Ivan M, Grieve C M
J Dairy Sci. 1976 Oct;59(10):1764-8. doi: 10.3168/jds.s0022-0302(76)84435-9.
Sixteen Holstein bull calves were fed a high-concentrate ratio supplemented with zinc, copper, and manganese, alone or in combination, for 10 wk. After 6 days of preliminary feeding of chromic oxide, fecal grab-samples were collected for 6 days. Calves were slaughtered, and samples of the contents of the reticulo-rumen, omasum, abomasum, small intestine, cecum, and large intestine were analyzed for chromic oxide, copper, and manganese. Absorption along the gastrointestinal tract, measured by comparison of one segment with the previous segment, indicated net secretion of copper in the abomasum but net absorption from the rest of the tract. The exception was that net secretion into the reticulo-rumen was associated with low dietary copper. Net secretion of manganese was mainly in the small intestine and cecum in all treatments. A higher proportion of copper apparently was absorbed when this mineral was supplemented in the ration. However, absorption of manganese was decreased slightly when manganese was supplemented in the ration. Reabsorption of manganese in the large intestine was probably greater than that of copper.
16头荷斯坦公牛犊单独或组合补饲锌、铜和锰，高精料比日粮，为期10周。在以氧化铬预饲6天后，采集6天的粪便随机样本。屠宰犊牛，并分析瘤胃、瓣胃、皱胃、小肠、盲肠和大肠内容物中的氧化铬、铜和锰。通过比较一段消化道与前一段消化道来测量沿胃肠道的吸收情况，结果表明皱胃中有铜的净分泌，但消化道其他部位有铜的净吸收。例外情况是，瘤胃中的净分泌与低日粮铜有关。在所有处理中，锰的净分泌主要发生在小肠和盲肠。当日粮中添加这种矿物质时，显然有更高比例的铜被吸收。然而，当日粮中添加锰时，锰的吸收略有下降。大肠中锰的重吸收可能大于铜。
