The colostrum intake of many new born calves is dangerously hit-and-miss, according to Carlisle-based Paragon Vet Group vet Victor Oudhuis.
He says farmers must take account of the variability in colostrum quality between individual cows and cannot assume a calf has received sufficient colostrum just because it is left with the cow for four days.
“It’s a case of some calves getting enough and some not.
Those that don’t are more at risk from infection and it’s often calves that are left with cows that suffer the lowest colostrum intake.”
A farmer needs to know exactly how much a calf has had, he says.
“This means four litres of good colostrum.
Six pints in six hours is the broad rule and seems to suffice on most farms.
For a calf suckling a cow that means 20 minutes of vigorous suckling.”
The highest level of absorption is within the first six to eight hours.
There’s little or no absorption after 24-36 hours when the calf’s gut is closed, adds Mr Oudhuis.
“When the correct amount of colostrum isn’t taken during that relatively short period of time, the calf will be left with a low level of immunity until it builds up its own protection.”
Mr Oudhuis says calves need 200-300g of immunoglobulins – good colostrum should contain 70g in each litre, so three litres is required.
And he feels not enough consideration is given to the wide variation in colostrum quality from cow to cow.
“Some cow colostrum may contain as little as 30g of immunoglobulin per litre and heifer colostrum contains half the level of antibodies compared with that of a cow.”
Calves from heifers should be supplemented with colostrum from other cows to make-up for the shortfall.
It’s also vital that calves from heifers consume three litres of colostrum in the first six-eight hours after birth.
“Colostrum meters are more widely used in the USA, but they ensure a cow is producing the correct density of colostrum required to provide adequate immunity.”
Extended feeding of colostrum is also a way of improving colostrum management and can help protect against localised enteritis.
“For farmers who want to adopt this method I would suggest feeding colostrum for up to two weeks to supply the calf with a continuous, localised immunity.”
Farmers should only collect the first milk and either store it in a fridge for up to a week or leave in a sealed container at room temperature to allow it to acidify.
“Although it has a distinct smell it’s still effective and should be used at the rate of 0.5-1 litres a day by thoroughly stirring it into the calf’s normal milk.”
It works by becoming attached to the gut wall, providing a teflon-like protection.
“This prevents bacteria and viruses latching to the gut.”
But he warns this isn’t the same as leaving a calf on the cow for four days.
“Antibody levels in cows’ milk drops sharply after calving and by day four there are hardly any antibodies present,” he explains.
Vaccinating cows one month before calving to boost the quality of the colostrum, particularly where a rota corona or E-coli problem has been identified should also be considered.
“At a cost of about £8 vaccination is worthwhile, but calves must still receive the correct intake of colostrum for vaccination to be effective.”
Although colostrum will protect against pneumonia, navel ill, joint ill and septicaemia, a local immunity is needed for calf scours.
“The day before a calf starts scouring their muck carries a high level of antibodies which have diffused into the gut to cope with the problem.
“Farmers often cannot understand why a calf is scouring when they’ve made sure it’s received correct levels of colostrum, but it doesn’t work like that.
When I spot calves on a farm with joint ill, septicaemia and navel ill I know colostrum management is poor.
But when calves are scouring with enteritis it’s more likely to be a hygiene problem.”
Once an outbreak of scouring occurs in a calf house the best advice is to contain it by setting up calf pens in a clean building away from the one holding affected calves, he reckons.
“And when calves are scouring don’t forget to start calving in a new, clean pen because that’s where the infection is being picked up. Hygiene in the calf house and the calving pen go together.
They must be dealt with as one source of infection.
“The calving pen can be a hot-bed of germs.
As soon as the calf hits the floor it’s at risk.
There’s an assumption that provided the calf is standing and sucking it’s fine, even when it’s showing slight scouring.
But even that is enough to start off a build-up of infection on a straw bed so it really is important to be strict about hygiene in the calving pen,” stresses Mr Oudhuis.
He advises farmers who are in doubt about colostrum management to ask their vet to take blood samples from new born calves – less than a week old – and to have a zinc sulphate turbidity test to measure the amount of antibodies present in the blood.
“But good hygiene goes hand in hand with colostrum management.
Disinfection doesn’t have to be expensive.
Sodium hypo chlorite and even household bleach can be effective against E-coli, rotavirus and coronavirus,” he adds.