Teagasc, Animal & Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland P61 C996; Animal Production Systems group, Department of Animal Sciences, Wageningen University and Research, Wageningen, the Netherlands 6700 AH.
Animal Production Systems group, Department of Animal Sciences, Wageningen University and Research, Wageningen, the Netherlands 6700 AH.
J Dairy Sci. 2023 Sep;106(9):6427-6443. doi: 10.3168/jds.2022-22659. Epub 2023 Jul 26.
The objective of this study was to identify potential effects of increased grazing intensity, characterized by differing pasture availability and stocking rate, on indicators of welfare during both early and late grazing periods. Seventy spring-calving, pasture-based Holstein-Friesian and cross-bred dairy cows, averaging 35 ± 16 d in milk on the first day of data collection, were assigned to 3 treatments (20-26 cows/treatment) representing a range in grazing intensity: LO (high pasture availability, 980 kg DM/ha opening cover, 2.75 cows/ha, 90:10% pasture:concentrate diet), MOD (medium pasture availability, 720 kg DM/ha opening cover, 2.75 cows/ha, 90:10% pasture:concentrate diet), and HI (low pasture availability, 570 kg DM/ha opening cover, 3.25 cows/ha, 80:20% pasture:concentrate diet); representative of current, best practice and proposed production levels respectively for this system. Welfare indicators were locomotion score, digital dermatitis and white line disease, rumen fill, ocular and nasal discharge, integument damage to the neck-back and hock regions, and lying time. Data were collected during a 5-wk early grazing period in spring (EG) and a 7-wk late grazing period in autumn (LG). Average daily lying time was recorded for 8 to 10 focal cows per treatment. Results demonstrated only minor treatment effects. Cows on MOD [odds ratio (OR) = 3.11] and HI (OR = 1.95) were more likely to display nasal discharge compared with LO. Cows on MOD tended to have more damage to the skin on the neck-back region than LO (OR = 4.26). Total locomotion score (maximum = 25) was greater on LOW (7.1 ± 0.20) compared with HI (6.5 ± 0.19). Average lame cow prevalence for EG and LG respectively was 15.3 ± 3.12% and 39.2 ± 3.00% (LO), 20.0 ± 2.58% and 24.2 ± 5.69% (MOD), and 14.9 ± 4.79% and 17.0 ± 3.44% (HI). Cows on HI were less likely to have impaired walking speed than either LO (OR = 0.24) or MOD (OR = 0.29). Cows on both HI (OR = 0.36) and MOD (OR = 0.40) were less likely to display impaired abduction or adduction compared with those on LO. An interaction between treatment and period revealed longer lying times for cows on LO (10.6 h/d ± 0.39) compared with both MOD and HI (8.7 ± 0.43 and 8.4 ± 0.41 h/d) during EG only. The greatest effects were across grazing periods, with all indicators except rumen fill and locomotion score demonstrating improvements from EG to LG. This suggests cows were able to cope well with increasing levels of grazing intensity, and that regardless of treatment, a greater number of days on pasture led to improvements in welfare indicators.
本研究的目的是确定增加放牧强度的潜在影响，其特征为不同的牧场可用性和放牧率，以确定早期和晚期放牧期间福利的指示物。70 头春季产犊、基于牧场的荷斯坦弗里森和杂交奶牛，在数据收集的第一天平均有 35±16 天的产奶量，被分配到 3 个处理组（每组 20-26 头牛），代表不同的放牧强度：低（高牧场可用性，980 公斤 DM/公顷开放覆盖，2.75 头/公顷，90:10%牧场：浓缩饲料）、中（中牧场可用性，720 公斤 DM/公顷开放覆盖，2.75 头/公顷，90:10%牧场：浓缩饲料）和高（低牧场可用性，570 公斤 DM/公顷开放覆盖，3.25 头/公顷，80:20%牧场：浓缩饲料）；分别代表该系统当前、最佳实践和拟议的生产水平。福利指标包括运动评分、皮肤病变（如：趾间皮炎、白线病）、瘤胃充盈度、眼部和鼻部分泌物、颈部和跗关节区域的皮肤损伤以及卧息时间。数据是在春季的 5 周早期放牧期（EG）和秋季的 7 周晚期放牧期（LG）收集的。每个处理组记录了 8 到 10 头有代表性的奶牛的平均卧息时间。结果仅显示出轻微的处理效应。与低（OR=3.11）和高（OR=1.95）相比，MOD 上的奶牛更有可能出现鼻部分泌物。MOD 上的奶牛颈部和跗关节区域的皮肤损伤比低（OR=4.26）更有可能出现。总运动评分（最高=25）在低（7.1±0.20）上高于高（6.5±0.19）。EG 和 LG 中跛行奶牛的平均患病率分别为 15.3±3.12%（低）、20.0±2.58%（MOD）和 14.9±4.79%（HI），39.2±3.00%（低）、24.2±5.69%（MOD）和 17.0±3.44%（HI）。与低相比，高放牧的奶牛不太可能出现行走速度受损（OR=0.24）或 MOD（OR=0.29）。与低相比，HI（OR=0.36）和 MOD（OR=0.40）上的奶牛不太可能表现出运动受限或过度运动。处理和周期之间的相互作用表明，与 MOD 和 HI 相比，LO 上的奶牛在 EG 期间的卧息时间更长（10.6 小时/天±0.39）。只有在 EG 期间，所有指标（除瘤胃充盈度和运动评分外）均优于 LG。这表明奶牛能够很好地应对放牧强度的增加，并且无论处理方式如何，在牧场上的天数增加都导致了福利指标的改善。
