共查询到17条相似文献，搜索用时 187 毫秒
1.
为了研究长期或短期饲喂高精料日粮对泌乳期奶山羊瘤胃上皮组织氧化应激和胆固醇代谢的影响,实验选用17只健康的经产泌乳中期关中奶山羊,随机分为3组:饲喂低精料组(对照组,LC,n=5);长期饲喂高精料组(HL, n=7),19周饲喂期;短期饲喂高精料组(HS,n=5),4周饲喂期。实验结束后采集瘤胃组织,用PBS反复清洗,于液氮中速冻后置于-80 ℃冰箱保存。结果显示,与对照组相比,HL和HS组山羊瘤胃上皮组织中细胞周期相关基因CDK2和CDK4 mRNA表达水平显著升高(P<0.05),且HS组p-ERK1/2蛋白表达显著升高(P<0.05),但GPR41和GPR43蛋白表达无显著变化(P>0.05);HL和HS组山羊瘤胃上皮组织促细胞凋亡基因Casepase9 mRNA表达显著升高(P<0.05),HS组抗凋亡Bcl-2/Bax mRNA表达比例呈下降趋势(0.050.05);HS组瘤胃上皮组织中胆固醇含量下降达显著水平(P<0.05),且HL组呈下降趋势(0.05+ ATPase mRNA表达显著升高(P<0.05),NHE2蛋白表达升高但未达显著差异水平(P>0.05)。与HL组相比,HS组山羊瘤胃上皮组织中总抗氧化能力T-AOC显著升高(P<0.05);且胆固醇含量显著下降(P<0.05)。以上结果说明,短期饲喂高精料日粮可加快泌乳期奶山羊瘤胃上皮组织的更新,提高组织总抗氧化能力;而长期饲喂高精料日粮未引起细胞增殖相关蛋白和总抗氧化能力的显著变化;饲喂高精料日粮可以加快瘤胃上皮组织对VFA的转运。此外,饲喂高精料日粮引起瘤胃上皮组织内胆固醇含量降低,胆固醇酰基转移酶基因表达的显著上调,提示其对瘤胃上皮组织更新的潜在影响。 相似文献
2.
为了研究饲喂高精料日粮对泌乳期山羊肝脏糖脂代谢的影响,试验选用16只健康经产泌乳中期关中奶山羊,随机分为3组,低精料组(LC, n=5)、长期高精料组(HL, n=7)和短期高精料组(HS, n=4)。实验结束后采集血液和肝脏组织。结果显示,与LC组相比,HL和HS组奶山羊血糖和肝糖原水平显著升高(P<0.05),血液中甘油三酯(TG)水平显著降低(P<0.05),胆固醇(Tch)含量没有显著变化(P>0.05);HS组山羊肝脏TG和Tch水平显著增加(P<0.05),HL组无显著变化 (P>0.05)。HL组肝脏中丙酮酸羧化酶(PC)和葡萄糖转运蛋白2(GLUT2)mRNA表达水平显著上调;HS组肝脏PC、固醇调节元件结合蛋白1(SREBP1)、硬脂酰辅酶A去饱和酶(SCD)、二酰基甘油酰基转移酶(DGAT)和3-羟基-3-甲基戊二酰辅酶A还原酶(HMGCR) mRNA表达水平显著升高(P<0.05),SREBP-2有升高的趋势(P=0.76),肉碱棕榈酰转移酶-1(CPT-1)和胆固醇7α-羟化酶(CYP7α1)mRNA表达显著下降(P<0.05);线粒体型磷酸烯醇式丙酮酸羧激酶(PCK2)蛋白表达水平显著升高(P<0.05)。以上结果表明,短期饲喂高精料日粮能增强肝脏糖异生能力,促进肝脏胆固醇和脂肪合成;而长期饲喂高精料日粮能增强肝脏糖异生作用,但对胆固醇和脂肪代谢相关基因的表达没有影响。 相似文献
3.
《畜牧与兽医》2017,(9):101-106
本试验旨在研究高精料日粮对奶山羊乳腺组织NOD1炎性信号通路的影响与调控。选取18头泌乳中期的健康萨能奶山羊,试验前分别安装瘤胃瘘管和乳静脉血管插管,随机分成3组:饲喂精粗比为4∶6的低精料日粮作为对照组(LC);饲喂精粗比为6∶4的高精料日粮作为处理组(HC);饲喂高精料日粮并添加丁酸钠作为调控组(BHC),试验时间为20周。试验结束后采集瘤胃液、乳静脉血和乳腺组织样品用于后续的瘤胃pH值、乳静脉血中炎性因子浓度、乳腺组织中炎症相关基因m RNA和蛋白水平的检测。结果显示:一天内HC组的瘤胃pH值小于5.8持续4 h且显著低于LC组,表明亚急性瘤胃酸中毒(SARA)诱导成功;饲喂4 h后BHC组瘤胃pH值显著高于HC组而与LC组差异不显著,表明丁酸钠能够缓解瘤胃pH的持续降低。HC组乳静脉血中炎性细胞因子IL-1β、IL-6和TNF-α的浓度显著高于LC组,而BHC组的炎性细胞因子溶度显著低于HC组并与LC组无显著差异;与LC组和BHC组相比,HC组奶山羊乳腺组织炎症相关基因NOD1、RIP2、NF-κB、IL-1β、IL-6的表达量显著上调;NOD1、NF-κBp65、NF-κBpp65的蛋白表达水平和m RNA水平变化一致。结果表明,长期饲喂高精料日粮能够激活奶山羊乳腺组织的NOD1-NF-κB炎性信号通路,诱导乳腺炎症应答,日粮中添加丁酸钠可以一定程度地缓解乳腺组织的炎症反应。 相似文献
4.
为了研究长期饲喂高精料日粮对泌乳期山羊血液生化指标和糖代谢的影响,选择8只安装永久性瘤胃瘘管的健康经产泌乳中期山羊,分别饲喂精粗比为40∶60 (low concentrate, LC,n=4) 和60∶40 (high concentrate, HC,n=4)的日粮。实验期共8周,实验期间采集瘤胃液,血液;实验结束时采集肝脏,肌肉,脂肪组织置于液氮速冻后于-70℃保存待测。结果显示,饲喂高精料日粮2周后山羊瘤胃液pH显著降低,采食后瘤胃液pH持续低于5.8超过3 h,8周后瘤胃液pH升高维持在6.0以上,但仍低于LC组山羊。与LC组山羊相比较,HC组山羊血液中葡萄糖、游离脂肪酸含量均升高(P<0.05,P=0.071),谷草转氨酶含量有上升的趋势(0.05相似文献
5.
《畜牧与兽医》2017,(9):111-116
本试验旨在研究饲喂高精料日粮以及日粮中添加丁酸钠对奶山羊乳腺内组胺介导的炎症反应的影响。选用泌乳中期的18头萨能奶山羊,随机分成3组,每组各6头。对照组(LC)饲喂粗精比为6∶4的低精料日粮,即日粮包括60%粗料和40%精料;试验一组(HC)饲喂粗精比为4∶6的高精料日粮,即日粮包括40%粗料和60%精料;试验二组(BHC)饲喂粗精比为4∶6的高精料日粮,并在日粮中添加20 g丁酸钠。试验期为20周。试验开始前两周,所有试验动物手术安装瘤胃瘘管。试验第20周采集瘤胃液、外周血液和乳腺组织样品。结果显示:与LC组相比,HC组瘤胃液、外周血液、乳腺组织中的组胺含量显著升高,外周血液中的炎性因子IL-1β、IL-6和TNF-α显著升高,乳腺组织中的组胺受体基因表达显著升高,炎性因子在基因和蛋白表达水平上均显著升高。与HC组相比,BHC组瘤胃液、外周血液、乳腺组织中的组胺含量显著下降,外周血液中的炎性因子均显著降低,乳腺组织中的组胺受体基因表达显著降低,炎性因子的基因和蛋白表达显著下降。结果表明:泌乳奶山羊长期饲喂高精料日粮后,瘤胃产生的组胺经消化道吸收并转运到乳腺组织中,刺激炎症的产生;而通过添喂丁酸钠,组胺和炎性因子的产生显著降低,乳腺组织炎症反应减轻。 相似文献
6.
本实验旨在探究饲喂高精料日粮对山羊瘤胃和盲肠发酵、生物胺生成与吸收的影响研究。试验选用6头装有永久性瘤胃瘘管的雄性波杂山羊,随机分成低精料组与高精料组,实验期24 d。结果显示,与低精料组相比,饲喂高精料日粮的山羊瘤胃液中总挥发性脂肪酸、乙酸、丙酸、丁酸、戊酸、总支链脂肪酸、酪胺、腐胺、组胺、甲胺和色胺浓度显著性增加(P<0.05),而瘤胃pH和乙丙比显著降低(P<0.05);饲喂高精料日粮的山羊盲肠内容物中的乙酸、丙酸、总挥发性脂肪酸浓度和上述5种生物胺浓度显著增加(P<0.05);同时,瘤胃和盲肠静脉血中的上述5种生物胺的浓度显著提高(P<0.05)。相关性分析结果表明,瘤胃液中酪胺、腐胺、甲胺和色胺浓度与瘤胃静脉血所对应的生物胺浓度呈显著正相关(P<0.05),且盲肠内容物中酪胺、腐胺、甲胺和色胺与盲肠静脉血中对应的生物胺的浓度呈显著正相关(P<0.05)。结果说明,饲喂高精料日粮促进了山羊瘤胃和盲肠发酵,提高了瘤胃与盲肠内容物中生物胺浓度,暗示高精料日粮可能提高消化道上皮的通透性,促进消化道上皮对生物胺的吸收。 相似文献
7.
为了研究不同精粗比全混合日粮对山羊肉品质、血清指标和器官发育的影响,将体重相近、健康的4月龄努比亚黑山羊36只随机分为3组,每组12只羊。试验组山羊分别饲喂低精粗比(40∶60,L)、中精粗比(50∶50,M)和高精粗比(60∶40,H)全混合日粮,试验为期70 d。结果表明:1)不同精粗比日粮对整个试验期山羊的体尺指标无显著影响(P>0.05)。2)正试期第14天,H组山羊血清谷草转氨酶(aspartate aminotransferase,AST)、谷丙转氨酶(alanine aminotransferase,ALT)和肌酸激酶(creatine kinase,CK)活性显著低于L组(P<0.05);正试期第56天,H组山羊血清AST/ALT值显著高于L组(P<0.05),但碱性磷酸酶(alkaline phosphatase,ALP)活性则相反。3)H组山羊肌肉失水率显著低于其他两组(P<0.05),但肌肉pH则相反;M组肌肉红度显著低于其他两组(P<0.05),各组间其他项目无显著性差异(P>0.05)。4)L组山羊的瘤胃重量、肝脏重量和肝脏指数显著高于H组(P<0.05),而肺指数则相反;M组山羊网胃重量、网胃指数、瓣胃重量、瓣胃指数和皱胃指数著高于L组(P<0.05),而脾脏重量和脾脏指数则相反。5)L组山羊十二指肠绒毛高度、VH/CD和空肠VH/CD显著高于H组(P<0.05),而空肠的隐窝深度则相反;M组山羊回肠绒毛高度和VH/CD显著高于H组(P<0.05)。综上所述,低精粗比日粮能够促进努比亚山羊胃肠道发育,高精粗比日粮能够提高山羊肉品质。从本试验结果来看,采用低精粗比(40∶60)日粮对努比亚山羊进行育肥较好。 相似文献
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在研究不同比例全株玉米青贮、谷草和羊草组合日粮饲喂干奶前期奶牛对其围产期生产性能和血液生化及免疫指标的影响。选择健康、体况一致的干奶前期荷斯坦奶牛45头,根据体重、胎次及预产期接近(P>0.05)的原则将奶牛随机分为试验A、B和C组,每组15头。分别以精料、全株玉米青贮、谷草和羊草16∶24∶30∶30(A组)、16∶24∶45∶15(B组)和16∶24∶60∶0(C组)比例配合日粮饲喂。产前2周将3组试验牛转入围产牛群,3个试验组开始饲喂场内同一围产前期和新产牛日粮。试验期88 d。结果表明:1)与C组相比,B组在产后1、2和3周的干物质采食量分别提高10.46%(P<0.05)、7.79%(P<0.05)和5.65%(P<0.05)。除产后1周外,产后2、3周B组的奶牛体况评分分别比C组高6.60%(P<0.05)和9.06%(P<0.05)。2)各试验组的犊牛初生重差异不显著(P>0.05)。试验A、B组初乳免疫球蛋白G(IgG)含量分别比C组提高10.82%(P<0.01)和18.07%(P<0.01)。3)与C组相比,B组产后21 d产奶量提高9.00%(P<0.05),乳非脂固形物率提高2.83%(P<0.05),乳蛋白率提高10.59%(P<0.05),乳糖率提高5.64%(P<0.05)。各试验组间乳脂率和尿素氮无显著差异(P>0.05)。4)分娩当天和产后21 d,B组的血清甘油三酯含量显著低于A和C组(P<0.05),B组的血糖含量显著高于A和C组(P<0.05), B组的血清尿素氮和胰岛素显著低于C组(P<0.05),B组的胰岛素样生长因子I(IGF-I)和总蛋白显著高于C组(P<0.05);在产前7 d和分娩当天,B组的血清免疫球蛋白A(IgA)、免疫球蛋白B(IgM)和IgG显著高于C组(P<0.05);在产后21 d,B组的血清IgM和IgG含量显著高于C组(P<0.05);产前7 d和分娩当天,B组瘦素显著高于C组,而B组的血清非酯化脂肪酸(NEFA)含量显著低于C组(P<0.05);在产前7 d、分娩当天和产后21 d,B组的胆固醇均显著低于C组(P<0.05),B组的血清白蛋白含量显著高于C组,B组谷草转氨酶(AST)和谷丙转氨酶(ALT)也显著低于C组(P<0.05)。各试验组间β-羟丁酸无显著差异(P>0.05)。综合分析,干奶前期饲粮组成和养分水平可影响围产期奶牛的机体代谢和生产性能。在本试验条件下,干奶前期奶牛日粮中精料、全株玉米青贮、谷草和羊草的适宜比例为16∶24∶45∶15。 相似文献
9.
本研究旨在探讨过瘤胃谷氨酰胺对饲喂高精料的奶山羊瘤胃上皮屏障的保护效应。实验采用随机区组设计,将12头健康奶山羊随机分为高精料组(n=6)和高精料添加谷氨酰胺组(n=6),谷氨酰胺添加量为50 g/(d·头)。谷氨酰胺处理4周后,每组各选取4头山羊进行屠宰。HE染色、扫描和透射电镜法观察瘤胃上皮的组织形态学变化,实时荧光定量 PCR 法检测瘤胃上皮炎症因子及紧密连接蛋白mRNA的相对表达水平。结果表明,与对照组相比,添加谷氨酰胺显著降低了瘤胃液中丙酸浓度(P<0.01),有降低瘤胃乳酸、提高丁酸浓度的趋势,但对瘤胃液pH、乙酸、异丁酸、总挥发性脂肪酸浓度无显著影响(P>0.05);对组织形态的观察结果表明,添加过瘤胃谷氨酰胺可维持瘤胃复层扁平上皮各细胞层的完整性,保护角质层,减少细胞凋亡;并显著降低瘤胃上皮组织中TNF-α的mRNA相对表达量(P<0.05),显著提高occludin的mRNA相对表达量(P<0.05);但对IFN-γ、IL-1β、IL-6、IL-10、claudin-1、claudin-4和ZO-1 mRNA表达量无显著影响(P>0.05)。结果说明,高精料日粮下添加过瘤胃谷氨酰胺可降低瘤胃上皮的炎症反应,改善上皮紧密连接,从而维护瘤胃上皮屏障的正常功能。 相似文献
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[目的]为研究中药复方对泌乳牛生产性能和瘤胃发酵参数的影响。[方法]选取40 头泌乳牛随机分为四组,即对照组、试验Ⅰ、Ⅱ、Ⅲ组,对照组奶牛饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组在基础日粮中分别添加100 g/d、200 g/d、300 g/d中药复方。预试期7 天后连续饲喂30 天,试验期结束时检测生产性能指标和瘤胃发酵参数。[结果]与对照组相比,试验Ⅰ、Ⅱ、Ⅲ组平均日增重、平均日采食量显著提高（P<0.05）,料重比显著降低（P<0.05）;产奶量、4%标准乳产量及所产牛奶中的乳脂率显著升高（P<0.05）,体细胞数显著降低（P<0.05）;奶牛瘤胃液pH显著降低,总挥发性脂肪酸显著升高（P<0.05）。[结论]中药复方提高了泌乳牛的生产性能,改善了瘤胃发酵情况。 相似文献
11.
Ping Tian Yanwen Luo Xian Li Jing Tian Shiyu Tao Canfeng Hua Yali Geng Yingdong Ni Ruqian Zhao 《畜牧与生物技术杂志(英文版)》2018,(1)
Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet(35% concentrate, n = 5, LC) and there were two high-concentrate treatments(65% concentrate, HC), one fed a high concentrate diet for a long period(19 wks, n = 7, HL); one fed a high concentrate diet for a short period of time(4 wk, n = 5, HS). Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results: Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet(P 0.01), while the percentage of milk fat was lower in the HL(P 0.05) but not in the HS group. The total amount of saturated fatty acids(SFA) in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids(UFA) and monounsaturated fatty acids(MUFA) were markedly decreased in the HL group compared with the LC group(P 0.05). Among these fatty acids, the concentrations of C15:0(P 0.01), C17:0(P 0.01), C17:1(P 0.01), C18:1 n-9 c(P 0.05), C18:3 n-3 r(P 0.01) and C20:0(P 0.01) were markedly lower in the HL group, and the concentrations of C20:0(P 0.05) and C18:3 n-3 r(P 0.01) were lower in the HS group compared with the LC group. However, the concentrations of C18:2 n-6 c(P 0.05) and C20:4 n-6(P 0.05) in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group(P 0.05), and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group(P 0.05). In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group(P 0.05). The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group(P 0.05).Conclusions: Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods. 相似文献
12.
不同精粗比日粮对奶山羊瘤胃液pH值、VFA及血液VFA含量的影响 总被引：2，自引：0，他引：2
本试验旨在探讨不同精粗比日粮对奶山羊瘤胃液pH值、VFA以及血液中VFA含量的影响。选择8只安装永久性瘤胃瘘管的奶山羊作为试验动物,采用完全随机分组试验设计随机分为2组,分别饲喂精粗比为6∶4和4∶6的日粮,预饲期15 d,采样期3 d。结果表明,高精料组(HC组)瘤胃液pH值显著低于低精料组(HR组)(P<0.05);在采食后3 h,HC组与HR组瘤胃液pH值均下降至最低值,分别为5.71和6.08。除了乙酸含量外,HC组瘤胃液丙酸、异丁酸、丁酸、异戊酸、戊酸以及总挥发性脂肪酸(TVFA)含量分别比HR组提高4.99%、5.58%、21.81%、17.95%、18.27%、1.66%。HC组血浆中各种VFA的含量均高于HR组,其中丙酸、丁酸含量两组间差异达到显著水平(P<0.05)。HC组瘤胃液以及血浆中乙酸与丙酸比值均低于HR组,但两组间差异均不显著(P>0.05)。HC组瘤胃液乙酸、丙酸、TVFA浓度在采食后2 h达到最大值,HR组在采食后3 h达到最大值,两组日粮血浆中VFA浓度均在采食后2 h达到最大值,然后逐渐恢复到采食前水平。结论:高精料日粮导致瘤胃液pH值显著降低,瘤胃液和血浆中VFA含量增加;瘤胃液VFA生成速率HC组高于HR组。 相似文献
13.
选择7只装有永久性瘤胃瘘管的泌乳中期山羊,2×2拉丁方设计,分别饲喂精粗比为6∶4和4∶6的饲料,通过饲喂精粗比6∶4饲料建立泌乳期山羊瘤胃亚急性酸中毒(subacute ruminal acidosis, SARA)模型,研究SARA时山羊血液和瘤胃液中皮质醇浓度、肝脏皮质醇受体(glucocorticoid receptor, GR)mRNA表达及其他相关指标的变化。结果表明,精粗比6∶4日粮饲喂2周后成功诱导SARA状态(SARA组),采食后瘤胃液pH值低于5.8持续时间约6 h,而精粗比为4∶6组山羊瘤胃液pH均高于6.0 (对照组)。高精料日粮处理对瘤胃pH和乳酸以及瘤胃液和血浆内的脂多糖、皮质醇浓度有显著性影响(P<0.05),采食前SARA组山羊瘤胃液中乳酸浓度显著高于对照组(P<0.05),采食后0~4 h乳酸含量下降,6~10 h时逐渐增加并极显著高于对照组(P<0.01);2组间瘤胃液中脂多糖浓度无显著性差异(P>0.05),SARA组血浆脂多糖浓度在采食前和采食后6 h均显著高于对照组(P<0.05);采食前SARA组山羊血液中皮质醇浓度高于对照组(P=0.05),但采食后6 h两组间无显著差异(P>0.05); 2组山羊瘤胃液中皮质醇浓度在采食后2,4和6 h分别显著高于对照组(P<0.05),但在采食前和采食后10 h无显著差异(P>0.05)。Real-time PCR结果显示,SARA组山羊肝脏中GR mRNA表达显著下调(P<0.05)。本研究结果显示,泌乳期山羊发生SARA时糖皮质激素水平升高,负反馈下调肝脏GR的表达水平,提示SARA时机体处于应激状态,可能引起肝脏的物质代谢和营养物质重分配的改变。 相似文献
14.
Three rumen fistulated wethers consumed a roughage (1200 g artificially dried grass) or a concentrate/roughage diet (600 g concentrate, 400 g dried grass per animal and day). The diets were unsupplemented or 0.5, 1 or 2 g choline per animal and day were added. After a 14-day feeding period, samples of rumen liquid were taken 0, 1, 2, 3, 4 and 6 h after morning feeding. In a second experiment, untreated and ammonia-treated wheat straw were incubated in nylon bags for 6, 12, 24, 48 and 72 h in rumen of 5 sheep fed on 1.2 kg dried grass and without or with 1 g choline per day. Choline supplementation decreased the total concentration of volatile fatty acids in rumen liquid in both types of diet (roughage: 106, 83, 89 and 87; concentrate/roughage: 142, 114, 91 and 106 mmol/l for 0, 0.5, 1 and 2 g choline per day resp.). Concentration of acetate and branched chain fatty acids in both diets and butyrate in concentrate/roughage diet was reduced as total acids. Butyrate in roughage diet was increased by added choline. Molar propionate concentration was not significantly influenced by choline (P greater than 0.05). Choline resulted in a little increase (P greater than 0.05) of dry matter degradability in rumen, especially when NH3-treated straw was incubated. The effect of choline on milk fat production of cows fed with diets rich in concentrate is probably not related to changes in rumen fermentation and digestion. 相似文献
15.
Impact of diet composition and temperature–humidity index on water and dry matter intake of high‐yielding dairy cows 
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下载免费PDF全文 S. Ammer C. Lambertz D. von Soosten K. Zimmer U. Meyer S. Dänicke M. Gauly 《Journal of animal physiology and animal nutrition》2018,102(1):103-113
The temperature–humidity index (THI) is widely used to characterize heat stress in dairy cattle. Diet composition is known to induce variation in metabolic‐associated heat production. However, the relationships between THI and diet are poorly characterized with regard to performance and intake behaviour. Therefore, the objectives were to evaluate the impact of THI on water intake (WI), dry matter intake (DMI) and the frequency of drinking and feeding bouts in lactating dairy cows offered four dietary treatments: each contained 20% grass silage and additionally (i) 20% maize silage, 60% concentrate (M‐HC); (ii) 60% maize silage, 20% concentrate (M‐LC); (iii) 20% pressed beet pulp silage, 60% concentrate (BPS‐HC); or (iv) 60% pressed beet pulp silage, 20% concentrate (BPS‐LC) (DM basis). Individual WI and DMI were recorded from April to July 2013. Furthermore, dietary effects on milk production and reticular pH were estimated. Milk yield was lowest for M‐LC, while energy‐corrected milk was similar for all diets. Milk fat percentage was higher and milk protein amount lower for cows offered both LC diets. Reticular pH below 6.3, 6.0 and 5.8 lasted longest for BPS‐LC. WI was higher for HC diets. However, the frequency of drinking bouts was not influenced by the ration. Lower DMI occurred for BPS‐LC compared to M‐LC. Frequency of feeding bouts was significantly higher for LC diets. THI was significantly related to WI, DMI as well as drinking and feeding bouts. Per increasing THI, WI increased slightly more for LC diets and DMI decreased more for HC diets. Frequency of drinking bouts increased slightly higher for BPS rations per rising THI, while the decrease in feeding bouts was highest for M‐HC. In conclusion, TMR composition and moderate heat stress impacted WI and DMI of dairy cows, while both dietary energy density and ruminal filling might intensify the THI impact. 相似文献
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Huaibao Zhao Jinye Lu Zhinan Huang Lei Yan Martens Holger Zanming Shen 《Animal Science Journal》2014,85(6):660-670
The hypothesis that different concentrate : forage ratio diets alter omasal epithelium proliferation of growing goats via cyclins and regulation of the cell cycle was tested. Growing goats were fed with a high concentrate (HC, n = 8) or a low concentrate (LC, n = 8) diet for 42 days. The concentrate : forage ratio was 40:60 in the HC group and 0:100 in the LC group. In the HC group, the relative weight and DNA content of the omasal epithelium were lower, but the protein : DNA ratio was higher. Flow cytometry revealed that HC omasal cell numbers were smaller in S‐ and G2/M‐phases of the cell cycle and higher in the G0/G1‐phases and were accompanied by reduced expression of cyclin D1 and CDK4 mRNA and protein. These data are consistent with morphologic observations in the HC that cell density decreased in the stratum spinosum (SS) plus stratum granulosum (SG) and stratum basale, and that cell density was lower in the SS plus SG. Thus, high‐concentrate : forage ratio diet retards omasal epithelial growth by slowing the G1 to S phase transition of the cell cycle and is associated with decreased cyclin D1 and CDK4 expression in growing goats. 相似文献
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本文旨在研究不同比例青干草与青贮玉米对崂山奶山羊泌乳性能和血清生化指标的影响。选择产奶量为(1.65±0.05)kg/d的崂山奶山羊2胎母羊20只,随机分为4组,粗饲料青干草与青贮玉米比例分别为8∶2(试验Ⅰ组)、6∶4(试验Ⅱ组)、4∶6(试验Ⅲ组)、2∶8(试验Ⅳ组),每组5只。预试期7 d,正试期60 d。结果表明:各组产奶量、干物质采食量和料奶比无显著差异(P0.05)。乳脂含量在第0天、第20天、第40天无显著差异(P0.05),第60天试验Ⅱ组显著高于试验Ⅲ组(P0.05)。试验Ⅱ组的乳蛋白含量平均值显著高于其他各组(P0.05)。试验Ⅱ组和试验Ⅳ组的血清葡萄糖含量均显著高于试验Ⅰ组(P0.05),试验Ⅱ组的血清胆固醇含量为最低值,且显著低于试验Ⅲ组(P0.05)。综合得出,崂山奶山羊粗饲料青干草与青贮玉米以6∶4组合效果最好,乳脂、乳蛋白、乳糖等营养物质含量相对较高,血清中胆固醇含量相对较低。 相似文献