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不同生长年限敖汉苜蓿草地土壤呼吸研究 总被引:2,自引:0,他引:2
使用便携式土壤呼吸测定仪测定农牧交错带1年、2年和4年生敖汉苜蓿人工草地的土壤呼吸,并同步测定0~5 cm土层的温度和含水量.结果表明:敖汉苜蓿草地土壤呼吸的日最高值出现在14:00-18:oo,夜间最高值出现在4:00-6:00,全天最低值出现在10:00左右;不同生长年限敖汉苜蓿草地的土壤呼吸速率,总体变化趋势是4年生>2年生>1年生;土壤呼吸与土层温度呈显著的指数增长关系,且相关性高于土壤呼吸速率与土壤含水量的相关性;5 cm土层的地温和土壤含水量较土壤温度或空气湿度能更好地解释土壤呼吸的变化. 相似文献
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本实验研究旨在探究BAD基因在敖汉细毛羊中的不同发情时期卵巢中表达量的变化规律以及对生殖激素的影响,为探讨其与绵羊发情的关系奠定基础。首先利用放射免疫方法测定敖汉细毛羊血液中促卵泡激素(FSH)、促黄体生成素(LH)、雌二醇(E_2)和孕激素(P_4)的浓度,然后利用qRT-PCR检测乏情期、发情前期、发情间期和发情期卵巢BAD基因的表达量变化。结果表明:卵巢中BAD基因在发情前期的表达量极显著高于乏情期、发情期和发情间期(P0.01),在发情期的表达量极显著高于乏情期和发情间期(P0.01),乏情期和发情间期的表达量基本相同(P0.05);E_2和LH浓度在BAD基因表达量最高的发情前期维持较高水平,P_4的浓度维持较低水平。综上可知,BAD基因的表达可能促进了E_2和LH浓度升高,抑制了P_4产生,进而影响细毛羊发情,可为绵羊发情的研究提供借鉴。 相似文献
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Background: Increasing the polyunsaturated fatty acid (PUFA) content and decreasing the saturated fatty acid (SFA) content of mutton can help to improve its nutritional value for consumers. Several laboratories have evaluated the effects of vitamin E on the fatty acid (FA) composition of muscle in sheep. However, little information is available on wool sheep, even though wool sheep breeds are an important source of mutton, especially in northern China where sheep are extensively farmed. The present study was designed to address the effects of vitamin E on muscle FA composition in male Aohan fine-wool sheep. Methods: Forty-two male Aohan fine-wool lambs (5 mo old) with similar initial body weight were randomly divided into seven groups and fed diets supplemented with 0 (control group), 20, 100, 200, 1,000, 2,000, or 2,400 IU/sheep/d vitamin E for 12 mo. Three lambs from each group were slaughtered to measure vitamin E and FA content in the Iongissimus lumborum (LL) and gluteus medius (GM) muscles. Results: Vitamin E concentrations in the LL and GM increased significantly after 12 mo of vitamin E supplementation (P 〈 0.05). However, this increase did not occur in a dose-dependent manner because the muscle vitamin E concentration was highest in the 200 IU/sheep/d group. Dietary vitamin E supplementation also caused a significant reduction in SFA content and an increase in monounsaturated FA (MUFA) content in the LL and GM (P 〈 0.05). All six doses of vitamin E significantly increased cis9 tronsl -conjugated linoleic acid (cgtl -CLA) content in the LL compared with the control group (P 〈 0.05). Conclusions: Dietary supplementation with vitamin E increased muscle vitamin E content and improved the nutritional value of mutton by decreasing SFA content and increasing MUFA and c9tl 1-CLA contents in Aohan fine-wool sheep. These effects were greatest in sheep fed a diet containing 200 IU/sheep/d vitamin E. 相似文献
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消化能和粗蛋白进食水平对敖汉细毛羊羊毛生长长度的影响 总被引:1,自引:0,他引:1
旨在研究消化能和粗蛋白进食水平对敖汉细毛羊羊毛生长长度的影响。采用2因素5水平的随机区组试验设计,将125只2~3岁成年敖汉细毛羊(空怀母羊)分为25个处理组,每组5只羊,分别设计进食85%、100%、115%、130%、145%的维持需要消化能为每kg代谢体重0.549MJ和维持需要粗蛋白为每kg代谢体重3.576g,6个月饲养期,测定羊毛生长长度。结果表明:在85%~145%的维持需要范围内,消化能进食水平与羊毛生长长度存在3次函数回归关系(R>0.99),2个拐点都位于100%和130%维持消化能水平附近,从85%提高至100%维持需要时,羊毛生长长度呈显著提高,平均提高10.70%。从100%提高至130%维持需要时,羊毛生长长度无显著提高。从130%提高至145%维持需要时,羊毛生长长度平均提高4.58%。粗蛋白进食水平与羊毛生长长度存在二次函数回归关系(R>0.86),在不同消化能进食水平下,粗蛋白进食水平从85%提高至115%时,羊毛生长长度均有明显提高,平均提高7.71%;从115%提高至145%时,羊毛生长长度无明显变化。敖汉细毛羊空怀母羊羊毛生长对能量的需求以满足其维持需求为宜,对粗蛋白的... 相似文献
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研究采用父系半同胞相关法和单元内半同胞相关法分别估算了敖汉细毛羊的初生重、断乳重、断乳毛细度、周岁毛细度、周岁毛长、周岁剪毛量、周岁剪毛后体重、2周岁毛细度、2周岁毛长、2周岁剪毛量、2周岁剪毛后体重的遗传力。结果发现,这些性状的遗传力均为中高遗传力,在0.1~0.7之间。 相似文献
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水肥耦合对敖汉苜蓿营养成分的影响 总被引:5,自引:0,他引:5
采用3因素完全裂区试验设计,在大田条件下研究氮、磷、水对敖汉苜蓿营养成分及其变化规律的影响。结果表明:粗蛋白和干物质含量随着氮、磷肥用量的增加而升高,随着灌水量的增加而降低。随着氮、磷肥用量和灌水量的增加纤维含量降低,粗脂肪含量升高。粗灰分含量随着氮肥用量和灌水量增加而升高,随着磷肥用量增加而降低。粗蛋白、粗灰分、粗脂肪、酸性洗涤纤维、中性洗涤纤维最佳营养成分所需的水肥组合为:氮肥300kg.hm-2+磷肥450kg.hm-2+灌水2300m3.hm-2。干物质含量最高的处理为:氮肥300kg.hm-2+磷肥450kg.hm-2+灌水1150m3.hm-2。 相似文献
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Background
Increasing the polyunsaturated fatty acid (PUFA) content and decreasing the saturated fatty acid (SFA) content of mutton can help to improve its nutritional value for consumers. Several laboratories have evaluated the effects of vitamin E on the fatty acid (FA) composition of muscle in sheep. However, little information is available on wool sheep, even though wool sheep breeds are an important source of mutton, especially in northern China where sheep are extensively farmed. The present study was designed to address the effects of vitamin E on muscle FA composition in male Aohan fine-wool sheep.Methods
Forty-two male Aohan fine-wool lambs (5 mo old) with similar initial body weight were randomly divided into seven groups and fed diets supplemented with 0 (control group), 20, 100, 200, 1,000, 2,000, or 2,400 IU/sheep/d vitamin E for 12 mo. Three lambs from each group were slaughtered to measure vitamin E and FA content in the longissimus lumborum (LL) and gluteus medius (GM) muscles.Results
Vitamin E concentrations in the LL and GM increased significantly after 12 mo of vitamin E supplementation (P < 0.05). However, this increase did not occur in a dose-dependent manner because the muscle vitamin E concentration was highest in the 200 IU/sheep/d group. Dietary vitamin E supplementation also caused a significant reduction in SFA content and an increase in monounsaturated FA (MUFA) content in the LL and GM (P < 0.05). All six doses of vitamin E significantly increased cis9 trans11-conjugated linoleic acid (c9t11-CLA) content in the LL compared with the control group (P < 0.05).Conclusions
Dietary supplementation with vitamin E increased muscle vitamin E content and improved the nutritional value of mutton by decreasing SFA content and increasing MUFA and c9t11-CLA contents in Aohan fine-wool sheep. These effects were greatest in sheep fed a diet containing 200 IU/sheep/d vitamin E. 相似文献10.