22 October 1999

Stop lameness at calving time

Recent research shows

cows are more susceptible

to lameness around calving.

But will recommendations

based on trials work in

practice? Marianne Curtis

took Bristol vet school

scientist, John Webster to

one Glos unit to find out

CALVING weakens cows feet, according to latest research from Bristol vet school. But comfortable cubicles and dry pre-calving diets mean lameness is well under control, at less than 5%, on one Glos dairy unit.

Recent MDC funded research, conducted by John Webster at Bristol vet school, concludes that lameness around calving is not nutritionally related. Producers and some vets are mistaken in believing that lameness occurring around this time is a mild form of laminitis, caused by feeding high starch diets, he says.

"Lameness around calving is often attributed to sub-clinical laminitis, even by vets. However, most is not nutritionally related. Changes in cows around calving – possibly hormonal – weaken tendons in the foot, rather like a sports injury. Therefore, it is best to minimise risk of injury to feet at this time."

Housing animals in straw yards four weeks before and eight weeks after calving, when feet are most vulnerable, is ideal for reducing foot injuries, advises Prof Webster. But high cell counts and mastitis problems in Nick Spencers 130-cow herd meant a move from straw yards back to cubicles.

Three years ago, when cows at Middle Hall Farm, Eastington, Glos, were housed in old cubicles with broken concrete, lameness affected 30-40% of the herd.

Disillusioned with cubicles, Mr Spencer moved cows onto new straw yards for two years and lameness almost disappeared. However, despite bedding twice a day and cleaning out yards every three weeks, cell counts in the 9500-litre herd exceeded 200 and there were 15 cases a year of mastitis.

"High cell counts and mastitis were costing far more than lameness, so we installed cubicles. Cell counts fell to below 130," says Mr Spencer. Lameness has also remained low due to good cubicle design and stockmanship, according to Prof Webster.

"Achieving a balance between foot health and udder health is a dilemma. Cubicles on this unit are big enough for cows, encouraging them to lie down which takes the weight off their feet.

"Although some may say the cubicle heel height of 8in is too high, there is no evidence that it contributes to lameness and it helps keep cubicles clean and dry."

Heifers on the unit are trained to cubicles from six-months-old which helps in the fight against lameness explains Prof Webster. "Where heifers have not been trained they tend to stand a lot, putting extra strain on feet."

Separating heifers also helps reduce standing time because they dont have to compete with cows for feeding and milking, explains Prof Webster. Although Mr Spencer agrees, the extra work created by having to milk an additional batch of animals means it is difficult to achieve in practice, he says.

Research at Bristol vet school has also shown that feeding high dry matter diets before calving can reduce foot lesions by up to 50%. "Drier diets mean cows produce slurry with a different composition which causes less heel erosion than wetter diets. Deep heels are essential for adequate shock absorption," adds Prof Webster.

Mr Spencers dry cow ration is ideal at 44.5% dry matter (see table), and contains 4kg of wheat straw which helps stimulate rumen function in preparation for lactation, says Prof Webster. Producers with wet silage at only 20% dry matter should consider wilting silage for longer to raise diet dry matter, he adds.

Middle Hall dry cow ration.

Fresh weight (kg)

Grass silage 16

Wheat straw 4

Premix * 4

Minerals 0.5

* Premix contains rape, soya, wheat distillers grains, maize meal, fishmeal, minerals.

REDUCING CALVING LAMENESS

&#8226 Minimise foot injuries.

&#8226 Consider straw yards.

&#8226 Separate heifers.

&#8226 High dry matter diets.

REDUCE CALVING LAMENESS

&#8226 Minimise foot injuries.

&#8226 Consider straw yards.

&#8226 Separate heifers.

&#8226 High dry matter diets.