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2007～2008年国际反刍动物营养研究进展
Ⅷ.维生素营养 总被引：1，自引：1，他引：0
作者综述了2007～2008年脂溶性和水溶性维生素在反刍动物上的研究进展。VA可提高反刍动物的免疫功能,影响牛肉品质和反刍动物脂肪组织的发育,不同来源的VA的生物学活性有差异;VD3可提高奶牛免疫力,VD3的吸收率优于VD2,提高血清中25(OH)D3的浓度,影响牛肉品质;VE可提高产奶量,降低乳房炎、胎衣不下等疾病的发病率,刺激生殖器官发育,改善牛肉品质。烟酸不仅能缓解热应激对奶牛生产性能的影响,还能减少血浆中游离脂肪酸的浓度,从而减少脂肪肝的发生。VB12能促进葡萄糖的代谢,提高初生羔羊的生命力。胆碱能提高奶牛的生产性能,增加产奶量、乳蛋白和乳脂,并影响奶牛的繁殖性能。经过包被的VC有较好的过瘤胃能力,能更多的在肠道被吸收,促进奶牛对VC吸收。 相似文献
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维生素D除具有调控钙、磷代谢和骨稳态等作用之外,在其他组织中也发挥多种活性作用,如调控免疫系统和调节细胞增殖与分化等方面的新作用。维生素D受体（VDR）除了在其传统组织如骨、肠道和肾脏中发现以外,还在众多组织中被发现。此外,这些组织中亦含有酶CYP2781,其可使维生素D循环形式25-OH—D3转化生成1,25（OH）2D3。1,25（OH）2D3在非肾组织中的代谢与肾脏不同,且VDR介导的转录活性调控作用也是细胞特异性的,因而维生素D的新作用具有细胞特异性,这为维生素D及其类似物提供了许多新的,临床应用依据,但其非传统作用也受到维生素D传统作用的限制,如高血钙和高尿钙。 相似文献
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旨在研究1,25(OH)2D3是否通过VDR途径调节山羊附睾头上皮细胞β防御素基因表达。本试验选取3只6月龄太行黑山羊，分别采集附睾头组织。采用差速贴壁法分离山羊附睾头上皮细胞，用细胞免疫荧光鉴定上皮细胞纯度。添加100 nmol·L-1 1,25(OH)2D3处理附睾头上皮细胞以及筛选出敲除效率最高的pCas9/gRNA1质粒载体进行细胞转染，同时设置阴性对照组和空白对照组，每组3个重复孔。附睾头上皮细胞经1,25(OH)2D3处理以及VDR基因敲除后，分别用qRT-PCR检测VDR和17种β防御素基因的表达，用Western blot检测VDR蛋白和3种β防御素蛋白的表达。结果表明，1,25(OH)2D3能极显著提高VDR、gBD124、gBD126和gBD104a的mRNA和蛋白表达(P<0.01),同时极显著提高gBD104、gBD109tr1、gBD109tr2、gBD113... 相似文献
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维生素D的生物学功能1.一般作用模式现已确认,VD在靶组织特别是1,25—(OH)_2D_3在肠和骨骼中是通过类似于类固醇激素的作用对许多生物学活动进行调节。这些功能包括细胞生长、分化和免疫功能,还有与矿物质代谢有关的许多靶组织的活动(Herdt 等,1991)。1,25—(OH)_2D_3在雏鸡肠道内可刺激 mRNA 编码 VD 依赖性钙结合蛋白(CaBP)(Christak 等,1980)。此外,还发现其他 VD 依赖性蛋白质,如在肠道作为线粒体外膜一部分的分子量为39000～42000的一种蛋白质(Hobden 等,1980)、一种精胺结合蛋白(Mezzetti 等,1981)、鸟氨酸脱羧酶(Shinki 等,1981)和一种分子量为67000的 相似文献
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维生素D的应用形式有维生素D2、D3、25-OHD3和1,25-(OH)2-D3几种形式,其中D3为最常用的形式。25-OH-D3是维生素D 3在肝脏中转化后的一种形式,随后又在肾脏中转化为最终活性形式1,25-(OH)2-D3。作为维生素D3和1,25-(OH)2-D 3的中间产物,25-OH-D3在动物体内活性比维生素D3更高,吸收更有效。1维生素D的生理功能及其在动物体内的代谢维生素D通过类似于类固醇激素的作用机理对动物的许多生物学功能进行调节,主要在以下几个方面发挥作用:1)维持动物体内钙、磷稳恒,保持骨骼的正常生长发育,防止钙缺乏症,如软骨病、佝偻病等,这是维生素D最重要的生理功能。2)提高肉品质。维生素D可刺激机体骨钙的动员,并且促进扩流入骨骼肌细胞中,使钙激酶被激活,从而促进肉的嫩化。 相似文献
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《中国兽医学报》2020,(10)
旨在探明1,25(OH)_2D3对猪伪狂犬病病毒(pseudorabies virus,PRV)诱导小鼠流产的影响。采用颈背部皮下注射不同剂量PRV建立PRV诱导小鼠流产模型;通过实时荧光定量PCR检测不同剂量1,25(OH)_2D3预处理组和生理盐水预处理组小鼠卵巢和子宫内VDR mRNA的水平及PRV量;利用组织学病理切片技术观察PRV引起的1,25(OH)_2D3预处理组和生理盐水处理组小鼠子宫和卵巢的病理变化。结果显示,成功建立了小鼠流产模型,确定了引起小鼠流产的PRV最佳接种剂量为0.35 mL 1 000 TCID_(50) PRV;用300μg/kg 1,25(OH)_2D3预处理,小鼠VDR表达水平最高,能有效抑制病毒的增殖,对PRV感染小鼠流产的抑制作用最强。组织病理学检查发现,相较于生理盐水预处理的PRV感染组,1,25(OH)_2D3预处理组小鼠卵泡腔内颗粒细胞增多、红细胞量减少;子宫腔内红细胞数量减少或消失,子宫内膜皱褶增多。结果表明,1,25(OH)_2D3能有效抑制PRV增殖,降低PRV诱导的小鼠流产。 相似文献
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《国外畜牧学(猪与禽)》2021,41(4)
钙储备充足是保证蛋鸡骨骼质量和蛋壳质量的关键。1,25(OH)_2D_3(生物活性维生素D_3代谢物)在钙稳态中起重要作用。琉球柳叶中的1,25(OH)_2D_3-糖苷是生物活性形式维生素D_3的独特来源,在肠道中分解后可被逐渐吸收并发挥作用。 相似文献
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：２００３年５月－２００４年４月,利用静态箱－气相色谱法对生长季与非生长季三江平原小叶章湿地N2O 通量特征及排放贡献进行了研究。结果表明,生长季N2O 呈脉冲式排放,通量介于０．００５～０．１１１ｍｇ／（ｍ２·ｈ）,５月较低通量与降水较多有关,６月通量骤然增加与冻层融通有关,７－８月与降水少及蒸发旺盛有关,９月与土壤中较多氮有关。N2O 通量与５ｃｍ 地温呈显著正相关（P＜０．０１）;非生长季N2O 表现为“吸收－排放”,通量介于－０．００１５～０．０４９７ｍｇ／（ｍ２·ｈ）。N2O 通量与气温、土壤融化时间均呈指数关系（P＜０．０１）,说明在冻结期,温度仍是控制微生物活性的主要因素,而在融化期,温度和冻层融通是导致N2O 通量迅速增加的重要原因。总之,生长季N2O 排放量为２０５．５４ｍｇN2O／ｍ２,为N2O 的“源”,非生长季N2O 排放量为－２６．９７ ｍｇN2O／ｍ２,为N2O 的“汇”,全年N2O 排放量为１７８．５７ｍｇN2O／ｍ２,为N2O 重要释放“源”。 相似文献
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<正>调节和控制体内钙代谢的重要物质为甲状旁腺激素(PTH),降钙素(CT)和维生素D的活性形式—1、25-(OH)2D3。1奶牛体内钙的代谢过程1.1钙在骨骼中的代谢钙在骨骼中有两种存在方式,绝大多数以CaHPO4的形式紧密结合在骨胶原蛋白基质上,一小部分以离子形式存在于骨细胞外液和骨胞内小 相似文献
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Rafael V. A. Zafalon Larissa W. Risolia Vivian Pedrinelli Thiago H. A. Vendramini Roberta B. A. Rodrigues Andressa R. Amaral Marcia M. Kogika Marcio A. Brunetto 《Journal of animal physiology and animal nutrition》2020,104(1):322-342
Due to the presence of receptors in the cells of numerous body tissues, vitamin D is associated with several physiological functions that go beyond calcium and phosphorus homoeostasis and control of bone metabolism in the body. In humans, several studies have associated lower vitamin D concentrations with numerous diseases, such as cancer, heart disease, autoimmune diseases and infectious diseases, and also with an increase in the total mortality rate of the population. Recently, this nutrient started to gain importance in veterinary medicine, and several articles have shown a correlation between low vitamin D status and diseases unrelated to bone metabolism. The present review aims to highlight the recent publications that investigated this relationship, bringing the evidence that exists so far in dogs and cats. 相似文献
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During different stages of lactation, different requirements of calcium have to be met depending on the milk amount. Vitamin D receptors (VDR) regulate calcium homeostasis by increasing the entry of Ca into blood from bone stores and dietary sources. The purpose of this study was to investigate if age and breed of cows influence VDR amounts across different segments of the gastrointestinal tract. Thirty-six cows were used (18 Brown Swiss, 18 Holstein Friesan, both > 5.5 years or < 4.5 years). Tissue specimens of the intestines were collected from the cows. Formaldehyde-fixed and microwave-treated paraffin sections were used for VDR immunohistochemistry employing a biotinylated monoclonal rat antibody and streptavidin peroxidase technique. The results showed that nuclei and cytoplasm of enterocytes stained positively for VDRs. Strongest immunoreactions were observed in intermediate and basal glandular cells. No significant differences were observed between the different groups. Vitamin D receptors immunoreactivities were prominent in duodenal mucosa, lower in jejunum and in colon, decreased further in ileum and were lowest in caecum. Decreases in number of positively marked cells and staining intensities resulted in reduced immunoreactions. The results of this study indicate that VDR are highly expressed at the site of maximal intestinal calcium absorption. No significant influence of age and breed was observed. The animals used were not in a negative Ca balance. The cows were all in the stage of late or mid lactation. During these periods, the Ca requirements are low and the diets are high in Ca concentration; and the animals are adapted to these circumstances. Passive absorption in adult animals seems to dominate when Ca intake is adequate or high. The active absorption may play a considerably more significant role during the peripartal period, when Ca homeostatic mechanisms are challenged because of tremendous Ca demand at the initiation of lactation. 相似文献
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D. Haxhiu S. Hoby C. Wenker A. Boos M. P. Kowalewski F. Lewis A. Liesegang 《Journal of animal physiology and animal nutrition》2014,98(6):1021-1030
The purpose of this study was to investigate the influence of feeding and UVB exposition on the occurrence and distribution patterns of vitamin D receptors (VDR) and calbindin D28k (Cb‐D28k) in the gastrointestinal tract of veiled chameleons. Thus, 56 veiled chameleon hatchlings were divided into six treatment groups: UV (with UVB exposure); No (no supplements, no UVB exposure); CaAUV (with calcium (Ca), vitamin A supplementation, UVB exposure); CaA (with Ca, vitamin A supplementation); CaADUV (with Ca, vitamin A, vitamin D supplementation, UVB exposure); and CaAD (with Ca, vitamin A, vitamin D supplementation). Animals were reared under the suspected conditions for 6 months on locust‐based diets. Tissue samples of stomach, duodenum, ileum and colon were taken, and semi‐quantitative immunohistochemical methods (IHC) were performed to detect Cb‐D28k and VDR. VDR immunoreactions were higher in the luminal epithelium of the duodenum than in that of the ileum. VDR immunoreactions in the luminal epithelium were higher at the base of the villi of the duodenum as compared to the tip. Cb‐D28k immunoreactions were mainly observed in the luminal epithelium of the duodenum. The two groups treated with all dietary supplements (CaADUV, CaAD) exhibited a higher Cb‐D28k immunoreaction as those with no supplements and UVB exposure only. No immunoreaction for both proteins could be detected in the stomach. This study suggests that the duodenum plays an important role in the active transcellular absorption of Ca in veiled chameleons as shown by the immunohistochemical detection of VDR and Cb‐D28k. Expression of Cb‐D28k, in particular, appears to be regulated by dietary supplementation of vitamin D and vitamin A. VDRs, however, tended to be upregulated when animals were not supplemented with Ca, vitamin D and vitamin A. This may be due to the decreased Ca concentrations which caused vitamin D activation in the skin without any supplementation, but UVB exposure. 相似文献
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乳牛口服大量β-胡萝卜素对维生素D3及钙磷代谢的影响 总被引：1，自引：0，他引：1
６头健康成年荷斯坦乳牛被随机均分为２组。试验组牛第１周每头口服β－胡萝卜素２３．０ｇ,以后每周每头口服１１．５ｇ,对照组不做任何处理。试验期共８周。结果表明,试验组乳牛血清钙及无机磷水平呈下降趋势;血清维生素Ｄ３活性代谢产物２５－ＯＨ－Ｄ３和１,２５－（ＯＨ）２－Ｄ３均呈现明显下降;至第５周末,血液β－胡萝卜素水平最高,２５－ＯＨ－Ｄ３水平下降非常明显。据此认为,乳牛对β－胡萝卜素的吸收存在一阈值,大剂量的β－胡萝卜素进入机体,可能直接干扰维生素Ｄ３的羟化,使其活性代谢产物呈下降趋势,但由于吸收阈值的存在,其对维生素Ｄ３和骨骼钙磷代谢的干扰作用可得到一定程度的减缓。 相似文献
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The purpose of this study was to investigate, if different Ca concentrations in diets have an influence on bone mineral metabolism in growing goats and sheep. Twelve growing goats and sheep were divided into two groups. The two control groups received 6.1 g calcium/day (nG) and 6.7 g calcium/day (nS) for goat and sheep respectively. The other two groups were fed 17.7 g calcium/day (hG) and 18.5 g calcium/day (hS). Blood samples were taken 2, 4, 5 and 6 weeks after the start of the experiment. In serum Ca and vitamin D were determined and bone metabolism was measured using crosslinked carboxyterminal telopeptide of type I collagen (ICTP), crosslaps, bone-specific alkaline phosphatase and osteocalcin (OC). Bone mineral density (BMD) was quantified using quantitative computed tomography. Bone resorption marker (ICTP) concentrations were significantly different between both groups control sheep/control goat and hS/hG, but no significant differences were evident in the different feeding groups within one species. OC concentrations showed a similar course to ICTP. The goats had significantly higher concentrations compared with sheep. The 1,25 dihydroxyvitamin D (VITD) concentrations in both hCa groups were significantly lower than in the control groups. BMD increased in the hCa groups compared with the control groups with the time, but significant differences were only evident in sheep in week 2. The hCa diet did not induce differences between the groups within one species for all bone markers. The control Ca diet seems to improve the active Ca absorption via VITD whereas the hCa diet leads to a higher amount of Ca apparently digested. Higher BMD was only observed in group hS compared with nS. 相似文献