提高奶牛繁殖率的技术措施

随着奶牛业的发展，提高奶牛的繁殖率显得越来越重要。提高奶牛繁殖率，缩短产犊间隔，对于提高奶牛产奶量和奶牛生产经济效益具有重要意义。通过改善饲养管理条件、合理应用现代繁殖技术来提高繁殖率，可达到提高产奶量的目的。笔者结合实际，介绍如何提高奶牛繁殖率技术措施，供同行和养殖户参考。     

奶牛发情数字化检测方法研究现状与发展

为适应我国奶牛养殖业对大规模、集约化奶牛养殖的需求，提高奶牛养殖场经济效益，本文针对奶牛发情的数字化检测方法进行了综述。传统人工观察法工作量大、检出率低，而且不易检出夜间发情奶牛|数字化检测方法提高了奶牛发情检出率，但是大多数发情检测装置为接触式设备，这会影响奶牛的发育，也会对奶牛的产奶量造成影响。因此，应研究出非接触式奶牛发情检测装置与技术，减少对奶牛的伤害，提高奶牛养殖业现代水平。 [关键词] 奶牛发情|数字化检测|接触式设备|非接触式设备     

如何提高奶牛场户经济效益

近几年来，各地涌现出一批又一批奶牛专业村、场和户。如何提高奶牛场户的经济效益，逐渐成了奶牛饲养场户普遍关注的问题。现将提高奶牛场户经济效益的方法和措施总结如下。 1提高奶牛的遗传性状 　　同是奶牛，但品质相差很大，国外最优质的荷斯坦奶牛个体，一个泌乳期产奶达 2.5万～ 3万千克，而国内差的奶牛个体一个泌乳期仅产奶 4000～ 6000千克。所以，要想提高奶牛的个体产奶量，首先要提高奶牛的品质。因此，必须根据奶牛群的结构、品种、每头奶牛的来源和优缺点，加强奶牛选配工作，即选择那些体型外貌好、生产性能高和遗传性能优…     

奶牛养殖小区的管理要点

近几年来，奶牛养殖业发展迅速，奶牛存栏量大幅增加，奶牛养殖小区（托牛所）的数量像雨后春笋般快速发展起来，对促进奶牛业发展，提高奶牛集约化、规模化程度，提高牛奶质量，提高奶牛饲养管理水平起到了重要作用。为了使奶牛养殖小区稳步向前发展，在管理上要注意以下几点：[第一段]     

奶牛良种(冻精)补贴专项申报指南

一、项目支出目标.2005年在全国奶业优势区域内选择部分县，实行奶牛良种(冻精)补贴试点，在项目县全面推广奶牛优质冻精，对使用优质奶牛冻精奶牛养殖户给予补贴，提高农民使用优质奶牛冻精的积极性，加速优质奶牛冻精的推广，改善牛群品质，提高奶牛养殖的效益。     

提高奶牛"三率"的几项措施

如何提高奶牛生产水平，安全生产，使饲养成本降到最低，增加养殖经济效益，结合我县奶牛生产现状及养殖经验，认为提高奶牛“三率”，是提高养殖经济效益最有效的途径。现浅谈如下几项措施，供奶牛养殖户借鉴。     

应用二氢吡啶饲喂奶牛效果观察

提高奶牛生产性能，挖掘奶牛遗传潜力，延长奶牛使用寿命，是畜牧工作者长期面临的课题。因此，进行了应用二氢吡啶饲喂奶牛试验，取得了满意的经济效果。为奶牛业降低饲养成本，提高奶牛单产和牛奶质量提供了新途径。     

养殖户如何提高奶牛繁殖成活率

在奶牛生产中，如何充分发挥高产奶牛自身的繁殖潜力，快速提高奶牛的繁殖率，成为养殖户共同关心的问题。为此，笔者就如何提高奶牛繁殖率作一简要介绍，希望对养殖户有所裨益。     

奶牛子宫内膜炎的病因及防治

随着奶业生产的发展，充分提高和发挥奶牛的生产性能，提高奶牛产量就尤为重要。但是除了奶牛本身的生产性能外，奶牛子宫内膜炎疾病是影响奶牛产量的重要因素。就目前生产而言，奶牛发生子宫内膜炎不仅严重影响了奶牛的繁育性能和产奶量，严重者可丧失经济价值而淘汰。     

安全使用奶牛配合饲料四注意

1 合理选择饲料 根据奶牛的生理阶段、产奶量，选择合适的奶牛饲料，不但可以提高奶牛的生产性能．还可降低成本。提高饲养奶牛的经济效益。     

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.