02809naa a2200277 a 450000100080000000500110000800800410001902400310006010000220009124501260011326000090023952019970024865000160224565000120226165000240227365000110229765300120230865300250232070000150234570000220236070000170238270000260239970000190242570000180244477300690246219235642023-02-22       2012    bl uuuu     u00u1 u    #d7 a10.2527/jas.2011-42092DOI1 aHULSHOF, R. B. A.  aDietary nitrate supplementation reduces methane emission in beef cattle fed sugarcane-based diets.h[electronic resource]  c2012  aThe objective of this study was to determine the effect of dietary nitrate on methane emission and rumen fermentation parameters in Nellore x Guzera (Bos indicus) beef cattle fed a sugarcane based diet. The experiment was conducted with 16 steers weighing 283 ± 49 kg (mean ± SD), six rumen cannulated and ten intact, in a cross-over design. The animals were blocked according to body weight and presence or absence of rumen cannula and randomly allocated to either the nitrate diet (22 g nitrate/ kg DM) or the control diet made isonitrogenous by the addition of urea. The diets consisted of freshly chopped sugarcane and concentrate (60:40 on DM basis), fed as a mixed ration. A 16-d adaptation period was used to allow the rumen microbes to adapt to dietary nitrate. Methane emission was measured using the sulfur hexafluoride tracer technique. Dry matter intake (P = 0.09) tended to be lower when nitrate was present in the diet compared to the control, 6.60 and 7.05 kg DMI, respectively. The daily methane production was reduced (P &lt 0.01) by 32% when steers were fed the nitrate diet (85 g/d) compared with the urea diet (125 g/d). Methane emission per kg DMI was 27% lower (P &lt 0.01) on the nitrate diet (13.3 g methane/kg DMI) than on the control diet (18.2 g methane/kg DMI). Methane losses as a fraction of gross energy intake (GEI) were lower (P &lt 0.01) on the nitrate diet (4.2% of GEI) than on the control diet (5.9% of GEI). Nitrate mitigated enteric methane production by 87% of the theoretical potential. The rumen fluid ammonia-nitrogen (NH3-N) concentration was significantly greater (P &lt 0.05) for the nitrate diet. The total concentration of VFA was not affected by nitrate in the diet, whilst the proportion of acetic acid tended to be greater (P = 0.09), propionic acid lower (P = 0.06) and acetate/propionate ratio tended to be greater (P = 0.06) for the nitrate diet. Dietary nitrate reduced enteric methane emission in beef cattle fed sugarcane based diet.  abeef cattle  amethane  asulfur hexafluoride  aRúmen  aNitrate  aParameters sugarcane1 aBERNDT, A.1 aGERRITS, W. J. J.1 aDIJKSTRA, J.1 aZIJDERVELD, S. M. van1 aNEWBOLD, J. R.1 aPERDOK, H. B.  tJournal of Animal Sciencegv. 90, n. 7, p. 2317-2323, jul. 2012.