Rivera J D, Bachman S E, Hubbert M E, Branine M E, Horst R L, Williams S N, Galyean M L
Department of Animal and Food Sciences, Box 42141, Texas Tech University, Lubbock, 79409-2141, USA.
J Dairy Sci. 2005 Apr;88(4):1364-9. doi: 10.3168/jds.S0022-0302(05)72803-4.
Sixteen crossbred (British x Continental; average un-shrunk body weight = 507.9 kg; SD = 45.6 kg) beef heifers fed a steam-flaked corn-based finishing diet with melengestrol acetate (0.4 mg/heifer daily) included to suppress estrus were used in a completely random design to evaluate the efficacy of buccal administration of 0, 10, 100, or 1000 mg of 25-hydroxyvitamin D3, (25-OH D3). Serum Ca, P, Mg, 25-OH D3, 1,25-dihydroxyvitamin D [1,25-(OH)2 D3], albumin, and protein were measured 24 h before dosing (-24 h), at dosing (0 h), and 6 and 24 h after dosing, after which the cattle were slaughtered at a commercial facility. Samples of kidneys, liver, longissimus lumborum, and triceps brachii were collected and evaluated for concentrations of 1,25-(OH)2 D3. With -24 and 0 h as baseline covariates, a significant time x treatment interaction was observed for serum 25-OH D3 and Ca concentrations, but not for serum 1,25-(OH)2 D3. Supplemental 25-OH D3 doses of 100 and 1000 mg significantly increased serum 25-OH D3 at 24 h after dosing, 1,25-(OH)2 D3 at 6 and 24 h after dosing, and serum Ca at 24 h after dosing. Similarly, buccal dosing of 1000 mg of supplemental 25-OH D3 significantly increased (approximately 2- to 3-fold) concentrations of 1,25-(OH)2 D3 in the kidney, liver, and longissimus lumborum relative to the other 3 treatments but not in triceps brachii. Serum albumin, protein, P, and Mg were not affected by treatment. Based on these results, buccal administration of 100 and 1000 mg 25-OH D3 increased vitamin D3 metabolites in serum and tissues, and it should be an effective method of delivering the vitamin.
选用16头杂交（英国品种×欧洲大陆品种；平均未缩水体重=507.9千克；标准差=45.6千克）肉用小母牛，给它们饲喂含醋酸甲地孕酮（每天0.4毫克/小母牛）以抑制发情的蒸汽压片玉米育肥日粮，采用完全随机设计来评估经口给予0、10、100或1000毫克25-羟基维生素D3（25-OH D3）的效果。在给药前24小时（-24小时）、给药时（0小时）以及给药后6小时和24小时测定血清钙、磷、镁、25-OH D3、1,25-二羟基维生素D[1,25-(OH)2 D3]、白蛋白和蛋白质，之后在商业屠宰场宰杀这些牛。采集肾脏、肝脏、腰大肌和肱三头肌样本并评估其中1,25-(OH)2 D3的浓度。以-24小时和0小时作为基线协变量，观察到血清25-OH D3和钙浓度存在显著的时间×处理交互作用，但血清1,25-(OH)2 D3不存在这种交互作用。补充100毫克和1000毫克25-OH D3剂量显著提高了给药后24小时的血清25-OH D3、给药后6小时和24小时的血清1,25-(OH)2 D3以及给药后24小时的血清钙。同样，经口给予1000毫克补充25-OH D3相对于其他3种处理显著提高了（约2至3倍）肾脏、肝脏和腰大肌中1,25-(OH)2 D3的浓度，但肱三头肌中未提高。血清白蛋白、蛋白质、磷和镁不受处理影响。基于这些结果，经口给予100毫克和1000毫克25-OH D3可提高血清和组织中的维生素D3代谢物水平，应该是一种有效的维生素给药方法。
