The effects of high levels of rumen degradable protein on rumen pH and histamine concentrations in dairy cows.

摘要: An experiment was conducted to test the hypothesis that supplementation of crude protein (CP) results in rumen acidosis and increased histamine concentrations dairy cows. Six ruminally fistulated, non-pregnant dry cows were fed three experimental rations a replicated 3 × Latin square design. The CP contents low-CP, high undegradable (high-RUP) degradable (high-RDP) 112, 259 266 g/kg matter (DM) respectively. 7.7 kg DM concentrates 2.7 rice straw. High levels RDP ration significantly ammonia, total volatile fatty acid (VFA) fluid. However, supplemental CP, whether or undegradable, did not affect pH Plasma urea nitrogen concentration higher both high-RDP high-RUP relation low-CP ration. rise ruminal physiologically non-relevant, most likely because affected by at installed level intake. Therefore, it can be concluded issue has yet been settled. Further research is warranted understand these relationships.