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161.
Wei Yao Hongliang Zhao Jie Li Zhijun Wang Yuhuang Han Shuren Dong Yuejiang Wang Fenglai Wang 《畜牧与生物技术杂志(英文版)》2011,2(3):141-152
This experiment was conducted to investigate the effects of different ratios of n-6:n-3 polyunsaturated fatty acids (PUFA) in sow diets on the performance of lactating sows and their piglets at low digestible energy intakes.Twenty-one pregnant Landrace sows were assigned to one of three diets from day 108 of gestation until weaning (26 to 29 d),containing n-6∶n-3 PUFA ratios of 3∶1,8∶1 and 11∶1.The effects on sow and litter production traits and on sow body condition were examined.There were no differences among treatments in daily feed intakes or in changes in sow weight and back-fat levels during lactation.Litter size,litter weight at birth and weaning and litter average daily weight gain were also unaffected by treatment.As expected,large differences were observed in n-6 and n-3 fatty acids in the colostrum and plasma of sows and piglets (P < 0.01 ).The ratio of n-6∶n-3 PUFA the diet was positively correlated with those in colostrum,sow plasma and piglet plasma ( R2 =0.55,0.80 and 0.80,respectively).Sow plasma insulin and IGF-I levels at weaning were unaffected by the treatments.Plasma leptin ( P < 0.05) concentrations were increased in sows fed the diet with a n-6∶ n-3 ratio of 8∶1.Immunoglobulin concentrations in colostrum were not altered by dietary treatment.Plasma IgG concentrations at d 14 were highest in piglets from sows fed the 8∶1 ratio of n-6∶n-3.Furthermore,this group had the highest IgA concentrations at day 21 of lactation compared with the other two groups ( P < 0.05 ).In summary,our study demonstrated that at low digestible energy levels,altering the ratio of n-6∶n-3 PUFA in the diets for lactating sows affected immune components and the fatty acid composition of lactating sows and their piglets.Further studies are needed to examine whether higher levels of fat supplementation than those used in the present study ( 1.5% ) can successfully enhance performance. 相似文献
162.
163.
在玉米拔节期对12个常用玉米自交系喷施200 mg/L的乙烯利,探讨了乙烯利对不同基因型玉米节间伸长和内源激素的影响。结果表明,乙烯利处理后,除郑58、L6M、K12、豫自87-1和8085泰5个自交系各性状与对照相比无显著差异外,其余自交系表现为株高和穗位高降低,基部第3、4、5节间长度缩短,内源激素生长素(IAA)含量、赤霉素(GA4)与脱落酸(ABA)的比值降低,ABA含量升高,且差异均达显著或极显著水平,而GA4含量无明显变化规律。不同玉米自交系的形态指标(株高、穗位高和第3、4、5节间长度)和内源激素(IAA含量、ABA含量及GA4/ABA比值)均存在很大差异,相对变化百分数从6.41%到102.64%不等。各指标均能反映出不同基因型玉米植株对乙烯利的敏感性,其中,敏感性相对较强的有昌7-2、浚928、Mo17和丹340;相对较弱的有郑58、L6M、K12、豫自87-1和8085泰。 相似文献
164.
中国沙棘和俄罗斯沙棘叶片在不同土壤水分条件下脯氨酸、可溶性糖及内源激素含量的变化 总被引:18,自引:2,他引:18
通过对中国沙棘(Hippophaerhamnoidessinensis)和俄罗斯沙棘(Hippophaerhamnoides)在野外不同生境和田间不同干旱胁迫条件下叶片脯氨酸、可溶性糖及内源激素含量的变化进行研究后发现:坡上土壤水分含量显著低于沟底的土壤水分含量,坡上中国沙棘叶片中的脯氨酸、可溶性糖含量比沟底明显增加,雌株的增加幅度大于雄株。在田间不同的干旱胁迫条件下,沙棘叶片内脯氨酸含量随着干旱胁迫程度和干旱胁迫时间的延长而增加,脯氨酸积累能力为中国沙棘>俄罗斯沙棘,雌、雄株之间的差异为雌株>雄株。沙棘叶片内可溶性糖含量随着干旱胁迫程度和干旱胁迫时间的延长而持续增加,沙棘叶片可溶性糖的积累能力因雌雄株和品种不同而出现一定差异,表现为俄罗斯沙棘>中国沙棘,雌株>雄株。随着土壤含水量的降低,沙棘叶片中的ABA显著增加,IAA和ZR的含量明显降低,GA的含量在胁迫初期升高,之后逐渐下降;中国沙棘叶片内源激素的变化幅度小于俄罗斯沙棘,雌株的变化幅度小于雄株。综合沙棘叶片中脯氨酸、可溶性糖、内源激素的变化,在干旱的适应性方面,中国沙棘和沙棘雌株更具有优势。 相似文献
165.
渗透胁迫下烤烟根和叶片中内源激素含量的变化 总被引:5,自引:0,他引:5
采用酶联吸附免疫测定(ELISA)技术分析了渗透胁迫下烤烟根和叶片中脱落酸(ABA)、生长素(IAA)、赤霉素(GA3)和异戊烯基腺嘌呤(iPA)4种内源激素含量的变化。结果表明,渗透胁迫下烤烟叶片水势降低,蛋白质含量增加,根和叶中ABA和iPA含量升高,IAA和GA3含量减少。培养液渗透势-0.5 MPa与-0.25 MPa两处理相比,前者烟叶水势和ABA含量较低,蛋白质及IAA、GA3和iPA含量较高,根中iPA和叶中ABA含量达到高峰及根中GA3含量出现低谷所需时间较短,其它指标的变化二者同步。根与叶中激素含量相比,在胁迫处理前期(6 h)根中IAA和GA3含量的降低幅度较大,ABA含量峰值出现较早,说明烤烟根中的激素对渗透胁迫的反应更加敏感。 相似文献
166.
杂交水稻再生芽萌发生长与植株内源细胞分裂素含量变化的关系 总被引:1,自引:1,他引:1
采用植物激素ELISA方法,研究了杂交水稻各器官内源细胞分裂素(iPA)的变化及其与再生芽萌发生长的关系。结果表明,头季稻齐穗后5-19d稻株叶和叶鞘中内源激素iPA的含量较低,再生芽生长缓慢或处于休眠状态;齐穗19d以后,内源激素iPA含量增加,再生芽萌发、伸长的速度也相应加快。前期(齐穗后19d)下部节位茎中iPA含量高于上部节位,低位芽长于高位芽;后期(齐穗后33d)上部节位茎、芽的iPA含量高于下部节位,上位芽生长速度则快于下位芽,可见,再生芽萌发生长与内源激素iPA变化关系密切。 相似文献
167.
为研究不同中性洗涤纤维(NDF)水平日粮对妊娠母兔繁殖性能及血清生化指标和激素的影响,探讨适宜的NDF需要量,将100只体质量相近、胎次和配种日期基本一致的经产新西兰母兔随机分为5组,每组20只,分别饲喂含24%、27%、30%、33%和36%5种NDF水平的日粮。结果表明:日粮NDF水平对妊娠母兔窝产仔数和初生个体质量无显著影响(P0.05),对窝产活仔数、初生窝质量和窝活仔质量影响显著(P0.05),均以30%NDF组最高。30%NDF组血清蛋白质和葡萄糖含量及24%NDF组甘油三酯含量显著高于36%NDF组(P0.05),血清尿素氮和胆固醇浓度不受NDF水平显著影响(P0.05)。随NDF水平升高,血清IGF-1、E2、P4和PRL水平呈先升高后降低趋势,30%NDF组显著高于24%和36%NDF组(P0.05)。综合分析,妊娠母兔日粮最适宜的NDF水平为30%。 相似文献
168.
以杉木‘洋020’扦插苗和‘洋020’组培苗为实验材料,通过盆栽实验,在调查不同埋土深度处理无性系萌蘖情况的基础上,应用酶联免疫吸附法测定了杉木无性系萌蘖高峰期枝叶、基部韧皮部、根尖等不同器官吲哚乙酸、赤霉素、细胞分裂素及脱落酸含量差异。结果表明:组培苗萌蘖能力强于扦插苗;随着埋土深度增加,2个无性系苗萌蘖能力均呈降低的趋势。不同埋土深度处理根尖和枝叶内源激素含量较高;随着培养时间延长,无性系枝叶吲哚乙酸含量呈上升趋势,赤霉素含量呈下降趋势;埋土深度6 cm处理有利于枝叶及根尖脱落酸的积累,埋土深度9 cm处理有利于根尖细胞分裂素的积累;无性系萌蘖与埋土深度呈极显著负相关,与赤霉素含量呈极显著正相关。不同埋土深度对杉木无性萌蘖有一定的影响,杉木无性系萌蘖高峰期均在8月份;不同器官植物内源激素含量是影响埋土深度处理杉木无性系萌蘖的主要影响因子之一。 相似文献
169.
CHENG Yuan ZHAO Xiao-yu LI Yuan-yuan ZHAO Quan-zhuang ZHU Jian-ping AI Shan-jiang LI Hai-ying 《中国畜牧兽医》2017,44(11):3264-3269
This experiment was aimed to study the changes of reproductive hormone and regulation of follicle development during the reproductive cycle of Yili goose in Xinjiang. 2 years old Yili goose were chosen which were in good health and similar weight. 32 samples were randomly selected to take blood samples for hormone detection during the laying, broodiness and ceased periods, and 15 samples were randomly selected to gather ovarian tissue for the observation of the development of ovary and follicular. The results showed that during the laying period, the GnRH of the Yili goose was extremely significantly higher than the broodiness and ceased periods of 16.78% and 58.29% (P<0.01);PRL was significantly lower than the broodiness period of 13.00% (P<0.05), and was extremely significantly higher than the ceased period of 28.94% (P<0.01); FSH was higher than the broodiness period of 6.98% (P>0.05),and was extremely significantly higher than the ceased period of 21.12% (P<0.01); LH was extremely significantly lower than the broodiness period of 8.38% (P<0.01),and was extremely significantly higher than the ceased period of 16.84% (P<0.01); E2 were extremely significantly higher than that the broodiness and ceased periods of 29.80% and 112.40% (P<0.01); P4 levels were extremely significantly higher than the broodiness and ceased periods of 28.89% and 30.34% (P<0.01). The ovary volume and weight of Yili goose were extremely significantly higher than that of broodiness and ceased periods (P<0.01). In the laying period, the mature follicles of Yili goose were significantly larger than that of the broodiness and resting periods, the number of secondary follicles was more and the number of primary follicles was lesser. Ovarian growth and mature follicle atresia, granule layer shrinkage, inward depression, cytoplasmic cavity, follicular atrophy at all levels in the broodiness period. The follicle cytoplasmic cavity of the ovary was larger in the ceased period than broodiness period, and inward concave further deeper, a large number of primordial follicles evenly arranged. Thus, during the laying period, the responses of GnRH, E2 and LH of Yili goose were active and played a leading role on the development of ovarian and follicular. PRL and LH maintained a high level of secretion, cooperated to maintain the broodiness behavior during the broodiness period. 相似文献
170.
以中国水仙(Narcissus tazettaL.var.chinensis Roem)为材料,用前期试验筛选出的最佳矮化浓度:A 50 mmol.L-1、B24.5 mmol.L-1、PP33340 mg.L-1及人工模拟气候处理水仙植株,矮化处理后水仙叶片IAA、GA3含量、(IAA+GA3)/ABA比值均显著降低;ABA含量的变化则因处理方式的不同呈现不同的变化趋势;A和B矮化处理降低了Trans-Z、DHZR的含量和(Trans-Z+DHZR)/ABA的比值。并确定了高效液相色谱测定水仙叶片IAA、ABA、GA3及Trans-Z、DHZR含量的检测条件。 相似文献