Pre-grazing Planning

Dairy-Beef or Autumn Born Suckler Calves

These are your first season grazers; at this stage they have no immunity to worms. It’s important that they gradually build immunity over the grazing season. Unfortunately, there is no way to measure this immunity in calves. We could go out of our way to keep them away from any worms, such as keeping them housed – however they won’t develop any immunity and may wind up suffering as second season grazers if hit with a heavy worm outbreak.

Spring born suckler calves have little grass in their diet until later in the season, so their risk of disease is much lower until around weaning.

Yearlings

These animals are not yet fully immune to parasites; they can still be at risk of poor performance when infected. By laying the groundwork for good immunity in the first season, they will cope better the older they get.

Low-Risk/ Cleaner Pasture – these should have low larvae activity

• New or reseeded pastures
• Paddocks with mixed species such as clover, kale or chicory
• Pastures that have been grazed by sheep most recently or co-grazed with sheep/cattle/horses
• A pasture where the last occupants were older cattle
• Silage aftergrass later in the season

For example, you might be able to put young calves mid-way through the grazing season onto silage aftergrass. This resets the number of larvae available on the pastures to re-infect the calves, reducing the risk of disease.

High-Risk/ Dirty Pasture – these are likely to have high larvae activity

• Pastures grazed only by young first season cattle last year or that they were the last occupants
• The Calf Paddock. Where do you turn out your calves for the first time? Likely it’s the same paddock year on year.

It’s not feasible to keep away from high-risk paddocks completely but it is useful to be aware of them.  Try not to let your young calves into these high-risk paddocks too early in the season or during a high-risk time i.e. after a spell of rain after a drought. You can rather use them for yearlings or adults who have better immunity.

For your calf paddocks, is it possible to have two fields to use as calf paddocks and rotate them each year? This will limit the exposure cycle, where this year’s crop of calves will be infected by the eggs and larvae that have survived over from last year.

It’s unlikely you will have all of the low risk/cleaner pasture options on your farm. You can still use this information to your advantage by applying other measures to monitor your animals and make sure they are not losing performance.

Faecal Egg Counts (FECs)

Monthly group sampling is a good way to monitor burden on pastures. It’s a useful factor for treatment decisions. Remember, taking only one FEC shows a snapshot of that day, the parasite situation can change quickly so try for every 4 weeks to give you a better picture of changes over time.

Consistent Weighing

By utilising the weighing scales, you can track animal performance. Parasite burden can be an underlying issue to weight loss. Consider weighing at three points of the season such as turn-out, mid-season, and housing.

Future Grass Decisions

Remember if you are considering reseeding or planting multi species swards – they are beneficial for reducing larvae on pastures.