Chronic Toxicity Studies

• Groups of 50 males and 50 females are treated with the test substance by dosed feed or water at 3 dose levels for 104 weeks; an untreated feed/water control group is also included (400 animals)
• A satellite group of 20 males and 20 females at the high dose and 10 males and 10 females in the control group are also included for evaluation of non-neoplastic toxicity after 52 weeks (60 additional animals)
• Study measurements include weekly clinical observations; body weights weekly for 13 weeks and monthly thereafter; weekly food and water consumption; and ophthalmological examination pretest and at study termination
• Hematology and serum clinical chemistry, on all animals at termination and in 10/sex/dose at 3, 6, 12, and 18 months; urinalysis in 10/sex/dose at 12 months and at termination
• Necropsies are performed on any animals that die or upon termination; weights are recorded for major organs
• Full histopathological examinations are conducted on the control and high-dose groups (main study and satellite groups) and on any unscheduled deaths
• Target organs are examined in the intermediate groups

• Groups of 15 males and 15 females are treated with the test substance by dosed feed or water at 3 dose levels for 104 weeks; an untreated feed/water control group is also included (120 animals)
• Study measurements include weekly clinical observations; body weights weekly; weekly food and water consumption
• Hematology and serum clinical chemistry on all animals at termination
• Necropsies are performed on any animals that die or upon termination; weights are recorded for major organs
• Full histopathological examinations are conducted on the control and high-dose groups and on any unscheduled deaths
• Target organs are examined in the intermediate groups