RESUMO
Cattle lameness is one of the biggest problems dairy producers are facing today. Maybe regular hoof trimming is considered as one of the most efficient and easy way to save normal function of the hooves. According to Toussaint Raven method of functional hoof trimming, toe length is the most determinant of the procedure. Seventy mm from the coronary band at the toe region is considered as a safe distance for performing the first cut, but following this cut, lameness due to the trauma to sensitive tissue in some animals is a common problem. The current anatomic study was performed to determine the proper distance between cutting surface on dorsal wall of the hoof and coronary band. The distance between coronary band and the terminal margin of the sensitive tissue, after mid-sagittal section, considered as beta length. Three hundred hooves collected from slaughtered cattle were divided into three groups, according to the breed [A: registered Holstein, B: cross breed, C: native breed]. The most important determining factor in different breeds were their weight as animals in group A weighted more than 550 kg, Group B less than 550 and more than 400 and group C weighted less than 400 kg. Mean [mm] +/- SD of beta length were 62.2 +/- 8.46, 57.3 +/- 8.12 and 49.5 +/- 7.75 in groups A, B and C, respectively; which was significantly different from each other [P<0.05]. beta length in lateral digits were slightly longer than medial digits but the difference were not significant. With regard to upper limit of deviation in beta length it seems that 80 mm length is safer in registered Holstein cattle