Role of the sensitivity of detection of oestrus in the submission rate of cows treated to resynchronise oestrus

Abstract

Objective: To determine if failure to detect oestrus in cows treated to resynchronise oestrus leads to fewer cows being inseminated than are truly in oestrus. Procedure: Cows in three herds were enrolled in a controlled breeding program that involved synchronisation of oestrus for a first round of artificial insemination (AI) followed by resynchronisation for a second round of AI. Just before oestrus was expected at the second round of AI, aids for the detection of oestrus were fitted, which included pedometers, radiotelemetric transmitters (HeatWatch®), tail-paint and heat-mount detectors. Milk samples were collected at the second round of AI (day 33, herds A and B; day 35, herd C of the tr..