Laven L J, Margerison J K, Laven R A
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
N Z Vet J. 2012 Mar;60(2):123-8. doi: 10.1080/00480169.2011.644215.
The aim of the study was to validate the use of a portable ultrasound machine for monitoring sole thickness by investigating the agreement between ultrasound and electronic calliper measurement of distance from the external to the internal sole surface (sole thickness) and the distance from the external sole surface to the distal phalanx (DP).
Distal limbs were collected post-mortem from 24 dairy cows. Measurements were made using a portable ultrasound machine (Mindray DP 6600) on both claws of the right hind and left front feet at the tip of the distal phalanx (site 1) and 25 mm towards the heel (site 2). DP and sole thickness were measured at each site. The limbs were then frozen and sectioned, and the same parameters measured using electronic callipers. The limits-of-agreement between the two methods were investigated, and receiver operator characteristic (ROC) analyses undertaken.
Ultrasound images were obtained for 92 out of 96 claws. For sole thickness, as measured using callipers, the best correlation was with ultrasound-measured DP at site 1 (r=0.77). The mean difference between these two measures was 2.5 (SEM 0.15) mm and the range of the 95% limits-of-agreement was 4.2 mm. ROC analysis showed that a claw with an ultrasound-measured DP of <7.0 mm was >11 times more likely to have a sole thickness <5 mm than ≥ 5 mm, while a claw with an ultrasound-measured DP of >8.25 mm was 4.5 times more likely to have a sole thickness ≥ 5 mm than <5 mm. Soles could therefore be categorised as thin (DP < 7 mm), marginal (DP 7-8.25 mm) or adequate (DP >8.25 mm) using this ultrasound machine.
Examination of the claws of dairy cows using a basic portable ultrasound machine is sufficiently accurate for use in monitoring mean sole thickness in a group of animals. On an individual basis, measurement of DP can be used to categorise soles as thin, marginal or adequate.
The measurement of DP using portable ultrasonography can be used to evaluate the role of sole thickness in clinical lameness outbreaks, and as a research tool to monitor the dynamics of claw parameters over time.
本研究的目的是通过调查超声测量与电子卡尺测量从蹄底外部到内部表面的距离（蹄底厚度）以及从蹄底外部表面到远节趾骨（DP）的距离之间的一致性，来验证便携式超声仪用于监测蹄底厚度的有效性。
从24头奶牛尸体上采集远端肢体。使用便携式超声仪（迈瑞DP 6600）在右后蹄和左前蹄的两个蹄爪上，于远节趾骨顶端（部位1）以及向蹄跟方向25毫米处（部位2）进行测量。在每个部位测量DP和蹄底厚度。然后将肢体冷冻并切片，再使用电子卡尺测量相同参数。研究了两种方法之间的一致性界限，并进行了受试者工作特征（ROC）分析。
96个蹄爪中有92个获得了超声图像。对于使用卡尺测量的蹄底厚度，与部位1处超声测量的DP相关性最佳（r = 0.77）。这两种测量方法的平均差异为2.5（标准误0.15）毫米，95%一致性界限范围为4.2毫米。ROC分析表明，超声测量的DP < 7.0毫米的蹄爪，其蹄底厚度 < 5毫米比≥ 5毫米的可能性大11倍以上；而超声测量的DP > 8.25毫米的蹄爪，其蹄底厚度≥ 5毫米比< 5毫米的可能性大4.5倍。因此，使用这种超声仪可以将蹄底分为薄（DP < 7毫米）、边缘（DP 7 - 8.25毫米）或合适（DP > 8.25毫米）。
使用基本的便携式超声仪检查奶牛蹄爪对于监测一组动物的平均蹄底厚度足够准确。就个体而言，测量DP可用于将蹄底分类为薄、边缘或合适。
使用便携式超声检查测量DP可用于评估蹄底厚度在临床跛行爆发中的作用，并作为一种研究工具来监测蹄爪参数随时间的动态变化。
