紫花苜蓿饲喂奶牛试验研究

紫花苜蓿具有产草量高,营养物质含量高等特点,通过紫花苜蓿饲喂奶牛试验,对提高产奶量、奶质有关参数,指导奶农改变长期以来以精料、秸秆、少量天然牧草为主饲喂奶牛的方式提供依据.     

过瘤胃蛋氨酸对奶牛产奶量以及乳成分的影响

选用16头泌乳中期奶牛,每头牛饲喂过瘤胃蛋氨酸(SmartamineTM)0、8、12和16g/d,研究其对泌乳中期奶牛产奶量以及乳成分的影响。结果表明,与对照组相比,补饲12和16g/d过瘤胃蛋氨酸能提高泌乳中期奶牛产奶量,补饲8g/d过瘤胃蛋氨酸奶牛产奶量下降5.73%;12g/d组产奶量提高0.62%,但差异均不显著;16g/d组产奶量提高10.84%,差异显著。补饲过瘤胃蛋氨酸能提高乳蛋白率和乳脂率水平,但差异不显著。补饲16g/d过瘤胃蛋氨酸牛奶乳蛋白量提高11.49%,乳脂肪量提高了13.11%。     

保护性脂肪对对奶牛乳成分的影响

影响奶牛乳成分的因素很多，其中饲粮条件是影响乳成分的决定性因素。保护性脂肪属于过瘤胃脂肪，研究表明，在日粮中添加保护性脂肪能够提高奶牛的产奶量和乳脂率。本试验结果表明，保护性脂肪能够极显著地提高乳脂率（p＜0.01），并使乳密度显著降低（p＜0.05），对产奶量、乳蛋白质和非脂乳固形物的含量影响不大（p＞0.05）。     

如何喂奶牛保护性脂肪

<正>保护性脂肪应用于奶牛,能提高奶牛产奶量,改善奶质,降低应激危害和提高奶牛的繁殖性能等。保护性脂肪喂奶牛好处多,是一项新技术,具体操作时应注意:1选择保护性脂肪产品的类型在实际生产中应选择保护性脂肪产品中碳链短的脂肪酸,因其进入肠道后吸收好,利用率高。还要注意选择不饱和脂肪酸,可比饱和性脂肪酸好吸收、效果好。若在生产中     

奶牛饲喂保护性脂肪的注意事项

保护性脂肪是用动物瘤胃难解的一些物质,包被于油脂表面,使其避免受瘤胃发酵的作用,从而达到保护脂肪不被瘤胃破坏的目的.脂肪进入小肠后即可被充分消化、吸收和利用.保护性脂肪应用于奶牛能提高奶牛产奶量,改善奶质,降低应激危害和提高奶牛的繁殖性能.保护性脂肪喂奶牛,是一项新技术,喂牛前必须注意到6个问题,才能达到理想的目的,否则将适得其反,起不到应有的作用或产生副作用.     

奶牛分娩前后的饲养和管理技术

一、分娩前后饲料喂量在干奶期,饲喂的精料量与奶牛产后发生难产和酮病有关.过去在饲养干奶牛时都以喂粗料为主,但在实际中粗料往往供给不足,于是分娩后奶牛常会出现营养失调.此外,由于产后奶牛在较短时间内可达到泌乳高峰,所以在产后给奶牛停料或将配合饲料量限制在14-15公斤时,常会造成营养不足、产奶量下降、繁殖机能衰退.提高奶牛分娩后的饲喂量(保证采食18公斤),和补饲优质粗料,其最高日产奶量可达到40公斤.因此,需研究高产奶牛高能饲料的喂量、精、粗料的比例和饲喂方法.     

饲喂优质精料有益于奶牛

英国国家农业中心（NAC）奶牛研究机构的最新研究成果表明，给高产奶牛饲喂大量的优质精饲料，产奶量可以提高20％。该机构所设计的饲料替换方案，无论对低产奶牛，还是对高产奶牛群都有效果。尽管每头奶牛所用的精饲料成本相当高，但产奶量的增加仍显示出可取得相当可观的经济效益。他们进行了饲喂对比试验。将该中心的牛群分为两组，两组牛泌乳量和产犊日期均相同。所有的牛喂同样质量的青饲料──一种青贮玉米、尿素处理过的整株小麦和青贮牧草的混合饲料。第一组的63头奶牛补饲常规饲料，试期内头均产奶5800升。第二组的55头奶牛补饲…     

高寒地区高产奶牛补饲胡萝卜的好处及注意事项

在北方高寒地区,以胡萝卜补饲高产奶牛,可以提高其产奶量,同时还能提升其抵御寒冷和抗病的能力。值得注意的是补饲高产奶牛胡萝卜时宜生食,不宜过量,最好切碎后饲喂,不饲喂冰冻或霉变的胡萝卜。     

多年生紫花苜蓿饲喂奶牛试验研究

紫花苜蓿营养丰富,是奶牛饲草的最佳粗饲料,不论青饲还是调制成干草,适口性都很好,用于饲喂奶牛可显著提高奶牛产奶量,增加奶农户经济收入。     

紫花苜蓿饲喂奶牛试验

通过紫花苜蓿Medicago sativa饲喂奶牛对比试验,结果发现:紫花苜蓿营养丰富,是饲喂奶牛的最佳粗饲料,不论青饲还是调制成干草,适口性都很好,可显著提高奶牛产奶量,增加奶农户经济收入.充分利用兰州市紫花苜蓿的资源优势, 增加奶牛日粮中紫花苜蓿的比例,提高奶牛单产水平,降低生产成本,提高经济效益,通过示范户的带动,大力推广种植紫花苜蓿,改变奶农户以精料为主的传统饲养方式.     

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。     

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。     

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。     

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。     

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

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.