Vol. 8, No. 10 
Page 5 
The results for Rugel's plantain were inconsistent and seemed to reflect 
changes in the plants, due to maturation. One rabbit gained weight and survived 
on the plantain collected during early July. This sample of plantain was about 
75 percent digestible. Two rabbits lost weight and survived only 12 and 9 days, 
respectively, on plantain collected during the 3rd and 4th weeks of July, 
respectively. The digestibility of plantain, especially the digestibility of its 
protein content, decreased as the month progressed. 
Seasonal fluctuations in digestibility of plant foods, due to maturation of 
plant tissues, are well known in livestock feeding. These fluctuations could be 
important in the food supply of cottontails inhabiting relatively monotonous stands 
of vegetation. In contrast, there is a great variety of plant species in the 
luxurious growth of weeds that commonly follows site-disturbance in Illinois. Due 
to differences in phenology, some of the plant species in these stands of weeds 
should be in a stage of vigorous growth--which usually results in the most digestibl 
forage -- throughout the summer. 
Table 4. Results of digestion trials conducted with young cottontail rabbits, 
July - August, 19^5• 
Crude 
Digestion Coefficients 
Digestible 
Nutrients 
Number 
Protein 
Percent 
Crude 
Energy 
Species 
of 
Trials 
(% dry 
wgt.) 
Dry 
Matter 
C r< j e 
Protein 
Energy 
Protein 
(% dry wgt, 
(cal./gram 
.) dry wgt.) 
Prickly lettuce 
Lactuca scariola 
3 
23.4 
78 
84 
73 
19.6 
3,080 
Chicory 
Cichorium intybus 
2 
18.4 
74 
76 
70 
13.9 
2,747 
Rugel's plantain 
P1antaqo ruqelii 
July 8 - 15 
1 
16.4 
79 
75 
76 
12.2 
2,900 
July 18 - 25 
1 
16.6 
74 
65 
70 
10.8 
2,638 
July 26 - 30 
1 
16.6 
67 
53 
61 
8.8 
2,244 
Smar tweed 
Polyqonum 
pensylvanicum 
1 
23-9 
66 
50 
62 
12.0 
2,542 
Red clover 
Trifolium 
pratense 
1 
22.2 
50 
52 
46 
11.7 
l ,967 
