"Body weights and clinical signs were recorded on the day after arrival and before mating; observations for morbidity and mortality were made daily. Females selected for the study were weighed on Days 1, 7-17 and 22G. Feed was weighed on Days 1, 3, 5, 7, 9, 11, 13, 15, 17, 19 and 22G and individual clinical signs were recorded each morning on Days 1-22G (prior to exposure on Days 7-16G) and in the afternoon on Days 7-16G (after animals were returned to home cages). Group observations, including the animals' responsiveness to an administered sound stimulus i.e., tapping the side of the exposure chamber with a piece of metal, were recorded hourly during exposure and approximately 15 minutes post-exposure. Due to the design of the exposure chambers, group observations were limited to those animas which could be seen in the front half of the chamber."

"Females vere sacrificed by the inhalation of carbon dioxide on Day 22 of gestation and were examined for gross pathologic changes. The uterus was removed and opened and the types of nidations (live or dead fetuses, early or late resorptions) and their relative positions were recorded. The uterus of each apparently "non-pregnant" rat was opened and stained with ammonium sulfide to detect very early resorptions; data collected were used only to determine the incidence of pregnancy and the number of females with total resorptions.

Live fetuses were weighed, sexed and examined for external alterations. For each litter, the maximum stunted weight (MSW) was calculated by subtracting the lightest weight from the total weight, dividing by the remaining number of fetuses and multiplying by 0.666. A fetus weighing the same or less than the MSW was considered stunted; its weight vas omitted when the mean litter weight vas calculated. After the evaluations were completed, the fetuses were sacrificed by decapitation and discarded."

"The litter (i.e., the proportion of affected fetuses per litter or the litter mean) was considered the experimental unit for the purpose of statistical evaluation. The level of significance selected was alpha=0.05."

For incidence of pregnancy, clinical observations, maternal mortality, and females with total resorptions: the Cochran-Armitage test was used for linear trend, and Fisher's exact test was used as pair-wise test between groups.

For maternal weight, maternal weight change, and feed consumption: linear combination of dose ranks from ANOVA was used for linear trend, and Dunnett's test when one-way ANOVA was significant was used as pair-wise test between groups.

F1 Male and Female Crl: CD BR Rats