奶牛酒精阳性乳与自由基代谢及乳腺损伤关系的研究

对酒精阳性乳患牛衄清与乳清中的抗氧化指标进行了检测，从自由基代谢与损伤的角度探讨了酒精阳性乳的发病机理；同时检测了阳性牛血清与全乳中微量元素Zn、Cu、Mn、Fe的含量，分析了微量元素含量变化与自由基代谢的关系。试验结果显示阳性牛体内发生了过度的过氧化反应，机体总抗氧化能力下降，机体的扰氧化系统已不能有效地清除活性氧及代谢产物，过多的氧自由基可能对乳腺上皮分泌细胞细胞膜造成微损伤，从而引起乳腺细胞分泌异常乳。     

奶牛酒精阳性乳与微量元素Zn、Cu、Mn、Fe含量及自由基代谢的关系

对酒精阳性乳患牛全乳、乳清、血清中Zn、Cu、Mn、Fe的含量进行了检测，同时检测了乳清与血清中的抗氧化指标。结果表明：阳性牛乳清与血清中超氧化物歧化酶（superoxide dismutase，SOD）、谷胱甘肽过氧化物酶（glu—tathione peroxidase，GSH—Px）活性均降低，丙二醛（malondialdehyde，MDA）含量升高；全乳、乳清、血清中zn含量均极显著降低，血清Mn、Fe含量略低，乳清Cu含量降低。综合分析，酒精阳性牛机体总抗氧化能力下降，不能有效清除氧化代谢产物，以至于过多的氧自由基对乳腺上皮细胞膜造成损伤，从而引起乳腺细胞分泌异常乳。     

乳牛硒、碘代谢与酒精阳性乳的关系

通过分析酒精阳性乳患牛血清与乳清中硒(Se)和碘(Ⅰ)含量变化以及相关激素、酶水平的检测,探讨了机体Se、Ⅰ代谢与酒精阳性乳症发生的关系。试验结果显示酒精阳性乳患牛血清与乳清中Se、Ⅰ严重缺乏,谷胱甘肽过氧化物酶(GSH-Px)活性显著降低,甲状腺激素T3、T4水平显著降低。综合分析,酒精阳性乳患牛甲状腺机能低下;机体整体与乳腺局部Se和Ⅰ代谢紊乱,乳腺组织的代谢异常可能导致异常乳的分泌。     

奶牛酒精阳性乳中锌代谢水平与相关酶活力关系的研究

本文对酒精阳性乳中锌(Zn)的含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)、肌酸激酶(CK)4种酶的活性进行了检测,探讨Zn的代谢水平与相关酶活力变化的关系。结果表明:因阳性乳中Zn严重代谢紊乱而致使SOD、GSH-Px活性显著下降,CK活性极显著降低和LDH活性极显著升高;酶的活力变化进一步证实乳腺上皮分泌细胞受到一定程度的损伤,细胞膜的微损伤可能导致奶牛分泌异常乳。     

低酸度酒精阳性乳患牛乳汁蛋白组分及氨基酸含量变化

采用聚丙烯酰胺凝胶电泳和酸水解法对低酸度酒精阳性乳患牛乳汁中蛋白组分及17种氨基酸含量进行了测定。结果显示,酒精阳性乳患牛乳汁中总蛋白、SA、lgG-H、-αLG、-βLG相对百分含量无显著变化(P0.05),tCN相对百分含量显著降低(P0.05);在酪蛋白中,-αCN相对百分含量无显著变化(P0.05),-βCN相对百分含量上升(P0.05),-κCN相对百分含量极显著下降(P0.01);17种氨基酸中,Cys含量极显著下降(P0.01),而Arg含量极显著上升(P0.01),Leu含量亦呈上升趋势(P0.05)。结果表明,酒精阳性乳患牛乳汁中主要蛋白组分及氨基酸的含量均发生了变化,乳汁中酪蛋白微球的稳定性遭到了严重破坏,乳汁胶体的稳定性降低,导致酒精试验呈阳性反应。     

不同浓度酒精滴定阳性乳成分及其矿物质含量比较研究

本试验的研究目的是比较不同酒精浓度阳性反应乳的乳常规成分以及矿物元素含量之间的差异,来评估酒精阳性乳的营养价值。随机选取处在泌乳中期荷斯坦泌乳牛120头,收集奶样,用浓度分别为70%、72%、75%、78%、80%的酒精进行检测。结果表明,不同酒精浓度阳性反应乳的乳脂、乳蛋白、乳糖、无脂固形物的含量没有显著差异(P0.05)。根据滴定浓度可以判定酒精阳性乳与正常乳之间常规营养成分没有显著差异,尚存在利用价值;不同酒精滴定浓度阳性反应乳中Ca、Mg、Na、K、Cu、Zn、Mn、Fe存在显著差异(P0.05),低酸度酒精阳性乳中Ca、Mg含量显著高于正常乳(P0.05),Na、K的含量显著低于正常乳(P0.05),Mn、Zn的含量极显著低于正常乳(P0.01),而Cu、Fe的含量极显著高于正常乳(P0.01)。从一些对人体有益的微量元素含量来看,酒精阳性乳营养价值低于正常乳,其保健作用低于正常乳;但从常规乳成分含量看,酒精阳性乳并未失去利用价值,今后有必要从乳品加工方面进行研究,寻求一条加工利用酒精阳性乳的有效途径。     

酒精阳性乳奶牛血、乳尿酸和胆固醇水平分析

为探索奶牛酒精阳性乳的强度与血清、鲜乳尿酸和胆固醇水平的关系,用68%的酒精全群检测酒精阳性乳,72%的酒精测定68%的酒精阴性牛牛乳,75%的酒精测定72%的酒精阴性牛牛乳,在75%酒精阴性牛群(对照组)、阳性牛群,72%酒精阳性牛群和68%酒精阳性牛群各选择产奶量、胎次、年龄、泌乳期相近的奶牛6头.分别组成Ⅰ、Ⅱ、Ⅲ、Ⅳ组.连续3周采集各组奶牛的鲜乳和颈静脉血液,测定血清和鲜乳中的尿酸与胆固醇含量.结果表明,Ⅱ、Ⅲ、Ⅳ组牛血清尿酸水平显著增加,Ⅲ、Ⅳ组牛鲜乳尿酸水平显著增加(P＜0.05,P＜0.01),且血清和鲜乳中的尿酸水平有随酒精阳性乳强度的增加而增加的趋势;血清和鲜乳中胆固醇水平各组差异均不显著.由此可见,高尿酸血症可能是引起奶牛酒精阳性乳的主要原因,而奶牛酒精阳性乳与血、乳胆固醇水平无关.     

酒精阳性乳患牛血清及乳清离子和微量元素分析

通过检测不同酒精阳性乳血清和乳清中Ca²⁺、Mg²⁺、Na⁺、K⁺浓度及Cu、Zn、Fe、Mn含量,探讨其与酒精阳性乳的关系,结果显示,酒精阳性乳患牛体内的微量元素Zn、Cu和Fe代谢紊乱,会导致抗氧化酶的活性降低、毒性产物含量升高而使自由基代谢平衡紊乱,且Zn、Cu含量的缺乏会降低机体的免疫力;患牛乳中过多的Ca²⁺、Mg²⁺中和酪蛋白微胶粒表面的电荷,导致酪蛋白稳定性下降,致使乳胶体聚集能力增强;这些都易导致酒精阳性乳的形成。     

新型预混料对奶牛酒精阳性乳防治作用的研究

为了验证针对酒精阳性乳（alcohol positive milk,AMP）发病机理制作的新型预混料对奶牛酒精阳性乳的防治效果,本研究设计了试验1和试验2：在试验1中,根据泌乳天数、酒精阳性乳程度,采用完全随机区组方法将100头荷斯坦泌乳后期牛分为对照组、低剂量（LDG）、中剂量（MDG）和高剂量组（HDG）,每组5个重复,每个重复5头牛,各组在日粮中依次添加0、50、100和150 g/（头·d）新型预混料,试验期26 d,3 d为1个采样周期;在试验2中,按照试验1的分组方法,将370头荷斯坦泌乳后期奶牛分为对照组和试验组,每组185头,在日粮中依次添加0和100 g/（头·d）新型预混料,试验期35 d,每5 d为1个采样周期。将奶样与等量的75%中性酒精混合,通过观察奶样状态判断酒精阳性乳发生程度。试验1结果表明,与对照组相比,在日粮中添加50 g/（头·d）新型预混料对酒精阳性乳的发生率有一定的影响（P>0.05）;日粮中添加100和150 g/（头·d）新型预混料能显著降低酒精阳性乳发生率（P<0.05）,尤其对降低强阳性酒精阳性乳发生率效果极显著（P<0.01）,但两组之间差异不显著（P>0.05）。试验2结果表明,到试验结束时,日粮中添加100 g/（头·d）新型预混料可使酒精阳性乳总发生率降低75.73%,强阳性酒精阳性乳发生率降低90.82%。以上结果表明,新型预混料能有效防治奶牛酒精阳性乳的发生,且日粮中新型预混料的最佳添加量是100 g/（头·d）。     

酒精阳性牛乳的发生及其与热应激的关系研究

本文检测了牛乳及牛血清中的无机离子浓度和乳酸脱氢酶、肌酸激酶活性,同时, 检测了牛血清皮质醇含量和3种抗氧化指标。分析表明:酒精阳性乳患牛血清、全乳中无机离 子代谢表现紊乱,酶活性发生改变,机体总抗氧化能力下降。并从热应激角度对其进行了综合 分析。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

獭兔睾丸的组织学观察

家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1　材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5～ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2　结果和讨论2 .1　睾丸定量组织学指标的测定结果　见表 1。表 1　獭兔睾丸定量组织学指标　　　μm,个 /精细管60日龄 75日龄 90日龄曲细精管…     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Observations of fracture of the anconeal process of the ulna of swine

Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a "tight," restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a "buttress callus" which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process.     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.