Ddt residues on pasture and in the butter-fat of cows grazing pasture treated with ddt prills and ddt/superphosphate

Abstract

DDT was determined in the butterfat of cows grazed on pasture at various intervals after it had been top-dressed with either DDT priUs or DDT/superphosphate dust, each at a nominal rate of 2 lb pp'-DDT/ ac.Approximately five times less DDT was found in the butterfat of cows grazed on the prill-treated areas, and this corresponded to the lower degree of pasture contamination from the use of DDT prills.Data are presented on the correlation between DDT residues on pasture and in butterfat, the influence of formulation of DDT on the length of withholding periods for lactating cows and on the rate of decontamination of dairy cows, having DDT in the body fat, when removed to DDT-free pasture.

Residue Reviews

“…on trash after 96 days. In New Zealand, HARRISON et al (1965) examined DDT residues in butterfat of cows grazing on pasture treated with DDT prills (pellets) and DDT superphosphate fertilizer, finding five times less contamination after pellet use. Residues of DDT in sheep omental fat and cow's milk were simUar whether the animals grazed areas treated evenly or unevenly with pellets, indicating that grazing was unselective (HARRISON and SHANKS 1967).…”