his program, this program is most effective in cyclic cows rather than in cows that have not resumed normal
estrous cycles following calving (anestrous cows). This program is recommended in herds where a high
percentage of cows are cyclic, such as herds with a high proportion of mature cows (≥ 3 years old) that
are > 60 days postpartum (dpp) at the initiation of the synchronization program. It is not recommended for
use in herds where cows are thin, or where a majority of the cows are less than 60 dpp at program initiation,
since there is a higher probability that these females will be anestrus.An additional disadvantage of the CO-Synch
program is that a proportion (~10%) of cows will exhibit estrus and ovulate between days -1 and 1 and
these animals will not conceive if strictly timed-AI is
used. Producers who have the labor and facilities to
accommodate estrus detection between days -2 and 1
can AI these cows that exhibit premature estrus.