With good grazing conditions continuing on farms it may be time to start turning yearling heifers out to grass.
A cold front has moved in across the country in the last number of days, which has resulted in air temperatures dropping and snow arriving in some areas.
Although it has gotten much colder, ground conditions in most parts of the country are still quite good and it may be time to turn out the replacement or bulling heifers.
In the areas where the snow has cleared, if not already done, it may be time to look at getting your heifers out of the shed.
Some farmers that had already turned out their heifers, but had to temporarily rehouse them until the snow had passed, with many of these farms already getting the heifers back out.
Yearling heifers
Yearling heifers will, in the coming months, be put in-calf and this time next year will be part of the milking herd.
These heifers should have certain targets to achieve ahead of breeding, particularly around liveweight.
Failing to reach target weights may result in lower conception rates, lower production during first lactation and may make it harder for cows to get back in-calf.
Replacement heifers are most likely the best genetics on your farm that will be bred this year. These animals are the future of your herd and if they fail to go in-calf, it could result in a major financial blow to the farm.
Because of this, it is important that replacement heifers are monitored and that targets are reached ahead of the breeding season
Mature cow weight 500kg 550kg 600kg 650kg Maintenance sub-index €30 €20 €10 €0
Based on the economic breeding index (EBI) maintenance sub-index figure, a calf’s mature cow weight can be determined.
Using this figure you can determine the weight that your yearling heifers should be at breeding.
Age Percentage of final weight €30 €20 €10 €0 Six months 30% 150kg 165kg 180kg 195kg 15 months 60% 300kg 330kg 360kg 390kg 24 months 90% 450kg 495kg 540kg 585kg
Spring grass
The benefit of grazed grass compared to silage cannot be underestimated.
Early spring grass can support liveweight gains of up to 1kg/day, so underweight or lighter animals should be given priority.
Before turnout it is important that you weigh your heifers. Seperate the underweight and lighter heifers and prioritise getting these animals out to grass.
You can also supplement these underweight animal with concentrates, to help them achieve their target breeding weights.
Continue to monitor these heifers as the breeding season approaches and if possible, weigh them again prior to breeding. Determining the weight of an animal with your eyes alone is next to impossible.