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991.
为探讨有机硒和无机硒对肉兔生长性能和抗氧化功能的影响,试验选用100只35日龄断奶仔兔,公母各半,随机分为5组,每组5个重复,每个重复4只。Ⅰ组为对照组,饲喂基础日粮;Ⅱ、Ⅲ组在基础日粮中分别添加0.15、0.30 mg/kg的亚硒酸钠,Ⅳ、Ⅴ组分别添加0.15、0.30 mg/kg 的硒代蛋氨酸。预试期7 d,正式期28 d。结果表明:各硒源添加组日增重均显著高于对照组(P<0.05),其中Ⅳ的日增重最高,料肉比最低,显著低于对照组。Ⅱ、Ⅲ、Ⅴ组间日增重和料肉比差异均不显著(P>0.05)。Ⅳ组的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化轻酶(CAT)活性均显著高于Ⅰ、Ⅱ组(P<0.05),丙二醛(MDA)含量显著低于Ⅰ组和Ⅱ组(P<0.05),但Ⅲ、Ⅳ组间各抗氧化指标差异均不显著(P>0.05)。由此可见,一定剂量的硒能提高肉兔生长性能和抗氧化功能,且有机硒的添加效果优于无机硒。  相似文献   
992.
探讨反相微乳液法制备的β-纳米磷酸三钙/明胶/鹿茸多肽复合材料(简称纳米复合材料)对人成骨细胞功能的影响.利用反相微乳液法制备纳米复合材料,扫描电镜观察其形态,EDX与SELDI-TOF-MS分析对复合材料进行表征.采用MTT比色法、茜素红染色法检测纳米复合材料对体外培养的人成骨细胞hFOB1.19的增殖、矿化结节形成的影响;采用全自动生化分析仪检测hFOB细胞碱性磷酸酶活性(ALP).结果表明该纳米复合材料可促进人成骨细胞增殖,提高ALP活性并增加矿化结节形成的数量,可促进人成骨细胞的增殖、分化成熟及矿化.  相似文献   
993.
The effect of selenium (Se) and vitamin E (Vit. E) on reproductive performance, growth and health was studied in pigs. Two levels of Se were used, 0.03 and 0.06 nag per kg feed. The major component of the experimental diets was barley originating from soil which had formerly produced crops with a very low content of Se. Prior to seeding, the area was divided into 2 plots, 1 of which was treated with Se in the form of sodium selenite, 100 g Se per ha. The use of Se enriched fertilizer was an effective way of increasing the Se concentration of the grain. Thus the concentration of Se in the barley produced on the treated area was 5 times higher than in barley from the untreated one.Vit. E was added at a level of 30 i.u. per kg feed, and the concentrations were approx. 15 and 45 i.u. in the basal and experimental diets, respectively.The higher level of Se or Vit. E was not significantly associated with milk yield of the sow, litter size, birth weight or haemoglobin levels. However, there was a tendency to an increase in milk yield of the sows following additions of Se plus Vit. E, and litter size was slightly higher from sows which had received an addition of Vit. E. The concentration of Se and Vit. E was much higher in colostrum than in sow milk, and additions of dietary Se and Vit. E were associated with marked increases in the concentrations of these compounds in both colostrum and sow milk. There was a moderately improving effect of a high Se concentration in feed on growth rate and feed utilization. Low dietary levels of Se and Vit. E were followed by increased mortality rate in piglets; iron toxicity in connection with iron treatment was observed in piglets on low dietary Vit. E. Symptoms characteristic of PSE were not observed in the Se and Vit. E deficient pigs.  相似文献   
994.
硒与癌肿的关系是一个十分引人注意的问题,为此对硒的分析方法的探索也愈来愈多。荧光分析法具有灵敏度高、选择性强、操作简便等优点而被广泛地采用。用荧光法准确测定生物样品中的硒含量,关健在于样品消化。目前广泛采用硫酸与高氯酸的混合酸,加钼酸钠作为催化剂进行消化,这种消化方法终点难以控制,误差较大。本文采用聚四氟乙烯内衬不锈钢消化罐,用1:3硝酸—高氨酸加压分解。实验结果表明,本体系的重复性和回收率都令人满意,适用于生物样品的测定。  相似文献   
995.
硒源对肉仔鸡生长性能及其在肝脏中沉积量的影响   总被引:1,自引:1,他引:0  
基础日粮中添加有机硒和无机硒,饲喂1日龄艾维茵肉仔鸡,以基础日粮为对照,分别于28,49日龄测定其生长性能,并测定49日龄时肝脏中硒沉积量.结果表明,有机硒和无机硒均能促进肉仔鸡的生长性能.在肝脏中,有机硒沉积明显优于无机硒.有机硒是较好的硒源.  相似文献   
996.
Retained placenta, endometritis, cystic ovaries and low conception rates are often considered as interconnected conditions in cattle. Wide ranges in amounts of selenium and vitamin E supplements have been advised in late-pregnancy diets and, frequently, they can be synergistically beneficial. Animals at grass or with other green foods should be of adequate vitamin E status, but dietary selenium deficiencies are both more frequent and severe. Selenium status is important for superovulation in cattle and multiple births in ewes because of its importance in sperm transport and establishment of ova. However, the potential toxicity of selenium-enriched feed supplements restricts their use on a free-access basis. Giving sodium selenite or selenate by injection provides only a short-term response in the plasma. Barium selenate given in oil by injection provides a more durable response but has potential tissue residue problems. Compressed metallic selenium powder with iron powder in high-density reticulo-ruminal pellets gives sustained release, but uncertainties regarding possible surface coating and the variable effects of selenium particle size may require additional grinders to ensure prolonged release. Neither reticulo-ruminal pellets of such composition nor barium selenate by injection may be used worldwide because only sodium selenite and selenate have general regulatory approval. A sustained-release multi-trace element/vitamin rumen bolus system effective for several months has increased lambing percentages in ewes, and increased herd conception rates and reduced the spread of calving for herds of beef cattle.  相似文献   
997.
硒的生物学功能及其机理研究   总被引:11,自引:0,他引:11  
本文综述了微量元素硒的生物学功能研究进展,包括硒的生物大分子化合物的种类、硒在免疫、抗癌方面的作用研究现状,硒与维生物E和其它微量元素的互作,以及硒生物学功能机理的研究成果。同时对生命科学领域的硒研究中尚待深入的问题进行了初步探讨。  相似文献   
998.
Two experiments (Exps. II and III) were performed with colonic material from swine dysentery as inoculum. The results of Exp. II showed that the inoculation produced less pronounced clinical signs and patho-morphological lesions and also affected fewer pigs in the groups supplemented with vitamin E and selenium than in the group not given a corresponding supplementation. It is therefore concluded that the daily supply of these 2 nutritional factors significantly increased the resistance to swine dysentery. The cod liver oil incorporated in the diet of 2 groups in Exp. II had also a positive effect in this respect. In Exp. III the inoculation of the pigs fed only the basic ration (Group 1) produced relatively moderate clinical signs and patho-morphological lesions in half of the animals, the results in the rest of the group are, however, in accordance with the observations in the corresponding groups of the 2 preceding experiments. The other results of Exp. III indicate an increased resistance to swine dysentery in the group with selenium as the only supplement. However, no equivalent condition could be demonstrated when a similar supplement of vitamin E was used. The pigs in Exp. III given both nutritional factors showed perhaps the best resistance to swine dysentery, especially when the patho-morphological lesions are taken into consideration.  相似文献   
999.
1000.
Blood selenium levels were found to fluctuate throughout the year, being highest during the indoor season when the greatest amounts of compound concentrates were fed. From October to January the average blood selenium levels increased from 0.10 μg/ml to 0.18 μg/ml (15 cows). Subcutaneous injections of barium selenate (500 mg selenium) increased the blood selenium levels significantly. The treated group (15 cows) reached average levels of about 0.21 μg/ml blood during the indoor season.The effect of oral supplementation of sodium selenite (for 2 months) on the levels of plasma selenium, blood selenium and glutathione peroxidase activity was investigated. Plasma selenium was found to give an immediate reflection of the daily selenium intake. Maximum activity of glutathione peroxidase was reached 1 month after the end of the supplementation period.It is concluded that if selenium enriched concentrates are used in a normal feeding regimen, further supplementation with selenium does not seem to be necessary.  相似文献   
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