Abstract：
Increasing shortages and costs of common bedding materials have led dairy farmers in Sweden to consider using recycled manure solids (RMS), which are readily available and low cost, as an alternative bedding material. The main risks are effects on udder health and milk quality, but RMS could also affect animal welfare and claw health. The advantages and disadvantages of using RMS bedding have not been fully investigated, and findings in other countries cannot be directly applied to Swedish conditions and climate. This observational cross-sectional study investigated the use of RMS as bedding, regarding associations with certain aspects of animal welfare, herd health, milk quality, and bedding costs in Swedish dairy herds. Thirty-four dairy farms using RMS or wood shavings/sawdust (each n = 17) were compared. Each farm was visited 2 times during the housing period from 2020 to 2021, once from October to December and once from March to May. Dairy barns were observed, animal welfare was assessed, and freestall dimensions were measured. Farm owners were interviewed about housing system characteristics, herd performance, and herd management. Data on milk production and herd health were obtained from the Swedish official milk recording scheme for the indoor period from October to March. The prevalence of claw disorders and abnormal claw conformation were collected from the national claw health database for the period from October to May. On each farm visit, composite samples of unused bedding outside the barn and used bedding material from the freestalls, respectively, were taken for total bacterial count and DM analysis. Samples of bulk tank milk for determination of total bacterial count were taken in connection to the visits. In addition, samples of unused and used bedding material and manure from alleys for analysis of 3 Treponema species associated with digital dermatitis (DD) were gathered and analyzed. Total bacterial count was significantly higher in unused (8.50 log10 cfu/g) and used RMS bedding (9.75 log10 cfu/g) than in wood shavings/sawdust (used 4.74; unused 8.63 log10 cfu/g), but there were no significant differences in bulk milk total bacterial count (median 4.07 vs. 3.89 log10 cfu/mL) or SCC (median 243,800 vs. 229,200 cells/mL). The aspects of animal welfare assessed did not differ significantly between the 2 bedding systems, whereas the prevalence of total claw disorders (25.9% vs. 38.0% of trimmed cows), dermatitis (6.9% vs. 16.2% of trimmed cows) and sole ulcers (2.0% vs. 4.0% of trimmed cows) were significantly lower in the RMS herds. Treponema spp. were not detected in unused RMS material, but all RMS herds had presence of DD recorded at foot trimming. An economic assessment based on the interview results and price level from winter 2021 revealed that the costs of RMS bedding varied with amount of RMS produced. Thus, RMS is a potential alternative bedding material for dairy cows in Sweden and can be a profitable option for large dairy herds. However, the high level of total bacteria in the material requires attention to bedding and milking routines as well as regular monitoring of herd health.
摘要：
常见垫料材料的短缺和成本的增加导致瑞典的奶农考虑使用回收的粪肥固体（RMS），容易获得和低成本，作为替代床上用品。主要风险是对乳房健康和牛奶质量的影响，但RMS也会影响动物福利和爪子健康。使用RMS垫层的利弊尚未得到充分研究，和其他国家的发现不能直接适用于瑞典的条件和气候。这项观察性横断面研究调查了使用RMS作为垫料与动物福利某些方面的关联，牛群健康,牛奶质量,和瑞典奶牛群的床上用品成本。比较了34个使用RMS或刨花/木屑的奶牛场（每个n=17）。在2020-2021年的住房期间，每个农场都被访问了2次，一次在10月至12月，一次在3月至5月。观察到奶牛谷仓，动物福利进行了评估，并测量了自由失速尺寸。农场主接受了关于住房制度特点的采访，羊群表现，和羊群管理。有关牛奶生产和牛群健康的数据来自瑞典官方10月至3月的室内牛奶记录计划。从该时期的国家爪健康数据库中收集了爪障碍的患病率和异常的爪构象，十月-五月。每次农场参观，谷仓外未使用的床上用品和免费摊位使用的床上用品的复合样品，分别,进行细菌总数和干物质分析。在访问中采集用于测定总细菌计数的散装罐奶样品。此外,收集并分析了未使用和使用过的床上用品和小巷中的粪便样品，以分析与指性皮炎（DD）相关的3种密螺旋体。未使用的细菌总数（8.50log10cfu/g）和使用的RMS垫层（9.75log10cfu/g）明显高于刨花/锯末（使用的4.74；未使用的8.63log10cfu/g），但散装牛奶总细菌计数(中位数4.07对3.89log10cfu/mL)或体细胞计数(中位数243,800对229,200个细胞/mL)没有显著差异.评估的动物福利方面在两个床上用品系统之间没有显着差异，而全爪障碍的患病率(25.9%与修剪奶牛的38.0%)，在RMS牛群中，皮炎（6.9对16.2％的修剪母牛）和单发溃疡（2.0对4.0％的修剪母牛）明显较低。密螺旋体属。在未使用的RMS材料中未检测到，但是所有RMS牛群在足部修剪时都有DD记录。根据2021年冬季的采访结果和价格水平进行的经济评估显示，RMS床上用品的成本随RMS的产量而变化。因此，RMS是瑞典奶牛的潜在替代床上用品，可以成为大型奶牛群的有利可图的选择。然而,材料中细菌总量高，需要注意床上用品和挤奶程序，并定期监测畜群健康。
