426 



Journal of Agricultural Research 



Vol. IV, No. s 



of the ration is deficient in mineral matter. Cows producing large 

 quantities of milk require considerable mineral matter, especially cal- 

 cium; and as some feeds, like cottonseed hulls, are low in mineral ele- 

 ments, it is thought that prickly-pear is a valuable supplement to 

 such feeds. Cow 5, a strong, vigorous, high-producing animal, when 

 fed a ration with cottonseed hulls as the sole roughage, became so ill in 

 about 10 weeks that it was necessary to change her ration. She showed 

 an abnormal appetite for common salt (sodium chlorid) and upon moving 

 about groaned as if in pain. The treatment ordinarily administered 

 for cases of indigestion afforded no relief, but upon the addition of 

 prickly-pear to her ration she recovered promptly. Cows producing 

 smaller quantities of milk and possessing less robust constitutions, 

 although fed in the same way, remained unaffected. These facts suggest 

 that this cow suffered from a deficiency of mineral elements in her ration. 



EFFECT OF FEEDING PRICKLY-PEAR UPON THE OFFSPRING OF DAIRY COWS 



In order to determine the effect of prickly-pear upon the offspring, 

 the herd was divided into four groups as soon as the feeding experiment 

 was finished. The first group was fed sorghum hay alone as a roughage ; 

 the second, sorghum hay with a medium amount of prickly-pear; the 

 third, sorghum hay with a large quantity of prickly-pear; and the 

 fourth, prickly-pear alone. Grain was fed in such amounts as were 

 necessary to put the cows in good condition at the time of calving 

 The grain ration of the cows receiving prickly-pear alone as rough- 

 age consisted entirely of cottonseed meal ; the cows in the other groups 

 received the same grain mixture that was used in the feeding experi- 

 ment. Except for a period of two or three weeks, when some of the 

 animals were on digestion trials, these rations were continued until the 

 cows freshened, making a period of about five months for each cow. 



Table XVI gives the numbers of the cows in each group, the character 

 of their rations, the length of the gestation period, weight of the dam, 

 the sex and weight of the calf, and some brief notes on the condition of 

 the calf at birth. 



Table XVI. — Effect of feeding prickly-pear upon the offspring of dairy cows 



No. of 

 cow. 



Roughage ration. 



Length 

 of gesta- 

 tion 

 period. 



Weight 

 of dam. 



Sex of 

 calf. 



Birth 

 weight 

 of calf. 



Condition of calf. 



Prickly-pear alone . 

 do 



Heavy prickly-pear. . 



....do 



Medium prickly-pear. 



....do 



do 



do 



No prickly-pear 



do 



do 



Days. 



274 

 279 



272 



276 

 281 

 273 

 279 

 277 

 273 

 272 

 274 



Pounds. 

 912 

 696 



870 



762 



800 

 806 



Male. . . 

 Female 



fMale. . . 

 \FemaIe 



Female 

 ...do.... 

 ...do.... 

 ...do.... 

 ...do.... 



Male. . . 



Female 



Male. .. 



Pounds. 

 59 



Fair. 



Weak, died of white 



scours. 

 /Twin calves, both small 

 \ but vigorous. 

 Fair. 



Big-boned, weak. 

 Strong. 

 Do. 

 Do. 

 Fair. 



Small-boned, vigorous. 

 Small, weak, grew well. 



