Teat orifice stretchability associated with teat diameter gradient and milk yield in lactating cows

Abstract
SUMMARY: Teat canal stretchability was measured on 119 lactating cows from two dairy farms, using a probe. Diameter of one hind teat was measured by calipers at the proximal end of the teat and 20 mm above its distal end. Teat canal stretchability, teat diameter at the proximal end and teat diameter gradient were highly correlated with milk yield. Cows with higher teat diameter gradient (i.e., funnel-shaped teats) had higher teat canal stretchability values compared with the cows with lower teat gradient values (i.e., cylindrical teats). Stretchability of the hind teat canal was significantly greater than the stretchability of the fore teat canal.