Animal Health

Is it too hot in the ‘kitchen’?

By Rod Dyson

SUMMER IS almost here, and there will be some consistently high temperatures as well as some very hot days coming, especially in some of our warmer regions.

Unfortunately, heat and sunlight can be an enemy of many products used on farms.

One of the more interesting cases is the effect of heat and sunlight on teat disinfectants. In fact, many of our teat disinfectant products have some quite interesting storage warnings on their labels.

Most iodine- and chlorhexidine-based products (the most commonly used products in Australia) have one or both of two storage warnings, and the warnings apply to both ready-to-use products and mixing concentrate products.

The first warning is a temperature warning — most commonly to store the product ‘below 30°C (room temperature)’, although some even have a storage requirement of ‘below 25°C (airconditioning)’!

The second common warning is to store the product out of direct sunlight.

Additionally, there is often a recommendation to store the product in a well-ventilated area.

We would need to be chemical engineers to fully understand and explain the implications of these warnings on our products, but a little knowledge may help to understand the basics.

For example, the antibacterial activity of iodine-based teat disinfectant products relies on the release of ‘free’ iodine as the product evaporates and/or dries.

It doesn’t take much further thinking to see that temperature and sunlight are not ideal companions for these products.

It also helps us to understand why some of them also include a warning to keep the product sealed as well as possible and for as long as possible.

While there is no suggestion that an hour in hot sunlight will render a product useless, there is an implication that deterioration of the product will be accelerated by continued storage in adverse conditions.

Furthermore, this effect is likely to be cumulative, meaning that it is likely to be the sum of all the storage conditions prior to you actually using the product which will determine if there has been any significant deleterious effect.

For example, where, and for how long has the product been stored prior to arrival at your farm? Have they been out in the hot sun at a supplier/retailer? And if so, for how long?

Once they arrive at your farm, how long do you store them before you start using a new drum, and until you have actually finished using them?

How can we reduce this risk of deterioration?

It goes without saying that these products should be stored on the farm out of direct sunlight and in as cool a place as we can find that is still convenient.

Temperatures in most regions commonly exceed 30°C in the summer, and many of our dairy areas will have numerous days over 35°C and some above 40°C.

Leaving a bulk drum of teat disinfectant out in the sun on a farm in these conditions for a month or so is simply not ideal.

Can you avoid a north-facing location? Is there a room or sheltered part of the dairy shed accessible to the front-end loader? Could a skillion be erected over the storage site to provide shade and shelter?

We have a number of clients who are concerned about storage prior to arrival at the farm. They insist on receiving a freshly delivered drum of teat disinfectant to minimise that risk, especially where the supplier is known to store the product outdoors.

Clearly, the risk of deterioration will vary significantly from farm to farm, season to season and region to region.

The risk will be lower for larger farms that get through a drum in a short period of time, however, smaller farms using a 1000 litre bulk drum over a period of a few months will logically be at a greater risk.

Do you fall into the high risk category for one reason or another?

Perhaps now, as the summer heat starts to arrive, it is a good time to review your teat disinfectant storage, because teat disinfection is probably the single most important mastitis control procedure during milking — it deserves the best quality product you can give it.