Its vitally important to prioritise the next generation of milking cows by focusing on achieving replacement heifer target weights over the next number of months.
Hitting target weights at certain milestones is crucial to ensure replacement heifers are on course to achieve the main goal of being 60% of their mature weight when bred at 15 months.
Meal feeding at grass
Transitioning calves from a milk-based diet to a grass-based diet can be tricky. Spring born calves that are weaned and now at grass, should be offered supplementary concentrates in the diet for 4-6 weeks minimum, to ease with the transition onto a grass-based diet.
Where 102kgs concentrate is offered at grass for the first number of weeks, this reduces the total amount of fresh grazed grass in the diet and avoids hungry calves over-indulging on lush low fibre, high N grass; resulting in what is often referred to as ‘summer scour’.
Alongside offering concentrates, fibre sources can also be offered in the diet (e.g., straw/hay/roughage) through this transition, as well as turning calves into slightly heavier covers. We must remember young calves are not fully developed ruminants yet and high quality lush grass may not be the best forage for supporting rumen development.
Target weights
Weighing scales are by far one of the most under-utilised management tools on farm. Timing of weighing can also be beneficial. By weighing in the weeks pre-housing, compared to weighing at the point of housing, allows farmers to identify heifers that are behind target. The best advice is to group accordingly and make alternative plans for those heifers under target weights.
The threshold figure for 2023 spring born weanling heifers is approximately 200kg in mid-September (33% of an assumed mature weight of 600kg). Heifers that are lighter than this should be separated and given priority access to the highest quality grass and re-introduce concentrates depending on their weight relative to the herds target.
Further information:
For more information, contact your local Sales Advisor.