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11.
不同精料添加量对绵羊饲料瘤胃降解的影响   总被引:6,自引:0,他引:6  
6只8月龄小尾寒羊公羊(平均体重为29.98kg),安装永久性瘤胃瘘管。采用对比试验设计,分150g/d、250g/d、350g/d、450g/d四个混合精粒水平,玉米秸自由采食。采用铬标记法测定饲料瘤胃流通量,采用尼龙袋法测定饲料瘤胃降解率。试验结果表明:玉米秸、玉米面、麸皮和棉仁粕的营养物质瘤胃有效降解率与精料水平之间以及饲料瘤胃流通速度(k)与精料水平之间均存在二次函数关系。饲料k值均在日喂250g精料时最大,之后又随精料水平的提高而下降,所测饲料营养成分瘤胃有效降解率在350-450g精粒水平之间最高,个别饲料营养成分瘤胃有效降解率在250-350g精料水平之间达最大值,因此,为提高秸秆利用率及日粮的合理利用,以精粒添加量不大于350g为宜。  相似文献   
12.

Sheep feeding regimes were studied in years when little roughage was available by comparing two levels of concentrate (high and low) and three types of roughage [silage, hay and ammonia-treated (AT) straw]. The duration of the experiment was two production years (1995 and 1996) and included 121 ewes. The traits recorded were live weight for ewes, ewe performance (number of lambs, birth weight, average daily weight gain) and slaughter data (class, value and weight). After 14 weeks, ewes fed low-concentrate AT straw were 6-12 kg lighter ( P < 0.01) than the other ewes, and tended to be undernourished. Lambs from these ewes were up to 1.5 kg lighter at birth ( P <0.01) than the other lambs. No difference was found at the end of the experiment. The gross margin in the group fed the high-concentrate AT straw diet was 205 NOK higher ( P <0.01) than the group with the lowest gross margin (low-concentrate hay). Wool and wood eating was found in groups fed large amounts of concentrate and silage.  相似文献   
13.
本试验选择16头处于干奶期的健康荷斯坦奶牛,各试验牛体重、年龄、胎次相近,随机分成4组,每组4头。试验分为两期,一期饲喂基础日粮,二期以苜蓿、羊草、全株玉米青贮和干玉米秸秆各粗饲料替代30%基础日粮。考察不同粗饲料对奶牛能量代谢的影响。试验结果表明苜蓿的饲草相对饲用价值(RFV)值最高,一定程度上说明了苜蓿的营养价值最高,玉米青贮较玉米秸秆饲草相对饲用价值(RFV)值高,说明青贮改善了玉米秸秆的品质,提高其营养价值。  相似文献   
14.
为研究不同粗饲料日粮对奶牛产奶量、乳成分和经济效益的影响,选取体重、年龄、胎次、泌乳日龄相近的荷斯坦奶牛25头,分别饲喂玉米(Zea mays)秸秆(100%)、玉米秸秆(70%)+苜蓿(Medicago sativa)干草(30%)、羊草(Leymus chinensis)(70%)+苜蓿干草(30%)、全株玉米青贮(70%)+苜蓿干草(30%)和全株玉米青贮(50%)+羊草(30%)+苜蓿干草(20%),精粗比50∶50。结果表明:与粗饲料单纯饲喂玉米秸秆相比,全株玉米青贮+苜蓿干草组可提高产奶量26.52%,提高乳脂率6.03%,增收3.87元·头-1·d-1;其次为全株玉米青贮+羊草+苜蓿干草组,可提高产奶量21.20%,提高乳脂率4.6%,增收2.83元·头-1·d-1;再次为玉米秸秆+苜蓿干草组可提高产奶量10.05%,提高乳脂率2.59%,增收2.46元·头-1·d-1;羊草+苜蓿干草组可提高产奶量11.85%,提高乳脂率2.01%,增收不明显。表明全株玉米青贮+苜蓿干草组饲喂效果最好。  相似文献   
15.
粗饲料的营养价值较低。通过适宜的日粮营养补添调控反刍动物瘤胃微生物区系的生长可提高粗饲料的利用效率。日粮营养补添包括 :改善日粮精粗比以增加能量供给 ;供给瘤胃氨态氮 ;补添蛋白 ;补添矿物元素 ;以及应用酸碱或缓冲盐。  相似文献   
16.
Livestock production and ruminants in particular are an integral part of the organic mixed farming concept. In this paper, the feeding patterns of 26 organic dairy farms in two different regions in Germany are analysed, with particular emphasis on the amount and proportion of concentrates and purchased feed related to the dairy performance expressed per cow and hectare. Calculated on an energy basis (MJ NEL), the annual average milk yield of 6737 kg cow− 1 is derived from roughage (74%), concentrates and cobs (23%), and commercial processing by-products (e.g., spent grains) (3%). Per cow and year, 937 kg dry matter (DM) (range: 0–2724 kg) of concentrates are fed with an intensity of 135 g kg− 1 milk (range: 0–378 g kg− 1). Approximately 65% of the concentrates and commercial processing by-products are purchased. The area-related milk yield is almost 7000 kg ha− 1. For fodder production, 0.96 ha per cow is needed, of which 0.85 ha is farm land. The equivalent production area for purchased fodder is 0.11 ha. In the analysed region in northwestern Germany, most correlations between milk yield and analysed feeding parameters are close and significant. This is in contrast to the region in the south, where the variability of amount and proportion of the different feed types is predominantly independent of the milk yield. Intensification of dairy production to increase milk performance using a higher proportion of concentrates and purchased feed at some of the analysed farms needs to be carefully assessed according to the organic farming profile.  相似文献   
17.
The rapid intake of high-cereal, low-roughage meals may cause gastrointestinal and behavioral disorders. We investigated some of the factors that can affect the rate of intake (ROI) in four separate studies. Study 1 investigated the effect of chaff length and addition rate on the ROI of oats. The ROI decreased as more chaff was added to the diet, attaining significance (P < .05, n = 6) at levels above 15% addition and reaching a plateau at ∼50%. This was independent of stalk length (1.4 cm vs. 4.1 cm). Study 2 showed that meal size (varying from 0.5 to 4 g/kg BW) did not affect the ROI for a cereal-based meal, nor was ROI altered by the addition of 10% molasses (n = 6). Study 3 demonstrated that ROI changed markedly over the course of a meal, commencing at an average rate of 74 g/minute for the first 5 minutes and decreasing to 15.8 g/minute after 30 minutes (n = 6). Study 4 examined the effects of breed, BW, exercise, and gender in 71 horses. In Clydesdales, BW affected ROI (P < .05), and Clydesdales had a faster ROI than Thoroughbreds of similar BW (81.8 ± 6.8 vs. 66.0 ± 3.35 g/minute; P < .05). Exercise level, age, and gender did not impact ROI significantly. The results highlight the effectiveness of feeding chaff to slow ROI and demonstrate the need for a standardized protocol if ROI is to be compared between different studies.  相似文献   
18.
我国南方地区农作物副产品资源十分丰富,是草食动物重要的粗饲料来源,但目前并未得到合理利用。对几种农副产品在南方地区的主要产量分布、营养成分构成以及国内外一些粗饲料加工方法进行综述。  相似文献   
19.
潘利  张玉娟  阎子盟  唐士明  黄顶 《安徽农业科学》2014,(17):5485-5486,5492
河北坝上地区是我国华北农牧交错区的主体部分,草原畜牧业是该区域的主导产业,针对该区域草地畜牧业所面临的生态和生产的问题,选取沽源、围场和丰宁3个典型县域草地为研究对象,采用野外调查测定和年鉴统计数据相结合的方法,从饲草供给与家畜需求的角度进行了比较分析。结果表明,3个县的草地产量与2012年农业部年鉴统计数据相一致,围场最高,其次是沽源,丰宁最低;饲草供给量与年鉴统计结果一致,且沽源县有机质、全氮、全磷含量在4个土层均显著高于丰宁和围场县,并根据各个县农业资源现状提出了沽源和丰宁2个县构建“粮-经-饲”三元种植结构模式、建立人工草地、开发新的饲料资源等方法解决饲草需求不足问题。  相似文献   
20.
本文综述了牛奶中乳脂的产生机制、影响牛奶乳脂率的因素以及提高牛奶乳脂率的措施,以期为奶牛场提高乳脂率提供参考.  相似文献   
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