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选用停产后重新开产前的金定鸭90只，研究日粮中添加不同水平吡啶羧酸铬对重产蛋鸭生产性能的影响。日粮中添加铬水平分别为0、100、200、400、800μg／kg。试验期为6周。结果表明，日粮中添加吡啶羧酸铬200μg／kg和400μg／kg有促进重产蛋鸭早期开产的趋势，提高产蛋率、平均蛋重和蛋壳品质。重产蛋鸭日粮适宜铬水平200-400μg／kg，过高或过低的铬水平均不能发挥重产蛋鸭的最佳地生产性能。 相似文献
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试验旨在研究能量与吡啶羧酸铬的互作效应对肥育猪肉质性状的影响。选择体重60 kg左右,杜×长×大三元杂交肥育猪36头,分为4组,分别饲喂低能日粮、低能+吡啶羧酸铬日粮、高能日粮、高能+吡啶羧酸铬日粮进行试验,对肥育猪背最长肌的肉色、pH值(屠宰后24 h)、大理石花纹、肌内脂肪(intramuscular fatI,MF)含量、剪切力、滴水损失、熟肉率、肌肉糖原含量指标进行测定。结果表明:①能量水平对肉色评分、滴水损失有极显著的影响(P<0.01);②能量水平对肌内脂肪(IMF)有显著影响(P<0.05);③能量水平对pH值、大理石花纹、剪切力、熟肉率、肌糖原含量均无显著影响(P>0.05);④添加吡啶羧酸铬对肉色评分、pH值I、MF、大理石花纹、滴水损失有极显著的影响(P<0.01);⑤添加吡啶羧酸铬对熟肉率、肌糖原含量有显著影响(P<0.05);⑥添加吡啶羧酸铬对剪切力无显著影响(P>0.05);⑦能量与吡啶羧酸铬互作对大理石花纹、熟肉率有显著影响(P<0.05);对其他肉质性状均无显著影响(P>0.05);⑧在低能日粮中添加200μg/kg吡啶羧酸铬,提高了肉色评分p、H值I、MF含量、大理石花纹和熟肉率;并降低了肌糖原含量。综上所述,在育肥后期采用低日粮能量水平并添加200μg/kg吡啶羧酸铬可改善肉质。 相似文献
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不同来源有机铬对断奶仔猪生产性能影响的研究 总被引：1，自引：0，他引：1
试验采用单因子完全随机设计,选取28日龄断奶纯种大白仔猪128头,按体重接近随机分为4个处理组,每组4个重复,每个重复8头仔猪,公母各半。处理1为基础日粮(对照组),处理2为基础日粮+酵母铬200μg/kg(以Cr元素计),处理3为基础日粮+吡啶羧酸铬200μg/kg(以Cr元素计),处理4为基础日粮+甲基吡啶铬200μg/kg(以Cr元素计),试验期5周。试验结果表明:日粮中添加有机铬能提高仔猪的采食量、日增重,降低料肉比、腹泻率,各处理组均好于对照组,仅对照组与处理组2在采食量方面差异显著(P0.05),其它处理组差异均不显著(P0.05)。酵母铬在提高采食量和生长速度方面优于吡啶羧酸铬、甲基吡啶铬;但吡啶羧酸铬在降低料肉比方面较酵母铬和甲基吡啶铬好。日粮中添加有机铬能降低血清中尿素氮和葡萄糖水平,能促进仔猪体蛋白质的合成和采食。 相似文献
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高温下日粮铬水平对肉鸡生长性能和血液生化指标的影响 总被引：7，自引：0，他引：7
试验1 :选用72只体重接近的28日龄肉鸡随机分成4组 ,各组铬的添加量分别为0、200、400、600μg/kg(以吡啶羧酸铬形式) ,试鸡饲养于人工气候舱中 ,舱温为25～33℃ ,试验期2周。试验结果表明 :1.日粮中添加600μg/kg 的铬 ,与对照组相比 ,42日龄肉鸡体重提高10.7 %(P<0.05) ,日增重提高13.7 %(P<0.05) ,而对日采食量、饲料转化率无显著影响。2.日粮补铬对血清T3、T4、葡萄糖、甘油三酯、胆固醇含量没有显著影响 ,而使血清总蛋白水平升高 ,尿素氮水平下降(P<0.05)。试验2 :选用500只体重接近的21日龄肉鸡随机分成5组 ,铬添加量分别为0、200、400、600和800μg/kg(以吡啶羧酸铬形式) ,试鸡饲养于夏季鸡舍中 ,日温度在30～35℃之间 ,试验期5周。试验结果表明 ,日粮中添加Cr800μg/kg,使56日龄肉鸡体重、日增重、饲料转化率分别提高7.5 %、11.9 %、6.2 % ,但都不显著 ,表明给饲养于高温条件(30～35℃)下肉鸡补铬有提高增重和饲料转化率的趋势。 相似文献
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选用144只1日龄体重均匀、健康的艾维茵肉仔鸡,随机分成6个日粮处理组:1组为对照组,喂基础日粮;2～6组为试验组,分别在基础日粮中添加0.5mg/kg、1mg/kg、1.5mg/kg、2mg/kg、2.5mg/kg铬(以吡啶羧酸铬形式),研究在日粮中添加不同浓度的吡啶羧酸铬对肉仔鸡生产性能的影响.试验结果表明:①日粮中添加铬浓度为0.5～1mg/kg的吡啶羧酸铬时,能显著提高肉仔鸡增重,明显改善肉仔鸡的饲料效率(P＜0.05);②日粮中添加铬(吡啶羧酸铬形式)能够提高经济效益. 相似文献
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吡啶羧酸铬对生长肥育猪生产性能、胴体性状及血清生化指标的影响 总被引：1，自引：0，他引：1
本试验选用 40头体重约 2 8kg的杜× (大×长 )三元杂交猪 ,随机分为 4组 ,分别饲喂添加0、2 0 0、 40 0、 60 0 μg/kg铬 (吡啶羧酸铬 )的玉米—豆粕型饲粮 (生长、肥育期粗蛋白水平分别为1 7 0 %、 1 5 0 % ) ,直至体重约 95kg左右结束。结果表明 ,铬水平对生长期 (约 2 8～ 60kg)日增重、采食量、料重比无显著影响 ,也不影响血清钙、镁、钾、钠、氯、尿素氮浓度。虽然肥育阶段 (约 60～ 95kg) 40 0 μg/kg铬组的日增重和 60 0 μg/kg铬组的日增重、饲料转化效率有降低趋势 ,但各组间日增重、料重比、采食量差异不显著。铬不影响肥育猪血清镁、钾、钠、尿素氮浓度 ,但对氯、钙浓度有影响 (P <0 0 5 )。纵观全期来看 ,铬不影响生长肥育猪全期的生产性能 (P >0 0 5 )。虽然 60 0 μg/kg铬组有增加瘦肉率、降低脂肪率的趋势 ,但肥育猪各组间胴体性状无显著差别。以上结果提示 ,在本试验条件下 ,添加 2 0 0～ 60 0 μg/kg铬 (吡啶羧酸铬 )对生长肥育猪生产性能和胴体性状无显著影响。 相似文献
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试验旨在研究饲粮铬水平对育成期笼养蛋鸭生长性能、血液生化指标的影响。试验采用单因素完全随机分组设计,选择健康28日龄金定蛋鸭180只,随机分成5组,每组6个重复,每个重复6只鸭。对照组(Ⅰ组)饲喂玉米-豆粕型基础饲粮,试验组(Ⅱ～Ⅴ组)分别在基础饲粮中添加0.15、0.30、0.45、0.60 mg/kg铬(吡啶羧酸铬),试验期6周。结果表明:①在饲粮中添加铬(吡啶羧酸铬)对笼养蛋鸭的日增重影响差异显著(P<0.05),但对采食量和料重比影响差异不显著(P>0.05);②一定量的铬(吡啶羧酸铬)对笼养蛋鸭的血糖、总胆固醇、甘油三酯产生显著影响(P<0.05),并促进了血清总蛋白、白蛋白的提高,同时显著降低了血清尿素氮的含量(P<0.05)。最终通过二次曲线回归方程对添加量和测定指标结果进行回归分析,得出结论:铬(吡啶羧酸铬)在育成期笼养蛋鸭饲粮中最适宜的添加量为0.297 0～0.422 5 mg/kg。 相似文献
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饲粮锌和钙水平对蛋鸡组织中矿物元素含量的影响 总被引：1，自引：0，他引：1
在玉米—豆饼型基础饲粮中添加不同水平锌和钙,研究了饲粮锌和钙水平对蛋鸡不同组织中九种矿物元素含量的影响。结果表明,肝脏、胰脏和胫骨中锌含量对饲粮锌水平的反应比其它组织敏感。高锌饲粮使血液钙、镁、锰、铜和磷含量,输卵管磷和钾含量显著降低。高钙饲粮使血液铜,肝脏锌、铜、锰、镁、磷、钾和钠含量,胰脏铜含量,肌肉锌含量,胫骨镁、锰、铁、铜和钾含量显著降低,但使血液和肺脏磷含量显著提高。 相似文献
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铬对猪生产性能的影响 总被引：6，自引：0，他引：6
1 铬对猪的应激和免疫功能的影响 有研究表明,无应激的情况下,断奶仔猪日粮中添加铬,可以改善仔猪的生长性能,促进淋巴细胞的增生;存在应激的情况下,铬的添加,却没有缓和因应激所造成的生长抑制。铬能降低血清可的松的水平,而含可的松的糖皮质激素抑制免疫系统功能。另外补添有机铬,可提高妊娠母猪的体液免疫性能。 2 铬对猪生长性能的影响 Chung等(1995)在72头体重为60kg的育肥猪日粮中,添加200'ag/kg吡啶羧酸铬进行52d的饲喂试验,结果表明添加铬可改善其生长性能。Terry等(1997)报道,日粮赖氨酸不足或处于临界水平时,添加200,ag/kg的甲基吡啶酸铬,可改善育肥猪的饲料效率和日增重。美国堪萨斯州州立大学的Smith等也发现,猪日粮中添加200tg/kg铬(以三价烟酸铬的形式),平均日增重与饲料转化率都有所改善。Steele等(1982)报道,日粮添加10～100'ag/kg吡啶羧酸铬,可提高生长速度和饲料报酬,而添加400'ag/kg和800'ag/kg铬,日增重和日采食量降低,但并不影响饲料报酬。 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
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献