Rainy warm weather is ideal for worms! Read why…..
The rain followed by the warm weather combination is ideal for the larvae to develop inside the eggs. The wet weather also means we have not dried off in central otago yet as we normally would in the summer months.
I have a lot of clients, based on consistently low faecal egg counts, that only worm in the spring and autumn (twice yearly) which is fantastic. However, I would highly recommend that this summer, everyone performs faecal egg counts to ensure your paddocks do not develop high contamination levels of worm eggs. This would be disastrous for the cooler months, as large number of immature worms will be present during autumn. These immature worm stages can then hibernate in the walls of the large intestines. They are then at risk of all emerging in the spring all at once and causing disastrous effects on the bowel wall. This can cause a fatal diarrhoea.
What is a red worm
The fancy word for a red worm is a ’Cyathostome’. In spring, these little parasites can cause a real problem in our adult horses by damaging the gut wall and causing serious diarrhoea. Here is how they do it:
As with most other worms, your horse will pick up eggs from the pasture while grazing. These eggs end up in the gut where the larvae emerge. As part of larval development, one larval stage burrows into the gut wall before emerging back into the gut lumen, where they become adults and start laying eggs.
When the outside temperatures start to lower in autumn, the larvae that have burrowed into the gut wall become somewhat dormant and remain there until temperatures start to rise in spring. It’s a great way for the parasite to hide away from the cold! This also explains why egg counts in winter can be very inaccurate, as minimal numbers of larvae develop into adults to lay eggs. The damage of the gut wall and associated diarrhoea happens in spring when all the hibernating larvae emerge from the gut wall at once.
Having a correct worming programme in place will minimise the numbers of larvae overwintering in your horse’s gut wall. Wormers have less effect on hibernating larvae compared to adult worms. Therefore, we want to worm our horses before the weather starts to cool and the larvae start to hibernate. Keep low numbers of eggs on the pasture by regular monitoring of faecal egg counts ensures a low risk for large numbers of over wintering larvae.
Tips to prevent this:
Firstly; continually monitor your poo counts to ensure your pastures stay free of eggs
Secondly; ensure that you know the contamination level of your paddocks because it will help me make the correct worming plan for you.
Thirdly, most of my clients are not aware that you receive a FREE and CORRECT worming programme and support when you perform egg counts with us. Sadly I still see a lot of incorrect advice and poor wormer selection.
Lastly; the reason we keep the egg count output low in our horses is so that a large number immature worms (larvae) do not hibernate over the winter!