13 February 1998

CUTTING £55m DISEASE BILL

Calf mortality is costly, with 4.5% lost before reaching a

month old, but ADAS believes those losses can

be reduced. Jessica Buss reports

Calves penned individually are fed milk in their water buckets, and keep the same bucket until weaning to reduce risks of cross infection.

LIVESTOCK producers can reduce calf mortality and disease – estimated to cost the UK cattle industry £55m/year – using sound husbandry and good feeding practices, and providing well designed, adequately ventilated and clean accommodation.

ADAS claims that of the four million calves born alive in the UK each year, about 170,000 or 4.5% die in the first month of life.

Scours are one of the biggest causes of death, according to ADAS senior livestock consultant, Elwyn Rees.

Reducing the risk of scours starts by feeding adequate colostrum, with 8 litres needed in the first 24 hours, and at least two litres within four hours, says Dr Rees.

He advises treating calves navels within 24 hours of birth with tincture of iodine or antibiotic spray to avoid navel ill which can lead to poor general health, especially when calves are born indoors.

"Then after calves are removed from their dams, check that milk substitute or milk is fed at a consistent temperature," says Dr Rees.

Andy Starbuck, herdsman at Sparsholt College, Hants, where one of 20 MAFF calf survival meetings was held by ADAS advisers – ensures milk substitute is the same temperature each day.

"The calf house has its own dedicated hot water boiler set at the feeding temperature," explains Mr Starbuck. Water temperature is also checked using a thermometer twice a week. And milk powder is weighed so feeding is consistent, whoever feeds the calves.

Dr Rees adds that temperature is less important when feeding cold milk with a range of up to 10 degrees acceptable.

Once they are more than 10 days old, Mr Starbuck only feeds milk once-a-day to the 65-70 calves a year from the 130-cow dairy herd. However, feed, water and calves are always checked again in the afternoon.

Dr Rees stresses that calves should be inspected twice-a-day for signs of ill-health, such as rough coats, tight skins or to see whether they are cold to touch.

Ideally, Dr Rees advises feeding milk twice-a-day, but he agrees that once-a-day feeding requires about 30% less labour. However, once-daily feeding is not for inexperienced calf rearers, or for farms where there have been scour problems in the past, he warns.

Care is also needed when choosing milk substitute; it should be designed for the system used and mixed according to manufacturers recommendations.

Mr Starbuck rears calves in both individual pens and groups of five, using a milk substitute designed for both once and twice-a-day feeding, although the weight of powder/litre of water differs according to the number of feeds.

Those in individual pens are fed milk in their water buckets. They keep the same bucket until weaning, reducing the risk of cross-infection. Buckets are clean-ed by rinsing and wiping dry, with detergent used once a week.

Calves reared in batches are fed their milk substitute from teats in individual stalls.

Dr Rees suggests that when calves are reared on ad lib feeding in larger groups, it pays to ensure there is one teat for every six to eight calves and that teats are at 66-70cm (26-28in) above the effective pen floor. He also advises disinfecting feeding equipment every two days. When a calf is sick, isolate it and restrict feeding, increasing feeds gradually.

Calves are offered concentrate feed after four days old and fresh straw is put in hay racks, says Mr Starbuck.

"They are bedded every day with good quality dry straw. Pens are cleaned out after each calf or batch and brushed out before applying a powdered disinfectant to avoid moisture in the environment of other calves."

Mr Starbuck aims to wean calves at six weeks old, providing they are eating 1kg of concentrate.

Pre-birth care

COW management before calving will ensure calves are born strong and healthy, according to Dr Rees.

"Cows must be fed correctly in the last three months of pregnancy when the foetus is growing most rapidly. She must be fit but not fat at calving, with a condition score of three."

Low vitamin levels can also reduce calf health and vigour, increasing the risk of scouring – one of the biggest causes of mortality, he says. Vitamins A, D and B12 are important for dry cows. And rations of straw, hay or roots can also lead to vitamin E deficiencies.

Isolate your calf replacements

WHEN buying in replacements, isolate them from your own calves for three weeks, suggests Dr Rees.

"Incoming calves can spread disease organisms to home-bred calves that have not been challenged by the same bugs or been given resistance to them through their dams colostrum.

"Bought in calves should be rested in a clean, dry, well bedded pen, and not fed within at least four hours because their ability to digest milk is impaired by stress." When possible buy from one farm to minimise stress and cross-infection of disease, he advises.

Inspect calves on arrival and reject those that have dull coats, show signs of diarrhoea, have wet or thickened navels, show discharge from the eyes, nose or mouth, or are breathing heavily. Also discuss vaccination and vitamin injections with your vet, he adds. &#42

HOUSING IS VITAL TOO

Housing must be open, airy and well ventilated with 6-10cu m (212-353cu ft) of airspace for 12-week old calves. In the UK air temperatures do not present a health risk to calves in a dry, draught-free building, but

ventilation is essential to remove stale exhaled air and water vapour from bedding and

prevent pneumonia.

Air inlets should be above calf height using space boarding and outlets provided either with an open ridge or slotted roof. When the required ventilation cannot be achieved naturally, fan

ventilation must be used, advises ADASs Elwyn Rees.

Restrict the number of calves in any airspace to 30 and

preferably group in pens of less than 12, under six months old. Batch according to weight and age. And use all-in all-out

policies for pens when possible.

ADAS senior livestock consultant Elwyn Rees (right) and Sparsholts Andy Starbuck discuss husbandry.

SCOUR-FREE CALVES

&#8226 Colostrum essential.

&#8226 Feed milk or substitute at consistent temperature.

&#8226 Housing must be well ventilated.