Breeding Season: How Long is Too Long

How long should your breeding season be?

The cattle business is amazing in its diversity of geographical locations and management styles. Every ranch must adapt to their environment and resources and strive to be a competitive producer of calves and feeder cattle. One of the many decisions to make each year is, how long should your breeding season be?

One quick answer is, not much different than last year. Cows will need 30 to 90 days after calving to get themselves ready to conceive again. The length of time will depend on many factors that include nutrition, body condition, age, easy of calving and even photo period. I have seen some low pregnancy rates when the breeding season has been shortened by 10 days from one year to the next. If pasture conditions are tough and there were a high percentage of young cows and late calvers in a herd, be prepared for more open cows at pregnancy testing if the breeding season is shortened. If cow numbers must be reduced due to limited forage supply, this is one way to get this done.

Another way to manage the breeding season is to ultrasound pregnancy test cattle at a strategic time so fetuses can be aged. Bulls can be left in longer or not pulled at all. This has been done successfully on many ranches. Fetal aging is more accurate when done sooner rather than later. For example, 40 to 120 day (4 month) fetuses can be more accurately identified than 5 to 7 month old fetuses. Most of the cows can be more than 120 days pregnant at pregnancy testing, it is just the late calvers that need to be accurately identified and removed from the herd if necessary. So, pick a pregnancy testing date that gives you the greatest strategic value for your work. Like most things, it is usually sooner than later!

Some ranches leave bulls in with the cows until pre-conditioning or weaning time and pregnancy test with ultrasound equipment and still maintain a 63-day breeding season. Quite often very little change is necessary to ranch management to get the cows pregnancy tested at an earlier date. The ranch is rewarded for these efforts with better cull cow prices and better information about the year’s breeding season and nutrition program. The late calving cows may be sold as pregnant cows to another ranchers that calves later. A note of caution is to watch yearling bulls. If you decide to leave bulls in for the a longer season, keep an eye on the condition of yearling bulls. You may need to pull them sooner.

The goal is always to be to get as many cows bred early in the calving season as possible. Ranch profitability depends on this. It also depends on making some other good strategic decisions and ultrasound pregnancy testing with fetal aging is one of these. - Dr. Andrew Bronson