Equine and Livestock Nutrition Services (ELNS) , Pantfallen Fach, Tregaron, Ceredigion, Wales, SY256NG, United Kingdom.
MARS Horse Care UK Ltd, Old Wolverton Road, Old Wolverton, Buckinghamshire, MK12 5PZ, United Kingdom.
J Equine Vet Sci. 2023 Dec;131:104957. doi: 10.1016/j.jevs.2023.104957. Epub 2023 Oct 27.
The digestibility and nutritive values of pastures that were either freely or strip-grazed for 28 days were compared. Twelve ponies were individually grazed in adjacent, 10 m wide, rectangular paddocks. On day -1, each paddock length was adjusted to contain a 28-day supply of herbage DM at 1.5 % of pony BW/d. Ponies, (4/treatment) either accessed the entire 28-day supply from day 1 (TA), or gradually via strip-grazing treatments, SG1 and SG2. SG1 had a 'lead' fence spanning the paddock width that from day 3 was moved forward 1/26th of the paddock length daily, whereas SG2 had an additional 'back fence', that was advanced the same distance as the lead fence daily. Pasture nutrient contents and estimated nutrient digestibilities (eD) were determined weekly. From weeks 1-4, mean strip-grazed pasture contents (% DM) of water-soluble carbohydrate (WSC) and crude protein declined from 15.7-10.2 and 9.4-8.7, respectively, whereas neutral- and acid-detergent fibre increased from 53.6-60.5 and 35.2-38.0, respectively. Corresponding values for TA pastures were 17.7-5.2, 8.9-8.7, 54.6-69.2 and 35.7-43.6. Concomitantly, calculated digestible energy (cDE) (MJ/kg DM) of strip-grazed and TA pastures declined from 9.7-8.9 and 9.6-7.8, respectively and eDMD of all treatments declined (P<0.05). By week 4, TA pasture WSC, cDE and eDMD were lower and fibre contents higher (P<0.05) than the strip-grazed pastures. TA animal cDE intakes in weeks 1 and 2 exceeded requirements by 42 % vs. 8 % by strip-grazed animals. Strip-grazing delivered a steadier nutrient supply than TA, potentially conferring health benefits to animals prone to metabolic dysfunction.
我们比较了自由放牧和划区轮牧 28 天后牧草的消化率和营养价值。12 匹小马被单独放牧在相邻的 10 米宽的长方形围场中。在第-1 天，每个围场的长度都调整为包含 28 天的牧草 DM 供应量，为小马体重的 1.5%。小马（4/处理）要么从第 1 天开始就可以获得整个 28 天的供应量（TA），要么通过划区轮牧处理（SG1 和 SG2）逐渐获得。SG1 在围场宽度上有一个“引导”围栏，从第 3 天开始，每天向前移动 1/26 围场长度，而 SG2 则有一个额外的“后围栏”，每天也向前移动相同的距离。每周测定牧草养分含量和估计养分消化率（eD）。从第 1-4 周，划区轮牧牧草的水溶性碳水化合物（WSC）和粗蛋白含量（% DM）从 15.7-10.2 和 9.4-8.7 逐渐下降，而中性和酸性洗涤剂纤维则从 53.6-60.5 和 35.2-38.0 逐渐增加。TA 牧场的相应值为 17.7-5.2、8.9-8.7、54.6-69.2 和 35.7-43.6。与此同时，划区轮牧和 TA 牧场的可消化能（cDE）（MJ/kg DM）分别从 9.7-8.9 和 9.6-7.8 逐渐下降，所有处理的 eDMD 都下降（P<0.05）。到第 4 周，TA 牧场的 WSC、cDE 和 eDMD 低于划区轮牧牧场，而纤维含量较高（P<0.05）。第 1 和第 2 周 TA 牧场动物的 cDE 摄入量比划区轮牧动物分别高出 42%和 8%。与 TA 相比，划区轮牧提供了更稳定的养分供应，可能会给易发生代谢功能障碍的动物带来健康益处。
