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仔猪初生重对断奶窝重的影响 总被引:1,自引:0,他引:1
提高猪的增重速度首先要从仔猪初生重、断奶重抓起 ,要取得仔猪窝重高的结果 ,除了抓好泌乳母猪的饲养管理、发挥母猪良好的泌乳性能外 ,做好仔猪补料、抓旺食、过好断奶关及疾病的预防工作是关键。1 试验材料与方法1 .1 试验猪随机选用 1 8窝“杜长上”初生仔猪 ,饲养 3 5日龄断奶。泌乳母猪、仔猪分别用申兰集团饲料厂生产的泌乳母猪料和乳猪料。母猪产前一周进产房待产 ,母猪采用高床单体限位栏 ,两侧为仔猪活动空间并配有保暖小间。1 .2 试验猪的饲养管理1 .2 .1 对临产前母猪后躯、乳房部位及分娩床面用0 .1 %高锰酸钾溶液擦拭消毒… 相似文献
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影响绒山羊初生重和断奶重的固定效应分析 总被引:1,自引:0,他引:1
影响绒山羊初生重和断奶重的固定效应分析张文生,方展欢(北京市农林科学院畜牧兽医研究所100081)前言我国绒山羊大都在草场较差,气候条件严酷的环*境中放牧生产,幼龄羔羊的生长发育不仅关系到其未*来的生产性能,而且决定着其是否能渡过第一个冬春*枯草期。... 相似文献
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影响猪场生产指标和经济效益的主要因素是仔猪成活率,其与仔猪初生重及断奶重密切相关,因此探究仔猪初生重及断奶重与成活率之间的关系,对猪场淘汰仔猪具有参考价值。本研究以四川阆中大北农桥楼猪场二元母猪所产500头仔猪为试验对象,记录、整理和分析仔猪初生重、21日龄断奶重、21日龄成活率及70日龄成活率。结果表明:仔猪初生重呈正态分布,体重过小、过大的数量较少;体重≤1.0kg的仔猪21日龄成活率较低,体重>1.3kg的仔猪21日龄成活率均在95%以上;21日龄断奶重较大仔猪的70日龄成活率较高,5.5~6.0kg的仔猪最为理想。因此,建议四川阆中大北农桥楼猪场适当淘汰初生重≤1.0kg的仔猪,提高经济效益。 相似文献
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仔猪初生重对21日龄断奶重的影响 总被引:2,自引:0,他引:2
《当代畜牧》2007,(12)
研究初生重对21日龄断奶重的影响。做了两个重复试验,共统计了655头仔猪,每个试验根据初生重分为4个阶段(0.70~1.00,1.10~1.30,1.31~1.60,1.61~2.10)。结果表明,初生重在1.3kg以下,21日龄重达不到平均重。初生重在1.3kg以上,21日龄重超过平均重。 相似文献
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肉用鸡入孵蛋重,初雏重与其生长速度的关系 总被引:1,自引:1,他引:0
1 试验材料和方法 1.1 材料 选取48周龄艾维茵父母代种鸡所产蛋580枚及其孵化后的鸡雏300只。 1.2 方法 试验用蛋根据不同的重量范围,分成对照组及A、B、C、D、E试验组共6组,各组分别编号、装蛋,在同一条件下进行孵化。记录入孵蛋重及相应的初雏重和各试验组平均重。 试验用雏从上述相应蛋重组所孵雏中得到,各组随机选取50只(剔除劣雏)。按原分组在相同饲养管理下进行对比饲养,定期称重,记录个体重、出栏重及相应的平均体重。 相似文献
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养好仔猪 ,力争全活健壮 ,使同窝仔猪发育整齐 ,获得较理想的增重 ,可以采取以下措施。1 提高仔猪初生重俗话说 :“初生重差一两 ,断奶重差一斤 ;断奶重差一斤 ,出栏重差 10斤”。仔猪初生体重的大小 ,直接影响断奶窝重的高低。优良母猪是提高仔猪初生重的关键 ,选择体型高大、四肢粗壮、臀部发育好、奶头多又匀、护仔性强、泌乳性能好的母猪 ,进行科学饲养和配种 ,这样才能达到产仔多 ,成活率高 ,断奶窝重大的目的。在怀孕母猪的饲养管理中 ,母猪怀孕前期饲养水平可低一些 ,怀孕前 80d可多喂青饲料 ,适当减少精料比例。这样既不影响产仔 … 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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。 相似文献
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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。 相似文献
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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. 相似文献
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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. 相似文献
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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. 相似文献