Diet helps to lower left displaced abomasum risk

FEEDING COWS a transition diet from 2-3 weeks before calving to three days post-calving has reduced the incidence of left displaced abomasums (LDAs) from 24 last year to none this year on Malcolm Fell’s Lancs unit. It has also reduced milk fever cases.

“We have always struggled to include sufficient straw in dry cow diets. The recommendation is to include straw at 2-4kg a day, but we could hardly ever get above 0.75kg when we were feeding straw ad-lib.

“But now with a mixed ration balanced specifically for dry cows it is easier to achieve the desired intake.”

When dry cows are at grass they must be stocked tightly and allowed access to another source of forage to prepare the rumen for the milking diet, added nutritionist David Jacklin.

“But good grass silage is possibly too good for dry cows, early in the dry period a modest energy forage is adequate, such as haylage. In the last four weeks of the dry period another forage should be included in the ration, such as whole-crop or maize silage. This will bring down the potassium levels in the diet.”

However, Mr Jacklin also advised including plenty of straw in dry cow and transition cow diets to improve ration structure. “The danger is that straw is overmixed, reducing the length of fibre. But it must not be long enough for cows to pick it out from other diet constituents.”