Farmer Focus: Shift in pregnancy diagnosis timing pays off
Ewan McCracken © Steffan Hill I would like to hope that by the time you are reading this article, we will have reached the final stages of the breeding period.
Having started just under 12 weeks ago, 70% of the milking herd has had successful pregnancy diagnoses already.
One factor that has played a positive role in increasing this value has been pregnancy diagnosing (PD’ing) cows regularly and early, from four weeks after the mating start date.
See also:Â What is the secret to a smooth calving period?
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Until a couple of years ago, we would have done this in late summer after breeding was finished, hoping for a low empty rate.
Starting at an earlier stage has allowed us to identify “phantom pregnancies” – cows that appear to be in-calf, as they haven’t shown a heat three weeks later, yet when PD’d turn out not to be.
This effectively rules out a chance to service them on their second cycle.
Having identified these problem cows, re-cycling programmes have been administered to bring them back into their natural cycles.
As expensive as it might seem, this method is far more financially viable than to miss another potential cycle.
Financial reviews carried out by George Ramsbottom from Teagasc Ireland found that each day of slippage in calving date reduces net profit by £3.96 a cow a day through loss of production and increased culling rates in a block-calving system.
By ensuring that cows have as little physical and metabolic stress as possible throughout the breeding season, we can ensure that what limits cows’ fertility is only what we can’t control.
We can minimise metabolic stresses by feeding the cows high-quality grass swards (with a bit of clover thrown in for good measure).
And one way we’ve reduced physical stress is by using a Batt Latch.
This mechanism automatically opens the field gate at a set time twice a day, reducing the cost of fuel, labour and lameness.
With our furthest walkable field nearly 3km from the farmyard (with no road crossings), allowing the cows to walk home from the field at their own pace has been crucial to reducing physical stress.
For our farm, the Batt Latch can save up to two hours a day, which equates to about 500 hours a year on our 250-day grazing cycle, freeing us to use time in other ways – or even just get an extra hour of sleep at night.