INFLUENCE OF MACHINE MILKING ON TEAT CONDITION OF DAIRY COWS

The paper deals with changes of some teat parameters of dairy cows caused by machine milking. Ultrasonographic scanner GE Medical Systems LOGIQ 100 PRO with linear array VE 5 - 5 MHz probe was used for scanning the teats. Scanning was conducted on a dairy farm at the Agricultural High School in Krizevci on 27 cows, nineteen of them of Holstein Friesian breed, 2 Simmental breed, 4 SimmentalxHolstein crossbred and 2 SimmentalxRed Holstein crossbred. The cows were housed in a free stall barn and milked in a herringbone 2x3 milking parlour with Alfa-Laval milking system with Duo vac milking units. Teat scanning was done just before morning milking and immediately after milking on the right side of the udders for front and rear teats. The following parameters were measured: teat canal length (TCL), teat end width (TEW), teat cistern width (TCW) and teat wall thickness (TWT). As fifth and sixth parameter ratio between teat canal length and teat end width (TCL/TEW), and teat cistern width and teat wall thickness (TCW/TWT) was calculated. Length of teat canal for the front right teat increased in average for 1.7 mm (15.4%) after milking, and 2.6 mm (26.3%) for the rear right teat. Teat end width of the front and rear right teat increased after milking for 0.8 mm (3.7%) and 0.7 mm (3.3%), respectively. Mean teat cistern width of the front right teat decreased after milking far 2.7 mm (24.4%) while for the rear right teat mean decrease was 2.9 mm (25.8%). Teat wall thickness of the front and rear right teat increased after milking for 0.5 mm (7.86%) and 1.1 mm (15.8%) respectively The ratio between teat canal length and teat end width changed for the right front teal from 0.525 before milking to 0.584 after milking, while for the right rear teat it changed from 0.501 to 0.603. The ratio between teat cistern width and teat wall thickness changed far the right front teat from 1.544 before milking to 1.082 after milking, and for the right rear teal from 1.54 to 0.987.