ABSTRACT
The herbicide oxadiazon, 2-(tert-butyl)-4-(2,4-dichloro-5-isopropyloxy-phenyl)-delta 2-1,3,4-oxadiazoline 5-one, was fed in a total diet at three dosage levels to groups of dairy cows (0.5, 2.5, and 25 ppm) and to groups of male and laying female quail (20, 80, and 160 ppm) for 28 days. Control animals received basal diet rations. No residue (less than 5 ppb) was detected in milk or cream after three days withdrawal from fortified feed. The maximum plateau reached in milk was 83.8 ppb at the highest dosage fed. Tissues of cows sacrificed on the 12th day of withdrawal showed no residue (less than 20 ppb). Birds were sacrified at weekly intervals during acclimation, intake, and withdrawal periods. Eggs were collected at the same intervals. Tissues were free of oxadiazon residue (less than 40 ppb) within two to seven days of returning the quail to the basal ration, and the eggs were residue-free within seven to fourteen days. The maximum residue found in adipose tissue of quail and their fresh eggs was 3100 ppb and 5400 ppb, respectively at the greatly exaggerated dosage of 160 ppm in the diet. A comprehensive analytical methodology, including liquid-liquid partition, absorption chromatography and electron-capture gas chromatography will be discussed.
Subject(s)
Herbicides/metabolism , Oxadiazoles/metabolism , Pesticide Residues/metabolism , Quail/metabolism , Adipose Tissue/metabolism , Animals , Cattle , Eggs/analysis , Female , Herbicides/analysis , Male , Milk/analysis , Oxadiazoles/analysis , Pesticide Residues/analysis , Time FactorsABSTRACT
The development of a reagent-impregnated paper strip test for niacin is described. The test system is based on the formation of cyanogen chloride by the reaction of chloramine-T and potassium thiocyanate in the presence of citric acid. Rupture of the pyridine ring of niacin by cyanogen chloride yields gamma-carboxy glutaconic aldehyde and coupling with a primary aromatic amine produces a yellow color. Sensitivity to niacin, both in known solutions and from extracts of 378 clinical mycobacteria isolates, equalled or exceeded that of other methods for detection of niacin. Correlation with other tests for mycobacterial niacin was excellent.
