The Dairy Cow Scientific Findings. 383 



In another case a mature cow so fed as to be excessively fat at 

 calving was for a time thereafter given food only sufficient for a dry 

 cow. Beginning with 21 Ibs. of milk daily she was giving 19.5 Ibs. 

 at the end of 30 days of poor feeding, during which time she lost 

 115 Ibs. in weight. Eckles estimates that the 43 Ibs. of fat and 53 

 Ibs. of other solids yielded in the milk during this time must have 

 come from her body tissues. During this period her milk averaged 

 6.9 per ct. fat. "Within 48 hours after her feed was later increased 

 it declined about 2 per ct. 



604. Withholding lime. At the Wisconsin Station 1 Hart, McCol- 

 lum, and Humphrey fed an 1150-lb. cow producing about 30 Ibs. 

 of milk daily a liberal ration save that it lacked lime. It was found 

 that there went into the milk daily about 20 grams of lime (CaO) 

 and into the solid excrement and urine, principally the former, 

 about 30 grams, the latter loss being due to the normal changes 

 (metabolism) taking place in the body. In all about 50 grams, or 

 nearly 2 ounces, of lime disappeared daily from the body of this 

 cow, only one-half of which could have been furnished by the lime 

 in the food. During the trial, which lasted 110 days, this cow main- 

 tained a good flow of milk and continued to put the normal amount 

 of lime into it. It was calculated that during the trial she gave off 

 in milk and excrement 5.5 Ibs. more lime than she received in her 

 food. It was estimated that her skeleton contained about 24.2 Ibs. 

 of lime at the start, and this being true, this cow gave up in 110 days 

 about 25 per ct. of all the lime in her skeleton! Here is a striking 

 illustration of the overpowering force of maternity. (89) 



605. Protein-rich rations. The extensive experiments of the Co- 

 penhagen Station, 2 covering observations with about 2,000 Danish 

 cows and extending over 10 years, appear to show that the normal fat 

 percentage of the milk was raised possibly as much as 0.1 per ct. thru 

 the influence of the highly nitrogenous rations fed. While such an 

 increase is too small to be recognized by the dairyman in his practical 

 work, it is possibly of deep significance and far-reaching importance 

 for the student and breeder looking to the permanent enrichment of 

 the milk of a strain or breed of dairy cattle. 



606. Feeding fat. In 2 trials at the Cornell Station, 3 Wing fed 

 tallow to 10 cows while on pasture or on winter feed. Beginning with 

 a small amount, the allowance of tallow was gradually increased 



1 Research Bui. 5. 3 Bui 92 



z Kpt. 45 ; Woll, Wis. Sta., Bui. 116. 



