C. Crowther and H. E. Woodman 



51 



Table V. Nitrogen-balances for Cow D in period of parlurition. 



Daily ration: 21-5 lb. of seeds hay + linseed cake (for amounts on difi'crcnt days 



see Table). 



Average including N of calf 

 and afterbirth ... 



91-8 



... 252-5 _ _ _ 344.3 



* 1 lb. linseed cake contained 399-0 gm. dry matter and 19-93 gm. N. 

 I This figure gives N of urine + fluids + washings. Loss in weight of Cow D durmg this 

 period was 161 lb. 



Cow D calved on the morning of June 17th, 1919 (day 587), the 

 period of gestation being 284 days. The weight of the calf was 84 lb. 

 Estimating the protein-content of the calf at 16 per cent.^, its nitrogen- 

 content would be 975 gm. The placental fluid, urine and washings were 

 collected together and analysed. The placenta weighed 11-5 lb. and had 

 a nitrogen-content of 74-6 gm. {= 1-43 per cent. N in placenta). 



Taking the figure 2-4gm. as representing the rate of storage of nitrogen 

 per day during the period of i^regnancy, it follows that the total storage 

 of nitrogen by Cow D during the period of gestation was apjjroximately : 



Up to day 579 ... ... 665 gm. 



From day 580 to parturition 108 ,, 

 Total 773 „ 

 The losses of nitrogen during parturition were approximately: 



In calf ... ... ... 975 gm. 



In placenta, etc. 



Total 



75 



1050 



Vide Armsby, The Nutrition of Farm Animals, p. 62. 



4—2 



