DairyCo

Field Conditions - Managing these areas

Environmental mastitis has traditionally been seen as a problem that occurs during housing. Many dairy farms look upon turning out time as an opportunity to ease their vigilance on the threats from Streptococcus uberis and other environmental mastitis pathogens.

Unfortunately, in recent times, environmental mastitis appears to be an increasing problem on many dairy farms, and rising cell counts are often a particular problem throughout the summer, due to a variety of factors. Where grazing is not adequately rotated, a build-up of pathogens can occur in the environment; the areas where cows tend to gather, where they lie during the night and high traffic areas being particularly prone to contamination.

Giving some thought to managing these areas, particularly when dividing fields into grazing paddocks is an important means of controlling the spread of environmentally-caused mastitis while at pasture. This is even more important with the wetter summers we have been experiencing and where extended grazing techniques are practiced. Some general advice on how to manage these problem areas includes:

• Observing the areas where cows regularly like to lie. These can easily become contaminated with mastitis-causing pathogens, and are likely to include shaded areas on hot summer days, flatter areas in undulating fields and areas just inside gateways. They can be managed by the use of electric fencing, moving water troughs away from gateways and careful track and gateway placement to avoid wet or poached areas that could lead to cows' udders being splashed.
• Carefully managing stocking rates in individual fields or grazing paddocks, and rotating grazing to avoid the build-up of bacteria. For example, no longer than two continuous weeks on a grazing or loafing area is recommended, followed by a four week rest, at a maximum stocking rate of100 cows/acre.
• Limiting any access to cubicle housing where access is required to buildings for water troughs, for milking or for feeding, by either roping-off cubicles or by managing cubicle housing as it would be during the housing period. If cows are buffer fed, it should be done before milking, so that cows are more likely to graze directly after milking, giving the teat sphincter time to close before they lie down.
• Wherever possible, rotating gateway use if a field has more than one possible entry/exit point, and designing farm tracks to make use of all gateway options.
• Paying particular attention to dry cows and cows near to calving in calving paddocks, as many environmental mastitis infections occur during the dry period.