pete isaacPete Isaac, Mole Valley Farmers

Regular weighing and taking a realistic view of what late summer grass can offer is a must at this time of year to ensure heifers remain on track to calve in at a target 24 months of age, writes Pete Isaac, Mole Valley Feed Solutions.

Grass quality can decline significantly in August, while heifers become more selective in what they graze.

This means daily liveweight gains can easily slip from a target 800-900g/day to 600-700g/day.

Over time, that drop soon adds up to an additional month to six weeks on calving age, which adds cost.

See also: How to calve heifers at 24 months for improved efficiency

For example, calving in at 26 months instead of 24 months adds £133 per animal to rearing costs.

Such changes in growth are hard to spot by eye, so it’s essential to monitor – either by weigh band, weigh scales or wither height.

It’s also worth taking fresh grass samples and measuring quantity to see what grass is delivering.

If weight gains are slipping, consider supplementing with a 16% protein, general purpose youngstock concentrate at 1-1.5kg a head a day for those approaching bulling age. Those being bulled could benefit from maybe 2.5kg a head.

It’s also important to consider the effects of declining grass quality on milking cows and particularly fresh animals.

Cows might look quite happy at grass, but they may be losing internal fat which can negatively impact fertility.

The fact many farmers have chosen to cut back on feeding and focus on getting more from forage also adds to the issue, as a lot of animals are working hard this year – especially with the challenging grazing season.

Be sure to monitor cow body condition regularly and increase feeding rates where necessary to avoid long-term fertility crashes.