Slow-release non-protein nitrogen sources in animal nutrition: A review.
Level 5 - mechanism / opinion, no new human data
Narrative review of animal nutrition literature without systematic methodology (graded by design analogy)
PubMed 39027513 · doi:10.1016/j.heliyon.2024.e33752
What was done
This narrative review synthesized literature on slow-release non-protein nitrogen sources, particularly slow-release urea, as dietary nitrogen supplements for ruminants to optimize rumen microbial protein synthesis and reduce feed costs.
What was found
Rumen bacteria obtain between 40% and 95% of their nitrogen requirements from ammonia depending on diet. Slow-release urea avoids the ammonia toxicity seen with standard rapid-release urea by matching nitrogen release to ruminal fiber digestion. According to the reviewed studies, slow-release urea demonstrated no negative effects on digestibility, rumen parameters, milk production, or overall livestock performance. No specific quantitative effect sizes or pooled comparative metrics were provided in the abstract.
Why it matters
Slow-release urea offers a viable strategy to substitute expensive dietary plant proteins without triggering acute ammonia toxicity or impairing milk and animal yield.
Limits
The abstract describes a non-systematic narrative review without specified search criteria, inclusion standards, or study counts. No statistical effect estimates, variance measures, or species-specific safety limits are reported.
Cited by
- supports Cattle and other ruminants obtain their protein by fermenting fiber into microbes, which serve as the actual protein source for the animal.