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1.
安普霉素对仔猪内分泌的调控作用及血液生化指示的影响 总被引:4,自引:0,他引:4
采用单因子试验设计 ,28日龄大长北三元杂交断奶仔猪72头随机分为3组 ,研究饲料中添加不同剂量的安普霉素 (0、20、90mg/kg)对仔猪内分泌的调控作用及血液生化指标的影响。试验期为4周。结果表明 :仔猪日粮中添加90mg/kg的安普霉素可促进机体与生长有关的内分泌活动 ,提高内源激素 (生长激素、胰岛素、甲状腺激素T3)水平 (P<0.05),从而促进肌肉蛋白沉积 ;并具有显著降低血液中氨、尿素氮含量和提高血糖水平的作用 (P<0.05) ,表明安普霉素对仔猪具有增加氮沉积 ,促进蛋白质合成、抑制蛋白质分解的作用 相似文献
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125I-labelling was used to characterise the surface components of five stocks of Trypanosoma evansi. Two components of 67 and 60.5 kD were labelled in two of the stocks, a single 60.5 kD component in two other stocks and no components in the remaining stock. These differences are probably related to the labelling method and biochemical differences between the stocks. 相似文献
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采用3×2×2因子饲养试验和2×2×2因子代谢试验,研究金霉素与赖氨酸和蛋氨酸的交互作用对肉仔鸡生产性能的影响,及金霉素对两种氨基酸代谢的影响。金霉素在饲料中添加150 mg/kg时,对0-3周肉仔鸡具有显著的促生长作用(P<0.01);并显著提高肉仔鸡的饲料采食量和饲料转化率(P<0.01),促进氮沉积(P<0.01)。对4-6周肉仔鸡的生产性能无显著影响(P>0.05);金霉素、赖氨酸和蛋氨酸存在显著的互作关系(P<0.05)。金霉素的促生长效果受饲料中赖氨酸和蛋氨酸含量的影响,当日粮中赖氨酸水平为1.3%,蛋氨酸水平为0.6%时,肉仔鸡的生长性能最高。金霉素对赖氨酸的利用率没有显著影响(P>0.05),对蛋氨酸和胱氨酸的表观利用率具有显著抑制作用(P<0.05)。研究结果表明持续低剂量金霉素与蛋氨酸和赖氨酸具有交互作用,这种互作关系影响彼此对肉仔鸡生产性能的作用效果,金霉素具有提高肉仔鸡赖氨酸需要量的作用。 相似文献
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Response time of broiler chickens to cimaterol: meat tenderness, muscle composition fiber size, and carcass characteristics. 总被引:4,自引:0,他引:4
The response time to cimaterol (CIM), a beta-adrenergic agonist, by broiler chickens for carcass characteristics, muscle composition, muscle fiber size, catheptic enzyme activity, and tenderness was determined. Two trials were conducted in which chickens were fed a control diet (CON) containing 0 ppm of CIM or a diet containing 1 ppm of CIM. Trial 1 consisted of 55, 31-d-old broiler chickens individually fed for up to 48 h. At 0, 6, 12, 18, 24, and 48 h, five CON and five CIM-fed chickens were killed. Trial 2 consisted of 160, 33-d-old broiler chickens group-fed for up to 14 d. At 2, 4, 6, 8, 10, 12, and 14 d, 10 CON and 10 CIM-fed chickens were killed. The breast muscle (BM) and leg muscle (LM) weight, cathepsin B and L activities, DNA, RNA, and protein concentration, and BM shear force value (SFV) were measured in both trials. Thigh muscle (TM) SFV were measured in Trial 2 only. Fiber size of BM was measured (five birds per treatment) at d 2, 6, 10, and 14. In Trial 1, BM weight and SFV were lower in CIM-fed birds at 6 h (P less than .05). In Trial 2 BM SFV were higher at d 8 (P = .06) and d 10 (P less than .05) in CIM-fed chickens. The SFV of CIM-fed chickens were higher at d 4, 8, 10, 12, and 14 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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R. S. Jones 《The Journal of small animal practice》1992,33(9):423-429
There are a variety of factors which are likely to influence the action of muscle relaxants in canine anaesthesia. These include age, body temperature and muscle diseases. Of the anaesthetic agents it is only the inhalational anaesthetic agents which significantly increase the duration of action of muscle relaxants. Antibiotic therapy particularly with the aminoglycoside antibiotics is likely to increase their duration of action. The indications for the use of muscle relaxants and the main contraindications such as the absence of anaesthetic equipment and the inability to ensure unconsciousness are discussed. The choice of anaesthetic technique together with a discussion on the premedication induction and maintenance of anaesthesia are important factors when using relaxants as is the technique of artificial ventilation. The various advantages and disadvantages of neuromuscular block monitoring are discussed as is the reversal of neuromuscular block. 相似文献
8.
Characterization of Brucella canis protein antigens and polypeptide antibody responses of infected dogs 总被引:1,自引:0,他引:1
The cytoplasmic protein antigens (CPAg) of Brucella canis were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and analysis of 35S-labeled polypeptides. Approximate molecular weights of the immunoreactive polypeptides were determined by migration patterns of the immunoprecipitated polypeptides after SDS-PAGE or Western immunoblotting of sera collected at various times after experimental infection of dogs. Polypeptides were specifically precipitated by sera of infected dogs, but not from the sera of normal or false-positive (seropositive, non-infected) animals. During the initial month after infection, proteins with molecular weight masses (MW) of approximately 18, 22, 31, 42 and 54 kDa were commonly recognized. A 20-kDa polypeptide was first recognized at 8-10 weeks after infection, but it was detected inconsistently after 6 months. Additional polypeptides detected from 2 to 12 months post-infection had MW of 22, 66-68 and, less regularly, 42, 60, 82, 100 and greater than 200 kDa. The polypeptides most consistently recognized in sera from B. canis-infected dogs had MW of 18, 22 and 68 kDa. 相似文献
9.
L.E. Young D.H. Bartram M. Diamond A. Gregg R.S. Jones 《Veterinary anaesthesia and analgesia》1991,18(Z1):171-174
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