title: Rumen bacterial urease requirement for nickel.
abstract: Lambs were fed a basal purified diet low in nickel (60 ppb) or the basal diet supplemented with 5 ppm of nickel to determine if rumen bacterial urease was a nickel-requiring enzyme. Two collection periods with lambs fed a diet in which all the nitrogen was supplied as preformed protein (casein) indicated that ruminal urease activity was much lower in lambs fed the low nickel diet. When 1% urea was added to the basal diet, urease activity increased slightly with both treatments; however, bacterial urease activity was still much higher in the lambs receiving 5 ppm of nickel. Ruminal volatile fatty acids were not influenced by dietary nickel. Ruminal urease requires nickel for maximal activity.
mesh_terms: D000641:Ammonia / Q000378:metabolism; D000818:Animals; D001419:Bacteria / Q000201:enzymology*; D002364:Caseins / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000378:metabolism; D008297:Male; D009532:Nickel / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism / Q000382:microbiology*; D012756:Sheep / Q000378:metabolism*; D014508:Urea / Q000378:metabolism; D014510:Urease / Q000378:metabolism*
chemical_list: D002364:Caseins; D005232:Fatty Acids, Volatile; D000641:Ammonia; D009532:Nickel; D014508:Urea; D014510:Urease