Once a day: The next couple of weeks will be the busiest period of the year on dairy farms.

The traditional approach to milking cows and feeding calves twice a day is being challenged by new thinking on once-a-day milking and feeding.

New Zealand research has shown a reduction in lactation yield when cows are milked once a day in early lactation.

One study found a 7% drop in total lactation yield when all cows were milked once a day for the first three weeks of lactation.

Keep in mind that this is the first three weeks of lactation, not the first three weeks of calving.

If milking once a day for February, the effect on the herd lactation yield would be much smaller.

Some farmers are keeping the freshly calved cows in one group and milking these cows once a day.

Make sure to adhere to the withdrawal periods on the label if antibiotic dry cow tubes were used at drying off.

It is a good idea to get the first few tanks of milk tested for antibiotics. Other farmers are feeding milk to calves once a day.

If doing this, the milk used should have a high solids content and the calves should have access to meal and water at all times.

Doing things once a day is an effective way of reducing the workload.

Milk fever: With a lot of cows in very good body condition score, the risk of milk fever is greater this year. Some farmers are already experiencing problems.

Not having cows over fat is one control method but it’s too late to control that now for cows calving in the next few weeks.

There is time to prevent cows calving after St Patrick’s Day from getting too fat though.

A restricted diet of 8kg or 9kg of silage dry matter is probably sufficient for cows that are at the right body condition score now.

Feeding silage that’s high in potash is also a risk factor for milk fever.

Potash locks up magnesium and magnesium is needed for the absorption of calcium from the bone. It is a shortage of calcium that causes milk fever.

Giving cows extra magnesium before and after calving will help to prevent milk fever. Some farmers sprinkle sweetened calmag on silage, or put magnesium flakes in the water.

Cows will need up to 40g of magnesium in the diet prior to calving. Other people will give at-risk cows (older, higher yielding, more Jersey) a calcium bolus after calving.

Calves: New rules are in force regarding the movement of calves. They cannot be taken to a mart at less than 10 days of age. If they are, the mart is obliged to reject them but it will show up as a movement.

If this happens, the calf cannot be exported for 30 days, which will seriously reduce the value of the calf in the ring.

Calves can be sold farm to farm less than 10 days of age for animal welfare reasons, but if this happens more than once an animal welfare inspection will be triggered.

New changes to movement certs have also been made. It is no longer possible to print off movement certs without a destination herd number.

Friesian bull calves two to three weeks old are making between €50 and €100 a head in the marts.