蛋重和蛋形指数对溧阳鸡种蛋孵化性能的影响

禽蛋的人工孵化是现代家禽业生产经营过程中的关键环节，是现代家禽快速繁衍的重要方法，在家禽的繁殖和生产经营中具有相当重要的位置。所以孵化率的高低一直是种禽场和孵化场所关心的重要问题，它直接关系着种禽场和孵化场的经济效益，研究解决与之相关的诸多因素对指导家禽生产具有重要的意义。种蛋品质是影响种蛋孵化率的重要因素。     

影响鸡种蛋孵化效果的因素探讨

正禽蛋的人工孵化是现代家禽业生产经营过程中的关键环节,在家禽的繁殖和生产经营中具有相当重要的位置。高而稳定的孵化率是种鸡场、孵化场以及饲养者共同追求的目标。种蛋的孵化,主要是通过控制温度、相对湿度、通风换气、翻蛋等而实现的。其中,温度是最主要的因素,在种蛋孵化过程中,只有保证最适胚胎发育的温度,才能达到高而稳定的孵化率。适当的湿度也有利于孵化初期胚胎受热以及孵化后期胚胎散热和破     

我国禽蛋业的现状及发展对策

禽蛋富含蛋白质、脂肪、矿物质和维生素，是人们日常生活中具有很高营养价值的重要副食品之一。禽蛋生产在我国已有4000多年的历史，世界上许多国家优良品种的家禽都有中国家禽的血统。在禽类人工孵化方面，我国也是最早的国家之一。随着养禽业的发展，蛋品生产也得到了相应的发展。     

雏禽的小肠健康——确保有一个良好的开端

在现代家禽生产中,人工孵化的雏禽无法从与其父母的直接接触中受益。在自然情况下,家禽孵化的环境含有大量来自于禽蛋孵化者粪便中的共生微生物。这些细菌极易在刚孵出的雏禽肠道内定植,并有助于雏禽免疫系统的成熟和保护其免遭病原体的侵入。 本文将重点关注在家禽生命期的早期建立共生微生物菌群的重要性，并将列举多种情景以介绍病原菌能够通过消化系统侵入家禽体内的环境条件。     

《家禽饲养技术》大型系列片正在摄制过程中

《家禽饲养技术》是一部反映我国目前家禽饲养管理水平的大型系列录像片,全套系列片计划录制15小时。现已录制完成的有《鸡的人工授精》、《禽蛋的孵化》、《我国传统的禽蛋人工孵化技术》、《禽     

我国禽学学科发展现状及趋势

1 引言 禽学是研究利用现代科学理论来规范和改进家禽生产的各个技术环节,用现代经济管理方法科学地组织和管理家禽生产,实现家禽业内部的专业化和各个环节的社会化;合理利用家禽的种质资源和饲料资源,建立合理的家禽业生产结构和生态系统;不断提高劳动生产率、禽蛋和禽肉的产品率和商品率,使家禽生产实现高产、优质、低成本的目标,以满足社会对优质禽蛋和禽肉日益增长的需要的一门学科.     

第一季度蛋产品出口量减少

2007年第一季度，我国禽蛋生产形势良好，效益提高。据行业统计，第一季度家禽存栏48．7亿只，同比增长3．6％，禽蛋产量651．8万吨，同比增长1．9％。     

我国禽和蛋数量居世界之首

我国家禽存栏总数和禽蛋总产量连续七年居世界首位,人均占有禽蛋量达到世界人均水平。 截至1993年底,全国家禽存栏数达28亿多只,     

蛋的贮藏方法

随着养禽生产的发展,禽蛋的数量也正在增多,供销两旺。但由于家禽生理上的原因,一年四季产蛋并不均匀,严寒、酷热季节,蛋的生产下降,所以鲜蛋的生产有明显的季节性。在广东,一般以12月至翌年5月为产蛋旺季,约占全年产蛋量的60%;6—8月为     

蛋及蛋的保鲜方法

一、蛋的结构禽蛋是由蛋壳、蛋白、蛋黄三个主要部分组成,它们所占的比例,则因家禽的品种,蛋体的大小,产蛋季节等不同而不一样     

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。     

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。     

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。     

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。     

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.