Michnová E, Boda K, Tomás J, Havassy I
Physiol Bohemoslov. 1979;28(6):545-50.
Urease activity, expressed as mg N-NH3/g dry weight per 30 min at 25 degrees C, was determined in the various parts of the sheep, chicken and pig digestive apparatus. The results were as follows. Sheep: contents--rumen 1.25"/-0.09, reticulum 0.78+/-0.02, omasum 0.44+/-0.02, abomasum 0.002+/-0.001, duodenum 0.003+/-0.001, jejunum 0.18+/-0.03, ileum 0.42+/-0.03, caecum 1.34+/-0.11, colon 0.76+/-0.08, walls-rumen 0.88+/-0.16, reticulum 0.38+/-0.04, omasum 0.11+/-0.02, abomasum 0.01+/-0.002, ileum 0.092+/-0.01, caecum 0.14+/-0.03, colon 0.16+/-0.02. Chicken: contents--jejunum 0.028+/-0.009, ileum 0.043+/-0.013, caecum 0.17+/-0.03, colon and cloaca 0.04+/-0.013. Pigs: contents--jejunum 0.02+/-0.01, ileum 0.14+/-0.08, caecum 0.62+-0.12, colon 0.43+/-0.06. No urease activity was found in the walls of the digestive apparatus or the contents of the duodenum in chickens, or in the walls of the stomach and intestine and the contents of the duodenum in pigs. The results show that urease activity in the digestive apparatus of pigs and poultry is lower than in sheep. Inadequate urease activity in the digestive apparatus explains why chickens and pigs are significantly less capable than ruminants of utilizing urea nitrogen as a substitute for some of the protein in the diet.
在绵羊、鸡和猪消化系统的各个部位测定了脲酶活性，以25℃下每30分钟每克干重毫克氮 - 氨表示。结果如下。绵羊：内容物——瘤胃1.25±0.09，网胃0.78±0.02，瓣胃0.44±0.02，皱胃0.002±0.001，十二指肠0.003±0.001，空肠0.18±0.03，回肠0.42±0.03，盲肠1.34±0.11，结肠0.76±0.08；壁——瘤胃0.88±0.16，网胃0.38±0.04，瓣胃0.11±0.02，皱胃0.01±0.002，回肠0.092±0.01，盲肠0.14±0.03，结肠0.16±0.02。鸡：内容物——空肠0.028±0.009，回肠0.043±0.013，盲肠0.17±0.03，结肠和泄殖腔0.04±0.013。猪：内容物——空肠0.02±0.01，回肠0.14±0.08，盲肠0.62±0.12，结肠0.43±0.06。在鸡的消化系统壁或十二指肠内容物中未发现脲酶活性，在猪的胃和肠壁以及十二指肠内容物中也未发现脲酶活性。结果表明，猪和家禽消化系统中的脲酶活性低于绵羊。消化系统中脲酶活性不足解释了为什么鸡和猪利用尿素氮替代日粮中部分蛋白质的能力明显低于反刍动物。
