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The very first piece of advice we’d give is to take a look back over your last year's breeding performance.
What are the various aspects you could have improved on which may have made a small or large difference to how your spring calving season progressed?
Crucial areas of focus such as pre-breeding nutrition, heat detection, your choice of bulls, or even animal handling facilities, seem to be the main hurdles where farmers fall.
Identify where you think things could have been improved and put a plan in place to ensure you don’t incur the same issues this year.
On outfarms where the likes of maiden heifers may be put for the breeding season, heat detection is vital for many reasons in terms of improving their fertility.
If your breeding strategy is working, then your heifers should have the best genetic profile in your herd.
With that being the case, it is important to maximise fertility and the number of heifers that go in-calf successfully.
This gives them the chance to stay in the herd and improve the overall genetic profile even further.
Here are five tips to improve fertility in maiden heifers and maximise their conception rates.
1. Submission rates and heat detection
The submission rate achieved will be determined by heifers having reached puberty and having begun to cycle, then the ability of the farmer to identify heats so heifers can be submitted for AI.
A heat detection aid is almost essential in achieving high submission rates, particularly with heifers.
Tail paint or scratch cards can be effective and help identify heifers that have been risen on and in heat.
Vasectomised bulls fitted with a chinball harness or a Moocall HEAT collar have proven very successful for heat detection in heifers, the advantage of a system like Moocall HEAT is that it will determine the onset of standing heat then giving the optimum time to serve.
2. Target liveweight
Heifers should be well grown at the time of breeding. Set weight targets for your herd and be sure to stick to them.
Weigh the heifers periodically (weaning, housing, turnout and pre-bulling) to ensure they are on track to reach target bulling weight, that way you can alter the feeding rate if heifers are coming in too light or are overfed.
The guideline for dairy heifers is that they should have reached 60% of their mature liveweight at the time they are due to be bred.
3. Timing of AI
Correct timing of AI is important to maximise conception rates to artificial insemination.
The best guideline to follow is insemination 12 hours after the onset of standing heat.
To follow this guideline, you must have a good heat detection method or system to identify the standing heat.
Adequate conception rates can be achieved in systems where AI is only possible once a day. In these cases, it is best to AI slightly early rather than leaving it too late.
When inseminating once a day, it is best to AI even if activity has been detected and is ongoing rather than leaving it another 24 hours when ovulation may already have occurred and it is too late.
If using sexed semen, it is definitely advisable to AI twice a day, with the optimum time to AI being 14 to 20 hours after onset of standing heat.
4. Synchronisation
Synchronisation can be a useful management tool to maximise the number of heifers submitted for AI early in the breeding season.
Breeding and subsequently calving heifers earlier in the season will give them extra time and a better chance of going back in calf again during their first lactation.
There are different synchronisation protocols and methods that have proven to give good results, with up to 100% submission rates and conception rates of 70% being achievable.
A prostaglandin injection-based approach is quite popular and cost effective. This protocol involves administering an intramuscular prostaglandin injection and, three to five days later, any heifers showing signs of heat can be inseminated.
Any heifers that do not come into heat after the first injection then receive a second injection 11 days later. Again, they should be observed for heat behaviour another three to five days post-injection and inseminated based on standing heat detection or they can be fixed-time AI-ed 72 to 96 hours after the injection.
It is important to note that this approach will not work if heifers are not already cycling.
5. AI technique
Heifers can prove more difficult to AI than cows due to the small cervix size, meaning a highly skilled and trained technician is necessary to achieving good conception rates.
AI sheaths specially designed for heifers are available that can make the job easier.
If doing DIY AI on heifers, be sure to only thaw one straw at a time, as it may take longer than anticipated and you don’t want to rush the process due to having another gun loaded and ready to go, particularly if you are using sexed semen.
For AI, a vasectomised bull fitted with a Moocall HEAT collar is proven to increase submission rates and reduce the number of missed heats, while saving on the time spent visually observing cows for signs of heat.
Moocall HEAT sends a message to the farmer once the bull detects a cow in standing heat, giving an optimum time to serve the cow.
If using a stock bull, you can be rest assured, as the collar will not only detect when heats are present but also that your bull has served the cow.
This provides you with accurate calving due dates for the spring, but also identifies any non-cycling or problematic cows within the first few weeks of breeding.
As well as being one of the most affordable heat detection technologies on the market, Moocall also stands over being able to achieve a 96.5% submission rate within the first three weeks of breeding.
The system also provides the farmer with complete control and tracking of their breeding performance through the Moocall Breedmanager App.
Check out this video to see just exactly how successful Moocall HEAT works for farmers using artificial insemination:
For more information, please contact the Moocall team on 01-969 6038 or visit the website https://www.moocall.com/heat/.
