Hoof trimming is a part of dairy farm management to provide better weight bearing surfaces and earlier detection of hoof injuries. In modern dairy farm situation by increasing milk production and other management indices the speed of hoof growth is higher and, more important, weight bearing surfaces are changed that resulted in demand of more accurate indices for detection of long toed cows. Finding such a cows is very difficult in large dairy herds and needs some criteria in addition to visual detection of the cows. Cows trimmed twice a year on 120 days after parturition and before drying, any delay in pregnancy resulted in increasing the gap between these two trimmings and possibly hoof overgrown that could result in different digital lesions. A new formula for detection of such a cows was improved and evaluated in this current study, based on this formula all cows with days in milk (219 ”time from successful insemination to drying” +Days Open) and higher with 140 days and less pregnancy were selected for hoof trimming. The study was done in a large (2200 milking cows) dairy herd with regular hoof trimming program. Two groups of cows (40 cows in each group) were selected. Group one cows selected in according to their long toes (visually detected). Group two cows selected on the above mentioned formula. Toe length, Heel height, Toe height and hoof angel were measured and compared between two groups using t-test and p values under 0.05 revealed as significant. Toe length (8.98 ± 0.74), heel height (4.81 ± 0.95), toe height (7.15 ± 0.79) and hoof angle (56.14 ± 7.6) were significantly higher in group two than group one (P<0.05). Results indicates that this formula have better potency in detecting cows with long toes than visual detection.

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