Why is it important to give cows an adequate dry period?

Many spring-calving dairy farmers have – or should have – begun to dry-off cows; however, usually during this time of year some farmers are temped to milk cows on, with a common phase being: ‘But sure she is still milking well’.

However, cutting corners on the dry period can prove more costly in the long term.

Moreover, where farmers have fully-housed yields will have dropped significantly by now. If cows are only producing 10-12L/day, or less, the added work and supplementation required needs to evaluated against the potential output or return.

Risks associated with ‘milking on’

Every cow needs an adequate dry period, before she calves again and starts her next lactation.

A dry period is recommended for the following reasons:

• To allow cows to build up body condition for calving and the next lactation;
• To regenerate mammary tissue in preparation for milking again;
• To optimise the benefits of hormonal changes that occur around the time of calving.

Not only is the dry period important for the cow, it is important for the farmer too. A dry period is good for a farmer’s physical health, as well as their mental health.

It is worth remembering that continuously milked cows produce between 20% and 25% less milk in the subsequent lactation, than cows that received an adequate dry period.

A dry period of approximately 60 days is recommended for spring-calving cows. A longer dry period is required for first calvers and cows in poor condition (<2.75) to ensure that they calve at the optimal condition score for the following lactation.

Thin cows, first calvers or cows with twins – which are calving in February – should be dried off now and separated from the main herd.

Also, a shorter dry period can increase the risk of antibiotic residues in milk after calving, if sufficient attention is not given to the minimum dry period duration of the product.

Best practice when drying-off

Hygiene is critical when drying off cows; as 50% of all clinical mastitis cases – in the first 100 days of the next lactation – can be linked back to the drying-off procedure.

Having a strict drying off protocol in place is critical to avoiding any unnecessary mastitis infections in the subsequent lactation.