Effects of liner compression on teat-end hyperkeratosis

The teat canal is an important barrier against microorganism invasion of the udder. The degree of teat-end hyperkeratosis (HK) is a dynamic condition. Development of HK is influenced by many factors: some animal dependent, some dependent from seasonal condition and some from milking management. In particular milking vacuum and liner compression (LC) can influence teat-end condition. A quarter-udder experiment was performed with four liners each applied one quarter of 75 Holstein cows for a period of 3 weeks. Teat-end HK was assessed weekly. The results of this study confirm that the risk developing HK increases with liners that apply greater pressure to the teat end when closed. The risk of developing HK was highly influenced by the duration of milking and initial teat-end HK score.