Introduction The main factors limiting the consumption of low-quality fodder is their low nitrogen. Therefore, it is often difficult to provide sufficient nutrients, especially energy and protein for ruminants, which use these resources. Deficiency of nutrients in low quality forage also affects the supply of nutrients for growth of ruminal microorganisms and leads to a decrease in the ruminal digestion rate of these forages; this in turn reduces the feed intake and performance of the animal. Providing the sufficient nitrogen to ruminal microorganisms is important to increase carbohydrate digestibility and microbial protein production. Therefore, to achieve optimal performance, it is important to provide appropriate nitrogen supplements in areas where a significant portion of the ruminant diet consists of low-quality forage. One of the characteristics of ruminants is the ability to use non-protein nitrogen sources to synthesis of microbial protein in the rumen. Non-protein nitrogen, mainly urea, has been considered as a substitute for part of true protein due to its low price per unit of nitrogen compared to other true protein sources. The problem with using common urea is its rapid hydrolysis in the rumen and its conversion to ammonia. Most ruminal ammonia enters the bloodstream and causes destructive effects, from reduced feed intake and animal function to death from ammonia poisoning. The various slow-release urea compounds are made with the aim of continuously supplying nitrogen in the rumen. However, a part of the slow-release urea compounds may leave rumen without being converted to ammonia, reducing their performance for microbial protein production. Therefore, different sources of slow-release urea may have different effects. Processed or slow-release urea reduces ammonia poisoning and nitrogen wastage by reducing the rate of nitrogen release and improving feed costs. Therefore, the aim of this study was to investigate the effects of two sources of slow-release urea and compare them with diets without urea or containing common urea in the fattening lambs fed with low quality forage, to ultimately reduce production costs. Materials and Methods The present experiment was conducted at Agricultural Sciences and Natural Resources University of Khuzestan. Four experimental treatments were including 1- control treatment (without urea) and three treatments containing three different sources of non-protein nitrogen including 2- 1.8% slow-releasing urea-slowgen 3- 1.69% slow-release urea-optigene 4- 1.6% common urea. Twenty-four male Arabic lambs with (a mean weight of 25.65 ± 0.6 kg and 5± 1.0 months old were assigned to four experimental treatments with six replications. The nutrients digestibility was measured during seven days. The feed orts and feces were daily weighted and about 10% of them were kept in the plastic bags at -20˚C. At the end of this short period, the orts and feces samples were mixed and one representative sample obtained. The samples were oven-dried and grounded using 1 mm mesh screen. The chemical composition of rations, feed orts and feces, including dry matter, neutral detergent fiber, acid detergent fiber, organic matter, and crude protein were measured with standard methods. The dry matter intake, initial weight, every two weeks weight, final weight was recorded and feed conversion ratio and feed efficiency were calculated. Protozoa population, ammonia nitrogen, and pH of the rumen liquor were measured with standard procedure. The blood glucose, cholesterol, triglyceride, high density lipoprotein (HDL), low density lipoprotein (LDL), and BUN, were measured by spectrophotometric procedure. The data was analyzed using the GLM procedure of SAS (version 9.4). The differences among treatments were evaluated using Duncan’s adjustment (P < 0.05). Results and Discussion Compared to the control group, the use of slow-release urea sources had no effect on feed intake and digestibility of dry matter, NDF, ADF, and organic matter. Crude protein digestibility was highest in the control treatment and lowest in common urea treatment (P <0.05) and the control was not different from the slowgen treatment. Feed intake tended to increase in treatments containing urea (P = 0.07). Due to urea malnutrition, the use of urea sources may reduce feed intake, but in the present experiment this did not occur and even a slight increase was observed. This may be due to the presence of more molasses in urea-containing treatments; because molasses, due to its palatability, can increase the dry matter consumption of livestock. The growth performance of lambs in the whole period including final weight, average daily weight gain, total gain, feed conversion ratio, and feed efficiency were not affected by experimental treatments. The experimental treatments had no significant effect on the concentration of ruminal ammonia nitrogen, volatile fatty acids, protozoa population, pH, and blood parameters such as glucose and urea nitrogen. The diets containing common urea and slowgen had better benefits than control diets. In general, the findings of the present experiment showed that the results of treatments containing non-protein nitrogen sources were competitive with protein sources (control diet). In addition, there was no obvious difference between two sources of slow-release urea with each other, control, and common urea diets; but the slowgen worked better. Conclusion Finally, according to the results of the present experiment, related to the concentration of ruminal parameters in the present experiment, it can be concluded that the use of non-protein nitrogen compounds such as normal urea or slow-release as a substitute for conventional protein sources such as soybean meal did not have negative effects on ruminal fermentation. so, due to the lower price of urea compounds compared to soybean meal and other real nitrogen sources, although no difference was observed between slow-release urea sources and common urea; it can be stated that production productivity has also improved economically, therefore, the use of urea sources for fattening periods is recommended. |
- Alipour, D., A. Mohamed Saleem, H. Sanderson, T. Brand, L.V. Santos, M. Mahmoudi-Abyane, R. Marami, and T. A. McAllister. 2020. Effect of combinations of feed-grade urea and slow-release urea in a finishing beef diet on fermentation in an artificial rumen system, Translational Animal Science, 42: 839-847.
- Allen, M. S. 1997. Relationship between fermentation acid production in the rumen and the requirement for physically effective fiber. Journal of Dairy Science, 807: 1447‐
- Almora, E. A., G. B. Huntington, and J. C. Burns. 2012. Effects of supplemental urea sources and feeding frequency on ruminal fermentation, fiber digestion, and nitrogen balance in beef steers. Animal Feed Science and Technology, 171: 136-145.
- AOAC 2005. Official Methods of Analysis. 18th ed. AOAC international, Gaithersburg, MD.
- Babayemi, O. J., D. Demeyer, and V. Fievez. 2004. In vitro rumen fermentation of tropical browse seeds in relation to their content of secondary metabolites. Journal Animal Feed Science, 13: 31–34.
- Broderick, G., and J. H. Kang. 1980. Automated simultaneous determination of ammonia and total amino acids in ruminal fluid and in vitro Journal of Dairy Science, 63: 64-75.
- Chaji, M. 2019. Applied Animal Nutrition: Feeds and Feeding. 2th ed. Iran, Teharn: Norbaksh. Pp: 1-630. (In Persian)
- Cherdthong, A., M. Wanapat, and C. Wachirapakorn. 2011a. Effects of urea-calcium mixture in concentrate containing high cassava chip on intake, rumen fermentation and performance of lactation dairy cows fed on rice straw. Livestock Science, 136: 76−84.
- Cherdthong, A., M. Wanapat, and C. Wachirapakorn. 2011b. Influence of urea calcium mixture supplementation on ruminal fermentation characteristics of beef cattle fed on concentrates containing high levels of cassava chips and rice straw. Animal Feed Science and Technology, 163: 43–51.
- Dehority, B. A., and A. A. Odenyo. 2003. Influence of diet on the rumen protozoal fauna of indigenous African wild ruminants. Jornal of Eukaryot Microbiology, 503: 220‐
- Dönmez, N., M. A. Karslı, A. Çınar, T. Aksu, and E. Baytok. 2003. The effects of different silage additives on rumen protozoan number and volatile fatty acid concentration in sheep fed corn silage. Small Ruminant Research, 48: 227–231.
- Eynipour, P., M. Chaji, and M. Sari. 2019. Use of post-harvest common bean Phaseolus vulgaris residues in diet of lambs and its effect on finishing performance, rumen fermentation, protozoa population and meat characteristics. Journal of Animal Physiology and Animal Nutrient Berl, 1036: 1708‐1718.
- Galina, M. A., F. Perez-Gil, R. M. A. Ortiz, J. D. Hummel, and R. E. Ørskov. 2003. Effect of slow release urea supplementation on fattening of steers fed sugar cane tops Saccharum officinarum and maize Zea mays: ruminal fermentation, feed intake and digestibility. Livestock Prouction Science, 83: 1–11.
- Geron, L. J. V., S. C. De Aguiar, J. T. H. De Carvalho, G. D. Juffo, A. P. Da Silva, E. L. De Sousa Neto, K. S. M. Coelho, J. Garcia, L. C. Diniz, and E. J. H. De Paula. 2016. Effect of slow release in sheep feed on intake, nutrient digestibility, and ruminal parameters. Semina: Ciências Agrarias, Londrina, 37 4: 2793-2816.
- Hosoda, K., K. Kuramoto, B. Eruden, T. Nishida, and S. Shioya. 2006. The effect of three herbs as feed supplements on blood metabolites, hormones, antioxidant activity, IgG concentration, and ruminal fermentation in Holstein steers. Asian-australasian Journal of Animal Sciences, 191: 35-41.
- Huntington, G. B., D. L. Harmon, N. B. Kristensen, K. C. Hanson, and J. W. Spears. 2006. Effects of a slow-release urea source on absorption of ammonia and endogenous production of urea by cattle. Animal Feed Science and Technology, 1303: 225-241.
- Imani Rad, M., Y. Rouzbehan, and J. Rezaei. 2016. Effect of dietary replacement of alfalfa with urea-treated almond hulls on intake, growth, digestibility, microbial nitrogen, nitrogen retention, ruminal fermentation, and blood parameters in fattening lambs, Journal of Animal Science, 941: 349–358.
- Lizarazo, A. C., G. D. Mendoza, J. Kú, L. M. Melgoza, and M. Crosby. 2014. Effects of slowrelease urea and molasses on ruminal metabolism of lambs fed with low-quality tropical forage. Small Ruminant Research, 1161: 28-31.
- Mahmoudi-Abyane, M., D. Alipour, and H. Moghimi. 2020. Effects of different sources of nitrogen on performance, relative population of rumen microorganisms, ruminal fermentation and blood parameters in male feedlotting lambs. Animal, 147: 1438-1446.
- Malekkhahi, M., A. M. Tahmasbi, A. A. Naserian, M. Danesh Mesgaran, J. L. Kleen, and A. A. Parand. 2015. Effects of essential oils, yeast culture and malate on rumen fermentation, blood metabolites, growth performance and nutrient digestibility of Baluchi lambs fed high‐concentrate diets. Journal of Animal Physiology and Animal Nutrition, 992: 221-229.
- Mashayekhi, M. R., M. N. Erfani-majd, M. Sari, and M. Rezaei. 2020. Investigating the effects of slow-release urea and molasses on histomorphometric tissue of rumen and abomasum and rumen fermentation parameters of fattening lamb. Iranian Veterinary Journal, 161: 82-93. (in Persian).
- McDonald, P., R. A. Edwards, J. F. D. Greenhalgh, C. A. Morgan, L. A. Sinclair, and R. G. Wilkinson. 2010. Animal nutrition. 7 th edition. Lohgman Scientific and Technical, New York. Pp: 158-161.
- Mousavi Kia, S. A., A. Teimori Yansari, E. Dirandeh, and Gh. H. Irajian. 2019. Effects of different levels of replacement of slow-release urea with soybean meal on feed intake, blood parameters and performance of holstein lactating cows in early lactation. Journal of Veterinary Research, 744: 438-448. (in Persian).
- National Research Council. 2007. Nutrient requirements of small ruminants, sheep, goats, cervids, and new world camelids. Washington, DC: National Academy Press.
- Orskov, E. 1999. Supplement strategies for ruminants and management of feeding to maximize utilization of roughages. Preventive Veterinary Medicine, 382: 179-185.
- Ortiz, R. M. A., M. A. Galina, and M. M. A. Carmona. 2002. Effect of a slow non-protein nitrogen ruminal supplementation on improvement of cynodonnlemfuensis or Brachiariabrizanta utilization by Zebu steers. Livestock Production Science, 782: 125-131.
- Pond, W. G., D. C. Church, K. R. Pond, and P. A. Schoknecht. 2005. Micro- trace mineral elements. In: Basic Animal Nutrition and Feeding, 5th ed. Pp: 185–216.
- Puga, D. C., H. M. Galina, R. F. Pérez-Gil, G. L. Sanginés, B. A. Aguilera, and G. F. W. Haenlein. 2001. Effect of a controlled-release urea supplement on rumen fermentation in sheep fed a diet of sugar cane tops Saccharumofficinarum, corn stubble Zea mays and King grass Pennisetumpurpureum. Small Ruminant Research, 393: 269-276.
- Ravi Kanth Reddy, P., D. Srinivasa Kumar, E. Raghava Rao, C. Venkata Seshiah, K. Sateesh, and Y. Pradeep Kumar Reddy. 2019. Assessment of eco-sustainability vis-à-vis zoo-technical attributes of soybean meal SBM replacement with varying levels of coated urea in Nellore sheep Ovis aries. PLoS ONE, 148: e0220252.
- Saro, C., J. Mateo, S. Andrés, I. Mateos, M. J. Ranilla, S. López, A. Martín, and F. J. Giráldez. 2019. Replacing Soybean Meal with Urea in Diets for Heavy Fattening Lambs: Effects on Growth, Metabolic Profile and Meat Quality. Animals. 9: 974.
- Sevim, O., and A. G. Önol. 2019. Supplemental slow-release urea and non-structural carbohydrates: effect on digestibility and some rumen parameters of sheep and goats.The Journal of Animal and Plants Science, 291: 1-7.
- Talebian Masoudi, A., M.Moeini, M. Souri, H. Mansouri, and M. Abdoli. 2016. Manufacturing of a Slow-Release Non-Protein Nitrogen and Evaluation of Its Use in Ruminant Nutrition. Journal of Animal Production, 183: 399-411. (in Persian).
- Van Soest, P. J., J. B. Robertson, and B. A. Lewis. 1991. Methods for dietary fibre, neutral detergent fibre and non-starch polysaccharides in relation to animal nutrition. Journal of Dairy Science, 74: 3583–3597.
- Yixuan, Xu., Li. Zhipeng, Le. Moraes, J. Shen, Yu. Zhongtang, and Zhu. Weiyun. 2019. Effects of Incremental Urea Supplementation on Rumen Fermentation, Nutrient Digestion, Plasma Metabolites, and Growth Performance in Fattening Lambs. Animal, 9: 652.
- Zereu, G. H. 2016. Factors Affecting Feed Intake and Its regulation mechanisms in ruminants -A Review. International Journal of Livestock Research. 64: 19- 40.
- Zhang, F., S. K. Ji, Y. K. Sun, K. D. Deng, B. Wang, Y. Tu, N. F. Zhang, C. G. Jiang, S. Q. Wang, and Q. Y. Diao. 2017. Influence of dietary slow-release urea on growth performance, organ development and serum biochemical parameters of mutton sheep. Journal of Animal Physiology and Animal Nutrition, 1015: 964–973.
|