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41.
Ge—132在蛋鸡体内的药代动力学 总被引:2,自引:0,他引:2
给24只蛋鸡单剂量灌服Ge-132,分别于0.25~12小时采集血液、肝脏、肾脏、脾脏、卵巢和卵子,用石墨炉原子吸收分光光度法测定样品锗含量,进行药时曲线拟合和动力学参数分析。结果表明,血液中锗有2只鸡符合一级吸收单室开放模型,药代动力学参数为T_(1/2ka)0.2562±0.0302h,T_(1/2k) 3.9657±0.7075h,Tp1.1556±0.1332h,Cmax 2.1621±0.4165uσ/ml,AUC10.6164±0.1748mg/L.o;另4只鸡符合一级吸收双室开放模型,参数为T_(1/2k) 0.3996±0.2606h,T_(1/2α) 0.8513±0.1626h,T_(1/2β)4.7368±0.3652h,Tp1.0116±0.4574h,Cmax 2.6134±0.4574μg/ml,AUC13.3926±3.4651mg/Lh,在各种组织器官中均呈现一级吸收单室开放模型,其消除速率以脾脏最快,依次为脾>肝>肾>卵巢>卵子,表明了蛋鸡体内的Ge-132代谢在个体和不同器官隔室间存在很大差异。 相似文献
42.
有机铬对热应激蛋鸡生产性能和血液生化指标的影响 总被引:4,自引:0,他引:4
试验选用91周龄新罗曼商品蛋鸡480只,按2×2双因子试验设计随机分为5组,对照组饲喂不添加铬的玉米-豆粕型基础日粮,4个试验组饲喂在基础日粮中分别添加了以吡啶羧酸铬或酵母铬来源的0.2mg/kg或0.4mg/kg的日粮,试验30d,以研究有机铬对热应激蛋鸡生产性能和血液生化指标的影响。试验结果显示:①有机铬能在一定程度上促进热应激蛋鸡的蛋白质利用,提高热应激蛋鸡的生产性能;②铬水平对血清尿素氮有极显著的影响(P<0.01),添加0.4mg/kg铬组均极显著地低于对照组(P<0.01),说明了补铬能够抑制由高温引起的蛋白质分解过程,从而起到缓解高温应激的作用;③吡啶羧酸铬和酵母铬在作用效果上无显著的差异;从经济效益方面考虑,0.4mg/kg铬水平的酵母铬和吡啶羧酸铬经济效益较高。 相似文献
43.
酵母菌培养物对蛋鸡生产性能及蛋品质的影响 总被引:2,自引:0,他引:2
270只19周龄的ISABrow母鸡随机分3组处理,每个处理5个重复,研究酵母培养物对产蛋鸡产蛋性能和蛋品质的影响。试验为期16周。酵母培养物在试验中的添加水平分别为0%、0.1%、0.2%。试验中采用的玉米-豆粕型基础日粮中粗蛋白质为16.0%,能量为2800kcal/kg。试验结果表明,饲喂添加0.1%酵母培养物组产蛋鸡的生产性能和每日产蛋量显著提高(P<0.05);各处理组之间的蛋重、饲料摄入和饲料转化率无显著差别;试验组与对照组的蛋壳质量、哈氏单位、蛋黄颜色和蛋黄中脂肪酸含量也无显著差别。 相似文献
44.
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46.
不同光增方式和周期对蛋鸡蛋品质和血液生化指标的影响 总被引:1,自引:0,他引:1
研究光增方式和光照周期对蛋鸡蛋品质和血液生化指标的影响。将20周龄海兰褐商品蛋鸡320只,随机分为8组,每组4个重复,每个重复10只鸡。试验光照周期采用渐增和骤增2种,光周期设11L∶13D、13L∶11D、15L∶9D、17L∶7D4个水平。结果表明:①不同光增方式对蛋形指数和哈氏单位有显著影响(P<0.05),以渐增条件下较好。不同光增方式对血液生化指标没有显著影响(P>0.05)。②不同光照周期对蛋黄颜色有显著影响(P<0.05),以15L∶9D处理组蛋黄颜色最好。不同光照周期对血液生化指标有一定影响,以13L∶11D处理组较好。 相似文献
47.
本试验旨在通过在日粮中添加不同剂量的硒(0、0.05、0.1、0.2mg/kg日粮),研究蛋鸡换羽过程中激素的变化,探讨硒影响强制换羽的机理。试验结果表明:微量元素硒能够影响换羽过程中血浆T3、T4、促黄体生成激素、黄体酮、雌二醇含量,但是硒参与强制换羽与硒对甲状腺激素代谢的影响无关,硒可能是参与了促黄体生成激素、黄体酮、雌二醇的代谢影响了强制换羽的效果。 相似文献
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49.
《The Journal of Applied Poultry Research》2006,15(2):256-265
It is well established that the use of alfalfa in diets for monogastric animals is limited by its high fiber content. However, alfalfa is a natural source of xanthophylls and gives poultry products a desirably yellow color. In addition, alfalfa saponins may contribute to reduce the levels of cholesterol in the meat and egg yolk. We have investigated the potential utilization of β-glucanases and β-1,4-xylanases for enhancing the nutritive value of alfalfa for laying hens. An experiment was conducted with 864 ISA Brown layer hens from 40 to 52 wk of age and fed on diets containing rye (19.6%) or rye and alfalfa (15.1%). The results suggested that inclusion of alfalfa in the diets reduced body weights and total egg mass (P < 0.01). Dietary supplementation with polysaccharidases was unable to significantly improve the performance of laying hens. However, egg yolks from birds that consumed diets containing alfalfa were more deeply pigmented, presenting an increase in yellowness (b*). In contrast, at the percentage of incorporation tested, inclusion of alfalfa in the diets was unable to lower the levels of cholesterol content in the egg yolk. Taken together the results suggest that exogenous plant cell wall hydrolases are not effective for improving the nutritive value of alfalfa-containing diets for laying hens, although inclusion of small percentages of the dehydrated leguminous meal may directly affect the quality of the generated poultry products. 相似文献
50.
《The Journal of Applied Poultry Research》2006,15(3):355-361
This experiment was conducted to determine the effects of cage location and tier level with respect to light intensity on egg production and egg quality of hens housed in a semiconfined facility. Hens (ISA Brown, n = 225) at 75 wk of age were placed into 3-tier cages as top (T), middle (M), and bottom (B) tiers located in cages illuminated artificially (EI), by window (FW), or between corridors (C) for 2 mo. Light intensity was measured monthly for each cage at 5 cm from feeders every 6 h. Egg production was recorded daily and egg quality was assessed biweekly. Light intensity was the greatest for cages in the FW group (151.9, 119.8, and 89.8 lx for tiers T, M, and B, respectively), followed by EI (52.6, 54.5, and 51.0 lx for tiers T, M, and B, respectively), and C (44.5, 23.4, and 4.7 lx for tiers T, M, and B, respectively). Hens at location EI had greater egg production than hens at FW and C. Egg production for hens at tier T was also greater than for hens at tiers M and B. Egg production for hens at EI and C decreased quadratically, whereas that for hens at FW decreased linearly from tiers T to B. Cage location, but not tier level, affected egg weight. Hens at EI and FW produced heavier eggs than hens at C. Shape index, yolk color, and yolk index were independent of cage location and tier level. Hens at EI and FW produced eggs with thinner and weaker shells than hens at C. Moreover, eggshell strength increased linearly from tier T to B. Both albumen index and Haugh unit were the greatest for hens at FW, followed by EI and C. Their responses to cage location varied with tier levels. In conclusion, variation in light intensity in multitier cage systems in semiconfined laying hen houses may be a contributing factor for depressed laying performance and egg quality. 相似文献