Digital dermatitis (DD) is the most common infectious foot lesion affecting welfare and productivity of dairy cattle. The key to DD control programs is routine and frequent identification of DD lesions. The objective was to evaluate accuracy of detecting and scoring DD lesions in 3 milking parlor designs and in 3 alternative settings compared with scoring in the hoof trimming chute as reference. A total of 552 cows and 1,104 hind feet from 17 freestall farms were scored by 1 observer in the milking parlor and in 1 other setting: pen, headlocks, or management rail. After being scored in the milking parlor and at least 1 other setting, cows were examined in the hoof trimming chute, considered the gold standard. In every setting, all hind feet were inspected visually using a flashlight and without prior washing of feet. Agreement of the scoring settings was assessed using the 5 M-stage scoring system and a dichotomous absence (M0 or M0/M1) or presence (M1 to M4.1 or M2 to M4.1) system. At trimming chute inspection, 44% of feet had a DD lesion, with estimates of 11, 5, 2, 10, and 16% for M1, M2, M3, M4, and M4.1 lesions, respectively. Apparent DD foot-level prevalence at the milking parlor, pen, management rail, and headlocks was 28, 22, 16, and 22%, respectively. M-stages were less discernible in the pen, management rail, and headlocks (apparent prevalence of M1, M2, M3, and M4.1 was ≤1%) compared with the trimming chute and milking parlor. Agreement beyond chance between any scoring setting and trimming chute scoring ranged from 0.48 to 0.70 for the dichotomous scoring system (absence = M0/M1 vs. presence = M2 to M4.1). Diagnostic test performance varied greatly among DD scoring settings but, in general, it had low sensitivity (<70%) and high specificity (>93%) for detecting any DD lesion. Agreement and test characteristics were not affected by the type of milking parlor. Although the milking parlor and headlocks were the most reliable settings in which to detect DD, none of the settings were reliable enough to replace inspection of feet in the trimming chute. However, scoring the presence or absence of DD in the milking parlor, pen, management rail, and headlocks could be used to estimate within-herd DD prevalence, to improve DD surveillance through routine monitoring, and to evaluate effects of interventions at the farm level.

数字皮肤炎（DD）是影响奶牛福利和生产力的最常见的传染性足部病变。DD控制程序的关键是对DD病变的常规和频繁识别。目的是评估在3种挤奶厅设计和3种替代设置中对DD病变进行检测和评分的准确性，并与在修蹄斜槽中进行评分相比作为参考。一名观察员在挤奶厅和其他1种环境（笔，锁头或管理导轨）中对来自17个速冻农场的552头母牛和1,104只后脚进行了评分。在挤奶厅和至少其他1个环境中进行评分后，在修蹄斜槽中对母牛进行了检查，这被认为是黄金标准。在每种情况下，均使用手电筒目视检查所有后足，而无需事先洗脚。使用5 M阶段评分系统和二分式缺席（M0或M0 / M1）或存在（M1至M4.1或M2至M4.1）系统评估评分设置的一致性。在修整滑道检查时，有44％的脚患有DD病变，M1，M2，M3，M4和M4.1病变的估计分别为11％，5％，2％，10％和16％。在挤奶厅，围栏，管理导轨和挂锁处，表观DD脚患病率分别为28％，22％，16％和22％。与修整滑槽和挤奶厅相比，在笔，管理导轨和头锁中的M级难以识别（M1，M2，M3和M4.1的表观患病率≤1％）。对于二分式评分系统，任何评分设置和修整斜道评分之间的契合度在0.48至0.70之间（缺席= M0 / M1与存在= M2至M4.1）。在DD评分设置中，诊断测试的性能差异很大，但通常，它对检测任何DD病变的敏感性低（<70％）和高特异性（> 93％）。协议和测试特征不受挤奶厅类型的影响。尽管挤奶厅和前锁是检测DD的最可靠设置，但这些设置都不足以代替对修整斜槽中脚部的检查。但是，可以通过对挤奶厅，围栏，管理栏和上锁中是否存在DD进行评分，以估算畜群内DD的患病率，通过常规监测改善DD的监测，并评估农场一级干预措施的效果。 。93％）用于检测任何DD病变。协议和测试特征不受挤奶厅类型的影响。尽管挤奶厅和前锁是检测DD的最可靠设置，但这些设置都不足以代替对修整斜槽中脚部的检查。但是，可以通过对挤奶厅，围栏，管理栏和上锁中是否存在DD进行评分，以估算畜群内DD的患病率，通过常规监测改善DD的监测，并评估农场一级干预措施的效果。 。93％）用于检测任何DD病变。协议和测试特征不受挤奶厅类型的影响。尽管挤奶厅和前锁是检测DD的最可靠设置，但这些设置都不足以代替对修整斜槽中脚部的检查。但是，可以通过对挤奶厅，围栏，管理栏和上锁中是否存在DD进行评分，以估算畜群内DD的患病率，通过常规监测改善DD的监测，并评估农场一级干预措施的效果。 。没有一种设置足够可靠，足以代替对修整滑道中脚部的检查。但是，可以通过对挤奶厅，围栏，管理栏和上锁中是否存在DD进行评分，以估算畜群内DD的患病率，通过常规监测改善DD的监测，并评估农场一级干预措施的效果。 。没有一种设置足够可靠，足以代替对修整滑道中脚部的检查。但是，可以通过对挤奶厅，围栏，管理栏和上锁中是否存在DD进行评分，以估算畜群内DD的发生率，通过常规监测改善DD的监测，并评估农场一级干预措施的效果。 。