SEXUAL ACTIVITY OF MALE RABBITS 
TABLE 3 
595 
2. Coefficient of variability of individuals within the litters at three different periods 
SERVICE 
Ist 5th 10th 15th 20th 
AGE zS me = a le 
} iS 5 i) S) 
52 52 52 52 Cm 
as Percent /|29 Percent |93 Percent |= 2 Percent |22| Percent 
= a eee ee ee 
days 
Birth 2610.81=1.01) 2010.78=1.14) 1912.52=1.37) 11/11.48+1.64) 16,8.80+1.05 
30 23)/10.72=1.07) 17) 8.27+=0.96) 19,10.05=1.10) 11) 9.56=1.29) 11/7.89+1.11 
90 23/10.10+1.02) 14) 6.77+0.86| 17| 7.55+0.87| 810.70+1.80) 9/8.94+1.42 
| 
Average. 10.55 8.82 TORTS 10.55 8.56 
The coefficients of variability for all Ist-service litters at birth 
were then added together and this sum was divided by the 
number of litters concerned to secure the coefficient as given in 
table 3. Likewise the coefficients of variability for all 1st-serv- 
ice litters at thirty days were added together and this sum 
divided by the number of litters concerned to obtain the co- 
efficient as given in table 3. This method was used on the weights 
at ninety days to get the coefficient, and a similar procedure 
used on the weights in the other four service groups to obtain 
their respective coefficients. For the information of the reader 
the number of litters concerned in each case is presented in the 
table. MacDowell (14, p. 44) shows in studies on weight of 
adult rabbits that there is less variability within the litters than 
between individuals of different litters. For this reason and be- 
cause we wish to compare progeny of different ancestry, the 
method of expressing the coefficient of variation of the popula- 
tions as the average of the individual litter coefficients of that 
population is considered accurate. 
Table 3 shows that the coefficient of variation in rabbits is 
greater at birth than at any other time during our observations. 
This fact holds good in all service groups. While the coefficient 
on the average is small, it serves to indicate that prenatal nutri- 
tion must be subject to wide variations, otherwise greater uni- 
