PROTEIN REQUIREMENTS OF CATTLE: MITCHELL 



TABLE 1 



Recorded Determinations of the Daily Excretion of Urinary Nitrogen by 

 Farm Animals on Low-Nitrogen or Nitrogen-Free Rations 



Pig 



Investigator and reference 



McCollum and Hoagland(l5) 



McCoIlum and Steenbock(l6) 



Pfeiffer(n) 



Mitchell and Kick(l8) 

 McCollum and Steenbock(16) 

 MitcheU and Kick(l8) 



McCollum and Hoagland(15) 



McCollum and Steenbock(l6) 



PfeifferC") 



McCollum and Steenbock(i6) 



U U li 



Morgen et al (19) 

 McCollum and Steenbock(l6) 



Steenbock, Nelson and Hart(14) 

 Honcamp, Koudela and Miiller(l2) 

 Hart, Humphrey and Morrison (13) 

 Honcamp, Koudela and Miiller(l2) 

 Copenhagen investigators (H) 

 Hart, Humphrey and Morrison(13) 

 Copenhagen investigators (H) 



Morgen, Beger and Westhauser(19) 



a (( (< u 



« " « « (20) 



a it (t <t 



u u u u (19) 



« « « « (20) 



(19) 

 (20) 

 (19) 



Voltz(21) 



Scheunert, Klein and Steuber(22) 



