Publications by authors named "J Meirlaen"

Antibiotic resistant bacteria and antibiotic residues can enter the environment when using animal manure as fertilizer. Twenty-five mixed beef cattle farmyard manure samples and 9 mixed fattening calf slurry samples from different farms across Belgium were investigated for the presence of 69 antibiotic residues, antibiotic resistant and spp. Doxycycline, oxytetracycline, ciprofloxacin, enrofloxacin, flumequine and lincomycin were detected in all fattening calf slurry samples with mean concentrations of 2776, 4078, 48, 31, 536 and 36 µg/kg manure, respectively.

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Pig manure may contain antibiotic residues, antibiotic-resistant bacteria or pathogens, which may reach the environment upon fertilization. During this study, 69 antibiotic residues belonging to 12 classes were quantified in 89 pig slurry samples. These samples were also studied for the presence of and for resistant to meropenem, colistin, ciprofloxacin, or cefotaxim.

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Veterinary antimicrobials can spread via manure onto agricultural fields, representing an emission of these products or their active metabolites into the environment. This causes concerns regarding the role of antimicrobial residues in the development, selection and spread of resistance. Aiming to approach this issue quantitatively, first a literature review was performed on the bioavailability and extent of in vivo biotransformation of twelve antimicrobials commonly used in pigs orally, and on the level of their persistence in manure.

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During the summer of 1999, two automated water quality measurement stations were installed along the Dender river in Belgium. The variables dissolved oxygen, temperature, conductivity, pH, rain-intensity, flow and solar radiation were measured continuously. In this paper these on-line measurement series are presented and interpreted using also additional measurements and ecological expert-knowledge.

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Uncertainty is a central concept in the decision-making process, especially when dealing with biological systems subject to large natural variations. In the design of activated sludge systems, a conventional approach in dealing with uncertainty is implicitly translating it into above-normal safety factors, which in some cases may even increase the capital investments by an order of magnitude. To obviate this problem, an alternative design approach explicitly incorporating uncertainty is herein proposed.

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