Mid-Season Breeding Decisions to Improve Farm Profitability
Type Media Article
By Michael Donoghue, B&T Dairy Adviser, Teagasc Galway/Clare
Most spring calving dairy herds are now entering the 5th week of their breeding season. All cows that have been selected for breeding in 2024 season should be been served at this stage. Any problem cows should have been scanned and remedial action taken as required. Replacement AI/ breeding if not already should be finished. As these late heifers will always be on the back foot and require a lot of time and cost to catch up the “early heifer”. When selecting beef AI or stock bulls use only easy calving and high Dairy Beef Index, DBI, for the remainder of the breeding season.
Length of Breeding Season
Over the last decade or so the quality of dairy breeding has improved dramatically, with the introduction of EBI. This is seen especially in the fertility improvement in dairy herds. Herds are calving more compactly at the start of the grass growing season. The question should now be asked how to take advantage of this better breeding, when do I want to finish calving in 2025?
Based on a gestation length of 283 days below gives a guide for expected calving date.
| AI service | Calving Date |
|---|---|
| 1st June | 11th March |
| 15th June | 25th March |
| 1st July | 10th April |
| 15st July | 24th April |
| 1st Aug | 11th May |
While there is no one case fits all most dairy farmers should be aiming to finish their breeding season between 1st July and 15th July. This will positively impact your farm profitability in 2025 by removing late calvers thus cows get more days in milk, especially if the herd dries off over the winter. Increasing calf value as the late calves tend to be lower value and have the most health problems. Finally even the late calvers in 2025 will have 4ish weeks before breeding to recover from calving thus they stand a far better chance of going in calf in 2025.
Cow Activity
During the 1st round of breeding there is always lots of cows in heat together, thus there is lots of activity/ mounting. So identifying cows in heat should be relatively straight forward. However as the breeding season moves into the 2nd and 3rd round there is a big drop of in activity/ mounts. On average during the 1st round we can get 40 to 50 mounts for a cow in heat but during the second this can drop to 10 to 15. So identifying cows in heat gets a lot harder. There is no single solution to this but some options to help with identifying cows in heat might include, using teasers bulls, keeping tails paint topped up, using bulls but continue to AI, heat detection systems/ collars.
Bull Power
A question often asked is how many bulls do I need? Below gives a guide to how many cows a bull can put in calve for a relatively compact spring calving herd
- 1 mature bull per 20 - 25 cows
- 1 young bull per 10 - 15 cows
The second part in determining how many bulls are required, is deciding when the bulls are been introduced to the herd and getting a handle on the fertility status of your herd.
| Breeding Cows | Submission Rate | Conception Rate | Cows in calf | Cows Not in Calf | Mature Bulls required | |
|---|---|---|---|---|---|---|
| Wk 0 | 100 | 100 | 5 | |||
| Wk 4 | 100 | 90 | 55 | 50 | 50 | 3 |
| Wk 7 | 100 | 90 | 50 | 73 | 27 | 2 |
| Wk 10 | 100 | 90 | 50 | 85 | 15 | 1 |
In the example above, if AI is just been used for the 1st round of breeding, submission rates are very good and conceptions are good. Then 3 bulls should be enough, if there are individual days with a lot of activity, cows on heat, then cows should be AI’ed rather than relying on the bulls. Also important is giving bulls a “day off” this will not only give the bulls a rest but also help to keep them keen when they are with the cows.
Bull Safety
Bull safety is always an issue but extra caution is required as we enter the last few weeks of the breeding season. Bulls can become more agitated and farmers getting lax around the bull as he has been with the cows a while. Make sure bulls are ringed, have a rope or chain on ring and have warning signs up. Ideally when breeding season is finished kill off the bulls or have a plan for somewhere safe to keep them.
We are effectively at half time in the 2024 breeding season and hopefully the 1st half has weent well. As always the 2nd half is critical and is more difficult. As we have to deal the distractions of other jobs especially silage making, less activity with cows and the problems of bulls. But with a strong focus on the last few weeks of the breeding season and good quality decisions, 2024 can be a successful breeding season.