Ivan M
Can J Physiol Pharmacol. 1981 Jan;59(1):76-83. doi: 10.1139/y81-013.
Twelve sheep, each prepared with a rumen fistula, were divided into three groups of four and fed three dietary levels of manganese (22,300, and 3000 micrograms/g dry matter) for 11 weeks. The sheep were then dosed with radioactive manganese and samples of rumen contents were taken via the rumen fistula at 1, 7, and 13 h after dosing. The sheep were immediately killed after the last sampling and total rumen contents were mixed and sampled. Rumen fluid was separated frm all samples and fractionated by centrifugation into protozoa plus plant particles, bacteria, and cell-free fraction. The bacterial cells were disrupted and fractionated into cell walls and cytoplasm. The cytoplasmic protein was precipitated with trichloroacetic acid. Although the centration of radiomanganese in rumen fluid decreased with time after dosing from 14.4--17.8 to 6.1--9.3% of dose/L the protozoal and bacterial uptakes of radiomanganese were not significantly different and ranged from 26.5 to 40.6% and 18.9 to 31.7% of total in the rumen fluid, respectively. There was also no effect of dietary concentration of manganese on the uptake and distribution of radiomanganese in the rumen fluid fractions. However, on the average more radiomanganese was found in the bacterial cell walls (48.1--75.3% of total in bacteria) and less in the cytoplasm (51.9--24.7% of total in bacteria) with increasing dietary manganese. Very little radioactivity was found in the trichloroacetic acid precipitated cytoplasm (1.79--0.78% of total in cytoplasm). concentrations of manganese in the bacteria and bacterial cell walls were higher than, and closely related with, those in the diet. Specific activities of radiomanganese decreased in all fractions with increasing dietary manganese. Approximately 15--17% of the total radiomanganese in the rumen contents at 13 h after dosing was found in the protozoal fraction and 10--15% was found in the bacterial fraction; only approximately 21% of the radiomanganese remained in cell-free fraction of the rumen fluid in each dietary treatment.
12只均安装有瘤胃瘘管的绵羊被分成3组，每组4只，分别饲喂3种不同锰含量水平（22、300和3000微克/克干物质）的日粮，为期11周。然后给绵羊注射放射性锰，并在注射后1小时、7小时和13小时通过瘤胃瘘管采集瘤胃内容物样本。在最后一次采样后立即宰杀绵羊，将瘤胃全部内容物混合并采样。从所有样本中分离出瘤胃液，通过离心将其分为原生动物加植物颗粒、细菌和无细胞部分。将细菌细胞破碎并分为细胞壁和细胞质。用三氯乙酸沉淀细胞质蛋白。尽管给药后瘤胃液中放射性锰的浓度随时间下降，从剂量的14.4% - 17.8%降至6.1% - 9.3%/升，但原生动物和细菌对放射性锰的摄取没有显著差异，分别占瘤胃液总量的26.5%至40.6%和18.9%至31.7%。日粮中锰的浓度对瘤胃液各部分中放射性锰的摄取和分布也没有影响。然而，随着日粮中锰含量的增加，平均而言，细菌细胞壁中发现的放射性锰更多（占细菌总量的48.1% - 75.3%），而细胞质中则较少（占细菌总量的51.9% - 24.7%）。在三氯乙酸沉淀的细胞质中发现的放射性极少（占细胞质总量的1.79% - 0.78%）。细菌和细菌细胞壁中的锰浓度高于日粮中的锰浓度，且与日粮中的锰浓度密切相关。随着日粮中锰含量的增加，所有部分中放射性锰的比活度均降低。给药后13小时，瘤胃内容物中约15% - 17%的总放射性锰存在于原生动物部分，10% - 15%存在于细菌部分；在每种日粮处理中，只有约21%的放射性锰保留在瘤胃液的无细胞部分。
