PEMANFAATAN NITRAT (NO3-) SEBAGAI SUPLEMEN PAKAN TERNAK RUMINANSIA: STUDI META ANALISIS IN VITRO

Utilization of Nitrat (NO3-) as a Feed Supplement in Ruminant Nutrition: A Meta-Analysis Study

Authors

  • Siti Hadnita Rizkilia Asti Program Studi Ilmu Peternakan, Fakultas Peternakan, Universitas Padjadjaran
  • Ujang Hidayat Tanuwiria Program Studi Ilmu Peternakan, Fakultas Peternakan, Universitas Padjadjaran
  • Yulianri Rizki Yanza Program Studi Ilmu Peternakan, Fakultas Peternakan, Universitas Padjadjaran

DOI:

https://doi.org/10.37090/jwputb.v9i2.2106

Abstract

Kebutuhan akan pakan sumber protein bagi ternak ruminansia semakin meningkat seiring dengan meningkatnya produktivitas ternak. Kondisi tersebut menjadi suatu tantangan bagi peternak ruminansia mengingat terbatasnya ketersediaan pakan sumber protein dengan harga yang terjangkau. Salah satu solusi yang dapat dilakukan adalah dengan menyediakan pakan sumber protein alternatif yang didapatkan dari Nitrogen Non-Protein (NPN). Nitrat (NO3-) merupakan salah satu NPN yang berpotensi untuk menyediakan sumber amonia yang penting bagi sintesis protein mikroba di dalam rumen. Akan tetapi, pengaruh konsentrasi nitrat terhadap fermentasi rumen masih belum dapat disimpulkan secara pasti. Penelitian ini bertujuan untuk mengetahui pengaruh nitrat terhadap karakteristik fermentasi rumen dan kecernaan nutrien in vitro dengan pendekatan meta analisis. Sebanyak 38 publikasi yang mencakup 99 studi in vitro dimasukkan dalam penelitian ini menjadi suatu database dan dianalisis secara statistik dengan menggunakan model campuran, di mana percobaan yang berbeda dianggap sebagai efek acak dan faktor terkait nitrat dianggap sebagai efek tetap. Hasil menunjukkan bahwa suplementasi nitrat secara signifikan (P <0,05) meningkatkan NH3-N, menurunkan kecernaan protein kasar (KcPK) dan TVFA/gram BK, serta cenderung berpengaruh signifikan (P = 0,09) menurunkan kecernaan bahan kering (KcBK). Kesimpulan dari penelitian ini adalah penambahan nitrat dalam pakan ternak ruminansia dapat memodulasi karakteristik fermentasi rumen dan kecernaan nutrien.

Kata kunci: Karakteristik fermentasi rumen, kecernaan nutrien, nitrat, produksi gas metan, produksi gas total.

Downloads

Download data is not yet available.

References

Adejoro, F. A., dan Hassen, A. (2017). Effect of Supplementing or Treating Eragrostis curvula Hay With Urea or Nitrate on Its Digestibility and In Vitro Fermentation. South African Journal of Animal Science, 47(2), 168–177. https://doi.org/10.4314/sajas.v47i2.8

Asanuma, N., Yokoyama, S., dan Hino, T. (2015). Effects of Nitrate Addition to a Diet on Fermentation and Microbial Populations in the Rumen of Goats, With Special Reference to Selenaomonas ruminantium Having the Ability to Reduce Nitrate and Nitrite. Animal Science Journal, 86(4), 378–384. https://doi.org/10.1111/asj.12307

Božic, A. K., Anderson, R. C., Carstens, G. E., Ricke, S. C., Callaway, T. R., Yokoyama, M. T., Wang, J. K., dan Nisbet, D. J. (2009). Effects of The Methane-inhibitors Nitrate, Nitroethane, Lauric acid, Lauricidin® and The Hawaiian Marine Algae Chaetoceros on Ruminal Fermentation In Vitro. Bioresource Technology, 100(17), 4017–4025. https://doi.org/10.1016/j.biortech.2008.12.061

Braidot, M., Sarnataro, C., dan Spanghero, M. (2023). Dynamics of In Vitro Rumen Methane Production After Nitrate Addition. Archives of Animal Nutrition, 77(6), 512–523. https://doi.org/10.1080/1745039X.2023.2282348

Bryant, A. M. (1965). The Effect of Nitrate on the In Vitro Fermentation of Glucose by Rumen Liquor. New Zealand Journal of Agricultural Research, 8(1), 118–125. https://doi.org/10.1080/00288233.1965.10420028

Capelari, M., Johnson, K. A., Latack, B., Roth, J., dan Powers, W. (2018). The Effect of Encapsulated Nitrate and Monensin on Ruminal Fermentation Using a Semi-Continuous Culture System. Journal of Animal Science, 96(8), 3446–3459. https://doi.org/10.1093/jas/sky211

Capelari, M., dan Powers, W. (2017). The Effect of Nitrate and Monensin on In Vitro Ruminal Fermentation. Journal of Animal Science, 95(11), 5112–5123. https://doi.org/10.2527/jas2017.1657

Chagas, J. C., Ramin, M., dan Krizsan, S. J. (2019). In Vitro Evaluation of Different Dietary Methane Mitigation Strategies. Animals, 9(12), 1120. https://doi.org/10.3390/ani9121120

Choudhury, P. K., Jena, R., Tomar, S. K., dan Puniya, A. K. (2022). Reducing Enteric Methanogenesis through Alternate Hydrogen Sinks in the Rumen. Methane, 1(4), 320–341. https://doi.org/10.3390/methane1040024

Correa, A. C., Trachsel, J., Allen, H. K., Corral-Luna, A., Gutierrez-Bañuelos, H., Ochoa-Garcia, P. A., Ruiz-Barrera, O., Hume, M. E., Callaway, T. R., Harvey, R. B., Beier, R. C., Anderson, R. C., dan Nisbet, D. J. (2017). Effect of Sole or Combined Administration of Nitrate and 3-Nitro-1-Propionic Acid on Fermentation and Salmonella Survivability in Alfalfa-Fed Rumen Cultures In Vitro. Bioresource Technology, 229, 69–77. https://doi.org/10.1016/j.biortech.2017.01.012

Cottle, D. J., Nolan, J. V., dan Wiedemann, S. G. (2011). Ruminant Enteric Methane Mitigation: a Review. Animal Production Science, 51(6), 491–514. https://doi.org/10.1071/AN10163

Feng, X. Y., Dijkstra, J., Bannink, A., van Gastelen, S., France, J., dan Kebreab, E. (2020). Antimethanogenic Effects of Nitrate Supplementation in Cattle: A Meta-Analysis. Journal of Dairy Science, 103(12), 11375–11385. https://doi.org/10.3168/jds.2020-18541

Guo, W. S., Schaefer, D. M., Guo, X. X., Ren, L. P., dan Meng, Q. X. (2009). Use of Nitrate-nitrogen as a Sole Dietary Nitrogen Source to Inhibit Ruminal Methanogenesis and to Improve Microbial Nitrogen Synthesis In vitro. Asian-Australasian Journal of Animal Sciences, 22(4), 542–549. https://doi.org/10.5713/ajas.2009.80361

Guo, Y., Hassan, F., Li, M., Tang, Z., Peng, L., Peng, K., dan Yang, C. (2022a). Effect of Hydrogen-Consuming Compounds on In Vitro Ruminal Fermentation, Fatty Acids Profile, and Microbial Community in Water Buffalo. Current Microbiology, 79(8), 220. https://doi.org/10.1007/s00284-022-02904-7

Guo, Y., Hassan, F., Li, M., Xie, H., Peng, L., Tang, Z., dan Yang, C. (2022b). Effect of Sodium Nitrate and Cysteamine on In Vitro Ruminal Fermentation, Amino Acid Metabolism and Microbiota in Buffalo. Microorganisms, 10, 2038. https://doi.org/10.3390/microorganisms10102038

Guyader, J., Tavendale, M., Martin, C., dan Muetzel, S. (2016). Dose-Response Effect of Nitrate on Hydrogen Distribution Between Rumen Fermentation End Products: An In Vitro Approach. Animal Production Science, 56(3), 224. https://doi.org/10.1071/AN15526

Guyader, J., Ungerfeld, E. M., dan Beauchemin, K. A. (2017). Redirection of Metabolic Hydrogen by Inhibiting Methanogenesis in the Rumen Simulation Technique (RUSITEC). Frontiers in Microbiology, 8. https://doi.org/10.3389/fmicb.2017.00393

Hassan, F., Guo, Y., Li, M., Tang, Z., Peng, L., Liang, X., dan Yang, C. (2021). Effect of Methionine Supplementation on Rumen Microbiota, Fermentation, and Amino Acid Metabolism in In Vitro Cultures Containing Nitrate. Microorganisms, 9(8), 1717. https://doi.org/10.3390/microorganisms9081717

Henry, D. D., Ciriaco, F. M., Araujo, R. C., Garcia-Ascolani, M. E., Fontes, P. L. P., Oosthuizen, N., Sanford, C. D., Schulmeister, T. M., Ruiz-Moreno, M., Lamb, G. C., dan DiLorenzo, N. (2021). Encapsulated Nitrate Replacing Soybean Meal Changes In Vitro Ruminal Fermentation and Methane Production in Diets Differing in Concentrate-to-Forage Ratio. Animal, 15(5), 100195. https://doi.org/10.1016/j.animal.2021.100195

Jayanegara, A., Wina, E., dan Takahashi, J. (2014). Meta-analysis on Methane Mitigating Properties of Saponin-rich Sources in the Rumen: Influence of Addition Levels and Plant Sources. Asian-Australasian Journal of Animal Sciences, 27(10), 1426–1435. https://doi.org/10.5713/ajas.2014.14086

Joch, M., Vadroňová, M., Češpiva, M., Zabloudilová, P., Výborná, A., Tyrolová, Y., Kudrna, V., Tichá, D., Plachý, V., dan Hroncová, Z. (2023). Capric and Lauric Acid Mixture Decreased Rumen Methane Production, While Combination With Nitrate Had No Further Benefit in Methane Reduction. Annals of Animal Science, 23(3), 799–808. https://doi.org/10.2478/aoas-2023-0010

Latham, E. A., Anderson, R. C., Pinchak, W. E., dan Nisbet, D. J. (2016). Insights on Alterations to the Rumen Ecosystem by Nitrate and Nitrocompounds. Frontiers in Microbiology, 7. https://doi.org/10.3389/fmicb.2016.00228

Lee, C., Araujo, R. C., Koenig, K. M., dan Beauchemin, K. A. (2017). In Situ and In Vitro Evaluations of a Slow-Release Form of Nitrate for Ruminants: Nitrate Release Rate, Rumen Nitrate Metabolism, and the Production of Methane, Hydrogen, and Nitrous Oxide. Animal Feed Science and Technology, 231, 97–106. https://doi.org/10.1016/j.anifeedsci.2017.07.005

Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gøtzsche, P. C., Ioannidis, J. P. A., Clarke, M., Devereaux, P. J., Kleijnen, J., dan Moher, D. (2009). The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration. Annals of Internal Medicine , 151(4), 65–94.

Lin, M., Schaefer, D. M., Guo, W. S., Ren, L. P., dan Meng, Q. X. (2011). Comparisons of In vitro Nitrate Reduction, Methanogenesis, and Fermentation Acid Profile among Rumen Bacterial, Protozoal and Fungal Fractions. Asian-Australasian Journal of Animal Sciences, 24(4), 471–478. https://doi.org/10.5713/ajas.2011.10288

Lin, M., Schaefer, D. M., Zhao, G. Q., dan Meng, Q. X. (2013). Effects of Nitrate Adaptation by Rumen Inocula Donors and Substrate Fiber Proportion on in Vitro Nitrate Disappearance, Methanogenesis, and Rumen Fermentation Acid. Animal, 7(7), 1099–1105. https://doi.org/10.1017/S1751731113000116

Lund, P., Dahl, R., Yang, H. J., Hellwing, A. L. F., Cao, B. B., dan Weisbjerg, M. R. (2014). The Acute Effect of Addition of Nitrate on in Vitro and in Vivo Methane Emission in Dairy Cows. Animal Production Science, 54(9), 1432. https://doi.org/10.1071/AN14339

Mamvura, C. I., Cho, S., Mbiriri, D. T., Lee, H. G., dan Choi, N. J. (2014). Effect of Encapsulating Nitrate in Sesame Gum on In vitro Rumen Fermentation Parameters. Asian-Australasian Journal of Animal Sciences, 27(11), 1577–1583. https://doi.org/10.5713/ajas.2014.14280

Marais, J. P., Therion, J. J., Mackie, R. I., Kistner, A., dan Dennison, C. (1988). Effect of Nitrate and Its Reduction Products on the Growth and Activity of the Rumen Microbial Population. British Journal of Nutrition, 59(2), 301–313. https://doi.org/10.1079/bjn19880037

Mbiriri, D. T., Cho, S., Mamvura, C. I., dan Choi, N. J. (2017). Effects of a Blend of Garlic Oil, Nitrate, and Fumarate on In Vitro Ruminal Fermentation and Microbial Population. Journal of Animal Physiology and Animal Nutrition, 101(4), 713–722. https://doi.org/10.1111/jpn.12508

McAllister, T. A., Okine, E. K., Mathison, G. W., dan Cheng, K. J. (1996). Dietary, Environmental and Microbiological Aspects of Methane Production in Ruminants. Can J Anim Sci, 76, 231–243.

Mejia-Turcios, S. E., Osorio-Doblado, A. M., Ciriaco, F. M., Urso, P. M., Araujo, R. C., Woerner, D. R., Johnson, B. J., Dubeux, J. C. B., Sarturi, J. O., DiLorenzo, N., dan Henry, D. D. (2021). Effects of Bismuth Subsalicylate and Encapsulated Calcium-Ammonium Nitrate on Feedlot Beef Cattle Production. Journal of Animal Science, 99(10). https://doi.org/10.1093/jas/skab269

Morsy, T. A., Gouda, G. A., dan Kholif, A. E. (2022). In Vitro Fermentation and Production of Methane and Carbon Dioxide from Rations Containing Moringa oleifera Leaf Silage as a Replacement for Soybean Meal: In Vitro Assessment. Environmental Science and Pollution Research, 29(46), 69743–69752. https://doi.org/10.1007/s11356-022-20622-2

Natel, A. S., Abdalla, A. L., Araujo, R. C. D., Paim, T. P., Abdallafilho, A. L., Louvandini, P., Lima, M. K., dan Piza, P. (2022). Encapsulated Nitrate Replacing Soybean Meal in Diets With and Without Monensin on In Vitro Ruminal Fermentation. Anais Da Academia Brasileira de Ciências, 94(4). https://doi.org/10.1590/0001-3765202220200213

Natel, A. S., Abdalla, A. L., de Araujo, R. C., McManus, C., Paim, T. d. P., de Abdalla Filho, A. L., Louvandini, P., dan Nazato, C. (2019). Encapsulated Nitrate Replacing Soybean Meal Changes In Vitro Ruminal Fermentation and Methane Production in Diets Differing in Concentrate-to-Forage Ratio. Animal Science Journal, 90(10), 1350–1361. https://doi.org/10.1111/asj.13251

Nguyen, S. H., Li, L., dan Hegarty, R. S. (2015). Effects of Rumen Protozoa of Brahman Heifers and Nitrate on Fermentation and In vitro Methane Production. Asian-Australasian Journal of Animal Sciences, 29(6), 807–813. https://doi.org/10.5713/ajas.15.0641

Olijhoek, D. W., Hellwing, A. L. F., Brask, M., Weisbjerg, M. R., Højberg, O., Larsen, M. K., Dijkstra, J., Erlandsen, E. J., dan Lund, P. (2016). Effect of Dietary Nitrate Level on Enteric Methane Production, Hydrogen Emission, Rumen Fermentation, and Nutrient Digestibility in Dairy Cows. Journal of Dairy Science, 99(8), 6191–6205. https://doi.org/10.3168/jds.2015-10691

Ortiz-Chura, A., Gere, J., Marcoppido, G., Depetris, G., Cravero, S., Faverín, C., Pinares-Patiño, C., Cataldi, A., dan Cerón-Cucchi, M. E. (2021). Dynamics of the Ruminal Microbial Ecosystem and Inhibition of Methanogenesis and Propiogenesis in Response to Nitrate Feeding to Holstein Calves. Animal Nutrition, 7(4), 1205–1218. https://doi.org/10.1016/j.aninu.2021.07.005

Owens, F. N., Pas, S. Q., dan Sapienza, D. A. (2014). Protein Nutrition of Ruminants Classical CP Requirements. The Professional Animal Scientist, 30, 150–159.

Patra, A. K., dan Yu, Z. (2013). Effective Reduction of Enteric Methane Production by a Combination of Nitrate and Saponin Without Adverse Effects on Feed Degradability, Fermentation, or Bacterial and Archaeal Communities of the Rumen. Bioresource Technology, 148, 352–360. https://doi.org/10.1016/j.biortech.2013.08.140

Patra, A. K., dan Yu, Z. (2015a). Effects of Adaptation of In vitro Rumen Culture to Garlic Oil, Nitrate, and Saponin and Their Combinations on Methanogenesis, Fermentation, and Abundances and Diversity of Microbial Populations. Frontiers in Microbiology, 6. https://doi.org/10.3389/fmicb.2015.01434

Patra, A. K., dan Yu, Z. (2015b). Effects of Garlic Oil, Nitrate, Saponin, and Their Combinations Supplemented to Different Substrates on In Vitro Fermentation, Ruminal Methanogenesis, and Abundance and Diversity of Microbial Populations. Journal of Applied Microbiology, 119(1), 127–138. https://doi.org/10.1111/jam.12819

Putri, E. M., Zain, M., Warly, L., dan Hermon, H. (2021). Effects of Rumen-Degradable-to-Undegradable Protein Ratio in Ruminant Diets on In Vitro Digestibility, Rumen Fermentation, and Microbial Protein Synthesis. Veterinary World, 14(3), 640–648. https://doi.org/10.14202/VETWORLD.2021.640-648

Rohma, M. R., Zubairi, I., Aryono, A. D., Nasrullah, L., dan Widianingrum, D. C. (2021). Nitrat: Karakteristik Antinutrisi, Dampak Negatif, Potensi Aditif, dan Efektivitas Agen Defaunasi. ANIMPRO: Conference of Applied Animal Science Proceeding Series, 24–31. https://doi.org/10.25047/animpro.2021.3

Sakthivel, P. C., Kamra, D. N., Agarwal, N., dan Chaudhary, L. C. (2012). Effect of Sodium Nitrate and Nitrate Reducing Bacteria on In vitro Methane Production and Fermentation with Buffalo Rumen Liquor. Asian-Australasian Journal of Animal Sciences, 25(6), 812–817. https://doi.org/10.5713/ajas.2011.11383

Sar, C., Mwenya, B., Pen, B., Morikawa, R., Takaura, K., Kobayashi, T., dan Takahashi, J. (2005). Effect of Nisin on Ruminal Methane Production and Nitrate/Nitrite Reduction In Vitro. Australian Journal of Agricultural Research, 56(8), 803. https://doi.org/10.1071/AR04294

Sharifi, M., Taghizadeh, A., Hosseinkhani, A., Palangi, V., Macit, M., Salem, A. Z. M., Elghndour, M. M. M. Y., dan Abachi, S. (2022). Influence of Nitrate Supplementation on In-Vitro Methane Emission, Milk Production, Ruminal Fermentation, and Microbial Methanotrophs in Dairy Cows Fed at Two Forage Levels. Annals of Animal Science, 22(3), 1015–1026. https://doi.org/10.2478/aoas-2021-0087

St-Pierre, N. R. (2001). Invited Review. Integrating Quantitative Findings from Multiple Studies Using Mixed Model Methodology. Journal of Dairy Science, 84(4), 741–755. https://doi.org/10.3168/jds.S0022-0302(01)74530-4

Sun, Y. K., Yan, X. G., Ban, Z. B., Yang, H. M., Hegarty, R. S., dan Zhao, Y. M. (2017). The Effect of Cysteamine Hydrochloride and Nitrate Supplementation on In-Vitro and In-Vivo Methane Production and Productivity of Cattle. Animal Feed Science and Technology, 232, 49–56. https://doi.org/10.1016/j.anifeedsci.2017.03.016

Tadele, Y., dan Amha, N. (2015). Use of Different Non Protein Nitrogen Sources in Ruminant Nutrition: a Review. 29.

Takahashi, J. (2011). Some Prophylactic Options to Mitigate Methane Emission from Animal Agriculture in Japan. Asian-Australasian Journal of Animal Sciences, 24(2), 285–294. https://doi.org/10.5713/ajas.2011.r.03

Tandon, T., Siddique, R. A., dan Ambwani, T. (2008). Role of Bypass Proteins in Ruminant Production. Dairy Planner, 4(10), 11–14. https://doi.org/10.13140/RG.2.2.16615.04003

Thao, N. T., Phesatcha, K., Matra, M., Phesatcha, B., dan Wanapat, M. (2022). Sources of Rumen Enhancers Including Nitrate, Chitosan Extract, and Shrimp Shell Meal Could Modulate Nutrient Degradability and In Vitro Gas Fermentation. Journal of Applied Animal Research, 50(1), 394–399. https://doi.org/10.1080/09712119.2022.2088540

Ungerfeld, E. M. (2020). Metabolic Hydrogen Flows in Rumen Fermentation: Principles and Possibilities of Interventions. Frontiers in Microbiology, 11, 589. https://doi.org/10.3389/fmicb.2020.00589

Vadroňová, M., Šťovíček, A., Jochová, K., Výborná, A., Tyrolová, Y., Tichá, D., Homolka, P., dan Joch, M. (2023). Combined effects of nitrate and medium-chain fatty acids on methane production, rumen fermentation, and rumen bacterial populations in vitro. Scientific Reports, 13(1), 21961. https://doi.org/10.1038/s41598-023-49138-6

van Zijderveld, S. M., Gerrits, W. J. . J., Dijkstra, J., Newbold, J. R., Hulshof, R. B. A., dan Perdok, H. B. (2011). Persistency of Methane Mitigation by Dietary Nitrate Supplementation in Dairy Cows. Journal of Dairy Science, 94(8), 4028–4038. https://doi.org/10.3168/jds.2011-4236

Wang, M., Wang, R., Yang, S., Deng, J. P., Tang, S. X., dan Tan, Z. L. (2016). Effects of Three Methane Mitigation Agents on Parameters of Kinetics of Total and Hydrogen Gas Production, Ruminal Fermentation, and Hydrogen Balance Using In Vitro Technique. Animal Science Journal, 87(2), 224–232. https://doi.org/10.1111/asj.12423

Wu, H., Meng, Q., Zhou, Z., dan Yu, Z. (2019). Ferric Citrate, Nitrate, Saponin and Their Combinations Affect In Vitro Ruminal Fermentation, Production of Sulphide and Methane and Abundance of Select Microbial Populations. Journal of Applied Microbiology, 127(1), 150–158. https://doi.org/10.1111/jam.14286

Yang, C., McKain, N., McCartney, C. A., dan Wallace, R. J. (2019). Consequences of Inhibiting Methanogenesis on the Biohydrogenation of Fatty Acids in Bovine Ruminal Digesta. Animal Feed Science and Technology, 254, 114189. https://doi.org/10.1016/j.anifeedsci.2019.05.012

Yanza, Y. R., Szumacher-Strabel, M., Jayanegara, A., Kasenta, A. M., Gao, M., Huang, H., Patra, A. K., Warzych, E., dan Cieślak, A. (2021). The Effects of Dietary Medium-chain Fatty Acids on Ruminal Methanogenesis and Fermentation In Vitro and In Vivo: A Meta-analysis. Journal of Animal Physiology and Animal Nutrition, 105(5), 874–889. https://doi.org/10.1111/jpn.13367

Yu, G., Beauchemin, K. A., dan Dong, R. (2021). A Review of 3-Nitrooxypropanol for Enteric Methane Mitigation from Ruminant Livestock. Animals, 11(12), 3540. https://doi.org/10.3390/ani11123540

Zhou, Z., Yu, Z., dan Meng, Q. (2012). Effects of Nitrate on Methane Production, Fermentation, and Microbial Populations in In Vitro Ruminal Cultures. Bioresour Technol, 103(1), 173–179. https://doi.org/10.1016/j.biortech.2011.10.013

Zurak, D., Kristina, K., dan Aladrović, J. (2023). Metabolism and Utilisation of Non-Protein Nitrogen Compounds in Ruminants: a Review. Journal of Central European Agriculture, 24(1), 1–14. https://doi.org/10.5513/JCEA01/24.1.3645

Downloads

Published

11-07-2025

How to Cite

Siti Hadnita Rizkilia Asti, et al. “PEMANFAATAN NITRAT (NO3-) SEBAGAI SUPLEMEN PAKAN TERNAK RUMINANSIA: STUDI META ANALISIS IN VITRO: Utilization of Nitrat (NO3-) As a Feed Supplement in Ruminant Nutrition: A Meta-Analysis Study ”. Wahana Peternakan, vol. 9, no. 2, July 2025, pp. 329-44, doi:10.37090/jwputb.v9i2.2106.