THE risk of environmental mastitis and lameness is increased when cows linger in wet, muddy areas.
Congregation and dunging of cattle at watering points can increase exposure to environmental bacteria as well as reducing the health of the teat skin.
Adequate drainage and good tracks and lanes reduce problems associated with dirty teats and udders.
Cow tracks should be correctly formed with a good sub-base (grass and topsoil removed) and compacted before and after the gravel surface is laid.
Gravel needs to be selected carefully (trial a small load first) so that tracks are comfortable for cows to walk on and do not contribute to lameness.
The wearing course should be crowned to shed water and drains, and drains should be provided at the sides to direct water away from the general track area.
Fencing should be arranged so cows remain on the track and do not have access to drains.
Avoid development on steep slopes.
Roads should follow contours and the landscape and should be graded with a sloping surface in order to promote infiltration (into surrounding pasture).
Tracks should be wide enough for ease of stock and vehicle movement and access to gateways.
It is suggested that they be up to 8-10m in width for large herds. Widen tracks as they near a shed or at sharp bends, as stock tend to concentrate, slow down and cause damage in these areas.
Water should not be allowed to run down long sections of table drains as the volume and speed of run-off water can erode the drain and track – taking large quantities of soil into drains and streams.
Culverts should be placed at intervals to cut water off and then send it across the slope into dense pasture.
The steeper the track the closer the culverts need to be. Hay bales and similar material can help slow water down on tracks.
Place electric wires to keep stock on the crowned part of the track and out of the drains. This avoids pugging of the track edges and stock foot problems.
Wires should also be placed to allow easy grading of the track surface.
Do not plant trees where they will shade the track. It will not dry out as quickly and tend to cut/pug up.
Tracks on ridges will require less drainage and maintenance than those going across a hillside.
The steeper the slope of the track, the more maintenance will be required.
Jakob Malmo from the Maffra Veterinary Centre said most farmers are aware of the need to shape or crown farm tracks.
“More effective and longer lasting results could be achieved if farmers would use a grader rather than just a back blade behind the farm tractor to form the necessary shape of the track.
“Adequate compaction using purpose-made compaction equipment which is appropriate for the material being used is essential.
“It is not sufficient to run a truck or tractor over the newly metalled areas to compact them.
“Neither truck nor tractors are capable of providing sufficient compactive effort and there is usually an area which cannot be rolled anyway due to wheel spacings.”
Jakob said drainage is another area requiring attention.
“The function of drainage is to provide somewhere for surface run-off to flow into and to prevent moisture seeping into the base of the track, thereby softening it.
“It is equally important that the water, once in the drain, has somewhere to flow to.
“Attention to detail with the drainage system is one of the most critical factors in determining the overall performance of races, particularly if everything else has been done right.
“It is recognised that constructing farm tracks can be a relatively expensive procedure. In many cases is not possible to upgrade all sections of the farm track at a one-time, and in many cases this is not necessary.
“Attention should be given to any broken sections of track, sections of track which cause a slowdown in cow movement and sections of track subject to the heaviest amount of traffic – for example, tracks approaching the milking area.”