Castro Jaime Citlali Anais, Crosby Galvan María Magdalena, Burgueño Ferreira Juan Andrés, Ramírez Valverde Rodolfo, Jiménez Rosales Juan Daniel, Améndola Massiotti Ricardo Daniel
Universidad Autonoma Chapingo, Programa de Posgrado en Producción Animal, Texcoco, Mexico.
Colegio de Postgraduados Campus Montecillo, Programa de Ganaderia, Texcoco, Mexico.
Trop Anim Health Prod. 2025 Mar 4;57(2):94. doi: 10.1007/s11250-025-04354-2.
The objective was to evaluate the response of New Zealand Holstein cows to concentrate supplementation at contrasting times of the day on herbage intake and ingestive behavior. Two experiments were conducted in winter and spring-summer in a grazing dairy production system of Medicago sativa L. with Dactylis glomerata L. pastures. Three moments of supplying 5.0 kg DM concentrate cow d were used: AM after morning milking, PM after afternoon milking, and the AM-PM control equally dividing that amount after both milkings. The experimental units were groups of six cows in winter (a total of 18 cows) and five cows in spring-summer (a total of 15 cows), additionally their respective grazed areas were also considered as experimental units. The design used was a three × three (treatments × periods) cross-over; the allotment of groups to the treatments was consecutive and randomized. The management criterion of rotational grazing was 8 cm of residual forage height for all treatments. Each time the target height of residual herbage was reached, the portable electric fence was manually moved forward allowing on average 36 m fresh pasture. In winter, intake was not different (P < 0.5) between treatments; however, during spring-summer it was 8% lower (P < 0.005) with AM supplementation. There was no effect (P > 0.5) of treatments on total grazing time, rumination and other activities. In conclusion, AM supplementation in spring-summer resulted in dominant evening grazing, and herbage was utilized at its time of highest nutrient concentration.
目的是评估新西兰荷斯坦奶牛在一天中不同时间补充精饲料对其牧草摄入量和采食行为的影响。在一个以紫花苜蓿和鸭茅为牧场的放牧式奶牛生产系统中，于冬季和春夏季进行了两项试验。采用了三种给每头奶牛每天供应5.0千克干物质精饲料的时间点：上午挤奶后（AM）、下午挤奶后（PM）以及在两次挤奶后将该量平均分配的上午-下午对照（AM-PM）。试验单元在冬季为每组6头奶牛（共18头奶牛），在春夏季为每组5头奶牛（共15头奶牛），此外，它们各自的放牧区域也被视为试验单元。所采用的设计是三×三（处理×时期）交叉设计；各处理组的分配是连续且随机的。所有处理的轮牧管理标准是剩余牧草高度为8厘米。每次达到目标剩余牧草高度时，手动移动便携式电围栏，平均留出36米的新鲜牧场。在冬季，各处理间的摄入量没有差异（P＞0.5）；然而，在春夏季，上午补充精饲料时摄入量降低了8%（P＜0.005）。各处理对总放牧时间、反刍和其他活动没有影响（P＞0.5）。总之，在春夏季上午补充精饲料导致傍晚放牧占主导，并且牧草在其营养浓度最高的时候被利用。
