Hyperkeratosis
Hyperkeratosis is also known by a variety of names such as teat end erosions, teat end eversions and fibrous or callous rings. It causes inflammation and stress on the teat end.

Hyperkeratosis is commonly associated with overmilking. There is increased incidence and severity on front teats because front teats generally produce less milk and are more likely to be overmilked. Higher producing cows also may be more susceptible to hyperkeratosis. The condition tends to disappear during the dry period.