What is the relationship between hyperkeratosis and mastitis in dairy cows? Teat-end hyperkeratosis (THK) is a highly prevalent teat pathology affecting dairy cows. It is characterized by a hyperplasia of the keratin layer of the teat orifice as a response to chronic stimuli. Using a severity score from 1 (less severe) to 4 (most severe), studies have found a prevalence between 21% and 46% for grade 3 and between 12% and 19% for grade 4.
Anatomical and physiological mechanisms at the teat orifice play a fundamental role in protecting the mammary gland from pathogens. The stratified squamous cell epithelium acts as a physical barrier, fatty acids have bacteriostatic effects and the muscular layer keeps the teat orifice closed in between milking.
Is hyperkeratosis a risk factor for clinical mastitis?
Different factors at the cow level such as teat shape and position, stage of lactation, parity, … have been associated with the development of THK. Factors at the herd level such as milking management and equipment settings, have also been linked to THK.