Manthey A K, Anderson J L
Dairy and Food Science Department, South Dakota State University, Brookings 57007.
Dairy and Food Science Department, South Dakota State University, Brookings 57007.
J Dairy Sci. 2017 May;100(5):3713-3717. doi: 10.3168/jds.2016-12041. Epub 2017 Mar 2.
The objective of this study was to determine the effect of increasing the inclusion rate of distillers dried grains with solubles (DDGS) in replacement of forage in diets that were limit-fed during peripubertal growth on performance during the first 3 mo of first lactation. A secondary objective was to also characterize reproductive performance of the dairy heifers. A 16-wk randomized complete block design study was conducted using 48 Holstein heifers (199 ± 2 d of age) with 3 treatments. Treatments were (1) 30% DDGS, (2) 40% DDGS, and (3) 50% DDGS, with the remainder of the diet consisting of grass hay and 1.5% mineral mix. Heifers were individually limit-fed using Calan gates at 2.65, 2.50, and 2.35% of body weight on a dry matter basis for 30, 40, and 50% DDGS, respectively. After completing the feeding study, heifers were fed a common diet according to standard herd management. Data on reproductive performance and milk production for the first 3 mo of lactation were collected for each heifer from dairy herd records. At 3 wk prepartum and at calving, body weight, frame measurements, and body condition score were recorded. We found no differences in reproductive or frame measurements taken around parturition. However, due to relatively small numbers of heifers for evaluation of reproductive parameters, results should be viewed as qualitative rather than conclusive, and more research is necessary. We noted a treatment by month effect for somatic cell count; however, there were no other differences for any of the lactation parameters measured. Results demonstrate that up to 50% of diet can be fed in limit-fed rations as DDGS, compared with 30 or 40%, to peripubertal dairy heifers without negative consequences to first-lactation performance during the first 3 mo.
本研究的目的是确定在围青春期生长期间限制饲喂的日粮中，提高玉米干酒糟及其可溶物（DDGS）替代草料的比例，对首次产犊后前3个月产奶性能的影响。第二个目的是描述奶牛小母牛的繁殖性能。采用16周随机完全区组设计研究，对48头荷斯坦小母牛（199±2日龄）进行3种处理。处理方式为：（1）30% DDGS，（2）40% DDGS，（3）50% DDGS，日粮的其余部分由禾本科干草和1.5%矿物质预混料组成。分别以干物质计，按体重的2.65%、2.50%和2.35%，使用卡兰门对小母牛进行个体限饲，分别对应30%、40%和50% DDGS的日粮。完成饲喂研究后，根据标准牛群管理方式给小母牛饲喂常规日粮。从奶牛群记录中收集每头小母牛产犊后前3个月的繁殖性能和产奶量数据。在产前3周和产犊时，记录体重、体尺和体况评分。我们发现分娩前后的繁殖性能或体尺测量没有差异。然而，由于用于评估繁殖参数的小母牛数量相对较少，结果应视为定性而非结论性的，需要更多研究。我们注意到体细胞计数存在处理×月份效应；然而，所测量的任何泌乳参数均无其他差异。结果表明，与30%或40%相比，围青春期奶牛小母牛在限饲日粮中可饲喂高达50%的DDGS，且对首次产犊后前3个月的产奶性能没有负面影响。
