Cows from the TAIþNS group received TAI on Day
11 of the BS, followed by NS until the end of the BS; TAIþEDþNS: cows in the TAIþEDþNS received TAI on Day 11, then were observed for estrus twice a day with
AI 12 hours after ED until Day 45 of the BS, followed by NS until the end of BS; EDþNS: cows were artificially inseminated after estrous detection during the first
45 days of the BS followed by NS until the end of the BS; NS: breeding was exclusively by NS throughout the entire BS. BS, breeding season; ED, estrus detection;
NS, natural service; TAI, timed AI.