影响猪人工输精产仔数因素分析

本文论述了不同精子数输精产仔数的影响,不同间隔输精时间对产仔数的影响,不同配种年龄对产仔数的影响,情次对受胎率的影响,母猪胎盘效率对产仔的影响,饲料的原因,疫苗接种时间不合理,疫病的影响品种的影响,季节变化的影响,环境温度对母猪产仔数的影响,遗传因素的影响外源性刺激对产仔数的影响对产仔数的影响及其对策。     

纳氏试剂分光光度法测定氨氮的影响因素及消除

纳氏试剂分光光度法测定水质中氨氮,受很多因素的影响,主要有水样自身干扰物质的影响,环境条件的影响,药品试剂的影响,时间的影响等诸多因素的影响,本文针对此种情况进行分析总结。     

全球增温变化对植物的影响

从全球增温变化对植物影响的分析,阐述温度对全球植物群落的影响,包括对植物群落分布的影响,物种多样性的影响,以及对群落中物种个体的影响。     

电子商务对会计的影响

本文探讨了电子商务对会计理论和会计结算的影响,其中包括电子商务对会计主体假设的影响,对货币计量假设的影响,对持续经营假设的影响,对会计分期假设的影响等。本文也阐述了电子商务对会计要素和会计原则的影响和对内部控制的影响。以及讨论了电子商务对会计报告的影响。本文也对电子商务对会计的挑战进行了分析。     

论草原生态保护与经济效益获取平衡的影响因素

在简要介绍草原生态保护与效益获取模式的基础上,论述了影响草原生态保护与经济效益获取平衡的因素,包括自然资源的影响、草原地表获取商品状况的影响、天然草原外部因素的影响、管理制度的影响、资本投入的影响和文化、信仰与人口状况的影响。     

浅析影响缉毒犬训练使用的几个因素

影响缉毒犬训练使用的因素很多,而单兵作战和团队合作时的影响因素又有所不同。单兵作战时,主要是一些自然因素和训导员自身的影响,团队合作时,主要是战术运用对缉毒犬的影响。一、单兵作战时的影响因素单兵作战时,主要从气流、环境、牵引带、犬舍、日常饲养等方面考虑,训导员自身是活动的主体,是各种因素的影响者。(一)室外气流对毒品气味扩散的影响气流影响毒品气味扩散的方向、速度和范围。气流对毒品气味的影响呈锥体,毒品源就是气味锥     

猪抗病力的影响因素——营养

猪机体营养对抗病力的影响包括影响机体免疫系统发育与功能、影响肠道发育与健康、影响传染性疾病的发生发展、影响抗病基因的表达、缓解霉菌毒素的危害等方面。因此,猪的营养状况影响着机体的免疫功能和对疾病的抵抗力,而机体的健康状况又影响着猪的营养需要。     

哈白猪生长发育的研究——(二)饲养条件和杂交对生长发育的响影

通过两次试骏比较不同饲养条件对猪的生长发育的影响;利用哈白猪及其杂种(75％苏白)的资料,说明杂交对猪生长发育的影响。在我们的试验条件下,饲养条件不论对整个机体的体重或对内部组织或器官的影响都大大超过了杂交的影响。饲养条件对组织或器官影响的大小与其发育早晚成反比,即愈早熟的组织或器官所受的影响愈小,愈晚熟者所受的影响愈大。如脂肪、肌肉所受的影响为最大,骨骼及其他内部器官所受的影响则较小。同一影响条件对机体或内部组织器官的影响是不平衡的。如对腰部的影响远大于腿臀部。外界因素对机体影响的不平衡性,又表现在同一作用条件下对各组织或器官影响显著的时期并不一致。如对大肠影响比较显著的时期为6—12个月龄,胃为四个月龄。哈白猪经苏白猪连续杂交两代后,除个别组织器官外,在我们的试验条件下,一般差异不够明显。饲养、杂交条件对各组织或器官生长强度的影响,一般来说,不能改变生长强度曲线变化总的趋势,只会影响到生长强度的大小,即曲线的高低。     

违法违规调运生猪的原因分析与综合治理对策

本文分析了违法违规调运生猪行为发生的原因:疫情影响、产能影响、季节影响、产销方式影响、利益驱动影响、监管能力及水平的影响;提出了综合治理对策:促进产能尽快恢复,转变生产经营方式,提升全链条监管能力和水平。     

抗生素添加剂的功用和机制

抗生素促进畜禽生长,至少有三种作用:(1)影响代谢;(2)节约养分;(3)抑制疾病。一、影响代谢对代谢的影响首先应归功于控制疾病的作用,因为全身性感染无疑会影响代谢率。现已证实,抗生素能影响畜禽的代谢反应。Brand和Johnson(1953)报道,金霉素能影响水和氮的排泄,能影响猪的代谢率。Broby等(1954)用大白鼠肝匀浆     

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.