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刘又铭房鑫农可懿周璐彤喻赫石庆珍于江辉张海文 《饲料研究》2021,44(18):133-137
维生素D_(3)(VD_(3))作为饲料中常用的维生素添加剂,在畜禽生产中发挥着重要作用。文章综述近年来VD_(3)在生物先天免疫功能中扮演的角色,介绍VD_(3)在体内的代谢过程、抗氧化功能以及对免疫细胞的作用,进一步探讨这些功能是否有应用于畜牧领域的潜力,为VD_(3)在畜禽饲料中的合理应用提供参考。 相似文献
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维生素D3是畜禽所必需的营养素。越来越多的研究表明,维生素D3除具有经典的调节钙磷代谢和促进骨骼生长的作用外,还具有其它更为广泛的骨外生物学功能,如调节免疫、提高繁殖力、改善肉质、抗感染、抗肿瘤、防治疗自身免疫性疾病等。 相似文献
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维生素(Vitamin)是动物机体的营养物质,为动物所必需。但维生素在动物体内不能合成或者合成量少,不能满足动物的需要,因此,必须摄食饲料以满足生长发育的需要。维生素按溶解性的不同分为水溶性维生素和脂溶性维生素两大类。水溶性维生素主要包括维生素 B 族及维生素 C,维生素 B 族是构成动物体内辅酶的主要成分;脂溶性维生素主要包括维生素 A、D、E、K 四种,脂溶性维生素虽然不是构成辅酶的成分,但它们在动物体内具有很重要的生理、生化机能。本文就维生素 D 的生物学功能及合理使用作些介绍。 相似文献
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关于维生素D生物学效价的评定方法主要分为生物学方法和化学方法,然而至今对其没有统一的结论。研究结果大部分显示维生素D3的效价高于或等于维生素D2的效价,且维生素D3及其代谢产物效价的对比大致为维生素D3≤24,25-二羟基维生素D3[24,25-(OH)2D3]=25,26-二羟基维生素D3[25,26-(OH)2D3]≤25-羟基维生素D3[25-(OH)D3]≤1,25-二羟基维生素D3[1,25-(OH)2D3]。影响维生素D生物学效价的因素有多种,其内在因素主要包括关键酶的活性及其反馈调节机制、活性维生素D的结构与维生素D转运蛋白及维生素D受体的亲和性差异等;外在因素主要有试验动物、评价指标及评价方法、光照、维生素D载体等。本文主要从维生素D生物学效价的评定方法、内在和外在的影响因素方面进行综述,为相关研究提供一定的参考依据。 相似文献
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人参皂甙的生物学效应研究进展 总被引:3,自引:0,他引:3
人参皂甙在免疫调节、诱导细胞凋亡、抗组织损伤、抗肿瘤、抗氧化、治疗糖尿病等方面具有特殊的作用,同时也将作为一种绿色饲料添加剂应用于动物生产。因此,对人参皂甙的生物学效应的研究有重要意义。 相似文献
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试验选取1日龄健康、体重相近的金定蛋雏鸭180只,随机分为5个处理组,每个处理6个重复,每个重复6只试鸭。采用玉米-豆粕型基础饲粮,Ⅰ组试验鸭饲喂基础饲粮,Ⅱ~Ⅴ组分别饲喂在基础饲粮中添加110、220、550、1000 IU/kg维生素D的试验饲粮,试验期4周。旨在研究不同维生素D添加水平对1~28日龄蛋雏鸭生长性能及免疫功能的影响,以探讨维生素D的适宜添加量。结果表明,添加550 IU/kg维生素D能显著提高蛋雏鸭平均日增重、降低料重比(P<0.05),显著提高IgA、IgG、T3、T4含量(P<0.05),并显著降低Cort含量(P<0.05)。由此可见,在玉米-豆粕型基础饲粮中添加适量的维生素D可提高蛋雏鸭生长性能及免疫功能。通过二次回归模型分析,估测蛋雏鸭日粮中维生素D的适宜添加量为523.1~560.6 IU/kg。 相似文献
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Effects of growth hormone administration on vitamin D metabolism and vitamin D receptors in the pig 总被引:1,自引:1,他引:0
Twelve 36-kg pigs were given either 100 micrograms/kg porcine pituitary growth hormone (pGH) or placebo injections daily for 33 days. Serum was obtained weekly for analysis of minerals and vitamin D metabolites. On day 34, the pigs were sacrificed and renal and duodenal tissue were obtained for analysis of vitamin D receptor content (VDR). Animals treated with pGH grew faster and had a higher rate of bone accretion than did control animals. Serum concentrations of 1,25-dihydroxyvitamin D (1,25-(OH)2D) were significantly higher in pGH-treated pigs than in control pigs at all time points following initiation of treatment, with the greatest difference observed at day 28 (42.4 +/- 4.9 pg/ml in controls vs. 65.4 +/- 4.7 pg/ml in pGH-treated pigs). Serum 24,25-dihydroxy-vitamin D tended to be lower in pGH-treated pigs than in control pigs, being significantly lower on day 21 of the experiment (3.22 +/- .52 vs. 6.73 +/- 1.22 ng/ml, respectively). Serum concentrations of 25-hydroxyvitamin D and calcium were unaffected by pGH treatment. Kidneys of control pigs contained significantly more unoccupied vitamin D receptors than did kidneys from pGH-treated pigs (73.3 +/- 4.3 vs. 58.3 +/- 4.1 fmoles/mg protein). Duodenal tissue unoccupied vitamin D receptor content was similar in both pGH-treated (245 +/- 17.9 fmoles/mg protein) and control (263 +/- 21.8 fmoles/mg protein) pigs. Duodenal occupied vitamin D receptor concentration was similar in both pGH-treated (6.8 +/- .75 fmoles/mg protein) and control pigs (5.32 +/- .77 fmoles/mg protein).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Montgomery JL Blanton JR Horst RL Galyean ML Morrow KJ Wester DB Miller MF 《Journal of animal science》2004,82(7):2043-2049
Feedlot steers (n = 36) from three biological types (Bos indicus, Bos taurus-Continental, and Bos taurus-English) were used to determine the Ca, P, and vitamin D3 status of feedlot cattle. The USDA yield and quality grade traits were measured at slaughter, and the concentrations of vitamin D3 (VITD) and the metabolites 25-hydroxyvitamin D3 (25-OH D) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2 D) were determined in LM, liver, kidney, and plasma. Plasma and muscle Ca and P concentrations also were determined. Biological type of cattle affected a number of carcass traits. Carcasses from Bos taurus-English cattle had more marbling, resulting in higher quality grades (P < 0.05). Carcasses from Bos taurus-Continental cattle had lower calculated yield grades (P < 0.05) than did carcasses from cattle in the other biological types. In general, differences in carcass traits resulting from biological type were consistent with other reports. Plasma and LM Ca and P concentrations were not affected (P = 0.06) by biological type of cattle, indicating that Ca and P homeostasis is a conserved trait across the different types of cattle. Plasma VITD and 25-OH D concentrations were not affected (P = 0.41) by biological type, whereas plasma 1,25-(OH)2 D concentration was lower (P < 0.05) in Bos taurus-English cattle than in Bos taurus-Continental and Bos indicus cattle. Liver VITD and 25-OH D were not affected by biological type (P = 0.76), but liver 1,25-(OH)2 D concentration was greater (P < 0.05) in Bos indicus cattle than in Bos taurus-Continental cattle. Kidney vitamin D metabolite concentrations were not affected by biological type of cattle (P = 0.21). Muscle VITD concentration was greater (P < 0.05) in Bos taurus-English cattle than in the other two biological types, and muscle 25-OH D concentrations were greater (P < 0.05) in Bos taurus-English cattle than in Bos indicus cattle. Muscle 1,25-(OH)2 D concentration was less (P < 0.05) in the Bos taurus-Continental cattle than in the other two biological types. Cooking eliminated vitamin D metabolite differences among the biological types. Our results suggest that Bos indicus cattle had greater 1,25-(OH)2 D (the biologically active form) in tissues, and greater 1,25-(OH)2 D plasma concentrations than Bos taurus cattle. Thus, the need for VITD supplementation and optimal levels of Ca and P in feedlot diets might differ between Bos indicus and Bos taurus cattle. 相似文献