蛋壳厚度与孵化率

<正>蛋壳在孵化中发挥着一个重要作用,而孵化是影响家禽生产效益的最重要因素之一。蛋壳厚度有多种不同的测量方法。最常见的测量方法是用厚度测量仪测定含或不含壳膜的蛋壳厚度,但此方法并不足以反应蛋壳厚度对孵化率的影响。因此,研究人员通过和蛋壳厚度紧密相关的蛋比重评价了蛋壳厚度,或用蛋重的对数来估算蛋壳厚度。然而,所有这些方法都是间接地对蛋壳厚度进行评估。     

家禽蛋内壳膜厚度的组织学测定

本文利用组织学方法测定了鸡、鸭、鹅、家鸽和鹌鹑五种家禽蛋内壳膜（内、外膜）的厚度，其顺序为：鹅＞鸭＞鹌鹑＞家鸽，其蛋壳膜厚度与蛋白与蛋的大小及蛋壳强度存在着一定的相关。     

不同钙源对种鸭产蛋后期产蛋率及蛋品质的影响观察

产蛋率是衡量种禽生产性能的主要指标.由于机体生理功能的转变,加上营养、疾病等的综合影响,进入产蛋后期的种鸭,产蛋率明显降低,而且蛋的破损率提高.影响种鸭生产性能以及蛋壳质量的因素主要有非营养因素和营养因素两大类[1-5],其中钙是决定蛋壳质量的主要因素,钙缺乏会导致蛋壳厚度和强度降低,产软壳蛋、沙壳蛋甚至无壳蛋且产蛋率下降.     

蛋（种）鸭产蛋下降综合征的防治

蛋（种）鸭产蛋下降综合征是指蛋鸭养殖生产中出现的以产蛋数量下降、产异常蛋（软壳蛋、畸形蛋、大小不均、蛋壳形状异常等）、无产蛋高峰或持续低产蛋率的产蛋现象，也称种（蛋）鸭产蛋异常。给蛋鸭养殖生产造成巨大经济损失，须引起养殖户高度重视。     

莆田黑鸭蛋壳颜色对孵化失重的影响

为了探测不同蛋壳颜色鸭蛋对孵化失重的影响,选取莆田黑鸭种蛋500枚进行孵化,将试验种蛋分为白壳蛋组和青壳蛋组,通过测定各胚龄重,计算孵化失重和失重率,分析莆田黑鸭白壳蛋和青壳蛋孵化失重是否存在差异。结果表明,在6胚龄、12胚龄、18胚龄莆田黑鸭白壳蛋组和青壳蛋组的孵化失重(率)之间无显著性差异(P>0.05),而24胚龄和27胚龄,白壳蛋组和青壳蛋组孵化失重(率)差异达到显著水平(P<0.05),表明了莆田黑鸭蛋壳颜色对孵化失重有一定的影响,白壳蛋在孵化后期失重(率)大于青壳蛋。     

蛋种鸡产蛋期不同阶段对种蛋孵化性能的影响

鸡在一个产蛋周期中,蛋的大小、蛋壳强度和蛋品质都随着产蛋期而变化,这标志着鸡生殖生理在产蛋期间发生了某些变化.为研究这些变化对孵化效果的影响,人们从蛋重、蛋形、蛋壳品质等方面对孵化的影响开展研究[1～4],并提出了合格种蛋的要求[5].然而,即使合格种蛋,在产蛋期的不同阶段其蛋重、蛋壳质量及蛋内容物成分含量也有明显差别.我们根据产蛋期不同阶段种蛋的特点,对不同产蛋阶段种蛋的适宜孵化条件进行探索,并期望应用于规模化孵化生产.     

樱桃谷鸭父母代种蛋大小与孵化率的关系

家禽的孵化是一个很复杂的生物质变过程，在这个过程中要受到许多因素的直接或间接的影响，如遗传、种禽饲养、种 蛋品质、孵化环境条件等等。而本文就樱桃谷肉用种鸭父母代种蛋大小与孵化率的关系做试验如下： 　　一 .材料与方法 　　1.种蛋的选择：取我场 1999年 2月 24日从四川绵英公司引进樱桃谷肉用种鸭父母代种蛋，挑选新鲜、清洁无污染、无裂缝、形状符合标准的种蛋 2898个，按其蛋重分成 5个等级，并在蛋盘上贴上标签。 　　2.孵化方法：采用常规孵化程序，即温度、相对湿度、 1－ 5天， 38.20℃、 70％； 6－ 11天， 37.9℃、 6…     

家禽种蛋贮存四注意

自繁自孵自育家禽,是一项致富门路,但种蛋贮存的好坏,对能否孵化出优质苗禽影响很大。因此,在贮存家禽种蛋时,要注意以下四点: 一、蛋壳表面如果粘有禽粪等污物,不要擦拭和水洗。因为蛋壳表面有一层胶膜,能够防止微生物侵入蛋内,如果擦拭或水洗,就破坏了壳胶膜,蛋很容易变质。     

霉菌毒素对蛋壳质量的影响

好的蛋壳质量是保护鸡胚生命的基础,蛋壳质量差的鸡蛋既不能作为生鲜蛋摆上餐桌,也不能作为孵化蛋来使用,因此造成了严重的经济损失。蛋鸡饲料中的霉菌毒素是导致蛋壳质量严重下降的因素之一。笔者综述了多种霉菌毒素对家禽蛋壳质量的影响,并且讨论了在实际生产中降低霉菌毒素对蛋壳质量影响的方法。     

北京鸭蛋的机器孵化(摘要)

笔者从1985年以来结合教育实验实习从事北京鸭蛋和樱桃谷鸭蛋的机器孵化工作,约孵了几十万蛋,有如下经验体会: 1、种鸭的年龄、营养和健康情况,以及蛋的大小、蛋形,蛋壳质量、蛋壳清洁与否等对孵化成绩都有影响。季节也有影响,而以夏季的较低,这种情况,南方北方都是如此。 2、种蛋的贮存,一周以内以15℃温度,75—80％相对湿度为宜。一周以上以10℃,     

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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。 …