Calving in Dairy herds

It’s well worth reviewing the basics of calf rearing on your farm before the new arrivals make an appearance. Vet gives some pointers.

Many of our clients are now stocking up for a busy spring for calving. It’s well worth reviewing the basics of calf-rearing on your farm before the new arrivals make an appearance. I recently visited a dairy client who will focus on reducing calf mortality as one of his Knowledge Transfer targets.

He has already installed a single-unit milking machine in the calving area. He bottle feeds every calf shortly after being born and is amazed at the volume they consume.

Our conversation highlighted how a focus on colostrum management at farm level is pivotal to the rearing of healthy calves and will have far-reaching benefits in terms of protecting calves from disease and therefore maximising their future productivity and profitability.

With the current desire to reduce antibiotic usage, it makes sense to maximise the calf’s immunity with the natural protection available in the dam’s colostrum.


Although your calves may receive colostrum, the quality of the colostrum received cannot be accurately assessed by looking at milk or by knowing the parity of the cow. An easy and affordable method of testing colostrum quality on the farm is a simple hand-held device called a Brix refractometer (available from your vet). If colostrum is <50 mg/mL IgG, then it should be avoided and good-quality frozen colostrum fed instead. Remember, your colostrum can be contaminated by bacteria during collection, storage or feeding using unclean buckets or tanks – good hygiene practises are key. Quality is affected by age, diet and particularly vaccination status of the cow.


The timing of the first feed of colostrum is crucial to the newborn calf achieving passive immunity from the dam. The calf’s intestine will only absorb antibodies from the colostrum in the first 24 hours. Aim to feed colostrum as soon as possible after birth when the suck reflex is strongest; the calf’s ability to absorb antibodies is halved within six hours.


The 1-2-3 rule of thumb is a good guideline. Feed minimum three litres of colostrum (or 8.5% of bodyweight) within two hours from the dam’s first milking. Failure of the calf to absorb sufficient amounts of antibodies (IgG) from the colostrum is called failure of passive transfer. Calves can be blood tested for IgG levels if poor colostrum transfer is suspected in the herd. Less than 5.5G/dl indicates successful transfer of antibodies.

If you have the knowledge, you can plan ahead. Colostrum management is the single-most important factor in giving your calves a great start to life.