Agronomy Journal -- Powell et al. 96 (2): 433 Figure IG4

Click on image to view larger version.

Fig. 4. Nitrogen-15 concentration in urine and feces of two dry dairy cows after feeding ¹⁵N-enriched urea. (A single dose of ¹⁵N-enriched urea was fed in 1999, and eight doses were fed in 2000.)