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121.
本试验通过给奶牛饲喂不同粗饲料组合的TMR日粮,探讨日粮中不同粗饲料组合对奶牛泌乳性能的影响.结果表明,日粮鲜重的精粗比从30∶70提高到40∶60后,奶牛的干物质采食量有显著地增加(P<0.05).随着精料比例增加,其能量水平、蛋白含量和乳蛋白率增加.同时,蛋白含量和产奶量都有所提高.在试验二组中用青贮代替了全贮,提高了奶牛的采食量和泌乳性能.说明,奶牛全混合日粮(TMR)可以提高日粮养分表观消化率、产奶量和改善乳蛋白质水平.青贮饲料的蛋白质的降解和利用更容易被瘤胃微生物降解和吸收,从而提高奶牛的泌乳性能,取得较高的经济效益. 相似文献
122.
123.
Satoshi Haga Hiroshi Ishizaki Miwa Nakano Seiji Nakao Kiyoshi Hirano Yoshito Yamamoto Miya Kitagawa Hiroyuki Sasaki Yoshihiro Kariya 《Animal Science Journal》2014,85(2):135-142
Blood total antioxidant capacity (TAC) has become a key bio‐marker for animal health. Forest‐grazing cattle are known to forage various native plants that have high TAC. This study evaluated differences of plasma TAC between forest‐grazing (FG) and pasture‐grazing cattle (PG). Experiment 1 monitored the plasma TAC levels of 32 Japanese Black cattle. The level in PG did not change throughout the grazing period. However, that in FG, which increased from summer, was significantly higher than that in PG through fall (P < 0.05). In experiment 2, we used nine Japanese Black heifers and investigated their blood antioxidant parameters and the TAC in plants that the cattle consumed in late June and September. The plasma TAC levels in FG were significantly higher than those in PG in both periods (P < 0.05). Plasma levels of lipid peroxidation in FG tended to be lower than that in PG (P = 0.098). Furthermore, the TAC levels in various species of shrubs and trees consumed by FG were higher than those in pasture grasses. Results of this study show that plasma TAC of grazing Japanese Black cattle in forestland increase from summer through fall. 相似文献
124.
《Journal of Exotic Pet Medicine》2014,23(2):142-146
The hemodilution effect of manually preheparinized syringes was determined by evaluating the packed cell volume (PCV) and total solids (TS) from blood samples collected from 50 American alligators (Alligator mississippiensis). A volume of 0.2 mL of blood was drawn into 3 syringes of 1 mL: control with no heparin sodium, heparin sodium drawn to 0.1 mL and then expelled, and heparin sodium drawn to 0.2 mL and then expelled. PCV and TS values were determined from each syringe immediately after collection. Mean PCV and TS values were compared between the control and heparin groups using linear mixed modeling. The syringes coated with heparin resulted in a significantly lower mean PCV and TS values when compared with controls, with no significant difference between the heparin groups. This dilution effect was also found to be inconsistent and not accurate from one syringe to another. An adjunct method of obtaining 0.5 mL from already-collected blood samples into 1-mL syringes that were coated with heparin drawn to 0.2 mL and then expelled also showed a significant decrease in PCV and TS values when compared with the control samples, although to a lesser extent. As a result, it cannot be recommended to manually preheparinize syringes when collecting small volume of blood samples from American alligators because significant and unpredictable hemodilution is likely to occur. 相似文献
125.
试验研究了半胱胺(Cs)对藏绵羊断奶羔羊瘤胃pH值、总脱氢酶及TVFA的影响。将10只(公母各半)80日龄左右、体重平均为(16.00±0.31)kg、装有永久性瘤胃瘘管的藏绵羊断奶羔羊随机分为2组(试验组和对照组),在日粮精料中添加300 mg/(kg·BW)的Cs,隔日添加1次,试验期42 d。正式试验当日及试验第7、14、21、28、35天的7:00、9:00、11:00、13:00、15:00、17:00、19:00、21:00、23:00、1:00、3:00、5:00于颈静脉采血样10 mL,同时采集瘤胃液10 mL,测定瘤胃pH值、总脱氢酶的活性和TVFA。检测结果表明,试验组精料中添加Cs使藏绵羊断奶羔羊瘤胃液pH值升高;血清尿素氮浓度降低,与对照组相比差异极显著(P0.01);瘤胃液总脱氢酶活力提高极其明显(P0.01);整个试验期内,半胱胺对瘤胃TVFA的影响极显著(P0.01)。 相似文献
126.
采用不同的测定方法,对6个不同山药品种中的还原糖、总糖及粗多糖进行测定。结果表明:不同品种间的糖含量存在一定的差异,其中‘明豆子’中的还原糖、总糖和粗多糖的含量最高,含量分别为0.1485%、0.3812%、0.2246%,其余品种不同的组分含量有所差异,综合分析‘明豆子’的市场开发价值最高。 相似文献
127.
中华绒螯蟹血淋巴和肝胰腺的总蛋白含量与性早熟的关系 总被引:11,自引:3,他引:11
中华绒螯蟹扣蟹性腺发育与肝胰腺和血淋巴的蛋白质浓度相关.性早熟前后,雌雄扣蟹肝胰腺总蛋白浓度分别由(121.17±44.50)mg@g-1和(89.43±21.86)mg@g-1下降至(81.08±5.84)mg@g-1和(70.58±9.90)mg@g-1,雌性扣蟹的肝胰腺占体重的比值也由8.18%降至3.90%.血淋巴总蛋白浓度正常发育的雌性扣蟹为(99.55±12.06)mg@mL-1,明显高于性早熟雌性扣蟹的(72.26±17.87)mg@mL-1;而雄性扣蟹性早熟前后的血淋巴总蛋白浓度无显著差异.肝胰腺总蛋白浓度二秋龄雌蟹高于性早熟雌性扣蟹,但它们之间的血淋巴总蛋白浓度没有显著差异.二秋龄雄蟹的血淋巴和肝胰腺总蛋白浓度与性早熟雄性扣蟹相当,差异不显著. 相似文献
128.
Carmen Murcia Laura Coello Rogelio Fernández María Jesús Martín Fernando Reyes Andrés Francesch Simon Munt Carmen Cuevas 《Marine drugs》2014,12(2):1116-1130
Tanjungides A (1) (Z isomer) and B (2) (E isomer), two novel dibrominated indole enamides, have been isolated from the tunicate Diazona cf formosa. Their structures were determined by spectroscopic methods including HRMS, and extensive 1D and 2D NMR. The stereochemistry of the cyclised cystine present in both compounds was determined by Marfey’s analysis after chemical degradation and hydrolysis. We also report the first total synthesis of these compounds using methyl 1H-indole-3-carboxylate as starting material and a linear sequence of 11 chemical steps. Tanjungides A and B exhibit significant cytotoxicity against human tumor cell lines. 相似文献
129.
Sponges corresponding to the Jaspidae family have proved to be a prolific source of bioactive natural products. Among these, the bengamides and the bengazoles stand out by virtue of their unprecedented molecular architectures and impressive biological profiles, including antitumor, antibiotic and anthelmintic properties. As a consequence, intense research activity has been devoted to these compounds from both chemical and biological standpoints. This review describes in detail the research into these classes of natural products and the benefits they offer in chemistry and biology. 相似文献
130.