Department of Environmental Horticulture, York College of Pennsylvania, York, Pennsylvania, USA.
The Dickinson College Farm, Carlisle, Pennsylvania, USA.
Med Vet Entomol. 2023 Mar;37(1):37-46. doi: 10.1111/mve.12605. Epub 2022 Aug 23.
The beef industry endures major economic losses from a complex of flies that feed on bovine blood and mucus. For cattle on pasture, the most important of these pests are horn flies (Haematobia irritans [L.] [Diptera: Muscidae]) and face flies (Musca autumnalis [Diptera: Muscidae] De Geer). Pasture dragging to spread manure pats has been promoted as a management tactic for these species because their larvae inhabit bovine manure pats, but the efficacy of this practice has not been empirically validated. Spreading pats might promote fly mortality through desiccation or overheating, but these processes are weather-dependent and warrant testing in disparate climates. We evaluated pasture dragging effects while monitoring for weather interactions throughout nine experiment rounds in summers of 2018 and 2020 in Pennsylvania, USA. The manure spreading treatments increased pat surface area up to 300% but failed to significantly reduce emergence of horn flies and face flies as compared to controls. In contrast, precipitation and temperature were significant predictors in fly emergence models. Surprisingly, face fly emergence was significantly elevated in dragged pats twice in 2020. These data call for a reevaluation of pasture dragging as a management technique for horn flies and face flies across a range of climates.
牛肉行业因一种以牛血和黏液为食的苍蝇而遭受重大经济损失。对于牧场牛来说，这些害虫中最重要的是角蝇（Haematobia irritans [L.] [双翅目：蝇科]）和秋蝇（Musca autumnalis [双翅目：蝇科] De Geer）。牧场拖动传播粪饼已被推广为针对这些物种的管理策略，因为它们的幼虫栖息在牛粪饼中，但这种做法的效果尚未通过经验验证。传播粪饼可能会通过干燥或过热来促进苍蝇死亡，但这些过程取决于天气，并且需要在不同气候下进行测试。我们在美国宾夕法尼亚州的 2018 年和 2020 年的九个实验轮次中监测天气相互作用的同时，评估了牧场拖动的效果。与对照相比，粪便传播处理将粪饼表面面积增加了高达 300%，但未能显著减少角蝇和秋蝇的出现。相比之下，降水和温度是苍蝇出现模型中的重要预测因素。令人惊讶的是，2020 年有两次秋蝇在拖动的粪饼中出现显著增加。这些数据呼吁重新评估牧场拖动作为一种在不同气候条件下控制角蝇和秋蝇的管理技术。
