摘要
The objectives of the trial were to compare the effects of supplementing rare earth elements (REE) lanthanum (La), cerium (Ce) and praseodymium (Pr) on rumen fermentation, nutrient digestion, methane (CH4) production, nitrogen (N) balance and plasma biochemical parameters in beef cattle. Four Simmental male cattle, aged 12 months, with initial average liveweight of 333 ± 9 kg and fitted with rumen cannulas, were fed with a basal ration composed of concentrate mixture and maize silage. Animals received a basal ration without adding REE (Control) or three treatments, i.e. supplementing LaCl3, CeCl3 or PrCl3 at 204 mg/kg DM to the basal ration, respectively, which were allocated in a 4 × 4 Latin square design. Each experimental period lasted 15 d, consisting of 12 d for pre-treatment and three subsequent days for sampling. Results showed that all tested levels of REE tended to increase neutral detergent fibre digestibility (p = 0.064) and tended to decrease rumen CH4 production (p = 0.056). Supplementing LaCl3 and CeCl3 decreased total N excretion and urinary N excretion, increased N retention (p < 0.05), tended to increase total urinary purine derivatives (PD) (p = 0.053) and microbial N flow (p = 0.095), whereas supplementing PrCl3 did not affect N retention, urinary PD and microbial N flow. No differences were found in the effects of nutrient digestibility, CH4 production and plasma biochemical parameters among LaCl3, CeCl3 and PrCl3. Further trials using graded levels of LaCl3, CeCl3 and PrCl3 in a wide range are needed to obtain more pronounced results for comparing effects of La, Ce and Pr on rumen fermentation and nutrient digestion in beef cattle.
摘要译文
该试验的目的是比较补充稀土元素（REE）镧（La），铈（Ce）和镨（Pr）对瘤胃发酵，营养物质消化，甲烷（CH 4）产生，氮（N）的影响。肉牛的平衡和血浆生化指标。将4只西门塔尔牛，年龄12个月，初始平均活重333±9公斤并装有瘤胃套管，饲喂由浓缩混合物和玉米青贮饲料组成的基础饲料。动物接受基础日粮而不添加REE（对照）或三种处理，即分别以204mg / kg DM补充LaCl 3，CeCl 3或PrCl 3至基础日粮，其以4×4拉丁方设计分配。每个实验期持续15天，包括12天用于预处理和随后三天用于取样。结果显示，所有测试的REE水平倾向于增加中性洗涤剂纤维的消化率（p = 0.064）并且倾向于降低瘤胃CH 4的产生（p = 0.056）。补充LaCl 3和CeCl 3可降低总N排泄和尿N排泄，增加N保留（p <0.05），倾向于增加总尿嘌呤衍生物（PD）（p = 0.053）和微生物N流量（p = 0.095），而补充PrCl 3不影响N保留，尿PD和微生物N流量。 LaCl 3，CeCl 3和PrCl 3对营养物质消化率，CH 4产生和血浆生化指标的影响没有差异。为了比较La，Ce和Pr对肉牛瘤胃发酵和营养物质消化的影响，需要在较宽范围内使用分级水平的LaCl 3，CeCl 3和PrCl 3进行进一步的试验。
Shixin Lin[1];Chen Wei[1];Guangyong Zhao[2];Tingting Zhang[1];Kai Yang[1]. Comparison of the effects of lanthanum, cerium and praseodymium on rumen fermentation, nutrient digestion and plasma biochemical parameters in beef cattle[J]. Archiv für Tierernaehrung, 2015,69(1): 46-56