共查询到20条相似文献,搜索用时 156 毫秒
1.
2.
3.
粗、精料干物质比例的变化对奶牛日粮成本的影响 总被引:1,自引:0,他引:1
就特定的泌乳奶牛营养需要量,设计了7种不同饲粮粗料与精料比例(F:C=82:18、70:30、65:35、60:40、55:45、50:50和40:60)的日粮配方,研究饲粮粗料与精料比例对奶牛日粮成本的影响规律。结果表明,日粮中精料用量不是越少越好,随着日粮中精料用量在一定范围内的增加,在大多数情况下,往往会降低日粮成本,但必须是以日粮原料中具有可以替代的廉价原料为基础。只有在综合考虑日粮成本、精料补充料的可加工性,以及粗料饲喂的可执行性等决定最合理的粗料与精料比例。 相似文献
4.
我国粗饲料资源丰富,粗饲料在奶牛生产中的应用也日益增加。本文从粗饲料长度和精粗比两方面综述了日粮中不同粗饲料对奶牛生产的影响,为粗饲料在奶牛养殖业的合理利用提供理论依据。 相似文献
5.
日粮不同精粗比例对中产奶牛生产性能的影响 总被引:2,自引:2,他引:0
本课题应用随机分组试验设计,将40头中等产奶量的荷斯坦奶牛随机分为4组,Ⅰ组为对照组,Ⅱ、Ⅲ和Ⅳ组为试验组,日粮精、粗比例依次为50%:50%、40%:60%、35%:65%和30%:70%,研究不同精、粗比例对奶牛TMR日粮采食量、产奶量、乳脂率以及其他乳成分的影响。结果表明,随着粗饲料比例的增加,试验各组采食量和粗饲料采食量都显著(P〈0.05)高于对照组,产奶量也显著(P〈0.05)高于对照组,并且日产奶量(Y,kg)与日采食量(X,kg)之间存在着显著(P〈0.05)的线性相关关系:y=0.66x-17.73,(r^2=0.76);试验组乳脂率显著高于对照组,其中试验Ⅲ组和Ⅳ组与对照组相比,差异极显著(P〈0.01),并且乳脂率(Y,%)与粗饲料采食量(X,kg)之间存在显著(P〈0.05)的线性相关关系:y=0.046x+1.78,r^2=0.56;试验组其他乳成分含量与对照组均差异不显著(P〉0.05)。统计分析表明,试验Ⅱ组的4%校正乳产量最高,日粮采食量与校正乳产量比值最低,即综合经济效益最好。 相似文献
6.
高品质的粗饲料可以提高奶牛的生产性能,合理的日粮精粗比更对奶牛生产有着重要的作用。研究表明,日粮中的精粗比过低,会降低奶牛采食量,导致奶牛养分摄入不足,产奶量和乳脂率降低。日粮中的精粗比过高则会破坏瘤胃内环境稳定导致瘤胃pH值降低,影响微生物蛋白、氨态氮和VFA的合成,严重导致瘤胃酸中毒,致使奶牛淘汰或死亡,降低生产效益。综合分析,探寻高品质粗饲料以及最佳的日粮精粗比是奶业发展的重中之重。本综述主要叙述粗饲料的品种与长度以及奶牛日粮中粗饲料添加水平对奶牛的健康以及生产性能的影响。 相似文献
7.
不同精粗比例TMR日粮对中产奶牛氮代谢的影响 总被引:1,自引:0,他引:1
应用随机分组试验设计,将40头荷斯坦奶牛随机分为4组.Ⅰ组为对照组,Ⅱ、Ⅲ和Ⅳ组为试验组,TMR日粮精粗比例依次为50%:50%,40%:60%,35%:65%,30%:70%.研究不同精粗比例对奶牛蛋白质消化代谢的影响.结果表明:随日粮粗饲料比例增加,各组总氮采食量、粪氮、尿氮均差异不显著(P>0.05);试验Ⅱ组奶氮显著高于试验Ⅲ组和Ⅳ组(P<0.05);氮表观消化率总体呈增加趋势,其中试验Ⅱ组显著高于Ⅰ组(P<0.05);试验Ⅱ组氮表现代谢率最高,相关分析得出:氮表现代谢率(y,%)与血清尿素氮(x,mmol/L)呈极显著负相关(P<0.01):y=-5.28x+66.55,r2=0.65;氮转化率呈增加趋势,分析得出粗饲料采食量(x,kg/d)与氮转化效率(y,%)呈显著二次曲线相关(P<0.05):y=-0.063x2+1.76x+2.42,r2=0.62;氮沉积量呈增加趋势,其中试验Ⅱ组最高,当计入再循环尿素氮后,氮沉积量(y,kg/d)与氮采食量(x,kg/d)之间存在显著的线性相关(P<0.05):y=0.4x-0.06,r2=0.41.因此通过对比分析可知,TMR日粮精粗比例为40%:60%(试验Ⅱ组)最有利于蛋白质的消化代谢和利用. 相似文献
8.
9.
美国威克鲁农牧研究所的研究表明:对于不同泌乳期的奶牛应分别按精粗饲料的比例搭配,才能取得最好的产奶水平和饲料转化效益比,其具体的比例是:对产奶期20~120天,日产奶量高于20kg的奶牛,精饲料占日粮的40~50%;产奶期121~210天,日产奶量15~20公斤的奶牛,精饲料应占30~35%;产奶期211~305天,日产奶量15公斤以下的,精饲料占20~25%。实践证明,这样可获得最好的饲料效益比。 相似文献
10.
11.
12.
13.
日粮精粗比对奶牛瘤胃内环境的影响 总被引:3,自引:0,他引:3
本文主要讨论了日粮精粗比对奶牛瘤胃内环境的影响,包括对瘤胃细菌菌群数量、瘤胃pH值、瘤胃内容物稀释率和外流速度、氨态氮浓度以及挥发性脂肪酸的影响。 相似文献
14.
A. Huuskonen P. Lamminen E. Joki-Tokola 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):220-229
Abstract The objectives of the study with growing dairy heifers were to determine the effects on animal performance of (1) concentrate level and (2) the concentrate composition in the grass silage-based diet. Animals (30 heifers) were randomly assigned to three feeding treatments: (1) low level (1.75 kg dry matter (DM)/d) of rolled barley (LB); (2) low level (1.75 kg DM/d) of commercial pelleted concentrate (LC); and (3) medium level (3.5 kg DM/d) of commercial pelleted concentrate (MC). All animals were also offered grass silage and hay. The commercial concentrate contained more crude protein than barley grain (135 g/kg DM vs. 205 g/kg DM). The data were analysed using analysis of variance and differences between the treatments were tested by orthogonal contrasts: LC vs. MC and LB vs. LC. The growth of the heifers increased and carcass conformation improved with increasing concentrate level. Commercial concentrate did not improve animal performance compared with barley grain. 相似文献
15.
16.
The effect of summer grazing in large Danish dairy herds and certain management characteristics of grazing were studied for their impact on dairy cow mortality. Mortality data (from the Danish Cattle Database) from 391 Danish dairy herds (>100 cows) were combined with information from a questionnaire survey of grazing procedures on these herds in 2008. In all, 131 of the herds were identified as summer grazing and 260 as zero-grazing herds. The mortality was affected by an interaction of summer grazing and milking system. The risk of a cow dying was reduced to 46% in a grazing compared to a zero-grazing herd having automatic milking system. In traditional milking system, mortality was reduced to 75% in grazing compared to zero-grazing herds. Within the grazing herds, the risk of mortality decreased with increasing number of hours on pasture during the season. Free access between barn and pasture was associated with increased cow mortality. 相似文献
17.
Relationships between dairy cow mastitis and fertility management and farm performance 总被引:1,自引:0,他引:1
C. W. Rougoor W. J. A. Hanekamp A. A. Dijkhuizen M. Nielen J. B. M. Wilmink 《Preventive veterinary medicine》1999,39(4):463-264
A field study was carried out on 38 dairy farms in the Netherlands to determine the relationship between mastitis and fertility management with 305-day milk production and gross margin. Questionnaires were used to get insight into the farmers' management. Out of 150 variables related to mastitis and fertility management, and technical and economic results, 44 variables were selected based on correlation of ≥0.25 or ≤−0.25 with milk production and/or gross margin. These variables were used in two separate partial least-squares (PLS) analyses. PLS has the advantage that it can handle a large number of variables in relation to the number of cases. The PLS-model of 305-day milk production had R2 = 0.54 and showed a positive relation between 305-day milk production and awareness of the farmer regarding bulk somatic-cell count (BSCC), the goal level of the farmer for BSCC, and hygiene of the milking parlour. Fertility was negatively related to 305-day milk production, in spite of a relatively good fertility management on high-producing farms. R2 = 0.46 for gross margin. The aspiration level of fertility did not seem to affect gross margin, but awareness of BSCC and calving interval (CI) had positive effects. Such awareness seemed a general parameter for good economic results, because it was correlated with different aspects of gross margin. 相似文献
18.
19.
20.
奶牛乳房炎发病率高,每年给奶业生产造成严重的经济损失,其主要病因是致病菌对机体的感染。本文试图从奶牛自身性状、营养、环境、管理4个方面分析可能导致致病菌对机体感染的原因,以期为乳房炎的防治提供参考。 相似文献