The Protein Requirements of Dairy Cows
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1922 edition. Excerpt: ...comparable. Closer agreement could hardly have been attained than that secured in the three medium and low protein comparisons; and the results in the other two comparisons are quite satisfactory. In view of the fact that the experimental error incident to the short alternation system of feeding trials as conducted at this Station as determined by very many years of careful experimentation approximates 1.5 percent, ' there seems no reason to question the essential accuracy of the measure afforded by the single year's trials with relatively few cows, made in 1912-13 and 1913-14, assuming that the method itself is capable of yielding accurate results. The question now arises as to the relative merits as producers of milk of these three rations as judged by the short alternation system. Certain points stand out clearly. (1) The more protein, the more milk, _invariably. The daily ration containing from 11/2 to 1210 pounds of digestible protein made more milk and total solids than did one containing from 11/1 to 1% pounds; the daily ration containing from 21/10 to 23/8 pounds of digestible protein made more milk and total solids than did one containing from 17/10 to 1210 pounds; and the daily ration containing from 2510 to 21/2 pounds digestible protein (and in one case, 1913-14, when heifers were fed, 1% pounds digestible protein) made more milk and total solids than did one containing 11/2 pounds digestible protein (or 1% pounds in the 1913-14 heifer trial). (2) The quality of the milk was not materially affected. However, it is interesting to note that in eight cases out of nine, the casein contents of the milk made when relatively high nitrogenous rations were fed were somewhat higher than when the less proteinous rations were...
- 189 x 246 x 4mm | 145g
- 13 Sep 2013
- United States
- black & white illustrations