Meyer S W, Weishaupt M A, Nuss K A
Department of Farm Animals, Vetsuisse-Faculty, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland.
J Dairy Sci. 2007 Feb;90(2):670-6. doi: 10.3168/jds.S0022-0302(07)71549-7.
The manner in which the claws contacted the ground at the walk was evaluated in 18 healthy heifers. The animals were filmed before and after claw trimming while walking on a treadmill using high-speed cinematography (500 frames/s). For each limb, 4 consecutive steps were recorded from a side and a frontal plane. The objectives of the study were to evaluate 1) the order of claw contact with the treadmill surface, 2) the initial claw contact area, and 3) the effect of trimming on claw contact patterns. The heifers placed their front feet on the ground in a plane sagittal to the shoulders, whereas the hind feet were advanced more toward the median plane. Before trimming, the lateral claws contacted the ground before the medial in 83% of front and 100% of hind limbs. Trimming changed the percentage to 92% in the front and to 97% in the hind limbs. The percentage with which the heel of the lateral claws became the region of initial contact with the ground increased from 47 to 64% in the front feet and from 50 to 78% in the hind feet. In the medial claws of the forelimbs, claw trimming shifted the region of initial contact from the toe to the abaxial wall and heel. In the hind limbs, the main region of initial contact of the medial claws became the abaxial wall. Weight bearing by the medial claw became visibly apparent only during the midstance, propulsion, and push-off phases. "Heel first" contact of the lateral claws in the front and hind limbs may be the normal gait pattern in cattle. On hard surfaces, this pattern may lead to overload and predispose to disease, especially in the hind limbs.
在18头健康小母牛中评估了行走时爪子与地面接触的方式。在使用高速摄影（500帧/秒）在跑步机上行走时，对这些动物在修蹄前后进行了拍摄。对于每只肢体，从侧面和正面平面记录连续4步。该研究的目的是评估：1）爪子与跑步机表面接触的顺序；2）初始爪子接触面积；3）修蹄对爪子接触模式的影响。小母牛将前脚放在与肩部矢状面平行的平面上着地，而后脚则更向正中面推进。修蹄前，83%的前肢和100%的后肢外侧爪子比内侧爪子先接触地面。修蹄后，前肢的这一比例变为92%，后肢变为97%。外侧爪子的后跟成为与地面初始接触区域的比例在前脚从47%增加到64%，在后脚从50%增加到78%。在前肢内侧爪子中，修蹄使初始接触区域从脚趾转移到轴外壁和后跟。在后肢中，内侧爪子的主要初始接触区域变为轴外壁。内侧爪子仅在支撑中期、推进期和蹬离期明显承重。前肢和后肢外侧爪子“脚跟先着地”的接触方式可能是牛的正常步态模式。在坚硬表面上，这种模式可能导致过载并易引发疾病，尤其是在后肢。
