TY  - JOUR
T1  - Response of Ruminal Fermentation, Methane Production and Dry Matter Digestibility 
  to Microbial Source and Nitrate Addition Level in an<I> in vitro </I>Incubation 
  with Rumen Microbes Obtained from Wethers
AU - Meng, Qingxiang AU - Zhou, Zhenming AU - Ren, Liping AU - Hou, Xianzhi AU - Shi, Caixia 
JO  - Journal of Animal and Veterinary Advances
VL  - 11
IS  - 18
SP  - 3334
EP  - 3341
PY  - 2012
DA  - 2001/08/19
SN  - 1680-5593
DO  - javaa.2012.3334.3341
UR  - https://makhillpublications.co/view-article.php?doi=javaa.2012.3334.3341
KW  - rumen fermentation
KW  -potassium nitrate
KW  -nitrate diet
KW  -Urea diet
KW  -methane
KW  -digestibility in vitro
AB  - Researchers evaluated the response of ruminal fermentation, methane production and dry matter digestibility to microbial source and nitrate addition level in an <I>in vitro</I> incubation using rumen microbes from wethers fed a diet with or without supplementary nitrate. Potassium nitrate was added to the fermentation substrates <I>in vitro</I> to form three different levels of nitrate-N (4, 8 and 16 g kg<SUP>-1</SUP> DM). Compared with microbial source from urea diet-fed wethers, ruminal microbes from nitrate diet-fed animals had increased total gas production, CH<SUB>4</SUB> and CO<SUB>2</SUB> production, acetate molar proportion and DM digestibility but had decreased ruminal nitrite accumulation, NH<SUB>3</SUB>-N concentration, total VFA production and molar proportion of propionate and butyrate. There was no effect of interaction between microbial source and nitrate-N addition level on ruminal fermentation characteristics, methane production and dry matter digestibility. Along with the increase of nitrate- N addition level, production of CH<SUB>4</SUB> and CO<SUB>2</SUB> and molar proportion of propionate were reduced whereas residual concentrations of both nitrate and nitrite in the incubation medium were increased. Nevertheless, total VFA production and DM digestibility was not affected by nitrate-N addition level <I>in vitro</I>. In conclusion although, nitrate addition has ability to inhibit ruminal methane production, the inhibition ability would gradually vanish after the microbes acclimate to the nitrate diet. The results imply that nitrate has a potential value as a dietary nitrogen supplement used by ruminant animals.
ER  -