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光照强度对北京鸭生产性能、胴体性能及肉品质的影响 总被引:3,自引:0,他引:3
本文旨在探究光照强度对北京鸭生产性能、胴体性能及肉品质的影响。选择600只1日龄健康的北京鸭,随机分配到5个组中,每组4个重复,每重复30只鸭(公母各占1/2)。试验光照强度各组分别设置为1、5、10、15和40 lx,白炽灯24 h全人工光照。试验期6周。结果表明:1)1~6周,各组间平均耗料量和平均体增重无显著差异(P0.05),5 lx组的料重比显著低于10、15、40 lx组(P0.05)。育雏期(1~2周)和生长期(3~5周)时各组生产性能无显著差异(P0.05),而肥育期(6周)时1 lx组的平均耗料量和平均体增重显著高于5、10、15 lx组(P0.05)。2)光照强度对屠体率、全净膛率、腿肌率、腹脂率及眼球指标(重量、横径和前后径)均无显著影响(P0.05),但5 lx组的胸肌率显著高于40 lx组(P0.05)。3)光照强度对最终p H(p Hu)、滴水损失率、黄度(b*)值的影响不显著(P0.05),40 lx组的最初p H(p Hi)显著高于5、10、15 lx组(P0.05),但亮度(L*)值显著低于5、10、15 lx组(P0.05)。15、40 lx组的红度(a*)值显著低于1 lx组(P0.05)。综上,5 lx光照强度不仅节能有效,还能提高北京鸭的饲料转化率和胸肌率。此外,低光照强度还有助于提高肉色的L*和a*值。 相似文献
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共轭亚油酸对北京油鸡肉品质及血清leptin和脂蛋白脂酶的影响 总被引:2,自引:1,他引:2
选用1日龄北京油鸡公雏360只,随机分成5个处理,每个处理6个重复,每个重复12只鸡,饲喂玉米豆粕型饲料基础日粮,添加0、0.25%、0.5%、1%、2%共轭亚油酸(CLA),用以研究CLA对北京油鸡脂类代谢和肉质性状的长期影响,试验期18周。结果表明:饲粮CLA提高了饲料利用率(P<0.05),显著性地降低了北京油鸡腹脂率和血清中脂蛋白脂酶(LPL)、leptin,显著增加了肌内脂肪的含量(P<0.05),但对pH值和肉色无显著性影响(P>0.05)。 相似文献
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《中国家禽》2019,(1)
为研究光照强度对"京红1号"蛋鸡产蛋性能的影响,随机选取同一饲养条件下,健康、体重接近一致的100日龄"京红1号"蛋鸡540只,随机分为3组,每组设3个重复,每个重复60只,3个试验组分别采用30 lx、20 lx、10 lx光照,测定高峰期产蛋性能和血液生化指标。结果显示:(1)光照强度30 lx组产蛋率达90%日龄为149.67日龄,比光照强度20 lx组提前7.33 d(P0.05),光照强度30 lx组和20 lx组,产蛋率达95%时的日龄无显著差异(P0.05),但比光照强度10 lx组分别提前6.00 d和7.00 d(P0.05);(2)在产蛋率90%和95%持续时间上,光照强度20 lx组分别为265.66 d和43.33 d,极显著高于光照强度30 lx组和光照强度10 lx组;(3)产蛋率90%时,光照强度30 lx组蛋重为53.92 g,比光照强度20 lx低2.08 g(P0.05),比光照强度10 lx组低2.44 g(P0.05),产蛋率95%时,光照强度30 lx组蛋重为57.80 g,比光照强度20 lx组低1.42 g(P0.05),比光照强度10 lx组低1.94 g(P0.05);(4)血液中GLU含量,光照强度30 lx组显著高于20 lx组和10 lx组(P0.05),血液中Ca2+含量,光照强度30 lx组显著低于20 lx组(P0.05),血液中P含量,光照强度30 lx组显著低于10 lx组(P0.05),AST、ALT、ALP、TP、ALB、TCHO、TG、LDL-C含量各试验组间差异均不显著(P0.05)。根据研究结果,推荐蛋鸡高峰期以光照强度20 lx为宜。 相似文献
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日粮代谢能水平对北京油鸡脂肪沉积和LPL基因表达的影响 总被引:3,自引:0,他引:3
试验旨在研究不同日粮代谢能水平对北京油鸡脂肪沉积及脂蛋白酯酶(LPL)基因mRNA表达影响。试验以3周龄北京油鸡公鸡为研究对象,将480只公鸡随机分为4组,分别饲喂4个代谢能水平的日粮(12.122、12.540、12.958和13.376 MJ/kg),每个处理组5个重复,每个重复24只鸡。试验期为10周。采用荧光定量PCR方法检测LPL基因mRNA表达水平。结果表明,日粮代谢能水平对鸡体脂沉积各项指标和LPL基因mRNA表达水平影响极显著,随日粮代谢能水平提高,各项体脂沉积指标极显著上升,胸肌和腿肌IMF、皮脂重和皮脂率在ME3达到峰值,LPL基因mRNA表达水平在ME2组达到峰值(P<0.01)。LPL基因mRNA表达水平与腹脂率、皮脂重和皮脂率呈显著正相关(P<0.05)。研究结果提示,日粮代谢能水平显著影响北京油鸡体脂沉积和LPL基因mRNA表达;LPL基因表达影响北京油鸡体脂沉积状况。 相似文献
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为研究复合益生菌对北京油鸡屠宰性能和肉品质的影响,采用2×3两因子析因试验设计,选择648只1日龄北京油鸡雏鸡随机分为3个处理,分别为对照组(基础饲粮)、抗生素组(基础饲粮中添加50 g/t杆菌肽锌)和益生菌组(基础饲粮中添加由产朊假丝酵母菌、枯草芽孢杆菌、嗜酸乳杆菌复合而成的复合益生菌,育雏期添加0.5 kg/t,育成期添加0.7 kg/t)。每个处理公母各半,每个性别9个重复,每个重复12只鸡,试验期为16周。正试期的第16周,从每个处理组的每个性别各随机选取9只北京油鸡进行屠宰,测定屠宰性能和肉品质。结果表明:各处理组北京油鸡屠宰率、半净膛率、全净膛率、胸肌率、腿肌率和腹脂率均无显著差异(P>0.05),胸肌和腿肌pH、肉色、滴水损失率、蒸煮损失率和剪切力也均无显著差异(P>0.05),且处理和性别也没有表现出显著的交互作用(P>0.05)。但复合益生菌和杆菌肽锌组北京油鸡胸肌粗脂肪含量较对照组分别降低了36.67%和28.81%,粗蛋白质含量分别提高了1.78%和2.00%。 相似文献
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《中国家禽》2017,(12)
试验研究了光照优化管理对半开放式垫料平养岭南黄鸡生产性能、抗氧化和抗应激功能的影响。将360只1日龄岭南黄公母混合雏随机分为2组,每组3个重复,每个重复60只。对照组采用24 h持续光照模式,光照强度为30 lx;试验组白天自然光照,夜间补光采用3D∶1L循环和强度10 lx的光照优化模式。试验为期50 d,分为1~21日龄和22~50日龄两阶段。在试验第50天,每个重复随机选取4只,共24只公鸡,空腹12 h后屠宰取样并检测相关指标。结果:(1)试验组较对照组有提高肉鸡日增重和饲料转化率的趋势(P0.05);(2)与对照组比,试验组血清褪黑激素浓度升高27.59%(P0.05),血清和肝脏总抗氧化能力和谷胱甘肽过氧化物酶活力显著提高(P0.05);(3)试验组相比于对照组血清皮质酮浓度明显降低(P0.05)。试验表明:在本试验条件下,光照优化管理能促进岭南黄鸡褪黑激素的分泌,增强抗氧化和抗应激功能,达到改善肉鸡生产性能的作用。 相似文献
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为了研究日粮能量与蛋白质水平对拜城油鸡生长期营养物质表观消化率的影响,试验选取270只8周龄拜城油鸡并随机分成9个处理组,每个处理组设3个重复,每个重复10只鸡.试验期共8周.试验组日粮根据生长阶段设计为8~11周龄:3个能量水平(11.70MJ/kg、12.12MJ/kg、12.54MJ/kg)、3个蛋白质水平(17... 相似文献
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试验旨在研究蒙脱石对北京油鸡蛋鸡生产性能、蛋品质和血清抗氧化指标的影响。选取体重相近、健康良好的180只22周龄的北京油鸡,随机分为5组,每组4个重复,每个重复9只鸡。对照组饲喂不添加蒙脱石的基础饲粮;试验组分别在基础饲粮中添加1‰、2‰、3‰、4‰蒙脱石。预试期7 d,正试期56 d。结果表明:添加蒙脱石对蛋鸡平均日采食量、产蛋率、平均日产蛋重等指标影响显著;与对照组相比,2‰蒙脱石组产蛋率和平均日产蛋重显著提高;1‰、2‰、3‰、4‰蒙脱石组的蛋重、蛋形指数、蛋壳色泽、蛋壳强度、蛋白高度、蛋壳厚度等蛋品质指标均无显著影响;与对照组相比,3‰、4‰蒙脱石组的血清总抗氧化能力显著降低,2‰、3‰蒙脱石组的总超氧化物歧化酶含量显著提高。由此可见,蒙脱石可以改善蛋鸡生产性能和血清抗氧化指标,在霉菌毒素不超标的情况下,北京油鸡饲粮推荐添加剂量为2‰。 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