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361.
选择30日龄体重基本一致的齐卡兔60只(公、母各半),随机分成5组,其中对照组饲喂基础日粮,试验组分别在基础日粮中添加喹赛多50 mg/kg、喹赛多100 mg/kg、喹乙醇50 mg/kg和喹乙醇100 mg/kg,进行为期60 d的饲养试验;研究喹赛多和喹乙醇对肉用齐卡兔生产性能的影响.结果表明:试验组与对照组相比,平均日增重提高显著(P<0.05);100 mg/kg喹赛多组与对照组日耗料量相当,而其它各组日耗料量则显著低于对照组(P<0.05);试验组与对照组相比料重比降低显著(P<0.05),但试验组间差异不显著(P>0.05);试验组肉兔腹泻率降低.喹赛多组优于喹乙醇组,其适宜添加量为100 mg/kg. 相似文献
362.
Jesus Sevillano Morales Alicia Moreno-Ortega Manual Angel Amaro Lopez Antonio Arenas Casas Fernando Cámara-Martos 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(9):1739-1748
This study aimed to estimate the consumption of meat and products derived from hunting by the consumer population and, specifically, by hunters and their relatives. For this purpose, a survey was conducted on the frequency of consuming meat from the four most representative game species in Spain, two of big game, wild boar (Sus scrofa) and red deer (Cervus elaphus), and two of small game, rabbit (Oryctolagus cuniculus) and red partridge (Alectoris rufa), as well as of processed meat products (salami-type sausage) made from those big game species. The survey was carried out on 337 habitual consumers of these types of products (hunters and their relatives). The total mean game meat consumption, per capita in this population group, is 6.87 kg/person/year of meat and 8.57 kg/person/year if the processed meat products are also considered. Consumption of rabbit, red partridge, red deer and wild boar, individually, was 1.85, 0.82, 2.28 and 1.92 kg/person/year, respectively. It was observed that hunters generally registered a larger intake of game meat, this being statistically significant in the case of rabbit meat consumption. Using probabilistic methods, the meat consumption frequency distributions for each hunting species studied were estimated, as well as the products made from big game species and the total consumption both of meat by itself and that including the products made from it. The consumption frequency distributions were adjusted to exponential ones, verified by the test suitable for it according to Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), the Chi-squared and Kolmogorov–Smirnov statistics. In addition, the consumption percentiles of the different distributions were obtained. The latter could be a good tool when making nutrition or contaminant studies since they permit the assessment of exposure to the compound in question. 相似文献
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364.
The process of corneal endothelial wound healing was studied using laser and tandem scanning confocal microscopy (LSCM and TSCM). Following transcorneal freeze (TCF) injury, rabbit corneas were observed using ex vivo LSCM and in vivo TSCM. LSCM revealed the intracellular actin filament organization which, stained with phalloidin-FITC, in migrating endothelial cells, transformed fibroblast-like cells, stroma keratocytes, and epithelial cells during wound healing in corneal tissue. The TSCM provided sequential spatial observation of morphologic changes from endothelium to epithelium of the cornea during in vivo cellular repair of wound healing noninvasively on the same cornea without animal sacrifice. Ex vivo LSCM supported the morphologic analysis of the in vivo TSCM observations. 相似文献
365.
采用聚乙二醇(polyethylene glycol,PEG)对β-乳球蛋白(β-lactoglobulin,β-LG)羧基共价修饰,探究PEG修饰及PEG化程度对β-LG抗原性和结构的影响。结果表明:总修饰率为82.91%;使用SP?Sepharose?Fast?Flow阳离子交换柱分离纯化,获得纯度分别为99.66%和98.61%的两种主要修饰产物;十二烷基硫酸钠-聚丙烯酰胺凝胶电泳及基质辅助激光解析电离飞行时间质谱鉴定产物分子质量分别为23.3?kDa和28.6?kDa,为单修饰产物(mono-PEG-β-LG)及两点修饰产物(di-PEG-β-LG)。β-LG、mono-PEG-β-LG和di-PEG-β-LG的间接竞争酶联免疫吸附测定半抑制浓度(IC50)分别为1.90、2.47?μg/mL和10.41?μg/mL;mono-PEG-β-LG和di-PEG-β-LG的IC50分别是β-LG的1.30?倍和5.48?倍,表明提高PEG修饰程度可极显著降低β-LG的抗原性。mono-PEG-β-LG和di-PEG-β-LG的游离巯基含量分别为42.70?μmol/g和37.97?μmol/g,表明PEG化程度增强,遮蔽作用增强。表面疏水性和内源荧光分析表明,mono-PEG-β-LG只发生了三级结构变化,而di-PEG-β-LG二级结构水平同时发生变化,表明PEG修饰后β-LG空间结构的改变可能是导致其构象表位破坏和抗原性下降的因素。PEG分子遮蔽可能是导致修饰产物抗原性降低的另一原因。PEG共价修饰β-LG可以显著降低后者的抗原性,且随PEG化程度增大β-LG抗原性降低幅度增加。 相似文献
366.
367.
采用黄芪、党参、当归、女真子、神曲、苍术、补骨脂、益母草 8味中药 ,以灌胃法研究它们对小鼠肝脏、脾脏和睾丸质量及血液生理指标的影响和对兔离体肠段运动的影响 .结果表明 :这些中药能提高小鼠肝脏、脾脏和睾丸的相对质量 ,提高白细胞、淋巴细胞和血糖的水平 ,抑制兔离体肠段的运动 ;这些中药通过提高动物的抗病能力、繁殖能力和食物的消化力而提高动物的生产性能 相似文献
368.
Peter J. Watson Flora Gr?ning Neil Curtis Laura C. Fitton Anthony Herrel Steven W. McCormack Michael J. Fagan 《Journal of the Royal Society Interface》2014,11(99)
Multi-body dynamics is a powerful engineering tool which is becoming increasingly popular for the simulation and analysis of skull biomechanics. This paper presents the first application of multi-body dynamics to analyse the biomechanics of the rabbit skull. A model has been constructed through the combination of manual dissection and three-dimensional imaging techniques (magnetic resonance imaging and micro-computed tomography). Individual muscles are represented with multiple layers, thus more accurately modelling muscle fibres with complex lines of action. Model validity was sought through comparing experimentally measured maximum incisor bite forces with those predicted by the model. Simulations of molar biting highlighted the ability of the masticatory system to alter recruitment of two muscle groups, in order to generate shearing or crushing movements. Molar shearing is capable of processing a food bolus in all three orthogonal directions, whereas molar crushing and incisor biting are predominately directed vertically. Simulations also show that the masticatory system is adapted to process foods through several cycles with low muscle activations, presumably in order to prevent rapidly fatiguing fast fibres during repeated chewing cycles. Our study demonstrates the usefulness of a validated multi-body dynamics model for investigating feeding biomechanics in the rabbit, and shows the potential for complementing and eventually reducing in vivo experiments. 相似文献
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370.
Oxidation of raw and cooked rabbit burgers was compared with that of raw and cooked chicken burgers under different storage conditions using the thiobarbituric acid (TBARS) assay. Rabbit meat had higher TBARS during refrigerated storage than chicken, which has been reported as more susceptible to oxidation than red meats. The oxidative stability of rabbit and chicken burgers was increased with vacuum-packaging. Cooked rabbit had higher TBARS than raw burgers. Lipid oxidation may limit the shelf-life of cooked rabbit meat. 相似文献