A dairy farmer in overalls and a plaid shirt makes notes on a clipboard while standing next to Holstein dairy cows in a barn. Overlaid text asks 'Do we still need the AM-PM Rule for the artificial insemination of cattle?' and is attributed to Ryan Sterry.

Do we still need the AM-PM Rule for the artificial insemination of cattle?

For nearly eighty years dairy producers have been indoctrinated in the use of the AM-PM rule for artificial insemination (AI) of cattle. The AM-PM rule dictates that a cow should receive AI 12 hours after first being observed in estrus. If a cow is seen in estrus in the AM she should receive AI that PM, and cows seen in estrus in the PM should receive AI the following AM.

Dairy