VARIATION IN DISTANCES AMONG TEATS OF HOLSTEIN COWS - IMPLICATIONS FOR AUTOMATED MILKING

Distances among teats were measured immediately prior to and immediate ly following milking in 912 lactations of 506 Holstein cows to assess variation due to age (parity), stage of lactation, year, and observer. Data were used to simulate success or failure to attach by the Gascoi gne Melotte robotic milker. Distance between front teats premilking wa s nearly twice that for rear teats. When attachment of the cluster to an udder with a particular set of teat distances was simulated, excess ive distance between front teats was the most frequent cause of attach ment failure for third and later parities. For first parity, extremely narrow distance between rear teats was the most frequent cause of pre dicted attachment failure. Reduction in teat distances because of milk ing was proportionately much greater for distance between rear teats ( 45 to 50%) than for other tear distances (25 to 29%). In a study of 10 Holstein cows measured at milking and at 0, 6, 8, and 12 h after milk ing, distances among teats increased linearly with time elapsed postmi lking. Electronic storage of a profile of a cow for teat distance and adjustments for milking interval and stage of lactation can increase c hances for successful cluster attachment.