As the spring calving period winds down for many farmers, attention will turn to breeding.
For herds where calving starts in February, breeding will now be underway.
When it comes to herd management during the breeding season, outlined below are some things to keep in mind.
1. Grouping cows for breeding
In herds where heifers are normally retained for breeding, replacements should be bred from the cows, weaning the heaviest calves each year.
They should also be bred from cows that calve in the first half of the calving period. These animals are usually more fertile and fertility is an extremely heritable trait within cow families.
Late calving cows should be run with a stock bull possessing more terminal traits, or bred to a terminal sire through AI.
If there is only a handful of late cows, consider running these animals with maiden heifers, as replacements are usually bred to easy calving, short gestation bulls.
A short gestation bull could help pull these cows forward for next year.
2. Limiting cow numbers with young stock bulls
Young bulls in their first breeding season need careful management. Too many cows can cause fertility problems.
As a rule of thumb, give the bull one cow per month of age. For example, an 18-month-old bull should get no more than 18 cows, and a 20-month-old bull should get no more than 20 cows.
3. Good grass and mineral supplementation
Prioritise good-quality grazing swards for cows during the breeding season. Keep a close eye on the number of days ahead of cows.
If grass is running tight, consider strip grazing some silage ground.
During the breeding season, it is important to keep cows on a steady diet. Mineral supplementation is also important and should be kept in mind.
4. Watch the bull for breeding activity
Watch the bull when turned out to cows; check he is mounting properly and following animals in heat.
Watch the bull at least twice daily, spending 15 to 20 minutes observing the animal on each check.
Always keep safety in mind, so don’t get too close to the bull.
5. Note when cows are served and the date
As cows are served to AI, or you see the bull mounting, note tag numbers and record the service date. Smartphones make recording tags easy.
Watch for repeats around 18 to 21 days after cows are served. If there are a lot of cows repeating, there may be an issue with the bull’s fertility.