25 February 2000

Turnout conception cut

TURNOUT could reduce conception rates by 20% due to high nitrogen levels in lush spring grass, according to recent Irish research.

Maurice Boland of University College Dublin told delegates at the Alltech conference that research indicated that herds experienced a drop in fertility when turned out to grass. "I believe that exposure to high nitrogen in spring grass results in ovulation of less viable eggs, leading to poorer fertility. "Our research showed a drop in pregnancy rates from 55-60% to 40% within the first month of turnout. But after about a month, cows adapt and fertility returns to normal levels."

Feeding 1-2kg of sugar beet pulp could help reduce the fertility drop, said Prof Boland. "Although we do not know precisely why beet pulp helps, it may slow nitrogen metabolism and provide more energy to the animal, assisting fertility." &#42