The method used to dry-off cows can significantly influence how many udder infections establish during the dry period. The aim is to shut down milk secretion and seal the teat canal as rapidly as possible – this usually takes about two weeks. Most new infections occur in quarters where the teat canal has not sealed.

The Countdown Downunder Farm Guidelines for Mastitis Control (Guideline No. 16) gives practical recommendations for successfully drying off milking cows with the minimum risk of infection. These recommendations are summarised below.
 

1. Dry-off cows as soon as their production reaches 5 litres or less per day.

A cow producing less than 7 litres/day is trying to dry herself off. Continued milking of these cows prevents teat plug formation and makes them more prone to new quarter infections. Cows producing less than 5 litres/day may significantly increase bulk milk cell counts (BMCC), even when they do not have mastitis, due to cells concentrating in the reduced volume of milk.
 

2. Cease milking cows producing 12 L or less per day at drying-off
 

3. Take steps for cows producing more than 12 L to reduce production to 12 L or less by the drying-off date. These steps involve reducing food intake and changing routine

Farmers should plan for drying-off – generally allow at least one week’s lead-time before the drying-off date.

Cows that are still producing more than 12 L of milk near drying-off time require special management if they are to spend 6-8 weeks dry and attain their production potential in the following lactation. Countdown recommends the following procedure to reduce yields for drying off –
 

One week prior to the final milking
• Take high-producing cows off concentrate feed

Three days prior to the final milking
• Move to a paddock with very little feed
• Reduce feed intake to maintenance level (about 7-8 kg of hay for a 500 kg cow)
• Separate the cows from the main herd if practical
• Change the routine of milking for cows to be dried off – eg. graze in different mobs, and bring to the dairy via an alternative route if possible.
 

Remember that animal welfare codes require water to be always available.

4. Dry-off abruptly; do not skip days and preferably do not skip milkings.

Cows should be milked as usual at each milking until drying-off (do not deliberately leave milk in the udder). Intermittent milking provides a stimulus to produce milk and impedes sealing of the teat canal. The risk of mastitis is greatly increased if cows are milked every second day.
 

5. Don’t leave cows in laneways or yards immediately after drying-off.

6. Put the cows in a dry, clean paddock (not heavily soiled with manure, no bare ground, no exposure to dairy effluent) for 3-4 days after drying-off.

 
It is important to minimise the number of bacteria on teats by teat dipping after the last milking and not allowing cows to lie down on bare ground or areas that are soiled with manure in the two hours immediately after Dry Cow Treatment is given. Cows are particularly susceptible to infection until the keratin plug forms.


7. Continue the ‘maintenance only’ diet for another 3-4 days for cows that were producing 12 or more litres/day in the week before drying-off.

Milk leaking from the udder, particularly under pressure, will impede the development of the keratin plug and increase the chances of infection. It is often useful if recently dried off cows are kept in a paddock well away from the milking herd and milking area to reduce the possibility of triggering milk ejection.

 

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