Westgate Vet Carolyn Cummins Talks Foal Health
21 March 2018
And why proactive worming is so important
“While foals and weanlings are literally just mini horses, the worms that they are likely to be infected by and the treatments for them can be very different” explains Carolyn Cummins MVB Phd MRCVS.
WORMS & The immune system
Foals and youngstock have immature immune systems so can be susceptible to certain parasites that do not usually affect adult equines; namely Strongyloides Westerii (Threadworms) in very young foals and Parascaris equorum (roundworms) in older foals and weanlings.
These worms are found all through the general horse population but don't usually cause illness in healthy adults. Because of the vulnerability of young horses we assume that all foals are likely to become infected and treat accordingly. While in adult horses we recommend testing before treating, it is different for foals as they are so likely to succumb to parasite infection and the effects can be so devastating it is better to treat as a preventative rather than wait for signs of disease.
Choice of wormer
Worm infections in youngstock can very quickly become severe and so it is important to have an appropriate parasite control program in place. Foals should start their worming programme at 4 weeks of age, however, some foals younger than this may shows signs of infection (diarrhoea/scour). These foals should be seen as soon as possible by your vet as any scouring foal can quickly become dehydrated. They will be able to test for the cause and advise appropriate treatment.
Choice of wormer is very important in young stock. While tempting to just give the same wormer that you are using for all your other horses, the drug that you are using for adult animals may not be appropriate for the foal as they may be at increased risk of toxicity/overdose. It also may not be appropriate or effective for the parasite you are trying to control. Fenbendazole (Panacur) is a very safe wormer in young animals and overdosing is very difficult to do. Luckily it is also more effective against roundworms than ivermectin/moxidectin and so it is our first choice wormer for foals.
long term Effects of worm damage
Worm burdens can be a silent threat to the wellbeing of young horses, causing acute life threatening conditions as well as chronic intestinal scarring, digestive and respiratory issues. Any damage is usually life long, impacting the take up of nutrition, stunting growth and compromising a horse’s system so that it becomes a ‘poor doer’ with the potential to impact the athletic ability of even the best chosen bloodlines. It is not uncommon to see that the horses with the poorest start in life are the repeat offenders as adults with high worm egg counts.
Starting a good worming programme for your youngstock will help set them up for life. Incorporating worm counts and tests into the programme early on will help to identify the wormy horses and those that are going to need more support, preventing any problems developing from unnecessary parasite burdens. This will help your youngsters to reach their full potential as happy, healthy horses.
Our congratulations to the team at Bullimore Eventing on the arrival of Savannah, pictured above. Savannah's mum, Evie was given a moxidectin wormer 4 weeks before her due date or the alternative is to give an ivermectin around foaling time to protect against threadworm infection.
Proactive worming is important for pregnant mares and young foals. Any questions please ask!