【作者】 杨善军；

【导师】 梁学武；

【作者基本信息】 福建农林大学 ， 动物遗传育种与繁殖， 2003， 硕士

【摘要】 本研究分为两个试验。第一个试验选四头装有永久瘤胃瘘管的丹麦红杂交牛，研究棕榈酸对瘤胃内环境的影响，并利用尼龙袋法研究棕榈酸对日粮的干物质（DM）、有机物（OM）、中性洗涤纤维（NDF）、纤维素（CEL）及酸性洗涤木质素（ADL）瘤胃降解率的影响。试验采用4×4拉丁方设计。结果表明：1.5％组、3.0％组及4.5％组的纤毛虫活力沉淀试验的时间比对照组分别延长11.39％（P＜0.05）、26.77％（P＜0.01）及32.46％（P＜0.01）；瘤胃液的pH值分别升高1.75％（P＜0.05）、2.71％（P＜0.05）及4.30％（P＜0.05）；Ca²⁺、Mg²⁺、NH₃-N、总挥发性脂肪酸（TVFA）及乙酸浓度分别下降9.51％（P＞0.05）、26.32％（P＞0.05）、28.83％（P＜0.05）；5.52％（P＞0.05）、22.81％（P＜0.01）、24.54％（P＜0.01）；3.28％（P＜0.05）、23.03％（P＜0.01）、24.02％（P＜0.01）；3.28％（P＜0.05）、23.03％（P＜0.05）、24.02％（P＜0.01）及11.61％（P＞0.05）、21.41％（P＜0.05）、23.97％（P＜0.05）。棕榈酸对丙酸浓度的影响差异不显著（P＞0.05），丁酸浓度4.5％组下降24.67％（P＜0.05），1.5％组、3.0％组差异不显著（P＞0.05）。随着棕榈酸添加水平的提高，虽然DM、OM、NDF、CEL及ADL的瘤胃降解率有呈线性下降的趋势，但差异均不显著（P＞0.05）。 第二个试验选用32头荷斯坦奶牛，根据产奶量、胎次、泌乳天数进行配对，共配成4组，每组8头，研究棕榈酸对奶牛生产性能（产奶量、乳脂率、乳蛋白率、乳总固体率）、干物质进食量（DMI）、血液生化指标（血糖、血钙、血镁）及OM、粗蛋白（CP）、NDF、粗脂肪（EE）全消化道表观消化率的影响。结果表明：1.5％组、3.0％组及4.5％组DMI比对照组分别下降2.04％、6.12％及10.44％；产奶量呈线性下降趋势，但差异不显著（P＞0.05）；添加棕榈酸可提高乳蛋白含量，其中3.0％组及4.5％组乳蛋白率较对照组分别提高4.03％（P＜0.05）及3.89％（P＜0.05），但对乳脂率和乳总固体率影响差异不显著（P＞0.05）；血糖、血钙的浓度有下降的趋势，血镁的浓度有升高的趋势，但差异均不显著（P＞0.05）。1.5％组、3.0％组及4.5％组OM、CP及NDF的表观消化率分别比对照组下降1.91％（P＞0.05）、2.16％（P＜0.05）、2.74％（P＜0.01）；0.26％（P＞0.05）、0.95％（P＞0.05）、2.01％（P＜0.05）及0.99％（P＞0.05）、4.15％（P＞0.05）、8.50％（P＜0.05）；EE的表观消化率分别提高2.69％（P＞0.05）、3.44％（P＜0.05）及3.55％（P<0 .05）。更多还原

【Abstract】 Two experiments were conducted for studying the effects of palm acid on the ruminal environment and the performance of dairy cows.Experiment l.Four hybrid steers fitted with permanent cannula were used with a 4X4 Latin-square design to study the effects of palm acid on the ruminal environment and to measure the effective degradability of dry matter(DM), organic matter (OM), neutral detergent fiber (NDF), cellulose (CEL) and acid detergent lignin (ADL) by nylon bags method (in situ). Palm acid was added at 0, 1.5%, 3.0% and 4.5%, respectively to the diet of the steers, and 0 group was regarded as control group. The results were as follows: Compare to control group, the deposit time of testing activity of protozoa of 1.5%, 3.0%, 4.5% groups were prolonged by 11.39% (P<0.05)> 26.77% (P<0.01)and 32.46% (P <0.01),respectively The value of pH were increased by 1.75% (P<0.05)> 2.71% (P<0.05) and 4.31% (P<0.05), respectively. The concentrates of calcium ion were decreased by 9.51% (P>0.05), 26.32% (P>0.05) and 28.83% (P<0.05), respectively, and magnesium ion were decreased by 5.52% (P> 0.05), 22.81% (P<0.01), 24.54% (P<0.01), respectively. The concentrate of NH3-N were decreased by 3.28% (P<0.05)> 23.03% (P<0.01)and 24.02% (P <0.01), respectively. TVFA were decreased by 3.28% (P<0.05)> 23.03% (P< 0.05)and 24.02% (P<0.01), respectively, and acetic acid were decreased by 11.61% (P>0.05), 21.41% (P<0.05)and 23.97% (P<0.05), respectively. The effect of palm acid on the concentrate of propionic acid was not significant (P> 0.05). The concentrate of butyric acid were increased by 24.67% (P<0.05 ) for 4.5% group, but not significant for the other groups. The effective degradability ofDM> OM> NDF> CEL and ADL declined with line-trend, but the difference was not significant between treatment groups and contrail group.Experiment 2. 32 China Holsteins were allotted randomly into four groups of eight heads each, one was controll group, and the others were treatment groups. The cows were grouped according to the milk production, parity, and lactation days to study the effects of palm acid on the performance (milk production, milk fat percentage, milk protein percentage, total solid percentage) , dry matter intake (DMI) , blood biochemical parameters (the concentration of glucose, calcium and magnesium in serum) and apparent digestibility in total enteron of OM,crude protein (CP),NDF, ether extract (EE).The results were as follows: Compare to control group, DMI were decreased by 2.04%> 6.12% and 10.44%, respectively, and milk production were decreased by 3.21%% 4.05% and 5.32%, respectively, but not significant. The differences of milk fat percentage and milk solid percentage were not significant among four groups. Milk protein percentage of 3.0%, 4.5% groups were increased by 4.03% (P<0.05) and 3.89% (P<0.05) than control group, but there was no significant difference between 1.5%-group and control group. The glucose and calcium in blood had decreasing trend, but magnesium had increasing trend, and the differences were not significant for above blood biochemical parameters. Compare to control group, the apparent digestibilities of OM were decreased by 1.91% (P>0.05), 2.16% (P<0.05)and 2.74% (P<0.01), respectively; and CP were decreased by 0.26% (P>0.05)> 0.95% (P>0.05)and 2.01%(P<0.05), respectively; and NDF were decreased by 1.61% (P>0.05), 4.76% (P>0.05) and 9.13% (P<0.05), respectively; and EE were increased by 2.69% (P>0.05)> 3.44% (P<0.05) and 3.55% (P<0.05), respectively.更多还原