Effect of milking vacuum level and overmilking on cows teat characteristics

The influence of milking vacuum and milk flow level (resp. detachment level) on cows teat characteristics were studied in four experiments. The MIXED procedure was used to test treatment effects on the level of teat length,teat thickness at the base and half-way between the teat end and the base of udder,teat canal length,teat end width,teat wall thickness,teat cistern width after milking and on differences between these teat characteristics measured before and after milking. A total of 51 cows were included in all experiments. All the cows had clinically healthy udders. Some cows were involved in two or more experiments. Finally,330 teat measurements of 165 cows were taken and statistically processed. Vacuum and milking with or without overmilking significantly (P 0.05-0.001) influence monitored parameters. Milking vacuum has an influence on two of three measured external teat parameters: teat diameter measured at the base of the teat and half-way between the udder base and the teat tip. Change in teat length measured before and immediately after milking was higher when higher vacuum of 45 kPa was used. Detachment level also has an influence on teat proportions. Overmilked teats were longer and narrower compared to non-overmilked teats. Interaction between milking vacuum and detachment level influences external teat parameters as well.