Department of Animal Sciences, School of Agriculture, Policy and Development, University of Reading, RG6 6EU, UK.
AHDB Dairy, Agriculture and Horticulture Development Board, Stoneleigh Park, Kenilworth, Warwickshire CV8 2TL, UK.
Animal. 2021 Jul;15(7):100248. doi: 10.1016/j.animal.2021.100248. Epub 2021 Jun 4.
Minimising phosphorus (P) feeding to dairy cows can reduce feed costs and minimise water pollution without impairing animal performance. This study aimed to determine current P feeding practices and identify the barriers to and motivators for minimising P feeding on dairy farms, using Great Britain (GB) dairy farming as an example of diverse systems. Farmers (n = 139) and feed advisers (n = 31) were involved simultaneously in independent questionnaire surveys on P feeding in dairy farms. Data on the herd size, milk yield and concentrate fed were analysed using ANOVA to investigate the effect of farm classification, region, and feed professional advice. Chi-square tests were used to investigate associations between farm characteristics and implemented P feeding and management practices. Most farmers (72%) did not know the P concentration in their lactating cow's diet and did not commonly adopt precision P feeding practices, indicating that cows might have been offered dietary P in excess of recommended P requirement. Farmers' tendency to feed P in excess of recommendations increased with herd size, but so did their awareness of P pollution issues and likeliness of testing manure P. However, 68% of farmers did not analyse manure P, indicating that mineral P fertiliser application rates were not adjusted accordingly, highlighting the risk of P being applied beyond crops' requirement. Almost all farmers (96%) were willing to lower dietary P concentration but the uncertainty of P availability in feed ingredients (30%) and concerns over reduced cow fertility (22%) were primary barriers. The willingness to reduce dietary P concentrations was driven by the prospect of reducing environmental damage (28%) and feed costs (27%) and advice from their feed professionals (25%). Most farmers (70%) relied on a feed professional, and these farmers had a higher tendency to analyse their forage P. However, farmers of pasture-based systems relied less on feed professionals. Both farmers (73%) and feed advisers (68%) were unsatisfied with the amount of training on P management available. Therefore, the training on P management needs to be more available and the influence that feed professionals have over P feeding should be better utilised. Study findings demonstrate the importance of considering type of dairy farming systems when developing precision P feeding strategies and highlight the increasing importance of feed professionals in minimising P feeding.
减少奶牛的磷（P）喂养量可以降低饲料成本，减少水污染，而不会影响动物的生产性能。本研究旨在以英国（GB）奶牛养殖为例，确定当前奶牛养殖场的 P 喂养实践，并确定减少 P 喂养的障碍和动机。同时，让农民（n=139）和饲料顾问（n=31）参与关于奶牛养殖场 P 喂养的独立问卷调查。使用方差分析（ANOVA）分析了牛群规模、牛奶产量和精饲料喂养的数据，以调查农场分类、地区和饲料专业建议的影响。使用卡方检验（chi-square tests）调查了农场特征与实施的 P 喂养和管理实践之间的关联。大多数农民（72%）不知道他们泌乳奶牛饮食中的 P 浓度，也没有普遍采用精确的 P 喂养实践，这表明奶牛可能摄入了超过推荐 P 需求的日粮 P。农民过量喂养 P 的倾向随着牛群规模的增加而增加，但他们对 P 污染问题的认识和测试粪便 P 的可能性也随之增加。然而，68%的农民没有分析粪便 P，这表明矿物 P 肥料的应用率没有相应调整，突出了 P 被施用到超出作物需求的风险。几乎所有的农民（96%）都愿意降低日粮 P 浓度，但饲料成分中 P 可用性的不确定性（30%）和对奶牛生育能力下降的担忧（22%）是主要障碍。降低日粮 P 浓度的意愿是由减少环境破坏（28%）和饲料成本（27%）以及饲料专业人员的建议（25%）驱动的。大多数农民（70%）依赖饲料专业人员，这些农民更倾向于分析他们的饲料 P。然而，以牧草为基础的系统的农民对饲料专业人员的依赖程度较低。农民（73%）和饲料顾问（68%）都对现有的 P 管理培训数量不满意。因此，需要提供更多的 P 管理培训，更好地利用饲料专业人员对 P 喂养的影响。研究结果表明，在制定精确的 P 喂养策略时，考虑奶牛养殖系统的类型非常重要，并且强调了饲料专业人员在减少 P 喂养方面的重要性日益增加。
