In 2020, Oceania Dairies in the South Island banned the use of abamectin based drench products in lactating dairy cows after abamectin residues were detected in UHT milk products imported into China. This ban was enforced on Oceania’s suppliers as a condition of supply.
Abamectin is commonly used in dairy cows as low-cost pour-on and these products currently have a nil milk withhold claim. These products while primarily aimed at the control of internal parasites also control lice.
MPI is now consulting on implementing a milk withhold for these products, set at 35 days. Industry expectation is that this new milk withhold will be implemented. In advance of this decision, our advice is to start removing these products from your dairy farm, there are other safer and very effective options.
The risk of retaining the supply of abamectin drenches for use in non-lactating cattle on a dairy farm, is the unintentional application onto animals in-milk. The detection of these residues in products is not the story we wish to be reading about.
So, what to use in adult dairy cattle instead of abamectins?
The first question to ask is, does your herd suffer from lice? If the answer is “no”, then we will recommend either Eprisure™ or Eprinex®.
Episure™ comes as either a pour-on or as a low-dose injection (5 mL for a 500 kg cow) applied subcutaneously under the skin. The low-dose injection will provide a higher and longer level of the eprinomectin active in the blood plasma. Eprinex® comes as a pour-on only.
If you are injecting all cattle with Multmin® three to four weeks prior to calving as an aid to reducing sub-clinical and clinical mastitis, either EpriSure™ or Eprinex® can be applied at the same time.
Both Episure™ and Eprinex® have a label claim for the control of lice but if you have a lice problem, these are not the preferred products you should be reaching for.
For lice control, use a specific lice product. Options available include Pouracide NF which comes with a six-week claim for both biting and sucking lice. This length of control is important as it allows time for the lice eggs to hatch; this occurs around 10 days after the eggs are laid. The other advantage of Pouracide use in dairy herds is the nil-milk withhold. The meat withhold is seven days.
Other pour-on options include Lypor® (milk withhold 14 days and meat 10 days), Coopers Blaze® (nil milk withhold and 28 days for meat), and Delmax (nil milk, 28-day meat and nil Bobby Calf withhold).
There is much to think about when using these products so either speak with one of our vets or to one of our commercial managers to get clarity on the right approach.