如何控制母鸡性成熟

一般情况下,产蛋鸡在18～20周龄见蛋,21～22周龄产蛋率达5%,23～24周龄产蛋率达50%,27～28周龄达90%以上。为了让蛋鸡有较好的产蛋率和维持比较长的产蛋高峰期,必须要让鸡的体重达标,即褐壳蛋鸡80%以上体重达到1500克,白壳蛋鸡     

畜牧业技术推广项目系列报道之九农业部重点推广的畜牧业技术项目简介

海兰W -36白壳蛋鸡海兰白壳蛋鸡 (HY -LINEVARIETYW -36)是美国海兰国际公司 (HY -LINEINTER NATIONAL)培育的四系配套优良蛋鸡品种 ,我国从20世纪80年代开始引进 ,目前在全国有多个祖代或父母代种鸡场 ,是白壳蛋鸡中饲养较多的品种之一。海兰白壳蛋鸡具有饲料报酬高、产蛋多和成活率高的优良特点。海兰白壳蛋鸡商品代生产性能 :1～18周龄成活率97 %～98 % ,体重1.28千克 ,只鸡耗料量5.66千克 ;产蛋期 (至80周 )高峰产蛋率93 %～94 % ,出雏至50 %产蛋率的天数为155天。入舍母鸡年产蛋数 :60周龄为230～237枚 ,80周龄为330～33…     

肉种鸡称重技术与应用

肉种鸡称重技术与应用孙文福，褚金忠，徐全平（山东省广饶县种鸡场２５７３００）在肉种鸡的生长过程中，为了正确地了解种鸡的生长发育情况，检验限饲的效果，从雏鸡３周龄开始，每周末鸡群抽样５～１０％，进行个体称重，一直到产蛋高峰前，产蛋高峰后每４周称重一次．...     

蛋鸡开产前后饲养管理

蛋鸡开产前后是指开产前三周至产蛋率达50%左右这段时间，一般为18～24周龄。这段时期，青年鸡由育成舍转入产蛋鸡舍，饲养管理与环境因素都有所改变，因此这阶段饲养管理水平，直接影响到蛋鸡开产日龄的迟早和以后产蛋率的高低。 1　转群准备 1.1　测定体重 　　在15～16周龄时，要测定青年鸡的体重，看测定的体重是否达到该品种的标准体重，或者在以后的1～2周饲养下，能达到本品种的标准体重。     

惠州麻肉种鸡的强制换羽探讨

将1210只健康的53周龄的广东惠州麻肉种鸡用于强制换羽。试验前测定标记鸡的体重,共停料18天,自由饮水,自然光照。停料第2周每隔1天测定一次体重,当失重率达到27.44%时恢复喂料。恢复喂料后18天见蛋,经过5周产蛋率就达到57.14%,9周时产蛋率77.67%。结果表明,优质肉种鸡停料后体重下降速率低于蛋用鸡;种鸡进行强制换羽期间不停止饮水供应能够有效减少鸡只的死亡率;合理把握恢复喂料时机,能够使鸡群换羽后保持良好的产蛋性能。     

延长蛋用鸡产蛋高峰期的技术

<正>蛋鸡产蛋具有一定的规律性,一般18～21周龄开产,开产后3～4周产蛋率达到50%,6～7周达到90%以上(高峰期)。高峰期维持一般为3～6个月,产蛋量与蛋鸡品种、开产时体质以及产蛋期的饲养管理条件密切相关。本文介绍延长蛋用鸡产蛋高峰期的技术措施。1加强育成期饲养管理,培育优秀青年母鸡(1)控制鸡只体重。优良种鸡都有标准体重,在饲养过程中     

优质肉种鸡强制换羽效果分析

将1210只健康的53周龄的广东惠州麻肉种鸡用于强制换羽。试验前测定标记鸡的体重,共停料18d,自由饮水,自然光照。停料第2周每隔1d测定一次体重,当失重率达到27.44%时,恢复喂料。恢复喂料后18d见蛋,经过5周产蛋率就达到57.14%,9周时产蛋率77.67%。结果表明,优质肉种鸡停料后体重下降速度低于蛋用鸡;种鸡进行强制换羽期间不停止饮水供应,能够有效减少鸡只的死亡率;合理把握恢复喂料时机,能够使鸡群换羽后保持良好的产蛋性能。     

淘汰母鸡体重过小的原因及解决措施

产蛋母鸡饲养至72～78周龄淘汰作为肉用。不同品种母鸡淘汰时的体重标准不同,如来航鸡78周龄体重是1.8千克,而海兰褐鸡体重是2.25千克。淘汰时的体重大小不仅影响淘汰鸡的价值,也可间接反映鸡在产蛋期的生产性能。     

评估肉用种鸡

对于种鸡场的管理人员来说，如何评估肉用种鸡、监测数据是否准确、鸡群每日饲喂多少料量、何时转群、每百只母鸡配给多少公鸡，这些信息对一个种鸡群的成功与否起着至关重要的作用。业内大多数同行都认同，管理种鸡群最重要的一项指标就是鸡群的平均体重，或者说，鸡群对喂料水平的反馈。１如何对种鸡进行称重肉种鸡的个体称重应越早越好，最好从第２周龄开始。对某些称重器来说，鸡只只有达到２２０～３００g时才能有效地使用。早一些对鸡只进行称重可以确定所饲养的鸡群属于哪种类型。年轻种鸡群所产的雏鸡势必比产蛋中期或产蛋后期所产…     

科普园地

品种推荐1海赛克斯褐由荷兰优利布里德公司培育的4系配套杂交鸡。其生产性能如下育成期成活率:97%0～20周龄耗料:7.2kg18周龄体重:1.4kg78周龄体重:2.25kg产蛋率达50%时的日龄:158d78周龄产蛋数:302枚平均蛋重:63.6g2迪卡黄金褐由美国迪卡家禽公司培育的杂交鸡。该鸡具有早熟、耐高温、适应性强等特点。商品代性能如下育成期成活率:96%～98%产蛋期成活率:94%～96%18周龄体重:1.70～1.78kg40周龄体重:2.05kg产蛋率达50%日龄:140d高峰期产蛋率:92%～95%72周龄入舍鸡产蛋数:290～310枚78周龄入舍鸡产蛋数:330～340枚18～78周龄平均蛋重:63～64.…     

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.     

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。