incorporation of large amounts of coconut water aggravated the amino acid imbalance of the medium

Models of antimicrobial pressure on intestinal bacteria of the treated host populations.

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Volkova, V V; Cazer, C L; Gröhn, Y T

2017-07-01

Antimicrobial drugs are used to treat pathogenic bacterial infections in animals and humans. The by-stander enteric bacteria of the treated host's intestine can become exposed to the drug or its metabolites reaching the intestine in antimicrobially active form. We consider which processes and variables need to be accounted for to project the antimicrobial concentrations in the host's intestine. Those include: the drug's fraction (inclusive of any active metabolites) excreted in bile; the drug's fractions and intestinal segments of excretion via other mechanisms; the rates and intestinal segments of the drug's absorption and re-absorption; the rates and intestinal segments of the drug's abiotic and biotic degradation in the intestine; the digesta passage time through the intestinal segments; the rates, mechanisms, and reversibility of the drug's sorption to the digesta and enteric microbiome; and the volume of luminal contents in the intestinal segments. For certain antimicrobials, the antimicrobial activity can further depend on the aeration and chemical conditions in the intestine. Model forms that incorporate the inter-individual variation in those relevant variables can support projections of the intestinal antimicrobial concentrations in populations of treated host, such as food animals. To illustrate the proposed modeling framework, we develop two examples of treatments of bovine respiratory disease in beef steers by oral chlortetracycline and injectable third-generation cephalosporin ceftiofur. The host's diet influences the digesta passage time, volume, and digesta and microbiome composition, and may influence the antimicrobial loss due to degradation and sorption in the intestine. We consider two diet compositions in the illustrative simulations. The examples highlight the extent of current ignorance and need for empirical data on the variables influencing the selective pressures imposed by antimicrobial treatments on the host's intestinal bacteria.

Hazard prioritization and risk characterization of antibiotics in an irrigated Costa Rican region used for intensive crop, livestock and aquaculture farming.

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de la Cruz, Elba; Fournier, María Luisa; García, Fernando; Molina, Andrea; Chavarría, Guadalupe; Alfaro, Margarita; Ramírez, Fernando; Rodríguez, César

2014-01-01

Antibiotics alter the homeostasis of microbial communities and select for antibiotic-resistant bacteria in the wild. Thus, the accumulation of unnaturally high concentration of these substances in the environment due to their use in human activities can be regarded as a neglected form of pollution, especially in countries with agricultural-based economies. Qualitative and quantitative information on antibiotic usage in Costa Rica is scarce, hence the design and enforcement of prevention strategies and corrective measures is difficult. To address this issue, and aiming in the long run to contribute with a more rational use of pharmaceuticals in the tropics, we characterized the hazard associated with the antibiotics used during 2008 in agriculture, aquaculture, pig farming, veterinary medicine and human medicine in the major irrigation district of Costa Rica. Hazard indicators were calculated based on antibiotic use and a weighted algorithm that also considered antibiotic fate, toxicity, and resistance. Moreover, hazard quotients were computed using maximum environmental concentrations reported for Costa Rican surface waters and predicted no effect concentrations for aquatic organisms. The number of antibiotics used in the ATID during the study were n = 38 from 15 families. Antibiotic consumption was estimated at 1169-109908 g ha(-1) year(-1) and, distinctively, almost half of this figure was traced back to phenicols. Tetracyclines, with a particular contribution of oxytetracycline, were the most widely used antibiotics in agriculture and veterinary medicine. Oxytetracycline, florfenicol, chlortetracycline, sulfamethoxazole, erythromycin, ciprofloxacin, enrofloxacin, sulfamethazine, trimethoprim and tylosin, in that order showed the highest hazard indicators. Moreover, hazard quotients greater than 1 were calculated for oxacillin, doxycycline, oxytetracycline, sulfamethazine, and ciprofloxacin. Studies dealing with the ecotoxicology of tetracyclines, sulfonamides

Decline in extractable antibiotics in manure-based composts during composting.

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Kim, K-R; Owens, G; Ok, Y S; Park, W-K; Lee, D B; Kwon, S-I

2012-01-01

A wide variety of antibiotics have been detected in natural water samples and this is of potential concern because of the adverse environmental effects of such antibiotic residues. One of the main sources of antibiotics effluence to the surrounding environment is livestock manures which often contain elevated concentrations of veterinary antibiotics (VAs) which survive digestion in the animal stomach following application in animal husbandry practices. In Korea, livestock manures are normally used for compost production indicating that there is potential for antibiotic release to the environment through compost application to agricultural lands. Therefore, reduction of the amount of VAs in composts is crucial. The purpose of this study was to understand the influence of the composting process and the components of the compost on the levels of three common classes of antibiotics (tetracyclines, sulfonamides, and macrolides). Composted materials at different stages of composting were collected from compost manufacturing plants and the variation in antibiotic concentrations was determined. Three different antibiotics, chlortetracycline (CTC), sulfamethazine (SMZ), and tylosin (TYL) at three different concentrations (2, 10, and 20mgkg(-1)) were also applied to a mixture of pig manure and sawdust and the mixtures incubated using a laboratory scale composting apparatus to monitor the changes in antibiotic concentrations during composting together with the physicochemical properties of the composts. During composting, in both field and lab-scale investigations, the concentrations of all three different antibiotics declined below the relevant Korean guideline values (0.8mgkg(-1) for tetracyclines, 0.2mgkg(-1) for sulfonamides and 1.0mgkg(-1) for macrolides). The decline of tetracycline and sulfonamide concentrations was highly dependent on the presence of sawdust while there was no influence of sawdust on TYL decline. Copyright © 2011 Elsevier Ltd. All rights reserved.

Diurnal variations in the occurrence and the fate of hormones and antibiotics in activated sludge wastewater treatment in Oslo, Norway

International Nuclear Information System (INIS)

Plosz, Benedek Gy.; Leknes, Henriette; Liltved, Helge; Thomas, Kevin V.

2010-01-01

We present an assessment of the dynamics in the influent concentration of hormones (estrone, estriol) and antibiotics (trimethoprim, sulfamethoxazole, tetracycline, ciprofloxacin) in the liquid phase including the efficiency of biological municipal wastewater treatment. The concentration of estradiol, 17-α-ethinylestradiol, doxycycline, oxytetracycline, demeclocycline, chlortetracycline, cefuroxime, cyclophosphamide, and ifosfamide were below the limit of detection in all of the sewage samples collected within this study. Two different types of diurnal variation pattern were identified in the influent mass loads of selected antibiotics and hormones that effectively correlate with daily drug administration patterns and with the expected maximum human hormone release, respectively. The occurrence of natural hormones and antimicrobials, administered every 12 hours, shows a daily trend of decreasing contaminant mass load, having the maximum values in the morning hours. The occurrence of antibiotics, typically administered every 8 hours, indicates a daily peak value in samples collected under the highest hydraulic loading. The efficiency of biological removal of both hormones and antibiotics is shown to be limited. Compared to the values obtained in the influent samples, increased concentrations are observed in the biologically treated effluent for trimethoprim, sulfamethoxazole and ciprofloxacin, mainly as a result of deconjugation processes. Ciprofloxacin is shown as the predominant antimicrobial compound in the effluent, and it is present at quantities approximately 10 fold greater than the total mass of the other of the compounds due to poor removal efficiency and alternating solid-liquid partitioning behaviour. Our results suggest that, to increase the micro-pollutant removal and the chemical dosing efficiency in enhanced tertiary treatment, significant benefits can be derived from the optimisation of reactor design and the development of control schemes that

Prevalence of veterinary antibiotics and antibiotic-resistant Escherichia coli in the surface water of a livestock production region in northern China.

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Xuelian Zhang

Full Text Available This study investigated the occurrence of 12 veterinary antibiotics (VAs and the susceptibility of Escherichia coli (E. coli in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L(-1. The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment.

Prevalence of veterinary antibiotics and antibiotic-resistant Escherichia coli in the surface water of a livestock production region in northern China.

Science.gov (United States)

Zhang, Xuelian; Li, Yanxia; Liu, Bei; Wang, Jing; Feng, Chenghong; Gao, Min; Wang, Lina

2014-01-01

This study investigated the occurrence of 12 veterinary antibiotics (VAs) and the susceptibility of Escherichia coli (E. coli) in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L(-1). The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment.

Diurnal variations in the occurrence and the fate of hormones and antibiotics in activated sludge wastewater treatment in Oslo, Norway

Energy Technology Data Exchange (ETDEWEB)

Plosz, Benedek Gy., E-mail: benedek.plosz@niva.no [Norwegian Institute for Water Research, NIVA, Gaustadalleen 21, NO-0349, Oslo (Norway); Leknes, Henriette [Norwegian Institute for Air Research NILU, 2027 Kjeller (Norway); Liltved, Helge; Thomas, Kevin V. [Norwegian Institute for Water Research, NIVA, Gaustadalleen 21, NO-0349, Oslo (Norway)

2010-03-15

We present an assessment of the dynamics in the influent concentration of hormones (estrone, estriol) and antibiotics (trimethoprim, sulfamethoxazole, tetracycline, ciprofloxacin) in the liquid phase including the efficiency of biological municipal wastewater treatment. The concentration of estradiol, 17-{alpha}-ethinylestradiol, doxycycline, oxytetracycline, demeclocycline, chlortetracycline, cefuroxime, cyclophosphamide, and ifosfamide were below the limit of detection in all of the sewage samples collected within this study. Two different types of diurnal variation pattern were identified in the influent mass loads of selected antibiotics and hormones that effectively correlate with daily drug administration patterns and with the expected maximum human hormone release, respectively. The occurrence of natural hormones and antimicrobials, administered every 12 hours, shows a daily trend of decreasing contaminant mass load, having the maximum values in the morning hours. The occurrence of antibiotics, typically administered every 8 hours, indicates a daily peak value in samples collected under the highest hydraulic loading. The efficiency of biological removal of both hormones and antibiotics is shown to be limited. Compared to the values obtained in the influent samples, increased concentrations are observed in the biologically treated effluent for trimethoprim, sulfamethoxazole and ciprofloxacin, mainly as a result of deconjugation processes. Ciprofloxacin is shown as the predominant antimicrobial compound in the effluent, and it is present at quantities approximately 10 fold greater than the total mass of the other of the compounds due to poor removal efficiency and alternating solid-liquid partitioning behaviour. Our results suggest that, to increase the micro-pollutant removal and the chemical dosing efficiency in enhanced tertiary treatment, significant benefits can be derived from the optimisation of reactor design and the development of control schemes that

Prevalence of Veterinary Antibiotics and Antibiotic-Resistant Escherichia coli in the Surface Water of a Livestock Production Region in Northern China

Science.gov (United States)

Zhang, Xuelian; Li, Yanxia; Liu, Bei; Wang, Jing; Feng, Chenghong; Gao, Min; Wang, Lina

2014-01-01

This study investigated the occurrence of 12 veterinary antibiotics (VAs) and the susceptibility of Escherichia coli (E. coli) in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L−1. The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment. PMID:25372873

Decreased expression of LamB and Odp1 complex is crucial for antibiotic resistance in Escherichia coli.

Science.gov (United States)

Lin, Xiang-min; Yang, Man-jun; Li, Hui; Wang, Chao; Peng, Xuan-Xian

2014-02-26

We previously revealed a negative regulation of LamB in chlortetracycline-resistant Escherichia coli strain. In the present study, we first showed that the negative regulation, which was characterized by decreased abundance of LamB with elevated growth of its gene-deleted mutant in medium with antibiotics, was a general response in resistance to different classes of antibiotics using 2-DE based proteomics or/and genetically gene-deletion mutant of LamB. Then, we revealed the interaction of LamB and Odp1 which catalyzes the overall conversion of pyruvate to acetyl-CoA and CO2, and found the decrease of the complex in antibiotic-resistant strains with a minimum inhibitory concentration dose-dependent manner. Further spectrofluorometry assay indicated that LamB served as a porin to influx an antibiotic. Finally, we showed that the decreased expression of LamB and Odp1 was detected in almost of all 34 multidrug-resistant strains, which suggested that LamB and Odp1 were biomarkers for identification of antibiotic-resistant E. coli. Our results indicated that the interaction of an outer membrane protein with an energy metabolic enzyme constructed an efficient pathway to resist antibiotics. These findings provide novel insights into the mechanisms of antibiotic resistance. Our data indicate that the negative regulation by LamB is widely detected in antibiotic-resistant E. coli. LamB serves as a porin to influx an antibiotic and is interacted with Odp1. The complex decreases in antibiotic-resistant strains with a MIC dose-dependent manner. Our findings indicate that interaction of outer membrane protein with energy metabolic enzyme constructs an efficient pathway to resist antibiotics and provides novel insights into the mechanisms of antibiotic resistance. Copyright © 2014 Elsevier B.V. All rights reserved.

A Drug Combination Screen Identifies Drugs Active against Amoxicillin-Induced Round Bodies of In Vitro Borrelia burgdorferi Persisters from an FDA Drug Library.

Science.gov (United States)

Feng, Jie; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G; Zhang, Ying

2016-01-01

Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10-20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under experimental stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that appear resistant in vitro to customary first-line antibiotics for Lyme disease. To identify more effective drugs with activity against the round body form of B. burgdorferi, we established a round body persister model induced by exposure to amoxicillin (50 μg/ml) and then screened the Food and Drug Administration drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven individual drugs scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. In this amoxicillin-induced round body model, some drug candidates such as daptomycin and clofazimine also displayed enhanced activity which was similar to a previous screen against stationary phase B. burgdorferi persisters not exposure to amoxicillin. Additional candidate drugs active against round bodies identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against amoxicillin-induced round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi

Comparing the Genetic Diversity and Antimicrobial Resistance Profiles of Campylobacter jejuni Recovered from Cattle and Humans

Directory of Open Access Journals (Sweden)

Wonhee Cha

2017-05-01

Full Text Available Campylobacter jejuni, a leading cause of gastroenteritis in humans, is a foodborne pathogen that can reside in chickens, pigs, and cattle. Because resistance to fluoroquinolones and macrolides, which are commonly used to treat human infections, has emerged in C. jejuni, it is imperative to continously monitor resistance patterns and examine the genetic variation in strains from human infections and animal reservoirs. Our previous study of C. jejuni from human campylobacteriosis cases showed a significantly higher rate of tetracycline resistance compared to national trends, and identified multilocus sequence type (ST-982 and a history of cattle contact to be associated with tetracycline resistance. To further investigate these associations, we conducted a cross-sectional study to determine the frequency of antimicrobial resistance and examine the genetic diversity of C. jejuni recovered from 214 cattle at three Michigan herds. Overall, the prevalence of C. jejuni was 69.2% (range: 58.6–83.8% for the three farms, and 83.7% (n = 113 of isolates were resistant to one or more antimicrobials. Resistance to only tetracycline predominated among the cattle isolates (n = 89; 65.9% with most resistant strains belonging to ST-459 (96.5% or ST-982 (86.4%. Among the 22 STs identified, STs 459 and 982 were more prevalent in one feedlot, which reported the use of chlortetracycline in feed upon arrival of a new herd. PCR-based fingerprinting demonstrated that the ST-982 isolates from cattle and humans had identical banding patterns, suggesting the possibility of interspecies transmission. Resistance to macrolides (1.5% and ciprofloxacin (16.3% was also observed; 14 of the 22 ciprofloxacin resistant isolates represented ST-1244. Together, these findings demonstrate a high prevalence of antimicrobial resistant C. jejuni in cattle and identify associations with specific genotypes. Continuous monitoring and identification of risk factors for resistance emergence

Bandgap tailoring of in-situ nitrogen-doped TiO₂ sputtered films intended for electrophotocatalytic applications under solar light

Energy Technology Data Exchange (ETDEWEB)

Delegan, N.; El Khakani, M. A., E-mail: elkhakani@emt.inrs.ca [Institut National de la Recherche Scientifique, Centre Énergie, Matériaux et Télécommunications, 1650, Boulevard Lionel-Boulet, Varennes, Québec J3X-1S2 (Canada); Daghrir, R.; Drogui, P. [Institut National de la Recherche Scientifique, Centre Eau, Terre et Environnement, 490 Rue de la Couronne, Québec G1K-9A9 (Canada)

2014-10-21

We report on a reactive RF-sputtering process permitting the in-situ nitrogen doping of TiO₂ films in order to shift their photoactivity from UV to visible range. By carefully controlling the relative nitrogen-to-argon mass flow rate ratio (within the 0%–25% range) in the sputter deposition chamber, TiO₂:N films were grown with nitrogen contents ranging from 0 to 6.2 at. %, as determined by high-resolution X-ray spectroscopy measurements. A systematic investigation of the crystalline structure of the TiO₂:N films, as a function of their N content, revealed that low N contents (0.2–0.3 at. %) induce crystallization in the rutile phase while higher N contents (≥1.4 at. %) were accompanied with the recovery of the anatase structure with an average crystallite size of ~35 nm. By using both UV-Vis absorption and spectroscopic ellipsometry measurements, we were able to quantitatively determine the bandgap (E{sub g}) variation of the TiO₂:N films as a function of their N content. Thus, we have demonstrated that the E{sub g} of the TiO₂:N films effectively narrows from 3.2 eV down to a value as low as ~2.3 eV for the optimal N doping concentration of 3.4 at. % (higher N incorporation does not translate into further red shifting of the TiO₂:N films' E{sub g}). The photoactivity of the TiO₂:N films under visible light was confirmed through electro-photocatalytic decomposition of chlortetracycline (CTC, an emerging water pollutant) under standard 1.5AM solar radiation. Thus, CTC degradation efficiencies of up to 98% were achieved with 2 hours process cycles under simulated solar light. Moreover, the electro-photocatalytic performance of the TiO₂:N films is shown to be directly correlated to their optoelectronic properties (namely their bandgap narrowing).

Direct screening of tetracyclines in water and bovine milk using room temperature phosphorescence detection

International Nuclear Information System (INIS)

Traviesa-Alvarez, J.M.; Costa-Fernandez, J.M.; Pereiro, R.; Sanz-Medel, A.

2007-01-01

A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin with 1 M HCl (for milk samples a second regeneration step, using methanol, should be performed). A sample throughput of about 20 samples per hour was obtained. Optimum experimental conditions include a pH 9, a Eu(III) concentration of 2 x 10 -4 M and 8 mM sodium sulphite as chemical deoxygenant. The phosphorescence emitted by the europium-TCC complexes was measured at 394 and 617 nm for excitation and emission wavelengths, respectively. The unreliability region, given by the probability of false positives and false negatives, respectively (set at 5% in both cases) was in the range between 0.2 and 11.6 nM for detection of tetracyclines in water samples (at a cut-off level of 4 nM) and in the range between 165 and 238 nM for detection of tetracyclines in milk (cut-off level fixed at the normative EU level of 200 nM). Finally, the applicability of the proposed screening optosensor was tested for the reliable control of tetracyclines in contaminated and uncontaminated water and milk samples

Spread of tetracycline resistance genes at a conventional dairy farm

Directory of Open Access Journals (Sweden)

Martina eKyselkova

2015-05-01

Full Text Available The use of antibiotics in animal husbandry contributes to the worldwide problem of increasing antibiotic resistance in animal and human pathogens. Intensive animal production is considered an important source of antibiotic resistance genes released to the environment, while the contribution of smaller farms remains to be evaluated. Here we monitor the spread of tetracycline resistance (TC-r genes at a middle-size conventional dairy farm, where chlortetracycline (CTC, as intrauterine suppository is prophylactically used after each calving. Our study has shown that animals at the farm acquired the TC-r genes in their early age (1-2 weeks, likely due to colonization with TC-resistant bacteria from their mothers and/or the farm environment. The relative abundance of the TC-r genes tet(W, tet(Q and tet(M in fresh excrements of calves was about 1-2 orders of magnitude higher compared to heifers and dairy cows, possibly due to the presence of antibiotic residues in milk fed to calves. The occurrence and abundance of TC-r genes in fresh excrements of heifers and adult cows remained unaffected by intrauterine CTC applications, with tet(O, tet(Q and tet(W representing a ‘core TC-resistome’ of the farm, and tet(A, tet(M, tet(Y and tet(X occurring occasionally. The genes tet(A, tet(M, tet(Y and tet(X were shown to be respectively harbored by Shigella, Lactobacillus and Clostridium, Acinetobacter, and Wautersiella. Soil in the farm proximity, as well as field soil to which manure from the farm was applied, was contaminated with TC-r genes occurring in the farm, and some of the TC-r genes persisted in the field over 3 months following the manure application. Concluding, our study shows that antibiotic resistance genes may be a stable part of the intestinal metagenome of cattle even if antibiotics are not used for growth stimulation, and that smaller dairy farms may also contribute to environmental pollution with antibiotic resistance genes.

Protein phosphatases decrease their activity during capacitation: a new requirement for this event.

Directory of Open Access Journals (Sweden)

Janetti R Signorelli

Full Text Available There are few reports on the role of protein phosphatases during capacitation. Here, we report on the role of PP2B, PP1, and PP2A during human sperm capacitation. Motile sperm were resuspended in non-capacitating medium (NCM, Tyrode's medium, albumin- and bicarbonate-free or in reconstituted medium (RCM, NCM plus 2.6% albumin/25 mM bicarbonate. The presence of the phosphatases was evaluated by western blotting and the subcellular localization by indirect immunofluorescence. The function of these phosphatases was analyzed by incubating the sperm with specific inhibitors: okadaic acid, I2, endothall, and deltamethrin. Different aliquots were incubated in the following media: 1 NCM; 2 NCM plus inhibitors; 3 RCM; and 4 RCM plus inhibitors. The percent capacitated sperm and phosphatase activities were evaluated using the chlortetracycline assay and a phosphatase assay kit, respectively. The results confirm the presence of PP2B and PP1 in human sperm. We also report the presence of PP2A, specifically, the catalytic subunit and the regulatory subunits PR65 and B. PP2B and PP2A were present in the tail, neck, and postacrosomal region, and PP1 was present in the postacrosomal region, neck, middle, and principal piece of human sperm. Treatment with phosphatase inhibitors rapidly (≤1 min increased the percent of sperm depicting the pattern B, reaching a maximum of ∼40% that was maintained throughout incubation; after 3 h, the percent of capacitated sperm was similar to that of the control. The enzymatic activity of the phosphatases decreased during capacitation without changes in their expression. The pattern of phosphorylation on threonine residues showed a sharp increase upon treatment with the inhibitors. In conclusion, human sperm express PP1, PP2B, and PP2A, and the activity of these phosphatases decreases during capacitation. This decline in phosphatase activities and the subsequent increase in threonine phosphorylation may be an important

Direct screening of tetracyclines in water and bovine milk using room temperature phosphorescence detection

Energy Technology Data Exchange (ETDEWEB)

Traviesa-Alvarez, J M [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/Julian Claveria 8, 33006 Oviedo (Spain); Costa-Fernandez, J M [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/Julian Claveria 8, 33006 Oviedo (Spain); Pereiro, R [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/Julian Claveria 8, 33006 Oviedo (Spain); Sanz-Medel, A [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/Julian Claveria 8, 33006 Oviedo (Spain)

2007-04-18

A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin with 1 M HCl (for milk samples a second regeneration step, using methanol, should be performed). A sample throughput of about 20 samples per hour was obtained. Optimum experimental conditions include a pH 9, a Eu(III) concentration of 2 x 10{sup -4} M and 8 mM sodium sulphite as chemical deoxygenant. The phosphorescence emitted by the europium-TCC complexes was measured at 394 and 617 nm for excitation and emission wavelengths, respectively. The unreliability region, given by the probability of false positives and false negatives, respectively (set at 5% in both cases) was in the range between 0.2 and 11.6 nM for detection of tetracyclines in water samples (at a cut-off level of 4 nM) and in the range between 165 and 238 nM for detection of tetracyclines in milk (cut-off level fixed at the normative EU level of 200 nM). Finally, the applicability of the proposed screening optosensor was tested for the reliable control of tetracyclines in contaminated and uncontaminated water and milk samples.

Cholesterol addition aids the cryopreservation of dromedary camel (Camelus dromedarius) spermatozoa.

Science.gov (United States)

Crichton, Elizabeth G; Pukazhenthi, Budhan S; Billah, M; Skidmore, Julian A

2015-01-15

The cryopreservation of dromedary camel (Camelus dromedarius) sperm has proved challenging with little success reported. The routine application of artificial insemination with frozen semen would assist the flow of valuable genetic material nationally and internationally. The current study sought to examine the effects of cholesterol (cholesterol-loaded cyclodextrin [CLC]) preloading on camel sperm cryosurvival. Ejaculates (n = 3 males; 3 ejaculates per male) were collected using an artificial vagina during the breeding season and extended in HEPES-buffered Tyrode's albumin lactate pyruvate (TALP) and allowed to liquefy in the presence of papain (0.1 mg/mL) before removal of the seminal plasma by centrifugation. Sperm pellets were resuspended (120 million/mL) in fresh TALP and incubated (15 minutes; 37 °C) with 0, 1.5, or 4.5 mg CLC/mL. Sperm suspensions were then centrifuged and reconstituted in INRA-96 containing 20% (v:v) egg yolk and 2.5% (v:v) methylformamide, loaded in 0.5-mL plastic straws, sealed, and cooled for 20 minutes at 4 °C. Straws were frozen over liquid nitrogen (4 cm above liquid; 15 minutes), plunged, and stored. Sperm motility, forward progressive status, and acrosomal integrity were recorded at 0 and 3 hours after thawing and compared with these same parameters before freezing. Aliquots also were stained with chlortetracycline hydrochloride to assess spontaneous sperm capacitation status before freezing and post-thaw. Pretreatment with CLC (1.5 and 4.5 mg/mL) enhanced cryosurvival. Post-thaw sperm motility was highest (P < 0.05) in 1.5 mg CLC/mL immediately after thawing (44%) and after 3 hours incubation at room temperature (34%). Highest post-thaw sperm progressive status was also achieved in the presence of 1.5 CLC. Greater proportions of spermatozoa retained acrosomal membrane integrity when cryopreserved in the presence of CLC, but there was no difference between 1.5 and 4.5 CLC. Although thawed spermatozoa underwent spontaneous

Tetracycline residues and tetracycline resistance genes in groundwater impacted by swine production facilities

Science.gov (United States)

Mackie, R.I.; Koike, S.; Krapac, I.; Chee-Sanford, J.; Maxwell, Susan; Aminov, R.I.

2006-01-01

Antibiotics are used at therapeutic levels to treat disease; at slightly lower levels as prophylactics; and at low, subtherapeutic levels for growth promotion and improvement of feed efficiency. Over 88% of swine producers in the United States gave antimicrobials to grower/finisher pigs in feed as a growth promoter in 2000. It is estimated that ca. 75% of antibiotics are not absorbed by animals and are excreted in urine and feces. The extensive use of antibiotics in swine production has resulted in antibiotic resistance in many intestinal bacteria, which are also excreted in swine feces, resulting in dissemination of resistance genes into the environment.To assess the impact of manure management on groundwater quality, groundwater samples have been collected near two swine confinement facilities that use lagoons for manure storage and treatment. Several key contaminant indicators-including inorganic ions, antibiotics, and antibiotic resistance genes-were analyzed in groundwater collected from the monitoring wells. Chloride, ammonium, potassium, and sodium were predominant inorganic constituents in the manure samples and served as indicators of groundwater contamination. Based on these analyses, shallow groundwater has been impacted by lagoon seepage at both sites. Liquid chromatography-mass spectroscopy (LC-MS) was used to measure the dissolved concentrations of tetracycline, chlortetracycline, and oxytetracycline in groundwater and manure. Although tetracyclines were regularly used at both facilities, they were infrequently detected in manure samples and then at relatively trace concentrations. Concentrations of all tetracyclines and their breakdown products in the groundwater sampled were generally less than 0.5 ??g/L.Bacterial tetracycline resistance genes served as distinct genotypic markers to indicate the dissemination and mobility of antibiotic resistance genes that originated from the lagoons. Applying PCR to genomic DNA extracted from the lagoon and

Evolution of microbial communities during electrokinetic treatment of antibiotic-polluted soil.

Science.gov (United States)

Li, Hongna; Li, Binxu; Zhang, Zhiguo; Zhu, Changxiong; Tian, Yunlong; Ye, Jing

2018-02-01

The evolution of microbial communities during the electrokinetic treatment of antibiotic-polluted soil (EKA) was investigated with chlortetracycline (CTC), oxytetracycline (OTC) and tetracycline (TC) as template antibiotics. The total population of soil microorganisms was less affected during the electrokinetic process, while living anti-CTC, anti-OTC, anti-TC and anti-MIX bacteria were inactivated by 10.48%, 31.37%, 34.76%, and 22.08%, respectively, during the 7-day treatment compared with antibiotic-polluted soil without an electric field (NOE). Accordingly, samples with NOE treatment showed a higher Shannon index than those with EKA treatment, indicating a reduction of the microbial community diversity after electrokinetic processes. The major taxonomic phyla found in the samples of EKA and NOE treatment were Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. And the distribution of Actinobacteria, Cyanobacteria, and Chloroflexi was greatly decreased compared with blank soil. In the phylum Proteobacteria, the abundance of Alphaproteobacteria was greatly reduced in the soils supplemented with antibiotics (from 13.40% in blank soil to 6.43-10.16% after treatment); while Betaproteobacteria and Deltaproteobacteria showed a different trend with their abundance increased compared to blank soil, and Gammaproteobacteria remained unchanged for all treatments (2.36-2.78%). The varied trends for different classes indicated that the major bacterial groups changed with the treatments due to their different adaptability to the antibiotics as well as to the electric field. SulI being an exception, the reduction ratio of the observed antibiotic resistance genes (ARGs) including tetC, tetG, tetW, tetM, intI1, and sulII in the 0-2cm soil sampled with EKA versus NOE treatment reached 55.17%, 3.59%, 99.26%, 89.51%, 30.40%, and 27.92%, respectively. Finally, correlation analysis was conducted between antibiotic-resistant bacteria, ARGs and taxonomic bacterial classes. It

NOVEL ANTIBIOTIC RESISTANCE DETERMINANTS FROM AGRICULTURAL SOIL EXPOSED TO ANTIBIOTICS WIDELY USED IN HUMAN MEDICINE AND ANIMAL FARMING.

Science.gov (United States)

Lau, Calvin Ho-Fung; van Engelen, Kalene; Gordon, Stephen; Renaud, Justin; Topp, Edward

2017-06-16

Antibiotic resistance has emerged globally as one of the biggest threats to human and animal health. Although the excessive use of antibiotics is recognized for accelerating the selection for resistance, there is a growing body of evidence suggesting that natural environments are "hotspots" for the development of both ancient and contemporary resistance mechanisms. Given that pharmaceuticals can be entrained onto agricultural land through anthropogenic activities, this could be a potential driver for the emergence and dissemination of resistance in soil bacteria. Using functional metagenomics, we interrogated the "resistome" of bacterial communities found in a collection of Canadian agricultural soil, some of which had been receiving antibiotics widely used in human medicine (macrolides) or food animal production (sulfamethazine, chlortetracycline and tylosin) for up to 16 years. Of the 34 new antibiotic resistance genes (ARGs) recovered, the majority were predicted to encode for (multi)drug efflux systems, while a few share little to no homology with established resistance determinants. We characterized several novel gene products, including putative enzymes that can confer high-level resistance against aminoglycosides, sulfonamides, and broad range of beta-lactams, with respect to their resistance mechanisms and clinical significance. By coupling high-resolution proteomics analysis with functional metagenomics, we discovered an unusual peptide, PPP AZI 4 , encoded within an alternative open-reading frame not predicted by bioinformatics tools. Expression of the proline-rich PPP AZI 4 can promote resistance against different macrolides but not other ribosomal-targeting antibiotics, implicating a new macrolide-specific resistance mechanism that could be fundamentally linked to the evolutionary design of this peptide. IMPORTANCE Antibiotic resistance is a clinical phenomenon with an evolutionary link to the microbial pangenome. Genes and protogenes encoding for

Antibiotic susceptibility profiles of Mycoplasma synoviae strains originating from Central and Eastern Europe.

Science.gov (United States)

Kreizinger, Zsuzsa; Grózner, Dénes; Sulyok, Kinga M; Nilsson, Kristin; Hrivnák, Veronika; Benčina, Dušan; Gyuranecz, Miklós

2017-11-17

Mycoplasma synoviae causes infectious synovitis and respiratory diseases in chickens and turkeys and may lead to egg shell apex abnormalities in chickens; hence possesses high economic impact on the poultry industry. Control of the disease consists of eradication, vaccination or medication. The aim of the present study was to determine the in vitro susceptibility to 14 different antibiotics and an antibiotic combination of M. synoviae strains originating from Hungary and other countries of Central and Eastern Europe. Minimal inhibitory concentration (MIC) values of a total of 41 M. synoviae strains were determined by the microbroth dilution method. The strains were collected between 2002 and 2016 and originated from Hungary (n = 26), Austria (n = 3), the Czech Republic (n = 3), Slovenia (n = 3), Ukraine (n = 3), Russia (n = 2) and Serbia (n = 1). Tetracyclines (with MIC 50 values of 0.078 μg/ml, ≤0.25 μg/ml and 0.5 μg/ml for doxycycline, oxytetracycline and chlortetracycline, respectively), macrolides (with MIC 50 values of ≤0.25 μg/ml for tylvalosin, tylosin and tilmicosin), pleuromutilins (with MIC 50 values of 0.078 μg/ml and ≤0.039 μg/ml for tiamulin and valnemulin) and the combination of lincomycin and spectinomycin (MIC 50 1 μg/ml (0.333/0.667 μg/ml)) were found to be the most effective antibiotic agents against M. synoviae in vitro. High MIC values were detected in numerous strains for fluoroquinolones (with MIC 50 values of 1.25 μg/ml and 2.5 μg/ml for enrofloxacin and difloxacin), neomycin (MIC 50 32 μg/ml), spectinomycin (MIC 50 2 μg/ml), lincomycin (MIC 50 0.5 μg/ml) and florfenicol (MIC 50 4 μg/ml). Nevertheless, strains with elevated MIC values were detected for most of the applied antibiotics. In the medical control of M. synoviae infections the preliminary in vitro antibiotic susceptibility testing and the careful evaluation of the data are crucial. Based on the in vitro examinations

Evaluation of the Charm maximum residue limit β-lactam and tetracycline test for the detection of antibiotics in ewe and goat milk.

Science.gov (United States)

Beltrán, M C; Romero, T; Althaus, R L; Molina, M P

2013-05-01

CCβ for tetracyclines was also lower than EU-MRL for chlortetracycline (ewe milk: ≤ 50 µg/kg; goat milk: 75 µg/kg), oxytetracycline (≤ 50 µg/kg), and tetracycline (≤ 50 µg/kg). Regarding the 4-epimers of these tetracyclines only 4-epioxytetracycline was detected by the Charm MRL BLTET test below EU-MRL (ewe milk: 75 µg/kg; goat milk: ≤ 50 µg/kg). Acidiol had no effect on the performance of the test. The Charm MRL BLTET test could be used routinely with adapted test procedure for the fast screening of ewe and goat milk. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antimicrobial drug use and risk factors associated with treatment incidence and mortality in Swiss veal calves reared under improved welfare conditions.

Science.gov (United States)

Lava, M; Schüpbach-Regula, G; Steiner, A; Meylan, M

2016-04-01

Ninety-one Swiss veal farms producing under a label with improved welfare standards were visited between August and December 2014 to investigate risk factors related to antimicrobial drug use and mortality. All herds consisted of own and purchased calves, with a median of 77.4% of purchased calves. The calves' mean age was 29±15days at purchasing and the fattening period lasted at average 120±28 days. The mean carcass weight was 125±12kg. A mean of 58±33 calves were fattened per farm and year, and purchased calves were bought from a mean of 20±17 farms of origin. Antimicrobial drug treatment incidence was calculated with the defined daily dose methodology. The mean treatment incidence (TIADD) was 21±15 daily doses per calf and year. The mean mortality risk was 4.1%, calves died at a mean age of 94±50 days, and the main causes of death were bovine respiratory disease (BRD, 50%) and gastro-intestinal disease (33%). Two multivariable models were constructed, for antimicrobial drug treatment incidence (53 farms) and mortality (91 farms). No quarantine, shared air space for several groups of calves, and no clinical examination upon arrival at the farm were associated with increased antimicrobial treatment incidence. Maximum group size and weight differences >100kg within a group were associated with increased mortality risk, while vaccination and beef breed were associated with decreased mortality risk. The majority of antimicrobial treatments (84.6%) were given as group treatments with oral powder fed through an automatic milk feeding system. Combination products containing chlortetracycline with tylosin and sulfadimidine or with spiramycin were used for 54.9%, and amoxicillin for 43.7% of the oral group treatments. The main indication for individual treatment was BRD (73%). The mean age at the time of treatment was 51 days, corresponding to an estimated weight of 80-100kg. Individual treatments were mainly applied through injections (88.5%), and included

Compost and residues from biogas plant as potting substrates for salt-tolerant and salt-sensitive plants

Energy Technology Data Exchange (ETDEWEB)

Cam Van, Do Thi

2013-08-01

proportions of compost and additives (Styromull or Perlite). The results show that the large percentage (> 50% by volume) of compost in the substrate had negative effects on plant growth and nutrient uptake (N, P, K, Mg and Na) because of its high salt content in compost-based substrates. However, both yield formation and nutrient uptake of the studied plants when grown in peat-based substrates significantly increased comparing to those of compost-based substrates and almost gained the level of the control. Especially, the growth of Salvia was significantly improved. Consequently, compost-based media (with more than 50% of compost) may not be recommended for salt sensitive ornamental plants, while less than 25% volume of compost incorporated with Peat creates favorable peat-based substrates which reasonably enhanced growth of Pelargonium and Salvia. Investigating antibiotic uptake by cabbage (Brassica oleracea var. capitata f. abba) from the manure-amended soils containing high and low carbon content spiked with the two antibiotics Chlortetracycline and Sulfamethazine was targeted as the third objective. The input concentrations of the studied antibiotics were 100, 200 and 400 {mu}g/kg regarded to their present concentration range in Chinese top soils. The antibiotics in plant materials were analyzed by HPLC-MS after extraction. The results reveal that the presence of available high carbon content in the soil increased crop yield of cabbage. However antibiotics were not detected in the cabbage materials according to the antibiotic employment with the initial studied concentrations. It may be concluded that with the small amounts of antibiotics applied to the soils, there is no risk of uptake of antibiotics by plants.

Reduction of toxic effects of aflatoxin B1 by using baker yeast (Saccharomyces cerevisiae in growing broiler chicks diets Redução dos efeitos tóxicos da aflatoxina B1, utilizando-se levedura de panificação (Saccharomyces cerevisiae, na dieta de pintos de corte em crescimento

Directory of Open Access Journals (Sweden)

Kemal Çelýk

2003-06-01

Full Text Available This study was carried out to investigate the effects of adding baker yeast (BY, chlortetracycline (CTC and both BY + CTC to a control diet containing 200 ng/g of aflatoxin B1 (C + AFB1 on performance, serum parameters and pathologyc alterations of broilers. A total 100 chicks (Ross PM 3 were divided into five groups in individual cages and each containing 20 animals. BY, a rich source of protein and vitamin B complex, was mixed into the diets at 2.0 %, CTC was mixed into the diet at 2.5 ng/g. Feed consumption, body weight and feed efficiency were recorded weekly. Serum parameters and pathologyc alterations were determined at the end of the study. Dead animals were recorded daily. Liver changes were clearly apparent in the C+AFB1and C+ AFB1+CTC most of the livers were enlarged, yellow and had pethecial hemorrhages. Canalicula cholestosis was absent in group C+AFB1 and C+ AFB1+CTC, but not others. When compared to the control (C group, alkaline phosphatase (ALP, appear to be significantly increased in the C+AFB1 and C+CTC+ AFB1 groups. Serum glutamic oxalacetic transaminase (GOTwas increased in C+AFB1 birds. Serum alphaphetoprotein was not affected by the treatments. Feed consumption and body weight were significantly reduced in group AFB1. Birds receiving BY + AFB1, CTC + AFB1 and BY + CTC + AFB1 had a significantly higher body weight than group C+AFB1. Feed efficiency was better in group CTC + AFB1 than the others. The findings of this research suggest tha BY (2% can partly counteract some of the toxic effects of AFB1.Este estudo foi desenvolvido para avaliar os efeitos da adição de Levedura de panificação (BY e cortetraciclina (CTC e ambos BY+CTC a uma dieta controle © contendo 200 ng/g de aflatoxina B1 (C+AFB1 sobre desempenho, parâmetros séricos e alterações patológicas de frangos de corte. Um total de 100 pintinhos (Ross PM3 foi dividido em cinco grupos, em gaiolas individuais, contendo 20 animais para cada grupo. A levedura de