Absorption of Non-Protein Nitrogen in Guajillo by White-Tailed Deer


  • Michael J. Mayfield
  • Tyler A. Campbell
  • David G. Hewitt


ammonium, digestibility, guajillo, Acacia berlandieri, nitrogen, Odocoileus virginianus, urea, white-tailed deer


Guajillo (Acacia berlandieri) is an important forage for white-tailed deer (Odocoileus virginianus), but has high concentrations of non-protein nitrogen (N).  To determine if non-protein N is absorbed by deer, 4 diets with different proportions of guajillo were assigned randomly to 4 male deer in a Latin square design and total balance trials were conducted.  Urea and ammonium N were assayed and subtracted from total urinary N, resulting in a pool of N we called uncharacterized N.  Our hypothesis was if non-protein N was absorbed but not used by the deer, the amount of uncharacterized N in urine would increase with increasing amounts of guajillo in the diet.  Uncharacterized N did not differ among diets (F3,6= 2.37, P = 0.169).  Our data suggest non-protein N must have either not been absorbed in the digestive tract, or was converted to amino acids by rumen microbes prior to absorption.




How to Cite

Mayfield, M. J., Campbell, T. A., & Hewitt, D. G. (2016). Absorption of Non-Protein Nitrogen in Guajillo by White-Tailed Deer. Texas Journal of Agriculture and Natural Resources, 17, 53–56. Retrieved from https://txjanr.agintexas.org/index.php/txjanr/article/view/129



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