Worms – the old problem?

By 24th August 2015News.

Return of an old problem – Worms!

Parasitic worms are an old problem that is often overlooked. Traditionally we would worm the sow herd twice a year, in feed, with May and November the favoured months, when compounders would try to collate all farmers to worm at the same time. This had the benefit of reminding us that it needed to be done, and when this system was in place we rarely found any evidence of worm infection in sows.

The traditional bi-annual worming generally continues in outdoor sows, however indoors sows are rarely wormed regularly.


To look for parasitic worm infection we collect sow faeces and use a McMaster flotation method to separate and count the eggs from each sample. In the last four months we have been getting record breaking counts.

A second opinion investigation of a farm with nine months of very poor farrowing rate (70%) gave us the highest reading to date – over 20,000 eggs per gram of faeces! Clinical examination and record investigations showed considerable weight loss in the farrowing house on this farm. High levels of worm infestation result in energy and protein loss from the sows, this will particularly occur in the farrowing rooms when sows are under most pressure. The end result is loss of body condition which will reduce the number and quality of eggs the sow ovulates, affecting litter quality, litter size and farrowing rate. A 20% reduction in farrowing rate for a nine month period is a terrifying loss of piglets, particularly in the challenging economic time that we are currently in for the industry!

“What would I see if we had a worm problem?”

The common gut worms we see in continuous, solid floored, grouped sow housing are strongyle worms. These can either be a nodular worm in the large intestine, or a red stomach worm. The main clinical sign is loss of condition, despite adequate eating, and you might also see loose faeces.

“Where are the worms?”

Sows ingest eggs from flooring contaminated with infected faeces, after less than five weeks the eggs will have hatched in the sow, become adults, and started producing eggs themselves, continuing the cycle of infection.

“So what do we do about worms?”

  • Whole Herd Treatment: Treat sows and boars in feed every six months, as previously suggested, in May and November. You must consider withdrawal times on culls.


  • Farrowing House Treatment: Worm sows by injection on entry into the farrowing house with an ‘ivermectin’ based product, or with an oral ‘Benzimidazole’ product. Targeting the farrowing house has the advantage of maximising energy status of the sow at the most important time. We believe this approach is giving us improved performance in the sow herd where we have put it in place.

Milk spot – Ascaris suum!Milk Spot

Ascaris suum is the most commonly recognised parasite in pigs, it is also the most economically important. Ascarid worms live in the gut, but during its lifecycle it migrates through the lungs and the liver, giving the classic “Milk Spot”; this migration results in lung damage, coughing and condemnation of livers at the abattoir. Ascarids in finisher pigs are generally better controlled than worms in sows. However, we still see plenty evidence of Ascaris suum infection in the abattoir; considering the effect of infestation on the lungs, liver and increased FCR, it is key that we worm our growing herd efficiently.

Please speak to your vet about the best approach to monitoring and control of worm burdens on your farm!

Courtesy of The George Vet Group


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