With a number of farmers having already started their breeding season, and many more following suit in the next few days, submission rates combined with good conception rates are essential to have an optimal six-week in-calf rate.
Farmers need to hit the ground running at the start of the breeding season to make this happen. They should aim to submit 90% of eligible cows within three weeks and to have all eligible cows intended for breeding submitted by six weeks after the mating start date.
An eligible cow should be a cow that has calved down in time. For any late calvers in the herd, a synchronisation programme might be an option to tighten up the calving pattern.
To limit the number of late calvers in the herd, farmers need to have a definitive start and end planned to the breeding season, aiming for 10-12 weeks of breeding.
These late calvers should be milked once-a-day until they are bred to reduce the recovery time post-calving. Any non-cycling cows that have calved over 42 days should be treated to ensure 100% submission rates as early as possible.
Farmers should continue to artificially inseminate until the number of non-bred cows are in line with the bull power on the farm.
In the last three weeks of the breeding season, farmers should be using short gestation bulls with good beef traits to ensure those cows calve down quickly.
Submission and conception rates
The three-week submission rate of 90% is critical in order to achieve a six-week calving rate of 90%, which is crucial to ensure long lactations and high levels of milk production.
To achieve the 90% three-week submission rate, farmers need to be submitting 4.3% of their herd each day at the beginning of the breeding season, which equates to five cows a day for a 100-cow herd.
The combining factors of submission rate (SR) and conception rate (CR) on six-week in-calf rate for cows is as follows:
60% CR
50% CR
40% CR
30% CR
90% SR
79
70
59
47
80% SR
73
64
54
42
70% SR
66
58
48
38
60% SR
59
51
42
33
There are two factors that affect the six-week in-calf rate: low submission rates deriving from cows not cycling or poor heat detection; and low conception rate deriving from the presence of uterine infection.
The target on farms should be to have 79% of cows in calve within the first six weeks of the breeding season and 100% of the heifers.
This is why it is crucial to keep up the momentum with submission rates over the next three weeks, in particular, to ensure that cows go back in-calf within the first six weeks of breeding.
Also, those cows that did not hold to their first serve or were missed have a second chance in the six-week window.
