Vet World Vol.15 February-2022 Article-13
Research Article
Veterinary World, 15(2): 331-340
https://doi.org/10.14202/vetworld.2022.331-340
Effects of urea supplementation on ruminal fermentation characteristics, nutrient intake, digestibility, and performance in sheep: A meta-analysis
2. Animal Feed and Nutrition Modelling Research Group, Faculty of Animal Science, IPB University, Bogor 16680, Indonesia.
3. Department of Animal Science, Faculty of Agriculture, Erciyes University, Kayseri 38039, Turkey.
4. Department of Animal Science, Graduate School of Biosphere Science, Hiroshima University, 1-4-4 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8528, Japan.
5. Department of Animal Science, UIN Sultan Syarif Kasim, Pekanbaru 28293, Indonesia.
6. Department of Animal Nutrition and Feed Technology, Faculty of Animal Science, IPB University, Bogor 16680, Indonesia.
Background and Aim: As a non-protein nitrogen source, urea is a popular, low cost, and easily obtained protein supplement. The objective of the present study was to perform a meta-analysis of the effects of urea supplementation on rumen fermentation and sheep performance.
Materials and Methods: A total of 32 experiments from 21 articles were compiled into a dataset. The levels of dietary urea varied from 0 to 31 g/kg of dry matter (DM). Parameters observed were rumen fermentation product, nutrient intake, nutrient digestibility, and sheep performance. This dataset was analyzed using a mixed model methodology, with urea supplementation levels as fixed effects and the different experiments as random effects.
Results: Increasing levels of urea were associated with increases (p=0.008) in rumen pH, butyrate (C4) production, and ammonia (NH3–N) concentration. Urea supplementation had minor effects on total volatile fatty acids (p=0.242), total protozoa (p=0.429), and the microbial N supply (p=0.619), but tended to increase methane production (CH4; p<0.001). Supplementation of urea increased the intake of dry matter (DM; p=0.004) and crude protein (CP; p=0.001). Digestibility parameters, such as DM digestibility (DMD) and CP digestibility (CPD), also increased (p<0.01) as a result of urea supplementation. Retained N (p=0.042) and N intake (p<0.001) were higher with increasing levels of urea supplementation. In terms of animal performance, supplementation of urea increased average daily gain (ADG; p=0.024), but decreased the hot carcass weight percentage (p=0.017).
Conclusion: This meta-analysis reports the positive effects of urea supplementation on rumen fermentation products (i.e., pH, C4, and NH3–N), intake (DM, CP, and N), digestibility (DMD and CPD), and ADG in sheep. Keywords: meta-analysis, sheep, supplementation, urea.
Keywords: meta-analysis, sheep, supplementation, urea.
How to cite this article: Wahyono T, Sholikin MM, Konca Y, Obitsu T, Sadarman S, Jayanegara A (2022) Effects of urea supplementation on ruminal fermentation characteristics, nutrient intake, digestibility, and performance in sheep: A meta-analysis, Veterinary World, 15(2): 331-340.
Received: 19-07-2021 Accepted: 12-01-2022 Published online: 15-02-2022
Corresponding author: Teguh Wahyono E-mail: teguhwahyono@batan.go.id
DOI: 10.14202/vetworld.2022.331-340
Copyright: Wahyono, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.