III. RESULTS: MICE 



Survival 



Estimates of the probabilities of survival for 

 male and female mice fed diets containing nitro- 

 furantoin at the concentrations used in these 

 studies and for controls are shown in Table 23 

 and in the Kaplan and Meier curves in Fig- 

 ure 12. The survival of the control group of fe- 

 male mice was significantly lower than that of 

 both the low and high dose groups. No sig- 

 nificant differences in survival were observed 

 between any groups of male mice. 



Pathology and Statistical Analyses of 

 Results 



This section describes the statistically signifi- 

 cant or biologically noteworthy changes in the 

 incidences of mice with neoplastic or nonneo- 

 plastic lesions of the ovary, hematopoietic 

 system, uterus, liver, testis, epididymis, kidney, 

 and adrenal glands. 



Summaries of the incidences of neoplasms and 

 nonneoplastic lesions, individual animal tumor 

 diagnoses, statistical analyses of primary tu- 

 mors that occurred with an incidence of at least 

 5% in at least one animal group, and historical 

 control incidences for the neoplasms mentioned 

 in this section are presented in Appendixes C 

 and D for male and female mice, respectively. 



TABLE 23. SURVIVAL OF MICE IN THE TWO-YEAR FEED STUDIES OF NITROFURANTOIN 



Control 



1,300 ppm 



2,500 ppm 



MALE (a) 



Animals initially in study 



Nonaccidental deaths before termination (b) 



Killed at termination 



Died during termination period 



Survival P values (c) 



FEMALE (a) 



Animals initially in study 



Nonaccidental deaths before termination (bl 



Killed at termination 



Died during termination period 



Survival P values (c) 



50 

 16 

 33 



1 



0.197 



50 



13 



37 







<0.001 



(a) First day of termination period: 730 



(b) Includes animals killed in a moribund condition 



(c)The result of the life table trend test is in the control column, and the results of the life table pairwise comparisons with 

 .the controls are in the dosed columns. 



Nitrofurantoin, NTPTR 341 



54 



