Furchtenicht J E, Broderick G A
J Dairy Sci. 1987 Jul;70(7):1404-10. doi: 10.3168/jds.S0022-0302(87)80162-5.
Chilling of whole rumen contents prior to preparation of strained rumen fluid enriched with particle-associated microorganisms resulted in rumen inoculum with the highest microbial dry weight, total bacterial counts, and degradation rates for casein and soybean meal. Strained rumen fluid, whole rumen contents blended with strained rumen fluid, chilled strained rumen fluid, and strained rumen fluid plus particle-associated microorganisms were lower in bacterial counts and microbial dry weight. Except for strained rumen fluid plus particle-associated microorganisms, protein degradation rates were also lower. Three ruminally cannulated cows were used in a 3 X 3 Latin square experiment to determine the effect of diet on rumen microbial numbers and protein degradation rates. Cows were fed the following diets ad libitum: 1) 100% alfalfa hay (20.7% crude protein); 2) 63% alfalfa hay and 37% corn-soybean meal concentrate (18.2% crude protein); and 3) 37% alfalfa hay and 63% corn-soybean meal concentrate (15.1% crude protein). Diet 3 yielded rumen contents with the highest concentration of microbial dry weight, total and viable bacterial counts, total protozoal counts, and fractional degradation rates for casein and bovine serum albumin. However, degradation rate per unit microbial dry matter was not altered by diet.
在制备富含颗粒相关微生物的过滤瘤胃液之前，对整个瘤胃内容物进行冷却，得到的瘤胃接种物具有最高的微生物干重、总细菌数以及酪蛋白和豆粕的降解率。过滤瘤胃液、与过滤瘤胃液混合的整个瘤胃内容物、冷却的过滤瘤胃液以及过滤瘤胃液加颗粒相关微生物的细菌数和微生物干重较低。除了过滤瘤胃液加颗粒相关微生物外，蛋白质降解率也较低。使用三头瘤胃插管奶牛进行3×3拉丁方实验，以确定日粮对瘤胃微生物数量和蛋白质降解率的影响。奶牛随意采食以下日粮：1）100%苜蓿干草（粗蛋白含量20.7%）；2）63%苜蓿干草和37%玉米-豆粕浓缩料（粗蛋白含量18.2%）；3）37%苜蓿干草和63%玉米-豆粕浓缩料（粗蛋白含量15.1%）。日粮3产生的瘤胃内容物中微生物干重、总细菌数和活菌数、总原生动物数以及酪蛋白和牛血清白蛋白的分级降解率最高。然而，单位微生物干物质的降解率不受日粮影响。
