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饲料中不同脂肪酸对草鱼组织脂质含量和脂肪酸构成的影响 总被引:17,自引:1,他引:16
实验选用初始作重约1.4g的草鱼,在60天的饲养期中分别投喂1种不含脂肪的饲料和8种含3%不同脂质的饲料,观察了饲料中添加油酸(18:1n-9)、亚油酸(18:2n-6)、亚麻酸(18:3n-3)和n-3系列高度不饱和脂肪酸(n-3HUFA;20:5n-3+22:6n-3)对草鱼肝胰脏、肌肉、头部和去肝胰脏内脏脂质含量和脂肪酸构成的影响。实验结果表明,与摄食单纯含油酸饲料的草鱼相比,含1%18:2n-6和1%18:3n-3或1%18:2n-6和0.5%n-3HUFA饲料组草鱼的肝胰脏脂质含量显著降低,但内脏脂质含量升高。向饲料中添加18:2n-6、18:3n-3和n-3HUFA能明显影响草鱼肝胰脏、肌肉和头部脂质多不饱和脂肪酸的相对含量;组织中n-6系列和n-3系列高度不饱和脂肪酸含量分别与饲料中添加18:2n-6和18:3n-3有相关关系,表明草鱼具有生物转化18:2n-6和18:3n-3为高度不饱和脂肪酸的能力。 相似文献
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草业作为畜牧业发展的物质基础,在农牧业结构调整中具有重要地位。根据称多县的实际,制定草业发展计划,积极发展草产业,解决天然草地普遍超载过牧,牧草供求不平衡等问题,提高抗御自然灾害的能力。 相似文献
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After the 1998 North 25 Fire in the Wenatchee National Forest, eight study sites were established on steep, severely burned hillslopes to examine the effectiveness of postfire seeding and fertilizing treatments in increasing cover to reduce hillslope erosion, and to measure the nutrient content of the eroded sediment. At each site, four 4 by 9 m plots were located with four randomly applied treatments: seed (winter wheat, Triticum estivum) at 34 kg ha− 1, fertilizer (75% ammonium nitrate and 25% ammonium sulfate) at 31 kg ha− 1, seed and fertilizer, and untreated control. Sediment fences were installed at the base of each plot to measure erosion rates and sample the eroded sediments. In addition, precipitation amounts and intensities, surface cover, canopy cover, and nutrient concentrations in the eroded sediments were measured for four years after the fire. Total precipitation was below average during the four-year study period, and most erosion occurred during short duration, moderate intensity summer rainfall events. The overall first year mean erosion rate was 16 Mg ha− 1 yr− 1, and this decreased significantly in the second year to 0.66 Mg ha− 1 yr− 1. There were no significant differences in erosion rates between treatments. In the first year, the seeded winter wheat provided 4.5% canopy cover, about a fourth of the total canopy cover, on the seeded plots; however, the total canopy cover on the seeded plots did not differ from the unseeded plots. The below average precipitation in the spring after seeding may have affected the winter wheat survival rate. In the fourth year of the study, the mean canopy cover in the fertilization treatment plots was 74%, and this was greater than the 55% mean canopy cover in the unfertilized plots (p = 0.04); however, there was no accompanying reduction in erosion rate for either the seeding or fertilization treatments. Revegetation by naturally occurring species was apparently not impacted by seeding during the four years of this study. The pH of the sediment as well as the concentrations of NO3–N, NH4–N, and K was not affected by seeding or fertilizing. The nutrient loads in the eroded sediment were minimal, with most of the nutrient loss occurring in the first postfire year. These results confirm that seeding success is highly dependent on rainfall intensity, amounts, and timing, and that soil nutrients lost in eroded sediments are unlikely to impair the site productivity. 相似文献
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试验选用泌乳后期,年龄、胎次、泌乳量、体况标准和采食量相近的50头健康荷斯坦奶牛作为试验动物。将奶牛随机分为5组(n=10):组间体重、产奶量、体况评分、麦草采食量差异不显著(P〉0.05)。结果显示:用甜味剂和绿色剂处理的两组.麦草采食量比对照组分别提高11.38%,7.08%,差异显著(P〈0.05)。草香组和果味剂组麦草平均采食量与对照组比没有提高,差异不显著(P〉0.05)。甜味剂组、草香剂组、对照组、绿色剂组和果味剂组产奶量分别降低了21.30%,19.24%,26.80%,17.60%,26.71%。甜味剂组、草香剂组和绿色剂组对试验奶牛的产奶量的降低相对对照组有一定的缓冲作用,但差异不显著(P〉0.05)。第1天,第15天,第30天采样检测乳脂率,各组间差异不显著(P〉0.05),甜味剂组,草香剂组和果味剂组第30天采样乳脂率相对第1天的乳脂率都有上升的趋势,分别上升16.72%,11.70%,9.68%。每次采样各组间乳蛋白检测结果差异不显著(P〉0.05),第30天的相对第1天的乳蛋白分别下降了12.46%,12.46%,11.88%,12.85%,3.19%。甜味剂处理和绿色剂处理对奶牛的体重和体况作用效果都有较好改善趋势,但各组间体重和体况评分差异都不显著(P〉0.05)。 相似文献
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hdlf@sohu.com 《勤云标准版测试》2006,(5)
在家兔饲料中添加紫花苜蓿、白三叶、聚合草、多年生黑麦草等四种优良多年生牧草能够增加家兔食欲,提高饲料转化率,促进家兔的生长。其中黑麦草饲喂效果最好,其次为聚合草。牧草混合饲喂的效果好于单独饲喂,其中黑麦草与白三叶混合饲喂效果最好。 相似文献