Picking a good team of sires should be the number one task at hand for winter milking farms right now, as breeding is set to kick off within the next few weeks.

Based on the average gestation length of 285 days, liquid milk suppliers will ideally be wanting a mating start date of December 20 to calve down early next October and make the most out of their contract.

However, this is not a task that should be taken lightly, as the genetics of the sires you choose will stay in the herd for years to come.

Therefore, sitting down and taking the time to choose a bull team based on what you need to maintain and improve in your herd to strive for genetic gain is a must this week if you have not already done so.

Liquid milk suppliers will also need to determine how many cows are actually needed to fulfil their contract, as having extra cows calving at that time of year is difficult to make pay.

EBI

Most farmers will have their bulls already selected, but many still have it on the long finger, especially with confusion around the base change to the economic breeding index (EBI).

However, this should be no reason to worry about picking a bull team, as the bulls and your cows are exactly the same as before the update, just with changes to their base value.

The biggest worry for farmers is the change has resulted in some traits having negative figures.

For example, previously picking a bull with a negative milk yield would have been seen as a ludicrous move by winter milkers.

However, if the base change has resulted in a cow having a milk yield estimate of -50kg, choosing a bull with a milk yield of -25kg is still a good option, as you are actually gaining 25kg.

The same goes for all milk sub-indexes.

It is still worth noting that the greater the difference from your herd's values, the more rapid the genetic gain.

Speaking at the Teagasc National Dairy Conference recently, Teagasc's Dr. Donagh Berry said the actual performance of the base cow is not relevant when choosing bulls.

Instead farmers should know the mean genetic merit of the herd relative to the actual performance of the herd before selecting sires.

Breeding

Once farmers have gotten their heads wrapped around the new base changes they can begin picking their bull team.

When selecting these bulls you should ideally refer to a breeding adviser and have each and every cow analysed using the likes of SireAdvice to ensure you are confident with your selection.

Tools like this allow you to view the data from previous lactations and compare the cow's actual performance with her genetic performance.

This will allow you to determine what traits needs to improved on as well as helping to identify the lower performing cows in the herd and either mark them for culling or breed them to high Dairy Beef Index (DBI) bulls.

Farmers should try to avoid breeding their replacements from cows with low milk solids, poor temperament, poor fertility, high somatic cell count (SCC), or have lameness issues.

Extreme cows with regards to type/conformation should be avoided as ideally, you want to breed a robust, functional cow that will last in the herd.

You should then be ready to select your bull team, and begin considering a synchronisation programme for the start of their breeding season.

The target should be to breed all your replacements heifers in the first 10 days of the breeding season.