Amanlou H, Maheri-Sis N, Bassiri S, Mirza-Aghazadeh A, Salamatdust R, Moosavi A, Karimi V
Department of Animal Science, Faculty of Agriculture, Zanjan University, P.O.Box 45195-313, Zanjan, Iran.
Department of Animal Science, Shabestar Branch, Islamic Azad University, Shabestar, East Azerbaijan, Iran.
Open Vet J. 2012;2(1):88-94. Epub 2012 Sep 26.
Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight) were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (P<0.05) high NEL intakes when compared to control with no fat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; P<0.01) and FCM production (1.05-2.79; P<0.01). Milk fat yield and percentage of cows fed fat-supplemented diets were significantly (P<0.01 and P<0.05 respectively) higher than control. Between fat-supplemented diets, roasted soybean caused highest milk fat yield and extruded soybean caused lowest milk fat yield. There was no significant effect of supplemental fat on the milk protein and lactose content and yield. Feed efficiency of fat-supplemented diets was significantly (P<0.01) higher than control. Body weight, body weight change and BCS (body condition score) of cows, as well as energy balance and energy efficiency were similar between treatments. In conclusion, while there was no significant effect of fat sources on production response of cows, fat originating from heat-treated soybean help to minimize imported RUP (rumen undegradable protein) sources level as fish meal in comparison with tallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans.
选用30头经产荷斯坦奶牛（产奶29.8±4.01天；体重671.6±31.47千克），采用完全随机设计，比较牛油、生大豆、膨化大豆和烤大豆这四种脂肪来源的营养价值，试验为期8周。试验日粮一种是对照日粮，含27.4%苜蓿青贮、22.5%玉米青贮和50.1%精料，另外四种日粮分别添加牛油、生大豆、膨化大豆或烤大豆，使补充脂肪含量达到1.93%。各处理间干物质和净能摄入量相似，但与不添加脂肪的对照相比，饲喂含脂肪日粮的奶牛净能摄入量显著更高（P<0.05）。补充脂肪，无论是牛油还是全脂大豆，均提高了产奶量（1.89 - 2.45千克/天；P<0.01）和乳脂校正乳产量（1.05 - 2.79；P<0.01）。饲喂补充脂肪日粮的奶牛乳脂肪产量和乳脂肪率显著高于对照（分别为P<0.01和P<0.05）。在补充脂肪的日粮之间，烤大豆使乳脂肪产量最高，膨化大豆使乳脂肪产量最低。补充脂肪对乳蛋白和乳糖含量及产量无显著影响。补充脂肪日粮的饲料效率显著高于对照（P<0.01）。各处理间奶牛的体重、体重变化和体况评分，以及能量平衡和能量效率相似。总之，虽然脂肪来源对奶牛生产反应无显著影响，但与牛油和生大豆油相比，热处理大豆来源的脂肪有助于将瘤胃不可降解蛋白来源水平（如鱼粉）降至最低。在本研究中，膨化大豆油和烤大豆油的营养价值之间无统计学差异。
