Both sheep scab and lice are highly contagious and once they gain entry into a flock, can establish and spread very quickly. Dipping at this time of year is the most appropriate option to treat all external parasites in a single treatment. There are options for farmers who do not have access to dip sheep, but there are generally more complicate and require a combination of injectable and pour-on products.
Dipping requires investment in time and purchasing products and, as such, it is important to allow best practise guidelines to ensure optimum control and a good return for this investment.
• Do Not Add Colours: adding colouring agents to prepare sheep for shows or sales may seem worthwhile by completing two tasks at once, but it can be detrimental. It can cause chemicals to separate, making dipping useless in combating external parasites or worse still, it also leads to a risk of poisoning sheep.
• Reduce The Pressure On Sheep: Dip early in morning or on a cool, dry day. Allow sheep to rest pre-dipping if they have been active for a period while flocking. Ideally dip sheep when empty.
• Post-Dipping Lameness: This can occur if sheep are dipped in solution left over from previous day and has become contaminated. Sheep should only be dipped in freshly prepared solution.
• Follow Manufacturer’s Guidelines: Products vary in their control, usage guidelines and also chemical composition (organophosphate and non-organophosphate dips.)
• Correct Concentration: Each time a sheep passes through a dipping tub, it removes solution and generally walks away with two litres of solution, part of which is returned through flow back from the draining pen. It is important to note that the active ingredients adhere to wool and therefore while there is solution returning to the dip tub, it is mostly water. If the active ingredient concentration drops below a certain level, sheep won’t receive adequate treatment. It is for this reason that it is critical to monitor the number of sheep passing through and top up the tub with the recommended volume when required. Over time , the solution will become weaker, even if topping up is taking place, and at a certain stage, it is highly recommended to mix a fresh batch of dip.