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1.
试验旨在探讨白肉灵芝水提物（Ganoderma leucocontextum aqueous extracts,GLAE）对脑缺血后海马神经元的保护作用及机制。将50只健康大鼠分为对照组、模型组、GLAE低（0.05 mg/（g·BW））、中（0.1 mg/（g·BW））、高（0.2 mg/（g·BW））剂量组。利用双侧颈总动脉夹闭法建立大鼠脑缺血模型,GLAE组灌胃不同剂量的GLAE干预,对照组和模型组灌胃同体积的生理盐水,连续2周。用跳台试验方法检测记忆获得、记忆巩固和记忆再现障碍大鼠的学习记忆能力,HE染色观察大鼠海马组织的病理形态的变化,比色法检测海马组织一氧化氮合酶（nitric oxide synthase,NOS）活性和一氧化氮（nitric oxide,NO）含量,Western blotting和实时荧光定量PCR法分别检测海马组织生长相关蛋白-43（growth associated protein-43,GAP-43）和脑源性神经生长因子（brain derived neurotrophic factor,BDNF）的水平。结果显示,与对照组相比,模型组大鼠跳台试验的逃避潜伏期显著缩短、电击次数显著增加（P<0.05）;海马神经元细胞出现明显核固缩、排列松散紊乱等退行性改变,细胞数量显著减少（P<0.05）;海马组织NOS活性和NO含量均显著降低（P<0.05）;大鼠海马组织GAP-43蛋白表达量显著升高（P<0.05）;海马组织BDNF mRNA表达量显著下调（P<0.05）。与模型组相比,GLAE干预后,大鼠逃避潜伏期均显著延长、电击次数均显著减少（P<0.05）;GLAE高剂量组大鼠CA1区和齿状回锥体神经元细胞形态明显改善,神经元数量显著增加（P<0.05）;GLAE低剂量组对NOS活性影响不明显（P>0.05）,显著增加NO含量（P<0.05）,GLAE中、高剂量组NOS活性和NO含量均显著升高（P<0.05）;GLAE低、中、高剂量组海马组织GAP-43蛋白表达量均显著增加（P<0.05）;GLAE低、中、高剂量组海马组织BDNF mRNA表达量均显著增加（P<0.05）。以上结果表明,GLAE可通过提高NOS活性和NO水平、促进海马神经发生和功能恢复对脑缺血后海马神经元损伤有一定的保护作用,从而改善大鼠认知功能,0.2 mg/g GLAE效果最好。 相似文献
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用SABC免疫组织化学技术,观察家兔海马各区nNOS阳性神经元在去卵巢及雌激素替代治疗后的形态结构及分布变化,为雌激素类药物防治绝经后老年性痴呆症提供理论依据。结果表明,家兔海马各区都有nNOS阳性神经元分布;去卵巢后海马nNOS阳性神经元的形态结构及分布变化有区域差异性:与假手术对照组相比,在海马CA1区、CA3区、齿状回(DG)阳性神经元数量明显减少(P0.05),而在CA2区数量明显增多(P0.05)。CA1、CA3区和DG的阳性神经元胞体截面积明显变小,最长突起长度明显变短,第一级突起数变少,与假手术组有显著差异(P0.05)。CA2区阳性神经元胞体截面积明显变小(P0.05),最长突起长度、第一级突起数增多,但差异不显著(P0.05);nNOS阳性神经元的4种指标在雌激素替代治疗组与假手术组之间无显著差异(P0.05)。结果提示:雌激素可能通过影响海马nNOS的表达来影响脑的学习和记忆功能。 相似文献
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《科技视界》2017,(2)
目的 :研究慢性应激后小鼠海马和前脑皮层BDNF表达的变化,探讨小鼠学习记忆功能变化的机制。方法 :建立多因素慢性应激小鼠模型,通过Morris水迷宫检测小鼠空间学习记忆能力;免疫组织化学方法检测小鼠海马和前脑皮层BDNF表达水平的时序变化。结果:与对照组小鼠比较,慢性应激后即刻和24h组小鼠在水迷宫中的空间学习记忆能力明显减退(P<0.05,P<0.01),海马CA1、CA3、DG和前脑皮层BDNF的表达明显减少(P<0.05,P<0.01);而慢性应激后一周组小鼠的学习记忆能力有部分恢复,海马各区和前脑皮层BDNF的表达亦有所增加,无显著性差异。结论:BDNF在海马和前脑皮层表达的下调,可能与慢性应激后小鼠学习记忆功能的损伤有关。 相似文献
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旨在检测PPP1R3C在爱拔益加肉鸡不同组织中的表达情况，探究外源胰岛素和能量限饲对鸡体胰岛素敏感组织中PPP1R3C表达的影响。试验一，取不同发育阶段的雌性肉鸡（E14、E19、D7和D21，n=10）组织样，通过qRT-PCR技术检测PPP1R3C在不同时期胸肌中的表达；试验二，腹腔注射胰岛素（INS）或PBS，取两组注射后不同时间点（0、15、120和240 min，n=5）的D24雄性肉鸡组织样，检测PPP1R3C在肉鸡不同组织中的表达，探究外源胰岛素处理对肉鸡胰岛素敏感组织中PPP1R3C表达的影响；试验三，取D18雌性肉鸡，一组饲喂常规日粮（n=20），另一组饲喂限制30%能量的日粮（n=20），饲喂至48天屠宰取样，探究30%能量限饲对肉鸡PPP1R3C表达的影响；试验四，D7雌性肉鸡随机分为3组，对照组、15%能量限饲组和15%蛋白限饲组（n=10），分别饲养至D21屠宰取样，探究能量限饲是否具有剂量依赖性。结果表明：1）PPP1R3C在胸肌组织中高表达，其次是心和腿肌组织（P<0.05）。2）PPP1R3C表达量呈现了明显随鸡发育而升高的趋势。3） INS注射显著下调了胸肌中PPP1R3C的表达，在注射后120 min时PPP1R3C的表达显著低于0和15 min （P<0.05）；PBS注射后胸肌中PPP1R3C的表达没有显著差异，在注射后120和240 min时，INS组PPP1R3C表达显著低于PBS组（P<0.05）。INS注射也降低了肝中PPP1R3C的表达，在INS处理15 min时PPP1R3C的表达已显著低于0 min （P<0.05）；PBS注射后肝中PPP1R3C表达处于动态平衡，在注射后120 min时，INS组PPP1R3C表达显著低于PBS组（P<0.05）。胰岛素注射后在腹脂中出现了与胸肌和肝相反的结果，在胰岛素注射后15 min时PPP1R3C的表达显著高于0、120、和240 min （P<0.05），而0、120、和240 min之间没有显著差异；PBS注射后腹脂中PPP1R3C表达没有显著变化，在注射后15 min时，INS组PPP1R3C表达量显著高于PBS组（P<0.05）。4）30%能量限饲导致PPP1R3C在胸肌和肝中的表达均显著下调（P<0.05）。5）15%能量限饲和15%蛋白限饲不能显著影响胸肌中PPP1R3C的表达。以上研究表明，PPP1R3C在胸肌中表达最高，并随着个体发育表达上升，且外源胰岛素对PPP1R3C的表达效应具有明显的组织特异性。30%能量限饲可产生类似于外源胰岛素的效应，且能量限饲存在一定的剂量依赖性，本研究结果为进一步揭示鸡PPP1R3C功能奠定了基础。 相似文献
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马齿苋水提物对热应激小鼠空肠结构及吸收功能的影响 总被引：1，自引：1，他引：0
旨在探讨马齿苋水提物（aqueous extract of Portulaca oleracea L.）对热应激小鼠空肠结构及吸收功能的影响。将40只昆明种小鼠随机分为4组（n=10）：空白对照组（C）、热应激组（HS）、马齿苋水提物组（AEP）、维生素C组（Vc），HS、AEP和Vc组每天于（40±1）℃环境下处理0.5 h，连续热应激6 d后将小鼠转置于室温下给药治疗。给药7 d后眶窦采血，并采集小鼠空肠；测定小鼠血清中D-木糖、葡萄糖含量；HE染色观察空肠组织病理学变化；qRT-PCR法检测空肠黏膜ZO-1、SGLT1及GLUT2 mRNA的相对转录水平。结果显示，与C组比较，HS组小鼠空肠黏膜绒毛高度极显著降低（P<0.01）；血清中D-木糖的含量极显著降低（P<0.01）；空肠黏膜中ZO-1、SGLT1和GLUT2 mRNA的相对转录水平均极显著降低（P<0.01）；与HS组相比，AEP组小鼠空肠绒毛高度极显著提高（P<0.01）；血清中D-木糖及葡萄糖的含量均显著升高（P<0.01或P<0.05）；空肠黏膜中ZO-1、SGLT1和GLUT2 mRNA的相对转录水平均显著升高（P<0.05或P<0.01）。高温处理可导致小鼠空肠黏膜脱落及吸收功能下降，而在给予马齿苋水提物治疗后可通过提高空肠ZO-1 mRNA表达量修复空肠黏膜结构，通过促进空肠黏膜SGLT1和GLUT2 mRNA的转录量改善吸收功能。马齿苋水提物能在一定程度上修复热应激导致小鼠空肠黏膜结构损伤，改善热应激小鼠肠道的吸收能力。 相似文献
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旨在克隆获得牦牛StAR基因编码序列（CDS）并进行生物信息学分析,探究其mRNA组织表达特性。本研究以屠宰场采集的成年母牦牛心、肝、脾、肺、肾、卵巢、输卵管、子宫组织（n=5）,不同年龄（胎牛、1岁、2岁）牦牛的卵巢（n=3）,不同发情周期（卵泡期、黄体期）的牦牛卵巢（n=3）,黄体期黄牛的卵巢（n=3）及实验室冻存的牦牛颗粒细胞为研究材料。以牦牛黄体期卵巢cDNA为模板,用逆转录PCR克隆StAR基因,并使用MEGA7.0和ExPASy-ProtParam等软件分析其生物信息学特性;采用实时荧光定量PCR技术分析牦牛StAR基因组织表达特性。结果发现,StAR基因CDS区长858 bp,编码285个氨基酸,StAR蛋白总体带正电荷,属于碱性亲水稳定蛋白,无跨膜结构及信号肽,主要存在于细胞质和线粒体; StAR基因具有较高的保守性,符合物种进化规律。牦牛StAR基因在卵巢表达水平最高（P<0.01）,且2岁时卵巢表达水平极显著高于胎牛和1岁龄（P<0.01）,黄体期卵巢表达水平极显著高于卵泡期（P<0.01）;黄体期黄牛卵巢中StAR基因的表达量极显著高于牦牛（P<0.01）;在颗粒细胞的体外培养过程中StAR基因表达量逐渐上升,在培养24 h时达到高峰（P<0.01）,随后显著降低。综上所述,StAR基因序列较为保守,在牦牛卵巢组织中表达最高,且表达水平随年龄与卵巢周期而变化,提示StAR基因可能参与牦牛卵巢及黄体功能相关的繁殖调控。 相似文献
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妊娠母猪的各种饲养方法其经济学很少受到养猪业的关注.最常见的妊娠母猪饲养方法是室内单体限位栏.采用这一方法的主要原因是：（1）工作人员可以更加轻松地管理更多母猪的喂食、疫苗接种、配种、单个动物的转移等作业;（2）可以减少母猪间的身体攻击;（3）工作人员可以更容易地控制母猪所需的环境指标;（4）在较小的范围内,可以饲养更多的母猪;（5）由于能更好地控制排便区,母猪的总体卫生状况可得到改善;（6）每头存栏母猪的繁殖性能得到提高. 相似文献
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为了探究藏山羊ATP6和Cytb是否具有潜在的高海拔适应性突变，本研究利用藏山羊（n=157，来自西藏地区的8个群体，海拔高度>3 500 m）与低海拔山羊（n=104，来自欧亚大陆50个群体，海拔高度<1 000 m）两组261条ATP6和Cytb序列，对核苷酸组成、遗传多样性、单倍型网络以及基因突变对蛋白结构域功能影响进行比较分析。结果，在ATP6和Cytb中分别鉴定出33和67个单核苷酸多态性位点（SNPs），其中错义突变均为6个。值得注意的是，ATP6 m.8102A>G（Ile→Met；P=0.000 6）和Cytb m.14794A>G（Thr→Ala；P=0.007 7）是低海拔山羊群体特有的错义突变，由此形成的单倍体H27和Ha36与高原适应性呈显著负相关（H27，P=0.007 0；Ha36，P=0.012 3）。进一步分析推测，这两个突变阻碍了质子跨膜的正常功能，并影响了质子或电子在OXPHOS中的转移，从而导致了低海拔山羊和藏山羊之间呼吸作用效率的差异。本研究通过对线粒体ATP6和Cytb基因编码区多态性到功能的相关分析，初步推测了藏山羊高海拔低氧适应性机制，为高原适应性相关研究提供了一定的见解。 相似文献
9.
1 限位栏对母猪的伤害
1．1缺乏运动引起的伤害
后备母猪配种后就进入限位栏，限制自由运动，强制母猪只能在限位栏内僵硬机械地原地起与卧，使母猪的身体发育受到极大的摧残。8月龄母猪体成熟、性成熟（体质量130kg左右），2．5～3岁时肌肉、骨骼发育成熟（产5胎， 相似文献
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猪群的钙磷代谢紊乱是影响猪场经济效益的长久问题之一。妊娠母猪缺钙易致猪群的生产性能下降,其仔猪出生后的育肥效果又相对较差,进一步造成生产利润的丢失。本文就妊娠母猪发生钙流失对胎猪脂质代谢方面的影响进行了深入地研究。试验将20头健康的7～8胎龄母猪随机分为对照组（control,CON）和低钙组（low-calcium,LCa）,每组10头作生物学重复。按不同钙磷比配置日粮,于母猪妊娠第85天连续饲喂至第114天分娩。仔猪出生后立即采集其血液和肝肾组织样本。运用代谢组学技术分析仔猪代谢通路的变化;生化仪检测血清中的脂类物质;ELISA方法检测脂质代谢指标;荧光定量检测脂质代谢相关基因的表达。结果表明：低钙胁迫主要影响了胎猪的甘油磷脂代谢通路,同时对脂肪酸代谢及棕榈酸的合成等也造成了一定的干扰;仔猪血清中脂类物质的含量无明显变化（P>0.05）;低钙胁迫显著影响了胎猪体内FAS、Visfatin以及Resistin的分泌（P<0.05）;低钙组仔猪肝中SCD、LDLR,肾中SCD、FABP4、HSD17B12以及ABCC4基因的mRNA表达量显著降低（P<0.05）。以上结果提示,妊娠母猪缺钙可致使胎猪脂质代谢受影响,可能会不利于其生长发育。 相似文献
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Carroll JA Gaines AM Spencer JD Allee GL Kattesh HG Roberts MP Zannelli ME 《Domestic animal endocrinology》2003,24(4):341-351
The objective of the present study was to evaluate the potential immunological benefit of adding menhaden fish oil to the diet of weaned pigs. Twenty-four crossbred male pigs were weaned at approximately 18 days of age and placed on a complex nursery diet containing 30% lactose and 7% plasma protein with 6% corn oil as the fat source (Cont, n=12) or with 5% menhaden fish oil and 1% corn oil as the fat source (MFO, n=12) for a period of 15 days. Body weights did not differ (P>0.78) between dietary groups either at the beginning or end of the 15 days feeding period. On day 15, all pigs were non-surgically fitted with an indwelling jugular catheter. On d 16, pigs received an i.v. injection of either saline (n=6/dietary group) or lipopolysaccharide (LPS; 150 μg/kg body weight; n=6/dietary group) and blood samples were collected at 30 min intervals for a period of 5 h. Serum was harvested and stored at −80 °C for analysis of cortisol (CS), corticosteroid-binding globulin (CBG), tumor necrosis factor-alpha (TNF-) and interferon-gamma (IFN-γ). There was no significant effect of diet on basal concentrations (Time 0) of any of the blood parameters analyzed. A Time×Treatment×Diet interaction (P<0.03) was observed for serum CS such that those pigs which consumed the MFO diet followed by LPS treatment had a reduced CS response as compared to the LPS-treated pigs on the Cont diet. A Time×Treatment interaction (P<0.01) was observed for serum CBG such that LPS treatment reduced circulating CBG as compared to the saline-treated pigs. Time×Treatment×Diet interactions were also observed for serum concentrations of TNF- (P=0.084) and IFN-γ (P=0.022) such that both the TNF- and IFN-γ response to the LPS challenge was lower in those pigs receiving the MFO diet as compared to the LPS-treated pigs on the Cont diet. Overall, serum CS was negatively correlated with the CBG response (r=−0.40, P<0.001), however, the strongest negative correlation was observed in the LPS-treated pigs which consumed the MFO diet (r=−0.63, P<0.001). While further studies are needed to evaluate the immunological response of including MFO in the nursery pig diet, the present study demonstrates that supplementation with MFO does indeed alter the immunological response to an LPS challenge. 相似文献
13.
旨在探究lncRNA-6617的生物学特性及其对猪肌内前体脂肪细胞分化的影响，以及初步探究其上游调节机制，为后续深入研究猪肌内脂肪沉积调控机制提供参考依据。本研究以饲养在相同条件下的1、90、180日龄健康马身公猪(n=3)和大白公猪(n=3)为研究对象，利用RNA-seq技术筛选脂肪型猪(马身猪)和瘦肉型猪(大白猪)肌肉特异表达的lncRNAs，并通过生物信息学分析、RT-PCR及Sanger测序鉴定lncRNA-6617生物学特性及其猪组织中的表达特征。在猪肌内前体脂肪细胞中干扰lncRNA-6617，检测lncRNA-6617对肌内脂肪细胞分化能力的影响。随后，检测m6A修饰相关酶在不同品种猪中的表达差异，研究lncRNA-6617的上游调控机制。结果显示，lncRNA-6617位于猪18号染色体，RAMP3基因反义链的第3内含子区域，无蛋白编码能力，主要分布于细胞核; lncRNA-6617在猪所检测各组织中均有表达，背部皮下脂肪中表达量最高，且在马身猪肌肉组织中的表达极显著高于大白猪(P < 0.01);在猪肌内前体脂肪细胞分化过程中，lncRNA-6617表达量呈上升趋势，且在分化第5天表达量达到最高; 干扰lncRNA-6617诱导分化7 d后，分化的成熟脂肪细胞明显减少，成脂关键基因CEBPα、PPARγ和aP2的表达均极显著下调(P < 0.01)。m6A修饰的去甲基化酶FTO在马身猪背最长肌和股二头肌中的表达极显著高于大白猪(P < 0.01)，在腰大肌中的表达显著高于大白猪(P < 0.05)，上游调节因子ZNF217在马身猪肌肉组织中的表达极显著高于大白猪(P < 0.01)，与lncRNA-6617表达模式一致。干扰FTO后，lncRNA-6617的表达极显著下调(P < 0.01)。本研究筛选了在马身猪肌肉组织中显著高表达的lncRNA-6617，并深入研究了lncRNA-6617促进猪肌内前体脂肪细胞分化的功能及其上游调节机制，丰富了脂肪细胞生成的表观调控网络。 相似文献
14.
Kanitz E Otten W Tuchscherer M Manteuffel G 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2003,50(3):132-139
The present study was conducted in order to reveal the effects of prenatal stress on the central stress regulation in domestic pigs by measuring changes in corticosteroid receptor binding and monoamine concentrations in different limbic brain regions. Pregnant sows were subjected to a restraint stress for 5 min daily during the last 5 weeks of gestation. Maternal stress resulted in a significantly higher number of glucocorticoid receptors in the hippocampus, but decreased glucocorticoid receptors in the hypothalamus of the offspring at the first postnatal day. No alterations of hippocampal mineralocorticoid receptors were found. There was also no significant effect of prenatal stress on the brain monoamine concentrations. Prenatally stressed piglets showed lower basal plasma cortisol and increased corticosteroid binding globulin concentrations at the third postnatal day indicating decreased free cortisol concentrations after birth. Morbidity and mortality during the suckling period were significantly increased in prenatally stressed litters, as shown by a higher frequency of diseased and died piglets per litter. In conclusion, the results indicate that in pigs restraint stress during late gestation affects the ontogeny of the foetal neuroendocrine feedback system with consequences for the regulation of the hypothalamo-pituitary-adrenal function and the vitality of the offspring. 相似文献
15.
Curcumin attenuates the effects of transport stress on serum cortisol concentration, hippocampal NO production, and BDNF expression in the pig 总被引：2，自引：0，他引：2
Curcumin, the active component of curcuma longa, has been reported to be effective in alleviating chronic stress-induced disorders in rodents by modulating neuroprotection and neuroendocrine functions of the central nervous system, especially hippocampus. However, it is unclear whether curcumin can attenuate the subacute stress response induced by 2 h of road transport in the pig. Therefore, the present study was designed to identify the changes of serum cortisol concentration, hippocampal nitric oxide (NO) production, and related gene expression in response to 2 h of transport and to explore whether curcumin treatment (8 mg/kg, p.o.) for 21 d before transport may alleviate the stress-induced responses in the hippocampus of pigs. We found that 2 h of transport elevated serum cortisol concentration (P < 0.01), increased hippocampal NO content, and reduced brain-derived neurotrophic factor (BDNF) mRNA expression in pigs not treated with curcumin, whereas these stress responses were all reversed or attenuated in curcumin-treated pigs. In addition, the stress-induced increase in the expression of constitutive nitric oxide synthase (cNOS) and enzyme activities of total NOS, cNOS, and inducible NOS (iNOS) was also reversed or attenuated in curcumin-treated pigs. However, neither transport nor curcumin caused significant alterations in hippocampal expression of 11β-hydroxysteroid dehydrogenase type 1 and type 2 (11β-HSD1 and 2), glucocorticoid and mineralocorticoid receptors (GR and MR), or pro-/anti-apoptotic molecules (Bax-α and Bcl-xL). These results suggest that curcumin can alleviate subacute stress response in pigs through its neuroprotective effects on modulating hippocampal NO production and BDNF expression. 相似文献
16.
试验旨在研究卵巢类固醇生成信号通路中腺苷酸环化酶3（adenylatecyclase 3,ADCY3）、胰岛素样生长因子1（insulin like growth factor 1,IGF1）基因结构变异的遗传多样性及其与香猪母猪繁殖性状的相关性。采用PCR技术对269头香猪进行ADCY3和IGF1基因结构变异研究,利用在线软件计算遗传杂合度（He）、遗传纯合度（Ho）、有效等位基因数（Ne）及多态信息含量（PIC）,并利用单因素方差分析、LSD法分析不同基因型与初产和经产香猪的总产仔数、产活仔数、初生重及乳头数等繁殖性状的关联性。结果显示,2个结构变异ADCY3-I1-sv506和IGF1-I3-sv302在香猪群体中均存在多态性,均有3种基因型：DD、DI和II,2种等位基因：D和I。其中,ADCY3-I1-sv506中DI基因型为优势基因型（0.569）,D为优势等位基因（0.601）;IGF1-I3-sv302中II基因型为优势基因型（0.717）,I为优势等位基因（0.816）。ADCY3-I1-sv506和IGF1-I3-sv302多态信息含量（PIC）均为中度多态（0.25<PIC<0.5）,杂合度分别为0.479和0.300。关联性分析结果发现,ADCY3-I1-sv506位点DD基因型个体的初产和经产母猪总产仔数显著高于II基因型个体（P<0.05）;IGF1-I3-sv302位点II基因型个体的初产、经产母猪总产仔数和经产母猪产活仔数均显著高于DI基因型型个体（P<0.05）。结果表明,2个结构变异位点ADCY3-I1-sv506和IGF1-I3-sv302与香猪母猪的繁殖性能有直接关联,可作为香猪母猪繁殖性能选育的候选分子标记。 相似文献
17.
Impacts of a modified farrowing pen design on sow and litter performances and air quality during two seasons 总被引：1，自引：0，他引：1
The impacts of using a modified farrowing pen (MOD) on the performance of sows and their litters and on ambient air quality over a hot and a cool season were evaluated. Primiparous Yorkshire × Landrace sows farrowed either during the months of February and March (thermoneutralily, TN) or June and July (heat-stress, HS). Temperatures within each season were controlled to 21 and 29 °C, respectively, for TN and HS. Animals from each group were assigned to a standard farrowing crate (STD; TN, n = 17; HS, n = 16) or a MOD pen (TN, n = 19; HS, n = 19). The MOD pen consisted of a STD crate with a 1.5 × 1.6-m comfort zone in the back, equipped with rubber floor mats, a feeder and a nipple waterer. Litter size was standardized to 10 or 11. No creep feed was provided and piglets were weighed weekly. Sows were weighed on days 2 and 22. Feed intake of sows was monitored daily, a milk sample was obtained on day 21 for compositional analyses and jugular blood samples were collected on days 2 and 21 to measure prolactin, IGF-I and urea. Sows consumed less feed (3.4 vs. 4.7 ± 0.1 kg/day, P < 0.001) in a hot than in a cool season and, at 29 °C, sows in MOD pens consumed more feed (3.9 vs. 3.0 ± 0.2 kg/day, P < 0.01) than sows in STD pens. Sow lactation weight loss was greater (− 26.4 vs. − 19.1 ± 1.9 kg, P < 0.05) for sows in STD than MOD pens in a hot season. The reduction in prolactin concentrations from days 2 to 22 of lactation tended to be greater (P = 0.08) in a hot season for sows in STD pens. Concentrations of urea and IGF-I increased as lactation advanced (P < 0.01) and IGF-I was lower for HS compared to TN sows on both days (P < 0.01), whereas urea was greater for HS sows on day 2 only (P < 0.01). Milk DM was less in a hot than in a cool season (P < 0.01). Average piglet weight gain was reduced in a hot compared to a cool season during the second week of lactation (P < 0.05) and this reduction was less in MOD than STD pens during the third week of lactation (P < 0.01). During a hot season, even though not significant, average weight gain of piglets from days 2 to 21 of lactation was reduced by 6.0% in MOD pens compared to 9.7% in STD pens. 相似文献
18.
M. D. Prickett A. M. Latimer R. H. McCusker G. J. Hausman A. K. Prestwood 《Domestic animal endocrinology》1992,9(4):285-296
The effects of a Sarcocystis miescheriana infection on insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding proteins (IGFBPs) were investigated to determine possible mechanisms of growth retardation in growing pigs. Sixteen pigs averaging 14 kg body weight were divided into 4 groups of 4 pigs each and infected either with 0.5, 1.0, or 3.0 × 106 sporocysts of S. miescheriana. Four pigs were retained as non-infected controls; however, they became serologically positive during the course of the infection. Effects also were investigated in 2 groups of 3 pregnant sows. One group was infected with 0.5 × 106 sporocysts and the other group was retained as uninfected controls. Body weights of infected growing pigs were depressed as compared to controls following the acute phase 15 d after infection (dai). Serum concentrations of IGF-I dropped significantly (p < 0.05) during the acute phase of infection in all infected groups of growing pigs. Conversely, the amounts of unsaturated serum IGFBPs were elevated significantly (p < 0.05) during the acute phase of infection. Specifically, serum concentrations of IGFBP-1, IGFBP-2, and IGFBP-4 were elevated at this time, as determined by ligand blot analysis. There was no association between growth factor alterations and tissue damage as measured by serum creatinine kinase and aspartate aminotransferase levels. The extent of effects in growing pigs was related to the amount of the original parasite inoculum.
During the acute phase of infection 2 of 3 pregnant sows aborted. The third sow went to term, but piglets were stillborn or died within 24 hr. Compared to uninfected controls, serum concentrations of IGF-I in infected pregnant sows were depressed during and after the acute phase of the infection. Levels of unsaturated serum IGFBPs in pregnant sows were not affected.
These data suggest that decreased IGF-I levels and/or elevated levels of specific forms of IGFBPs may be a mechanism by which growth is affected in feeder pigs infected with S. miescheriana. 相似文献
19.
T. Thymann C. Gudbergsen S. Bresson N.B. Kristensen C.F. Hansen 《Livestock Science》2007,108(1-3):132-136
Suckling pigs were separated from their dam for 24 h on day 21 (1 × 24 h fasting, n = 10) or day 21 and 24 (2 × 24 h fasting, n = 10). Pigs in the control group (n = 10) were not fasted before weaning. All pigs were weaned on day 28 postpartum. Feed intake during the first 4 days post-weaning was higher (P < 0.05) for pigs exposed to 1 × 24 h fasting compared with controls. Water consumption was not affected by fasting prior to weaning. The difference in post-weaning feed uptake was not reflected in any clinical traits, intestinal morphology, or activity of digestive enzymes (maltase, dipeptidylpeptidase IV, aminopeptidases A and N; P > 0.15). In conclusion, a short period of fasting prior to weaning can increase post-weaning feed uptake, although this had no clinical impact under the present experimental conditions. 相似文献