The effort put in to breeding for the  month of May will pay dividends next spring, with the aim of maximising the 6 week calving rate which is a big driver of production and profitability in our spring calving grass based systems.  

Heat detection and submission rates 

Efficient heat detection will ensure cows that are in heat are presented for AI and  not being missed. Achieving this is easier in the first 3 weeks as activity is at its highest. Have a ball park figure for the average number of cows you should be submitting each day – divide the number of eligible cows by 20 to give a rough target for each day. If this target is not being reached it means that cows are potentially being missed or that cows are not coming in to heat. Either way investigation may be required to resolve. Ensure the heat detection method is appropriate for the situation. Tail paint works very well when there are 3 or more in heat per day. A neat narrow strip of paint will make rubbing off easier which is what we want. Scratch cards work better when number of animals in heat are lower and in heifers which are lighter and have less rubbing power.  

 

   

 

 

The FarmOps app provides real time analysis to help you stay on tract during the critical time of breeding. 

Heat detection and conception rates

Accurate heat detection will ensure the majority of cows are actually on heat when inseminated, giving them the best chance of conceiving. The graph below demonstrates the window for timing of AI with conventional and sexed semen.

Accurate timing is critical for sexed semen – guideline is 12 to 20 hours after the start of standing heat.

• ·        Sexed semen will not survive as long in the cow as conventional – avoid inseminating cows that are too fresh. Signs of heat need to be gone off the cow.
• ·        Sexed semen will work later in the heat than conventional – sexed semen has already gone through the process of capacitation during the sexing process, which means the sperm cells are ready to fertilize.  This process takes 8 to 10 hours and takes place in the cow for conventional semen.

 

 

Nutrition and Body Condition

This year’s spring has been in complete contrast to the spring of 2024. Grazing conditions have been excellent and the only barrier to cows being out full time has been grass availability. While the weather last spring was appalling, cows were fed on well with concentrates, also production was well down, this combination led to cows being in reasonable body condition and energy status resulting in reasonable good reproductive performance overall.

This year production is well up resulting in an increased energy demand on cows. For this month, as breeding is in full swing and cows are at peak, ensure their energy demands are being met and keep an on body condition. Once a day milking is a useful strategy to reduce energy demand in cows that are struggling for body condition. Milk once a day and feed twice a day until after they are bred. Avoiding cows that are struggling for body condition is one of the critical criteria when selecting cows for sexed semen. See below for full criteria.

Also displayed below is analysis from ICBF and Teagasc on national  first service inseminations for heifers (Parity 0) and cows (Parity 1 – 5). There are 2 take away messages from this analysis.

1. Heifers are the best candidates for sexed semen.  They have a higher pregnancy than cows and the gap to sexed is close (-4.8%)

2. Younger cows are better candidates than 5^th plus lactations. 1st lactation animals actually had the highest pregnancy rate, however they must fulfill all criteria to be eligible for sexed.

 

 

Repeats in heifers following synchronisation

Finally, the window for repeats in heifers following synchronisation will arrive later this month. The average pregnancy rate for heifers following first insemination with AI is illustrated in the previous graph – conventional 66% and sexed 61%. 50% of farms will achieve above this while 50% will be below. When it comes to repeats in heifers following synchronisation – hope for the best but plan for the worst. Over reliance on stock bulls that have no work done up to this point can end badly. The best approach  is to run the bull(s) from day 2 to 16, then remove the bull and apply scratch cards +/- crayon and commit to heat detection and inseminating the heifers during the repeat window of 18 to 24 days. The bull can be reintroduced around day 23  as activity declines. The next window for repeats will be between day 36 and 48 and the bull or bulls should handle this window depending on ratio.

 

Using beef early in the breeding season

The ensure you are breeding elite dairy females dairy semen should be avoided on poorer cows in the herd. Particularly high SCC count cows, lame cows or cows performing poorly within your herd. Even if these cows come cycling early in the breeding season you should aim to use beef semen on these cows. When selecting a beef bull you should aim to use a bull suitable on calving ease for the cow type and maximise the genetic potential. So early in the breeding season, an example of a beef bull team that will improve calf quality and value:

·        1st lactation cows - AA8472 TUBRIDMORE TWOMEY and HE5455 BARWISE 1 RICOCHET PP

·         2^nd to 3^rd lactation cows - AA2309 ST AODAIN L MASTER  and AU4683 TURLOUGHMORE MAGNIFICENT

·        Mature cows – BB7272 BBG HYBRIDE, LM9379 SHANNON STAN and CH6490 ORBI

Using beef AI at start of the breeding season will allow you generate dairy replacements from your best females and allow you produce high quality beef calves. Improving the overall value of your calf crop.

 

Have a safe and successful breeding season breeding season

Putting in a big effort and paying attention to detail during breeding will give your herd the best chance of achieving the desired result next spring. The breeding season is a very busy time for farmers and especially for AI technicians. Be mindful of any hazards around the handling facilities and rectify them in time. Keep facilities clean to avoid surfaces becoming slippy. A shake of sand provides instant grip. Being organised and available if possible to help your technician is appreciated as AI is a job that requires concentration and precision to achieve the best results. Be mindful of biosecurity, have a clean footbath and washing facilities available for your technician.