Loose yard management to control environmental mastitis in dairy cows

The risk of mastitis infections from the environment in lactation is higher in loose yards than when cows are housed in cubicles. To control environmental sources of mastitis, it is important to maintain low levels of bacteria near the teats and teat ends.

Well-managed loose yards can reduce the risk of picking up infections from the environment in lactation. To minimise the risk of mastitis infections, aim to:

• Keep the cows clean and as free from manure soiling as possible
• Minimise the risk of teat and udder injury

Straw, woodchip, and sand are the main materials used for bedding in loose yard systems. The base of the loose yard should have excellent drainage, possibly with sand on top of hardcore or concrete.

For loose-housed systems, priority should generally be given to the space allowances for high-yielding cows, and bedding frequency should be increased if limited space is available.

Our information on bedding management to reduce the risk of environmental mastitis will provide further detail.

Managing milking cows in straw yard systems is difficult and, in general, mastitis rates are higher than in cows housed in cubicles. High-yielding cows consume more food and, therefore, produce greater quantities of dung and urine, leading to rapid build-up of contamination. A 700 kg cow produces over 60 litres of slurry per day, most of which will end up in the bedding and in passageways.

A knee test with clean overalls or kitchen paper can immediately make clear whether a bed is comfortable and dry enough for the cow. Kneel in the stall for 10–30 seconds with clean overalls or kitchen paper. If your knees are wet, the bedding is not dry enough.

An 8,000-litre cow needs approximately 10 m², while a 10,000-litre cow needs 12.5 m². If limited space is available, priority must be given to the space allowances for high-yielding cows. This could be done, for example, by regrouping the lactating cows and/or higher stocking of lower-yielding cows in favour of transition cows, and cows in early lactation.

Managing milking cows on sand yards can be labour-intensive but, in general, mastitis rates are lower in cows kept on sand yards than on straw yards, and bedding purchase costs may be lower.

It is important to note:

• There should be a bedded lying area of 1.25 m² per 1,000 litres of milk per cow (herd annual milk yield)
• New clean, dry straw must be put in yards at least once daily, and twice daily should be considered if mastitis problems persist – bedding should be spread evenly
• To bed lactating cows, aim for at least 15 kg of straw per milking cow per day
• Straw yards should be cleaned out completely at least once a month
• All alleyways, loafing and feeding areas MUST be scraped out at least twice daily
• Dung must be removed at least twice daily from lying areas
• Fresh, clean sand should be spread evenly in the lying areas at least daily
• Sand yards should be cleaned out completely at least every 6 months or earlier, if necessary

If you would like a hard copy of the Control of environmental mastitis guide please contact publications@ahdb.org.uk or call 0247 799 0069.