Publications by authors named "H Keukens"

A reversed-phase liquid chromatography method for nicarbazin in broiler feeds and premixtures was developed, validated, and interlaboratory studied. The extraction solvent was an acetonitrile-methanol (1 + 1) mixture. For feedingstuffs, water was also added.

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The fate of ivermectin (IVM) residues was studied throughout the processing of daily bulk milk from 30 ewes (taken up to 33 d following subcutaneous administration of 0.2 mg IVM/kg b.w.

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Ivermectin (IVM) concentrations in plasma and milk were studied in six Istrian Pramenka dairy sheep after a single subcutaneous dose of 0.2 mg/kg b.w.

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A method for the detection of virginiamycin M1 as a marker compound of virginiamycin at sub-additive level in pig, calf, piglet, sow, poultry, cattle and laying hen feeds was developed and validated. Both UV detection at 230 nm and MS detection were applied. Virginiamycin M1 was extracted from animal feeds with ethyl acetate after wetting of the feed with water followed by clean-up on Sep-Pak silica gel and OASIS HLB cartridges.

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Colistin (polymyxin E) is a cyclic polypeptide with a potent bactericidal action against most gramnegative bacilli. When used parenterally, polymyxins should be given with great care as they have a very small safety range, and easily induce neurotoxicity and nephrotoxicity. A dose of 39.

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