"Mice

Adult virgin female CD-1 mice (61-71 d old), used in the MTD determination, and timed-pregnant mice of the same age and strain, used in the reproductive study, were purchased from the Charles River Breeding Laboratories (Wilmington, Mass.). Day 1 of pregnancy was considered to be the day a sperm plug was found.

Facilities

The mice were maintained at the Brigham Young University animal laboratory facilities for the duration of the study. They were housed in solid-bottomed cages with corn-cob bedding and were fed Wayne Lab Blox and tap water ad libitum. Room temperature was kept at 22-24°C, and a 12-h light period began at 6 a.m. each day."

"There were 50 pregnant mice randomly assigned to each treatment group, which received a dose of a particular chemical based on the results of the prior MTD study (150 treated mice plus 50 shared vehicle controls for a total of 200 mice per block). The mice were individually housed in separate cages and assigned shelf locations according to a randomized block design."

"Mice failing to deliver by d 23 were killed by cervical dislocation, and their uteri were immersed in a 1% solution of sodium sulfide to determine if implantation had occurred."

P0 Female CD-1 Mice