种蛋储存期对散养鸡孵化性能的影响研究

为了研究种蛋储存期对孵化性能的影响,试验以散养东北当地土鸡种蛋为研究对象,研究不同保存期(1～3 d、4～7 d、8～15 d和16～30 d)种蛋孵化性能的变化。结果表明:东北当地散养土鸡种蛋的最佳保存时间为7 d,种蛋保存时间在1～3 d和4～7 d之间的受精蛋孵化率变化不明显,保存超过7 d的种蛋受精蛋孵化率显著降低(P<0.05),且保存时间越长受精蛋孵化率越低;随着保存时间的延长,胚胎死亡率增高,保存1～15 d对胚胎早期死亡率影响不大,保存时间超过15 d会导致中后期死胚率增高。说明保存时间对种蛋孵化性能起关键性作用。     

贮存时间对乌蒙凤鸡种蛋孵化效果的影响

为提高乌蒙凤鸡种蛋孵化效果,提高养殖企业生产效益,试验收集43周龄乌蒙凤鸡种蛋18470枚分盘标记存放,按贮存时间分为5个试验组:Ⅰ组(贮存1~3 d)、Ⅱ组(贮存4~6 d)、Ⅲ组(贮存7~9 d)、Ⅳ组(贮存10~12 d)、Ⅴ组(贮存13~15 d),测定各组的孵化效果。结果:随着贮存时间延长,乌蒙凤鸡受精蛋孵化率、健雏率不断降低,死胚率不断增高。试验Ⅰ组、Ⅱ组受精蛋孵化率指标显著高于Ⅳ组(P<0.05),极显著高于Ⅴ组(P<0.01)。结论:乌蒙凤鸡种蛋贮存时间≤5 d孵化效果最佳。     

种蛋冬春季低温保存对孵化效果的影响

将28周龄农大3号父母代种鸡的商品代种蛋共870枚,随机分为6个试验组,每组120枚,1个对照组150枚。试验设计分别是:-15℃～-10℃贮存0.5小时和1小时;0℃贮存12小时和24小时;2℃～6℃贮存24小时和48小时;对照组为15℃贮存48小时,测验种蛋受精率、死精率、受精蛋孵化率、入孵蛋孵化率、健雏率、死胎率的影响。试验结果表明,种蛋在不同的低温条件下与正常温度条件下相比,受精率、死精率均无显著差异。在2℃～6℃贮存24小时条件下受精蛋孵化率下降和入孵蛋孵化率下降,受精蛋孵化率差异显著(P<0.05);入孵蛋孵化率差异极显著(P<0.01)。在-15℃～-10℃贮存1小时和在2℃～6℃贮存48小时条件下健雏率下降,差异极显著(P<0.01)。在-15℃～-10℃贮存1小时和在2℃～6℃贮存24小时条件下死胎率上升,差异显著(P<0.05)。     

孵化器开启风门时间对孵化率的影响

孵化器开启风门时间对孵化质量的影响试验使用28周龄农大3号父母代种鸡的种蛋共33600枚,放入两台相同的孵化器中各16800枚进行孵化。一台5d正常开启风门,一台10d开启风门,中间测定孵化箱内的CO2浓度。测定延期开风门对受精率、死精率、受精蛋孵化率、入孵蛋孵化率、健雏率、死胎率的影响。试验结果表明,种蛋孵化过程中10d开启风门,受精蛋孵化率和入孵蛋孵化率提高,差异极显著(P<0.01),健雏率上升,差异显著(P<0.05),受精率和早期死胚率无明显差异。     

保存温度、湿度和时间对鹌鹑种蛋孵化成绩的影响

本试验旨在研究鹌鹑种蛋适宜保存温度、湿度、时间及胚胎发育临界温度。采用单因素试验设计,按照蛋重均等原则分组,每组8个重复,每重复50枚;将2400枚种蛋均分为6组,保存温度分别为5、10、15、20、25、30℃;将2000枚种蛋均分为5组,保存湿度分别为40%、50%、60%、70%、80%;将1200枚种蛋均分为3组,保存时间分别为3、7、11 d,检测种蛋孵化率、健雏率等指标。将440枚种蛋均分为11组,保存温度在20~30℃内设置11个水平;将280枚种蛋均分为7组,保存温度在21.8~23℃内设置7个水平;每组40枚,保存5 d,每天每组取8枚测量胚盘直径。结果表明:从入孵蛋孵化率和受精蛋孵化率来看,保存温度15℃组最高,15、20、25℃组高于5、10、30℃组(P<0.05);保存湿度70%组高于40%、80%组(P<0.05),保存3、7 d组高于保存11 d组(P<0.01)。此外,保存温度≥23℃胚盘直径极显著增大。由此可知,鹌鹑种蛋最佳保存温度15℃,适宜范围15~20℃;最佳保存湿度70%,适宜范围为65%~70%;适宜保存时间为3~7 d;胚胎发育临界温度为23.0℃。     

短时孵化对种蛋孵化时间及成绩的影响

为研究AA+肉种鸡种蛋在长期存蛋的情况下,利用短时孵化操作规程看其对孵化成绩的影响。本研究选取36周龄父母代AA种鸡种蛋7560枚(45串),为同一批次种蛋,每组2520枚(15串)种蛋,分为3组。储存时间分别为第Ⅰ组3～4d;第Ⅱ组12～14d(进行短时孵化操作);第Ⅲ组12～14d,其他储存条件相同。孵化后对其捡雏时间、受精率、死胎率、毛蛋率、残死率、受精蛋孵化率、受精蛋A雏率、受精蛋健雏率(包括AB雏)等孵化指标进行两两分析,结果显示:(1)第Ⅰ、Ⅲ组比较可以看出,第Ⅲ在保存时间上的处理结果明显差于第Ⅰ组,即存放时间为12～14d种蛋的孵化结果明显差于存放时间3～4d的种蛋,具体表现为存放时间长的种蛋,捡雏时间长4h、死胎率升高1.9%、毛蛋率略高、残死率一致、受精蛋孵化率低3.7%、受精蛋A雏率低4.3%、受精率蛋健雏率低2.3%;(2)第Ⅱ、Ⅲ组比较可以看出,第Ⅱ组检雏时间短1h、死胎率低于第Ⅲ组1.9%、毛蛋率略低、残死率略高、受精蛋孵化率高于第Ⅲ组3%、受精蛋A雏率高于第Ⅲ组2.8%、受精率蛋健雏率高于第Ⅲ组2.4%;(3)第Ⅰ、Ⅱ组比较可以看出,第Ⅱ组捡雏时间长3h、受精蛋孵化率低于第Ⅰ组0.7%、受精蛋A雏率低于第Ⅰ组1.5%、受精率蛋健雏率高于第Ⅰ组0.1%、毛蛋率略低于第Ⅰ组,残死率略高于第Ⅰ组、死胎率一致。研究结果表明,对储存时间超过10d以上的种蛋进行短时孵化操作,可有效的保持种蛋的孵化成绩,对孵化场技术管理具有实际的指导作用。     

大角度翻蛋孵化机的研制及其在鹅种蛋孵化中的应用

针对鹅种蛋设计的新颖大翻蛋角度孵化机,使得种蛋孵化过程翻蛋角度由常规的90°提高到170°左右,并附加其他温湿度及凉蛋控制等技术,对胚蛋更好通风换气。利用大角度翻蛋和常规90°角孵化机孵化扬州鹅、马岗鹅和狮头鹅种蛋,比较对活胚率、孵化率、受精蛋孵化率和弱雏率之间的影响。新颖大角度翻蛋孵化机使扬州鹅种蛋7日胚龄活胚率、15日胚龄活胚率、孵化率和受精蛋孵化率分别提高2.70个百分点(P0.01)、3.31个百分点(P0.05)、3.55个百分点(P0.05)和1.71个百分点(P0.01)。对马岗鹅种蛋7日胚龄活胚率、15日胚龄活胚率、孵化率和受精蛋孵化率无显著影响(P0.05),但较常规孵化机能弱雏率降低1.54个百分点(P0.05)。对于大体型狮头鹅的种蛋,入孵蛋孵化率和受精蛋孵化率分别提高6.11个百分点(P0.05)和7.34个百分点(P0.01),并降低弱雏率2.08个百分点(P0.05)。采用大角度翻蛋孵化机可提高扬州鹅种鹅生产净利润10.3%、狮头鹅种鹅生产净利润16.2%,尤其能提高种鹅反季节繁殖生产的经济效益。     

籽鹅种蛋蛋重与蛋形指数对孵化效果影响的研究

本试验旨在研究不同水平蛋重与蛋形指数对籽鹅种蛋孵化效果的影响,进而总结出种蛋筛选的最佳方案,为籽鹅个体、家系种蛋的选留及籽鹅的繁衍、孵化、生产提供科学参考。选取二年籽鹅种蛋2 469枚,蛋重为94.8~154.4 g,平均蛋重（123.3±9.5）g;蛋形指数为1.24~1.63,平均蛋形指数1.45±0.05。采用2因素4水平试验设计,将所有种蛋按蛋重与蛋形指数分成16个孵化组（蛋重与蛋形指数分别分为4个水平）,测量每枚种蛋蛋重与蛋形指数,并在蛋壳上做好编号,在相同孵化条件、同一孵化设备中进行两次孵化试验。结果表明,①蛋重<118.0 g组种蛋受精率最高,>131.9 g组次之;>131.9 g组种蛋受精蛋孵化率最高,125.0~131.9 g组次之,且受精蛋孵化率随着蛋重增大升高;125.0~131.9 g组种蛋孵化健雏率最高,>131.9 g组次之;>131.9 g组种蛋孵出鹅雏出生重最大。②蛋形指数在1.47~1.51组种蛋受精率及种蛋孵化健雏率最高,>1.51组次之;1.47~1.51组种蛋受精蛋孵化率最高,1.42~1.46组次之。分析以上结果可得出：籽鹅种蛋蛋重对种蛋受精率、受精蛋孵化率、健雏率、鹅雏出生重有显著影响（P<0.05）,以籽鹅蛋重在125.0~154.4 g为宜;蛋形指数对种蛋受精率、受精蛋孵化率、健雏率亦有显著影响（P<0.05）,对种蛋孵出鹅雏出生重无影响（P>0.05）,以蛋形指数在1.47~1.51为宜。籽鹅种蛋蛋重与蛋形指数对受精率、受精蛋孵化率、健雏率、鹅雏出生重的影响均存在交互作用。其中,蛋形指数对种蛋孵化健雏率的影响较蛋重强,其作为单一因素对鹅雏出生重无影响。以上结果表明,以蛋重或蛋形指数任一因素作为种蛋筛选的依据都不科学,应综合考虑以达到种蛋优选的目的。     

籽鹅种蛋机摊结合孵化技术的研究

以籽鹅种蛋为研究对象,在种蛋孵化至20、24、27胚龄时,随机选取部分种蛋,从孵化器移至摊床继续进行孵化直至出雏完毕。比较上摊孵化与全程机器孵化的效果,并研究最佳的上摊胚龄。通过试验证明,籽鹅机器孵化的受精蛋孵化率平均为85.84%,上摊孵化的受精蛋孵化率平均为89.23%,提高3.39个百分点(P<0.05)。籽鹅在20,24,27胚龄上摊的受精蛋孵化率分别为87.41%、91.03%、89.19%(P>0.05),可见机器孵化鹅胚蛋至24胚龄时上摊孵化效果最好。     

朝鲜鹌鹑种蛋重和蛋形指数对孵化效果的影响

选取288枚朝鲜鹌鹑种蛋,按蛋重、蛋形指数大小各分为3组,在相同条件下孵化,研究蛋重和蛋形指数对孵化效果的影响。试验结果表明:蛋重、蛋形指数对受精蛋孵化率的影响均极显著(P<0.01)。蛋形指数对健雏率的影响显著(P<0.05),蛋重对健雏率的影响不显著(P>0.05)。     

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。     

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。     

獭兔睾丸的组织学观察

家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1　材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5～ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2　结果和讨论2 .1　睾丸定量组织学指标的测定结果　见表 1。表 1　獭兔睾丸定量组织学指标　　　μm,个 /精细管60日龄 75日龄 90日龄曲细精管…     

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。     

Observations of fracture of the anconeal process of the ulna of swine

Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a "tight," restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a "buttress callus" which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process.     

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.     

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.