Effects of urea supplementation on nutrient digestibility, nitrogen utilisation and rumen fermentation in sheep fed diets containing dates

Abstract

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authorsare permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/authorsrights a b s t r a c t Summary:The aim of the study was to determine the influence of increasing levels of urea (i.e., 0 (U0); 10 (U10); and 15 (U15) g kg -1 of concentrate) in sheep fed diets containing dates (local name: Azzawi), on nutrient intake and digestibility, N utilisation and ruminal fermentation. To maintain iso-nitrogenous and iso-metabolisable energy diets, the dates were added with increasing levels of urea. Sheep were fed a 400:600 (dry matter (DM) basis) concentrate:berseem hay (Trifolium alexandrinum) diet. Twelve Barki sheep (53.8 7 1.95 kg body weight) with three/diet were used in a randomised block design to determine digestibility and N balance, while four ruminally cannulated Barki sheep (56.6 7 2.15 kg body weight) were used in a 3 Â 3 Latin square design to determine rumen function. Experimental periods were 22 days with the first 15 days for adaptation. The calculated metabolisable energy (MJ kg -1 DM) and actual crude protein (CP; g kg -1 DM) contents were 12.17 and 156.1, 12.69 and 158.2 and 12.60 and 154.8, for the U0, U10 and U15 diets, respectively. Increased urea feeding increased (P o 0.05) digestibility of DM, organic matter (OM) and CP. Rumen ammonia N concentrations, allantoin in urine and the resultant microbial N supply increased linearly (P o 0.05), as did the total ruminal volatile fatty acid concentrations. Results suggest that urea supplementation to sheep diets containing dates improved DM, OM and CP digestibility and substantially increased rumen microbial growth as well as ruminal fermentation function. Crown

Effects of polymer coated slow-release urea on ruminal fermentation and nutrient total tract digestion of beef steers

“…Xin et al (2010) found similar results and suggested that higher acetate and lower butyrate concentrations in diets containing urea (FGU and SRU) resulted in lower conversion of acetate to butyrate in the rumen (Sharp et al, 1982;Sutton et al, 2003). Khattab et al (2013) observed higher acetate concentration when feeding urea, and an increase in microbial protein synthesis.…”

Improvement of nutritive value of cassava pulp and in vitro fermentation and microbial population by urea and molasses supplementation

“…However, there was no different effect among each level of U and M supplement. Rumen fermentation and digestibility were increased with the increasing levels of U supplement, which could be due to the increased rate of rumen microorganisms growth resulting from the presence of more available N in the form of ammonia from the hydrolysis of U (Boucher et al 2007;Khattab et al 2013;Kang et al 2015). In addition, Wanapat, Kang, Khejornsart et al (2013) reported that the supplementation of U and M could increase rumen degradability of whole-crop rice silage.…”

Effect of urea and molasses supplementation on quality of cassava top silage

“…The true digestibility was increased regardless M dose (M0.5 = M1 = M2), and the NDF digestibility was the highest in M2 group. The lack of U influence on in vitro true and NDF digestibilities is rather surprising as it is supposed that rumen fermentation and digestibility increases with the U supplementation due to the increased rumen microorganisms growth rate as there is more available N in the form of ammonia from the urea hydrolysis (Khattab et al, 2013;Kang et al, 2015). Moreover, found that supplementation of U and M could increase rumen degradability of whole crop rice silage.…”