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小肽对超早期断奶(SEW)仔猪生长表现的影响 总被引:1,自引:0,他引:1
仔猪超早期隔离断奶造成了所谓的“早期断奶综合症”,小肽营养素近几年来在动物营养尤其在超早期断奶仔猪中的应用优势逐渐引起了人们的关注,它能使仔猪肠绒毛长度增加、隐窝深度减小、各种消化酶活性显著增加、免疫系统更好地发育等优点,不失为一条解决“早期断奶仔猪综合症”的好途径。本文从小肽的吸收机制、营养作用等方面阐述了小肽对断奶仔猪生长表现的影响。 相似文献
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早期断奶仔猪的蛋白质营养研究 总被引:2,自引:0,他引:2
早期断奶是指区别于传统的28~35日龄或更大日龄断奶,一般称在21日龄以内断奶为早期断奶。新生仔猪能够充分利用乳中简单的碳水化合物、脂肪和蛋白质,但对于饲料中植物来源的大分子并不能很好的消化利用。此外,早期断奶尤其是超早期断奶的仔猪,消化机能不健全,消化系统尚未发育成熟,且受心理和环境等应激的影响,常表现出厌食或拒食、消化机能紊乱、腹泻、水肿、生长迟滞和饲料利用率低等所谓的“仔猪早期断奶综合征”。从而严重影响了养猪业的经济效益,这个问题迄今还没有得到彻底解决,其中导致仔猪早期断奶综合征的主要因素是营养应激。现就早期断奶仔猪的蛋白质营养研究进行综述。 相似文献
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早期断奶仔猪腹泻与营养调控 总被引:4,自引:0,他引:4
仔猪早期断奶技术是国内外集约化养猪生产中普遍关注的先进技术,可提高母猪的繁殖率,减少由母体向仔猪的疾病传播,并能提高生长期的生长性能和胴体品质。在养猪发达的国家和地区,已开始推广应用14日龄超早期断奶技术。但早期断奶仔猪受心理、环境和营养应激的影响,常常发生“仔猪早期断奶综合征”,表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等,其引发因素主要是营养应激,因此通过营养调控手段,根据仔猪生长发育的生理特点,配制适合仔猪的饲料来减少仔猪腹泻,是一条行之有效的途径。1早期断奶仔猪的消化生理早期断奶仔猪消化… 相似文献
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马美蓉 《上海畜牧兽医通讯》2003,(5):26-27
仔猪早期断奶是国内外集约化养猪生产中采用的一项先进的饲养管理技术之一 ,它能提高母猪的繁殖率 ,减少疾病由母体向仔猪传播机会。但仔猪断奶时易出现“仔猪早期断奶综合征”〔1〕:采食量下降、消化功能紊乱、腹泻、生长减缓以及饲料利用率降低等 ,究其原因主要是营养问题。因此 ,如何合理配制早期断奶仔猪料来预防早期断奶仔猪综合征 ,将具有十分重要的实践意义。1 早期断奶仔猪的营养需要1.1 能量与脂肪 :日粮能量是仔猪生长的重要限制因素 ,随着日粮能量浓度的增加 ,其生产性能得到明显改善(Taverner ,1989)。美国NRC(1994 )推荐体… 相似文献
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肽黄金配制仔猪早期断奶饲粮的饲养试验研究 总被引:1,自引:0,他引:1
选用价廉易得、品质优良的蛋白质原料配制适于仔猪早期断奶的饲粮是目前解决早期断奶仔猪营养问题的首要技术难题。肽黄金富含植物小肽,易为动物消化吸收,适合幼龄、病弱、应激等特殊生理状况下的动物使用。本研究用肽黄金作为重要蛋白源配制早期断奶仔猪抗应激饲粮进行饲养试验,旨在观测肽黄金对改善早期断奶仔猪生产性能的效果。 相似文献
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早期断奶仔猪的营养调控 总被引:9,自引:0,他引:9
在猪生产中,最关键的一环是仔猪生产,特别是早期断奶仔猪生产。仔猪早期断奶是国内外集约化养猪生产中普遍关注的先进技术,能提高母猪的繁殖率,减少由母体向仔猪的疾病传播,并能提高生长期的生产性能和胴体品质。目前养猪业发达国家已经开始推广应用14日龄超早期断奶技术。但仔猪早期断奶时受心理、环境和营养应激的影响,常表现为食欲差,消化功能紊乱、腹泻、生长迟滞、饲料利用率低等所谓的“仔猪早期断奶综合症”。引发的主要原因是营养应激。早期断奶仔猪的成活率和生产性能与猪品种、日粮养分、饲养管理、疾病防治等方面有关,… 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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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。 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