Environmental Implications of Nitrogen Output on Horse Operations: A Review

Rebecca C. Bott, Elizabeth A. Greene, Nathalie L. Trottier, Carey A. Williams, Michael L. Westendorf, Ann M. Swinker, Sara L. Mastellar, Krishona L. Martinson

Research output: Contribution to journalReview article

5 Scopus citations


Nutrients such as nitrogen (N), which go unused during the digestive process, are then excreted into the environment via urine, gas, or fecal matter. Excess N released in this manner may contribute to a reduction of the quality of air and groundwater sources. Many states have introduced or developed legislation mandating nutrient management plans on livestock operations to reduce environmental N losses. Strategies for reducing the environmental impacts of N on equine operations are twofold, including a reduction in N inputs and better management of N outputs. The practice of precision feeding, or feeding to accurately meet, but not exceed the nutrients requirements of an animal is a plausible method for reducing N inputs. This approach is not widely implemented, as feeding protein in excess of requirements is a common practice in the equine industry. Also, precision feeding is predicated on a body of data containing the nutrient availability and digestibility in different feed sources; data which are not fully elucidated in the horse. Management of N outputs on equine operations is largely based on data extrapolated from other livestock operations as well as a few preliminary efforts on horse farms. The potential impact of equine operations on N losses is explored in this review, shedding light on areas where further research and management strategies are needed.

Original languageEnglish (US)
Pages (from-to)98-106
Number of pages9
JournalJournal of Equine Veterinary Science
Publication statusPublished - Oct 1 2016


All Science Journal Classification (ASJC) codes

  • Equine

Cite this

Bott, R. C., Greene, E. A., Trottier, N. L., Williams, C. A., Westendorf, M. L., Swinker, A. M., ... Martinson, K. L. (2016). Environmental Implications of Nitrogen Output on Horse Operations: A Review. Journal of Equine Veterinary Science, 45, 98-106. https://doi.org/10.1016/j.jevs.2015.08.019