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991.
EffectsofOneGenerationDivergentSelectionforPlasmaveryLowDensityLipoproteinConcentrationandInteractionbetweenGenotypeandNutrit... 相似文献
992.
不同温度型苜蓿产量和品质的动态分析 总被引:1,自引:0,他引:1
根据苜蓿干草产量和品质指标的实测值,用非线性函数模拟和分析了冷、暖型苜蓿的干草产量和品质指标的动态变化。结果表明,冷型苜蓿的干草产量和品质指标(除粗脂肪含量外)均优于暖型苜蓿;在快速生长阶段,冷型苜蓿的平均生长速率较暖型苜蓿高40.7%,其累积生长量在03-28以后开始超过暖型苜蓿,盛花期的产草量比暖型苜蓿高出5.3%;冷型苜蓿的粗蛋白含量从分枝期到结荚期均高于暖型苜蓿,盛花期约高出0.8%;冷型苜蓿的粗纤维含量增速较暖型苜蓿慢,盛花期其粗纤维含量较暖型苜蓿低4.3%;冷型苜蓿的粗脂肪含量05-05(初花期)前高于暖型苜蓿,05-05后反而低于暖型苜蓿4.1%。 相似文献
993.
为探讨皇竹草(Pennisetum sinese Roxb)对草鱼(Ctenopharyngodon idella)脂肪蓄积和肠道菌群组成的影响,配制3组分别含0%(对照组)、10%和20%皇竹草粉的等氮等能纯化饲料(蛋白质水平为33%,脂肪水平为8%),饲喂草鱼稚鱼[(28.51±0.04)g] 8周,每组饲料饲喂3个重复。结果显示,饲料中添加10%和20%皇竹草粉显著降低腹腔脂肪指数(P<0.05),组织切片显微结构显示,相比对照组,皇竹草粉组的草鱼肝脏脂滴数量均明显减少,脂肪细胞大小明显变小。血清中的甘油三酯(TG)、总胆固醇(TC)和游离脂肪酸(NEFA)的含量随着皇竹草粉水平的升高呈现下降趋势,其中20%添加水平相比对照组草鱼显著降低(P<0.05)。皇竹草粉组肝脏中的TG、TC和NEFA的含量均显著下降(P<0.05)。肝脏和腹腔脂肪组织中过氧化物酶体增殖物激活受体γ(pparγ)等脂肪生成相关5个基因在摄食皇竹草粉后显著下调(P<0.05),过氧化物酶体增殖物激活受体α(pparα)等4个脂肪分解相关基因在摄食皇竹草粉后显著上调(P<0.05),肝脏组织中法尼酯X受体(fxr)基因在摄食皇竹草粉后显著上调(P<0.05)。肠道菌群宏基因组学结果显示,10%和20%皇竹草粉组草鱼肠道内容物中肠道微生物的Ace、chao1、Shannon和Simpson指数均与照组存在显著差异(P<0.05),表明皇竹草粉提高了草鱼肠道内菌群种类的丰度和多样性。从门分类来看,与脂肪蓄积相关菌群,厚壁菌门(Firmicutes)的比例在皇竹草组中显著降低(P<0.05),拟杆菌门(Bacteroidetes)比例呈现上升的趋势(P>0.05)。综上,以上结果表明,饲料中添加一定量的皇竹草粉能够降低草鱼体脂蓄积,其中肠道菌群的改善可能是这一过程中的重要环节。 相似文献
994.
Absorption by sheep of dieldrin from contaminated soil 总被引:1,自引:0,他引:1
Objective To study the accumulation of dieldrin residues in sheep from ingestion of contaminated soils was studied in two experiments.
Design A controlled feeding study of sheep fed contaminated soils of different type at varying intervals.
Animals and procedure Thirty-four 2-years-old wethers were divided into four groups (one control sheep only) and fed water-soluble dieldrin or soil contaminated with aldrin and dieldrin at varying intervals in the first study. In a second study 34 similar sheep were divided into four treatments with one being a control. Sheep were fed sandy, high clay or high organic matter soils with similar dieldrin and aldrin concentrations.
Results In the first study the concentration of dieldrin in the body fat of sheep dosed with dieldrin-contaminated soil was about half that in the body fat of sheep dosed with an equivalent amount of water-soluble dieldrin. The concentration of dieldrin was almost the same in sheep fed 500 μg of total dieldrin per day as it was in sheep fed 5000 μg every tenth day, over a 50-day period. In the second experiment sheep accumu-lated nearly three times as much pesticide from a soil with a high organic matter content, and about four times as much from a soil with a high clay content, as from a sandy soil with the same dieldrin content, over a 100-day period. The half-life of dieldrin in the fat of all sheep varied between 96 and 116 days after sheep ceased ingesting contaminated soil.
Conclusions Dieldrin concentrations in the fat of sheep that consume dieldrin contaminated soil fall within 10 days of removal from the source of contamination. However, dieidrin accumulates in the wool of sheep that consume dieldrin-contaminated soil. 相似文献
Design A controlled feeding study of sheep fed contaminated soils of different type at varying intervals.
Animals and procedure Thirty-four 2-years-old wethers were divided into four groups (one control sheep only) and fed water-soluble dieldrin or soil contaminated with aldrin and dieldrin at varying intervals in the first study. In a second study 34 similar sheep were divided into four treatments with one being a control. Sheep were fed sandy, high clay or high organic matter soils with similar dieldrin and aldrin concentrations.
Results In the first study the concentration of dieldrin in the body fat of sheep dosed with dieldrin-contaminated soil was about half that in the body fat of sheep dosed with an equivalent amount of water-soluble dieldrin. The concentration of dieldrin was almost the same in sheep fed 500 μg of total dieldrin per day as it was in sheep fed 5000 μg every tenth day, over a 50-day period. In the second experiment sheep accumu-lated nearly three times as much pesticide from a soil with a high organic matter content, and about four times as much from a soil with a high clay content, as from a sandy soil with the same dieldrin content, over a 100-day period. The half-life of dieldrin in the fat of all sheep varied between 96 and 116 days after sheep ceased ingesting contaminated soil.
Conclusions Dieldrin concentrations in the fat of sheep that consume dieldrin contaminated soil fall within 10 days of removal from the source of contamination. However, dieidrin accumulates in the wool of sheep that consume dieldrin-contaminated soil. 相似文献
995.
固体脂肪对育成期幼貉的作用 总被引:1,自引:1,他引:0
通过对 4~ 6月龄的育成期幼貉饲料中添加微囊法粉末油脂及化学法固体脂肪的饲养 ,分析了貉的体重、体长、针绒毛长度、密度。结果表明 ,日粮中添加以上两种脂肪 ,对育成期幼貉的生长发育都有很好的促进作用。 相似文献
996.
997.
Knut Flatlandsmo 《Acta veterinaria Scandinavica》1973,14(5):673
In two calves fed milk replacers containing hydrogenated marine fat, collection of the duodenal chyme was carried out over a 24 hr. period, when the calves were about one and a half weeks old. The fat was partly broken down to free fatty acids (F.F.A.) before entering the duodenum. Hydrolysis was probably due to pregastric esterase. No hydrogenation of the unsaturated fatty acids was observed. 相似文献
998.
狼在60日龄至70日龄期,对粗纤维的消化率为57.1%,对粗脂肪的消化率为91.5%。根据狼消化器官结构及对碳水化合物的消化能力分析,狼为杂食性动物,与其它大科动物一样。狼在野外的数量已很稀少,应给予保护。 相似文献
999.
李峰 《吉林粮食高等专科学校学报》2003,18(4):11-13
随着人们生活水平的不断提高,脂肪的摄取量也不断增加,随之带来的是由于脂肪过量摄取而引发的各种疾病,给人们带来对脂肪和胆固醇的恐惧心理。脂肪代用品不仅能有效地降低食品中脂肪含量,降低食品的热量,而且不影响食品的营养价值,保持原有食品的风味和口感。蛋白质是很好的脂肪代用品之一。 相似文献
1000.
【目的】 研究6月龄波尔山羊与麻城黑山羊的血液生理生化指标、胴体性状、肌纤维直径、肌内脂肪含量的差异情况,以期为2个品种山羊的饲养管理、引种改良及杂交利用提供参考依据。【方法】 分别选取8只3月龄±5 d、健康的波尔山羊与麻城黑山羊在统一条件下饲养3个月,饲养结束采集血液测定白细胞数(WBC)、红细胞数(RBC)、血红蛋白浓度(HGB)、红细胞比容(HCT)、平均红细胞体积(MCV)等14项血液生理指标及肌酐(CRE)、总胆红素(TBIL)、尿素氮(BUN)、血糖(GLU)、总蛋白(TP)等14项血液生化指标;测定体重、体高、体斜长、胴体重、屠宰率、眼肌面积等12项胴体性状;屠宰后取背最长肌肌肉组织,切片后经苏木素伊红和改良油红O染色,分别检测肌纤维直径和肌内脂肪含量。【结果】 血液生理指标中,波尔山羊的红细胞比容、平均红细胞体积均显著低于麻城黑山羊(P<0.05),平均红细胞血红蛋白浓度显著高于麻城黑山羊(P<0.05),其余指标均无显著性差异(P>0.05);血液生化指标中,波尔山羊的总蛋白、球蛋白、血磷含量与淀粉酶活性均极显著低于麻城黑山羊(P<0.01),钾离子含量极显著高于麻城黑山羊(P<0.01),其余指标均无显著性差异(P>0.05);胴体性状中,波尔山羊的体重、平均日增重、背最长肌重、股二头肌重和胴体重均显著高于麻城黑山羊(P<0.05),眼肌面积极显著大于麻城黑山羊(P<0.01),其余指标均无显著性差异(P>0.05);波尔山羊的肌纤维直径极显著大于麻城黑山羊(P<0.01),肌内脂肪含量显著高于麻城黑山羊(P<0.05)。【结论】 波尔山羊与麻城黑山羊血液指标、屠宰性能均存在较大的差异,结果可为研究波尔山羊与麻城黑山羊的种质特征提供理论依据。 相似文献