4 ways to plan grazing for improved udder health

As turnout approaches, many dairy farmers will be polishing plate meters, calculating covers and fixing fencing.

But managing grazing for udder health is often overlooked, leaving cows exposed to high environmental challenge.

See also: How teat health can be used to evaluate milking performance

Preparing for turnout with mastitis risk in mind can make a significant difference to udder health performance.

1. Optimise cow tracks for cow cleanliness

Track dimensions are crucial for cow flow. Aim for 4m-wide walking surfaces for a group of 200 cows, with an extra metre for every additional 100 cows.

This eliminates bunching and queueing, reducing areas of high slurry build up. In addition, wider tracks lead to dung being spread more thinly, reducing contamination of feet, legs and udders.

Surfaces must be foot friendly and easy to clean – preferably ‘self-cleaning’ with the help of the rain.

This requires either a free-draining material such as hardcore topped with fine crushed stone, or a “wipe-clean” surface such as concrete sleepers.

Cows will only use the full track width if the surface is free of painful irregularities.

For loose surfaces, it is vital to compact well to avoid erosion. For sleeper tracks, it is important to minimise stones getting dragged onto the surface – artificial turf can be very effective on top of sleepers.

The correct camber improves udder hygiene by preventing erosion and slurry pooling. For narrower tracks, a cross-fall from one side to the other may be appropriate.

Wider tracks will need convex “crowns” draining from the centre to either side. Gradients should be steep enough for drainage – at least 3%.

However, cambers greater than 6% increase erosion and lead to cows using only small parts of the track, as they dislike walking across steeper slopes.

For most tracks, aim for the most direct route to reduce cost and cow mileage. The exception to this is if the direct route is steeper than 10%. If this is the case, longer routes are advisable to reduce the slope.

Steep tracks pose a high risk for slurry contamination and splashing of the udder from cows slipping. Incorporate cross-drains or “speed bumps” into sloping sections to prevent water flowing down the track.

Tracks should extend for 15-20cm under the fence (achieved using “inverted-L” posts to position fencing wire over the track). This stops cows from walking in dirty drains and prevents verges building up that impair drainage.

Before the grazing season, trim any verge growth and clear drainage areas alongside the track.

2. Prepare gateways to stay clean all season

Fixed gateways pose a high risk for poaching and cow contamination. Avoid single entry/exit points to paddocks. Instead, use wire to allow the gateway to be moved along the fence line.

If fixed gateways are unavoidable, install “exit ramps” of hard standing to protect these high-traffic areas from poaching.

In times of high challenge, strategic use of woodchip can reduce contamination of feet and legs, reducing the environmental mastitis risk without affecting pasture in the long term.

Over time, the surface level of gateways becomes compacted, leading to water and slurry pooling. Use the winter to review gateway levels, and build up surfaces as appropriate.

3. Protect water points from poaching

Poaching around water troughs is a widespread problem, which is exaggerated on many grazing platforms by having insufficient water provision. This leads to higher cow footfall than necessary.

Aim for at least 7.5cm trough space a cow, with troughs sited apart from each other to spread cow traffic.

Avoid siting water points on cow tracks or at gateways, as this disrupts cow flow and increases soiling of these areas.

Incorporate areas of hard standing for troughs, such as concrete pads or areas of stone chippings. Woodchip can be used as a temporary measure to mitigate poaching.

For troughs on solid surfaces, ensure the surface has a gradient (preferably sloping away from pasture) to prevent pooling of water and slurry.

4. Manage pasture for hygiene

Mastitis bacteria such as Streptococcus uberis can reach problematic levels within 24 hours of cows entering clean pasture.

The duration of grazing advised varies with stocking density and weather but, if reducing bacterial challenge is a priority, avoid grazing pasture for more than two consecutive days.

Often, rotating cows to maintain pasture hygiene is seen as conflicting with hitting target residuals. However, with the right strategies, both priorities can be achieved.

Use small paddocks to allow the group to hit the target residual within the short time required to avoid bacterial build-up.

Strip-grazing, combined with back fencing, can achieve the same result in larger fields.

A key limitation of strip-grazing can be water provision, but central troughs and “wheel-spoke” strips can solve this issue.

An alternative to trying to balance hygienic grazing with complete grass utilisation is to graze youngstock after milkers.

Research shows Streptococcus uberis bacteria survive on pasture for up to three weeks after cows are removed. Therefore, it is advisable to rest ground for three weeks.

Night paddocks are popular for ease of fetching cows but, unless they are given the same rest periods as day paddocks, they can rapidly become highly contaminated.