The Parasight

Welcome to this month's edition of The Parasight. We’re taking parasite-threat updates to the next level with our collaboration with post-mortem vet Ben Strugnell BVM&S Cert PM MRCVS from Farm Post Mortems, who will share with us timely, on-the-ground footage.

Understanding what’s actually happening in flocks around the UK will give you more insights on what you should be looking out for with your own animals.

Coccidiosis, Nematodirus & Haemonchus - May 2025

Description: this month, Ben first covers why lambs are dying from starvation and chilling. He then goes on to explain the current situation with coccidiosis and nematodirus in lambs, including when to watch out for them. Finally, Ben discusses a 200-ewe flock diagnosed with haemonchosis, highlighting how this parasite might be adapting to become more cold-tolerant and pose an early-season threat the following year.

Missed a previous episode of The Parasight?

Catch up on Ben's insights of timely parasite threats with these past episodes of The Parasight:

: Description: This month, Ben shares two cases. In the first, bought-in hoggs were found to have resistant worms, highlighting the importance of using a quarantine dose such as the group 4 wormer Zolvix™. In the second case, Haemonchus was found, indicating that worms had overwintered in the hogg’s abomasum. Finally, Ben warns that as spring has arrived, it’s worth thinking about which parasites are on the move and how to prevent them.
: Description: This month, Ben discusses the unpredictability of liver fluke this season, which is influenced by the mild winter and wet conditions. He explains the importance of identifying the stage of fluke you’re targeting to select the correct treatment, as well as the diagnostics needed for accurate treatment. Ben also shares a few fluke cases, including one where housed tups were treated with triclabendazole, but resistance was suspected after continued condition loss and a death. He then explains what could have been done differently, including the tests available. Ben also describes how liver fluke in cattle can act as a reservoir. Finally, Ben touches on infectious abortion in sheep and emphasises the importance of analysing silage for pregnant suckler cows to ensure optimum cow health.
: Description: Ben discusses three cases of liver fluke in ewes, including triclabendazole resistance, highlighting the importance of knowing the fluke’s life stage for effective treatment. He stresses the need to use the right actives at the right time for effective liver fluke control to optimise sheep health. He also emphasises the value of analysing silage for energy, and the various benefits this can provide for your flock.
: Description: Ben discusses a case where poor-looking hogs were treated with triclabendazole under the assumption they had fluke. However, after a post-mortem examination, worms and a selenium deficiency were found. He then goes on to describe what the farmer could have done differently to prevent any damage to sheep health, including the various diagnostic and treatment options.
: Description: This month, Ben explains the various reasons why your tail-end store lambs may be struggling to finish. He then describes the different diagnostic options available to identify these issues, helping you plan ahead and prevent them from occurring in the future. Additionally, Ben highlights how you can prepare ewes for lambing, emphasising the importance of analysing silage to ensure ewes receive sufficient protein and energy during this critical period where nutritional problems arise. He then explains why these nutritional needs are vital for their health.
: Description: Despite the sudden drop in temperature, Ben explains that he is still observing random cases of liver fluke in sheep. He emphasises the importance of continuing blood monitoring in lambs to help determine the optimal time to treat them, as failing to do so could have serious consequences for sheep health. Ben also notes that the cold weather has slowed the reinfection rate for worms following treatment. Additionally, Ben discusses the impact of cattle parasites, such as lungworm in calves around housing time. He highlights key timings for lungworm treatment and stresses the importance of avoiding sudden changes in diet, as well as maintaining good ventilation for calf and cow health during the housing period.
: Description: This month, Ben emphasises the need to plan properly for weaning time, ensuring lambs have the best chance to survive. He explains how the shifting temperatures have led to a rise in Pasteurella in lambs, often with a selenium deficiency, and describes which lambs are most vulnerable to this disease. Ben also discusses how poorer ewes are at risk during the weaning period due to the volatile weather conditions. He warns about the issues related to creep feeding lambs and the impacts this can have on their health. Furthermore, Ben describes the problems associated with low magnesium levels in cattle and the increased demand from their calves. Finally, Ben provides an update on lungworm and liver fluke.
: Description: In this shortened edition of the Parasight, we are joined by Cammy Wilson from The Sheep Game. This month, Ben explains how to diagnose lungworm in cattle, and the negative impacts of Haemonchus, liver fluke, and other worm species on sheep health.
: Description: This month, Ben has seen an early rise in lungworm and haemonchus and explains the consequences of these diseases on cattle and sheep health. He speaks on the importance of targeting treatments for farm animals, monitoring with faecal samples, looking for the early signs of resistance, and the watch outs when turning farm animals out for the first time. Also, Ben covers the elements to capitalise on with weaning time approaching.
: Description: This month, Ben’s focus is on sheep diseases. He covers pasteurellosis in lambs and its negative impacts, the most appropriate times to vaccinate, and worms such as nematodirus. Ben also explains how to check if your worming treatments are effective, emphasising the importance of timing your faecal samples correctly. Also, there was a discussion around the importance of accurately weighing, and calibrating equipment properly to avoid underdosing.
: Description: Ben discusses the increased risk of mismothering/starvation/hypothermia complex for lambs and how they have contributed to high mortality rates. He looks at the main disease risks of nematodirus and coccidiosis in lambs, explaining how to distinguish between both, and highlights the importance of developing immunity. He explains the continued impact of poorer quality forage on suckler calves and cow health such as abortions and cattle diseases like listeriosis. Also, Ben covers the importance of hygiene, navel dressing and colostrum for newborn calves.