How to Achieve Season-Long Protection Against Worms in Cattle at Grass

It is the aim of every farmer to get uninterrupted growth in their animals, but as turnout approaches there is one factor that can stop cattle from achieving their growth rate targets – PARASITES!

Worms can be a huge economic drain when not managed correctly mainly due to the impact they can have on productivity – including a drop in weight gain, milk production and reduced carcass quality¹.

However, worms do not have to be a burden and with some careful management, protection can be offered throughout the grazing season.

There are two options to achieve season-long control:  

1. Treat cattle for gut (and lung) worms in the early grazing season to reduce pasture burden and therefore infection later.
2. Closely monitor cattle throughout the grazing season for any signs of worm burdens. This requires cattle to be weighed regularly and benchmarked against their target growth rates typically 0.7 to 0.75kg/day for young stock from grass. It also requires regular faecal egg count testing for worms.

Both options are clearly different and it is important when assessing which option is right for you to factor in the labour cost, time, stress, and practicality regularly weighing cattle at grass can have.  

The only way to have peace of mind cattle will be fully protected from worms when grazing, is to implement a worming strategy.  There are two worming options that offer immunity development and will allow uninterrupted growth through the grazing season, maximising the ability for animals to make the most from grass. They are:

For youngstock, Autoworm^® First Grazer is a pulse-release rumen bolus. It releases seven doses of oxfendazole at three-week intervals, killing all common roundworms that cattle may be carrying, including lungworm. The active ingredient has no residual action, so cattle are exposed to worm challenge during each 21-day interval between pulses, thereby stimulating an immune response, but worms are killed before they have an impact on productivity

For older cattle Autoworm Finisher offers the same benefits as Autoworm First Grazer but releases five doses at three-week intervals.

Also offering season-long protection in set stocking situations is a single treatment at turnout with CYDECTIN^® 10% LA for Cattle given as a sub-cutaneous injection in the base of the ear.

The active ingredient moxidectin is distributed through the bloodstream, so worm larvae need to penetrate the gut wall - creating trickle exposure to the pathogen and thereby stimulating an immune response - before being killed.

Specifically, with immunity to lungworm in mind, the gold standard recommendation is to vaccinate. However, unvaccinated cattle can develop natural immunity when using Autoworm or CYDECTIN 10% LA through the trickle exposure to lungworm larvae present on pasture.

Resistance is a growing issue in cattle when wormers of the same active ingredients are overused. That is why it is important to follow the Control of Worms Sustainably (COWS) best practice principles (www.cattleparasites.org.uk) for the most effective and responsible use of cattle wormers and also work with a dedicated animal health provider to draw up an effective worm control plan.

For farmers concerned not to over-use the ML wormer group - which, for use in cattle, includes ivermectin, doramectin, eprinomectin and the highly potent moxidectin, alternating use of Autoworm one year and CYDECTIN 10% LA the next is a valid strategy for season-long control.

Whatever way you decide to manage worms the most important thing is to have a worm control plan in place. Not controlling worms will only have a negative impact on herd health and efficiency and ultimately your bottom line.