Dairy heifer fertility: Mark Roach, Aldford, Chester
Mark Roach, Grosvenor Farms, Aldford, Chester
The more consistent and boring the ration at and around service, the better, says Grosvenor Farms manager Mark Roach. “Every time you alter the diet during this critical period, be it changing silage clamp or introducing a different component, there will be a knock-on effect on fertility.
“We achieve 70% conception to first service with conventional semen and 60% with sexed. But we have experienced a drop to about 45% when diets are altered.”
And with the main aim to calve most of the 1060 replacement heifers into the four Grosvenor herds, totalling 1440 cows, at 24 months of age, getting heifers in calf is critical. “By keeping heifers inside on a controlled diet, we are able to achieve growth rates of 0.8-1kg/day, with the aim to get stock to 350kg at 13 months.”
Heifers are then served in a tight window at 13-16 months. “Diets must be kept consistent in this period and six weeks after service to improve the chances of egg implantation.”
This year, heifers at this stage receive a TMR of 15-16kg dry grass silage (60% DM) a day, 4.5kg Trafford Gold and heifer minerals.
“Because our grass silage is low ME, we supplement with Trafford Gold. Getting the energy right is important as you want heifers to grow about 10% faster through the service period,” he says.