||Research Triangle Inst., Research Triangle Park, NC. Center for Life Sciences and Toxicology.; Goodyear Tire and Rubber Co., Akron, OH.; Environmental Protection Agency, Washington, DC. Office of Toxic Substances.
Male and female CD (Sprague-Dawley) weaning rats (the FO generation) were administered Wingstay 100 (CAS No. 68953-84-4) in 2% corn oil in the feed at 0, 120, 400, and 1500 ppm, available ad libitum, 30 animals/sex/dose, for ten weeks. Body weights and feed consumption were recorded weekly, and clinical signs were recorded at least once daily. Vaginal cytology was evaluated for the last three weeks of the prebreed period. Animals were then randomly mated within treatment groups for a two-week mating period to produce the Fi generation, with exposure continued. FO males were necropsied after the delivery period, with histologic evaluation of reproductive and target tissues for high dose and control males. Fi litters were culled to ten pups on postnatal day (pnd) 4 and weaned on pnd 21. At weaning, three weanlings/sex/Iitter were necropsied, and 30/sex/dose were selected as F1 parents of the F2 generation. AII nonselected F1 weanlings were euthanized and discarded with the concurrence of the Sponsor. FO females were then necropsied with histopathology of reproductive and target organs for high dose and control animals. Selected Fi weanlings, 30/sex/dose, were administered Wingstay 100 in the diet for a ten-week prebreed exposure period (with acquisition of vaginal patency in females and preputial separation in males assessed and vaginal cytology evaluated during the last three weeks). They were then mated for a two-week mating period as described above. At weaning of F2 litters, three weanlings/sex/ litter were necropsied; all nonselected F2 weanlings were euthanized and discarded with concurrence of the Sponsor. F1 males were necropsied after the delivery period, with histopathology as described above. After weaning of the F2 litters, parental F1 females were then necropsied with histopathology as described above.