Having heifers at the right weight for breeding and calving results in much improved fertility and milk solids performance in first and second lactation.

In many herds, heifers can tend to fall off target weight in autumn of the first grazing season and through the first winter; poor daily gains caused by poor grass intake/silage quality are common.

Check your calf weights this month to track progress; the targets set out differ by maintenance sub-index, which is available on your Economic Breeding Index (EBI) report (Table 1). Ask your advisor if you are unsure or use the national average figure as a starting point if your herd is Holstein/Friesian type.

Ensure that the heifer calves receive a fresh break of quality grass at least every three days in the autumn. For heifers that are underweight for age/index, separate for extra concentrate feeding until housing. Test silage and reserve the equivalent of three bales of high-quality silage (>74 DMD) per heifer. These are priority stock for the winter.

Table 1: Target weights (kg) for February-born dairy heifers

The above article was prepared by Dr. Joe Patton, Head of Dairy Knowledge Transfer and first appeared in the Teagasc Dairy Advisory Newsletter (PDF).