Prevalence of Teat End Callosity in East Azerbaijan Dairy Herds

摘要

Teat end callosity is a very important problem which affects cows in the farms of Iran and many other countries. This disease mainly caused by the over milking and defects in the milking machine. In this survey, we focused on the four large dairy Holstein herds consist 860 dairy cows at around of Tabriz (North-west of Iran) and we assisted the teat end callosity or hyperkeratosis and its relation with milking frequency per day. In the herds A (n = 300) and B (n = 160), cows were milked 3 times day-1. In the herds C (n = 162) and D (n = 190) cows were milked 2 times day-1. Prevalence of the teat end hyperkeratosis in the herds of A and B were recorded as 14.1%. In the herds of B and C this prevalence was 12.3%. Also, according to the Wilson?s grading schedule the grades of 2 and 3 of hyperkeratosis more prevalent between the cows with 3 times milking day-1 than cows with 2 times milking day-1. Statistical analyses indicated significant differences between the herds of A, B (3 times milking day-1) and herds of C, D (2 times milking day-1). In conclusion, according to the results, significant relationship exists between the cow?s teat end callosity and milking frequency/day.