An automated HPLC determination of meticlorpindol in eggs with UV absorbance detection, using on-line dialysis and pre-concentration as sample clean-up; occurrence in and carry over to eggs.

A fully automated HPLC determination of the coccidiostat meticlorpindol in whole egg, egg white and yolk is described. The sample homogenate is dialysed on-line against water. The dialysate is concentrated on-line on a short reversed-phase (RP) column.

[Amprolium residues in eggs following administration of amprolium/ethopabate in laying hens and breeding hens].

Amprolium may be used as a coccidiostat in rearing hens and is a therapeutical agent used in laying hens. As a result of cross contamination, low amprolium levels may occur in feed. Feed containing a concentration of amprolium ranging from 5 to 250 mg/kg was therefore supplied to groups of laying hens.

[The occurrence of sulfa residues in unpasteurized farm milk].

The results of studies in 1984 and 1985 on the incidence of residues of sulphonamides in raw tank milk showed that, from 2 to 11 per cent milk was contaminated with Dapsone in the Netherlands. In 1984 sulphadimidine was found to be present in approximately six per cent of the samples of tank milk. In 1985, residues of Dapsone were detected, in approximately six per cent of the milk destined for consumption.

[The occurrence of dapsone residues following a one-time oral, intramuscular and intramammary application in healthy dairy cows].

Dapsone is frequently used as a bacteriostatic drug in the treatment of mastitis, endometritis and footrot (necrotic pododermatitis). The farmer usually obtains this drug by 'non-ethical' channels. A regular scheme of checking the milk for residues of sulphonamides will be introduced in 1986.

[Automated determination of 4,4'-diaminodiphenylsulfone (DDS) and acetyl metabolites (MADDS and DADDS) in milk with the FAST-LC system].

With the described method it is possible to determinate residues of Dapsone (DDS) and its acetylated metabolites (mono- and diacetyldapsone) in milk. The determination is being carried out with a FAST-LC system (Fully Automated Sample Treatment Liquid Chromatography). The purification is a combination of dialysing the milk against water and absorption of the nonpolar components from the dialysate on the preconcentration column of the LC-system used (RP, 40 microns).