Worming horses?

Discussion in 'Horse Management' started by Remaani, Jul 11, 2008.

  1. Remaani

    Remaani Guest

    In regards to Pinto Lover's thread re Halter Breaking foals..... i am curious about the management of foals & worming.

    At what age do breeders worm their foals?

    Is it true that if not worming till weanling age, the wormer is passed through to the foal, in effect not needing to worm the suckling foal?

    If you dont worm till weanling age, do you feel your foals are still healthy, do they display a "wormy" look to them? Have you seen them pass worms?

    Please no debates on which way is best.... righto!! ;)

    (for the record, i worm from suckling age, not when weaned)
  2. dun

    dun Active Member

    What we do

    We drench mare before she foals and then foals get drenched at 6 weeks of age and thereafter.
  3. saltriver

    saltriver Guest

    We wean all our foals at 4 months and we havent had a problem with our foals having a heavy worm burden.we drench at weaning time.
    We have had faecal flotations done and a worm count.

    There is a photo on my website in the yougstock section of Saltriver Limelight she is 5 months and looks pretty healthy to me.

    what we find in our area is that our horses require worming as the grass gets to be around 1.5 to 2inches from the ground. as this is where the worm eggs are.

    we also rotate our dreching from a mectin to panacur (wich doesnt do bots)so we time it to the botfly season.

    I also as a breeder would be interested in others opinions on this.
  4. mylittlepony

    mylittlepony Well-known Member

    ditto**) we do the same with our foals
  5. sil

    sil Gold Member

    Mum gets drenched regularly and the foal gets it at about 3 months of age.
  6. citygirl

    citygirl Gold Member

    I worm before the mare is due to foal...

    weaning depends on the mare & foal { on how well they're both doing condition wise} and I worm the Dams while foal is at foot..if there is a problem with worms...then the foals will get wormed seperate from their Dams { so the foals get wormed twice ?? lol }

    then EVERONE gets wormed every 6 to 8 weeks with rotated wormers.

  7. wormwatch

    wormwatch Active Member

    If you wait until horses "look wormy" before treating them then the damage to the lining of the gut and other internal organs is already done and pasture will be heavily contaminated with worm larvae that will immediately reinfect the horses after treatment.

    Salt River has good advice about using worm egg counts and an effective preventative treatment program to prevent harmful burdens developing in the first place.
  8. Pjsarabs

    Pjsarabs New Member

    We worm preg mares 4 weeks pre foaling, (no more than) 2 hrs post foaling, foals at 5-6 weeks, and then they are on the regular rotation.
  9. retroremedy

    retroremedy Well-known Member

    While it is possible for some drug to be present in breast milk, it would not be in any way an amount that would have therapeutic ability.
  10. GeeJay

    GeeJay Guest

    It all depends on how your horses are run and the amount of land you have.

    At our other farm our mares, foals and Stallion were on a 20 acre paddock, mares were wormed at weaning time then turned out into a fresh paddock then halfway into pregnancy if required.

    Foals are wormed on weaning then on a seasonal basis eg at each break of the seasons.

    Now our mares run on 6000 acres but we still use the same method. Rotation is very important and having clean healthy paddocks. We have noticed often a sudden change in diet horses pass worms.

    The one thing we find important his worming for the correct weight so we always stand them on scales, as under dosing can be detrimental.

    Doing a worm count to me is very important as over worming is as harmful as not worming enough.

  11. Remaani

    Remaani Guest

    Thanks RR, thats what i was curious on.

    Now my thread was about foals, but the inlaws had 2 mares for 11 & 12yrs on the 1 paddock (about 50 acres), they were never wormed (because FIL didnt know horses had to be wormed)..... they were fed hay couple of times a week.
    They were a picture of health, infact a bath & rug & you could take them out showing & they looked better conditioned than a few show horses.
    In that paddock, they had NO contact with my other horses. They looked great, short shiney coats, fit, happy, healthy.

    Since i took them on (& only 1 now :(), all worming & teeth care have been up todate, they still look good but since worming, i've found no worms... she now has contact & paddocked with my other mares.

    Anyway, i wonder wether horses (well foals ;)) can have worms, but just not look it.
  12. PINTO1980

    PINTO1980 Gold Member

    I havent read any of the replies...

    Chloe got drenched at about 2 days after giving birth..Vet said Foal would be fine and would get wormer etc through milk...

    Zayn got his first worming at 3months.
  13. wormwatch

    wormwatch Active Member


    You generally won't see dead worms in manure, particularly the small strongyle worms that can cause damage to the lining of the large intestine. You also won't find the immature large strongyle worms that cause colic and organ damage by blocking blood vessels as they migrate around the body.

    Horses with large worm burdens generally look "wormy" because of damage to the gut and other organs. Even after treatment, this damage may not fully resolve and the damage may be permanent.

    Prevention of worms using a combination of carefully timed treatments, pasture management and monitoring with worm egg counts is the best way to prevent disease and build up of worm populations in horses and on pasture.
    Last edited: Jul 12, 2008
  14. wormwatch

    wormwatch Active Member

    Foals pick up most types of worms when they eat/swallow the infective stages that are in the environment, usually on pasture. The exception in threadworm (Strongyloides) that can pass from the mare to the foal in milk. Your vet wouldn't expect to find a large worm burden in a 2 day old foal, but there are two ways to approach controlling strongyloides in foals - treat the mare with wormer effective against migrating stages of strongyloides within 24 hours of birth OR treat foal with wormer effective against strongyloides at 1-2 weeks of age. So by treating the mare soon after foaling, you are stopping the mare from infecting the foal with immature strongyloides in her milk by killing any worms in her udder rather than "treating" the foal as such.

    Ascarids (roundworms) can build up in foals and cause intestinal blockages. They can also cause problems when they undergo their migration. The female worms are generally able to start laying eggs about 10-12 weeks after infection - treating within this interval will break the cycle if you use the right treatment. The eggs are really tough and can survive in the environment for a long time (more than 10 years in some studies) so treating foals at 1.5-2 months of age (depending on the wormer) and then every 2 months is often recommended, both to prevent disease and stop the foal from shedding eggs into the environment. Ivermectin is effective against the immature and mature ascarids.

    Ascarids (roundworms) are interesting worms - well i think so anyway :)
    1. When a foal swallows an egg, the immature worm hatches in the gut
    2. Then it burrows into the lining of the gut
    3. Then goes on a journey to the liver (either in a blood vessel or a lymphatic vessel) where it has a rest (about a week)
    4. Next it finds a blood vessel that it uses to go to the lungs
    5. Once it gets to the lungs it exits the blood vessel then wriggle out of the little air sacs into the airways and up the trachea (windpipe)
    6. Once it gets to the top of the trachea and into the throat, the horse swallows it (again)
    7. Then it ends up in the gut again so it can mature, mate and lay eggs (if it's a female) - at the same place where it started in step 1
    8. Egg passes out in manure ready to start all over again.

    Foals can also become infected with other worms such as large and small strongyles, tapeworms, pinworms etc so it's worth getting some professional advice on what worming program is right for your horse. Recommendations for worming foals varies so you should ask your vet what is appropriate for your specific situation.
    Last edited: Jul 13, 2008
  15. ashka

    ashka Well-known Member

    Worm Watch has some interesting information! When working at an animal health company, I was also told that the mare provides the greatest source of contamination to her foal through milk. The bits I remember about worming foals are pretty scary - foals quite often die from heavy worm burdens on properties where the adult horses appear healthy. If you can try and worm the mare two weeks prior to the estimated foaling date and then worm both the mare and foal in 8 weeks time, you should have a pretty foolproof schedule. Just as an aside - use the safest product with published safety data in mares and foals! Equimax and Equimax LV have been thoroughly tested at up to five times the recommended dose in foals and at three times the recommended dose every 14 days in pregnant mares.
  16. Noelle

    Noelle Gold Member

    This may sound silly but how does a horse get worms in the first place? Does a horse normally have worms anyway or is there some stage at which they are totally worm free? I guess if there is a stage when they are worm free then how do they get the worms?

    For example if there is a paddock clean of eggs and a horse is clean of worms; the horse is put in the paddock would he remain worm free?

    If a horse has worms normally then is it a case of keeping on top of them so it doesnt become an issue?

    Also, when is the bot season?

    And another question, how often do you rotate your wormers? One person told me you use a wormer with a different acting agent each time; then again someone told me use the same wormer for 12 months and then change to another for the next 12 months. So now I am totally confused. :confused:
  17. retroremedy

    retroremedy Well-known Member

    I will leave your questions to WormWatch to answer as they will give you a very profession run down on worms. :)

    I think everyone should get a worm egg count done to get a snap shot of the worm burden of their horses. I encouraged one of my friends on the weekend and the results came back as a massive shock for them as their horses had a very high worm burden. It is just a really sensible thing to do as it takes the guess work out, it helps with rotating wormers and being strategic with worming. Worms can do so much damage and wormers can be very expensive on your pocket so knowing where you stand by getting a couple of worm egg counts done is really cost effective in the long run!
  18. Noelle

    Noelle Gold Member

    Hmmm - funny you should say that. I mentioned it to my vet once and he discouraged me from doing it ??????? So how do you do that?

  19. retroremedy

    retroremedy Well-known Member

    hahah well it was actually my vet that recommended worm egg counts to me as I was having problems with one of my horses. The number of people I have recommended spending a sample has proved that it is very vital as a good percentage have come back with unhealthy levels (a couple had very scary levels!!) and have revealed to many that they have to take their parasite control more seriously. I dont think people realise that it is only when things get very very bad that the horse shows symptoms and it means damage has been done.

    WormWatch is who you speak to about worm egg counts. I normally post my samples in to them and the results come back in a couple of days via email with full report and recommendations.
    Last edited: Jul 16, 2008
  20. wormwatch

    wormwatch Active Member

    It depends on the parasite.

    The most common worms of horses are strongyles and horses become infected when they ingest larvae (immature worms) with pasture. The larvae come from eggs that are passed in the manure of an infected horse. These are the eggs that are measured with a faecal worm egg count.

    Round worms lay eggs that are also passed in manure. These eggs are sticky and tough - they can last 10 years or more out in the open. The horse becomes infected when it swallows the egg. The eggs can be stuck to any surface they come in contact with so grazing pasture it not necessary for horses to become infected with roundworms.

    Horses are infected with tapeworms when they swallow mites that live in pastures that are carrying immature tapeworms. The mites are very common.

    It is unusual to find horses that are completely worm-free. Most treatments do not kill all stages of all worms nor the entire population of the worms that they are targeted against. For example, the small strongyle worms have a stage in their life-cycle where most worming treatments are not effective at killing the immature worms. If you wormed this horse and placed it on totally worm free pasture, the larvae may finish their development at a later date and re-start the infection cycle. A study conducted in Perth and published in 2000 found that 28/29 horses (97%) were carry some small strongyles. Other studies worldwide find similar numbers (95%+).

    Also pastures are unlikely to remain "worm free". Worms can survive a long time in manure so it is difficult to prepare completely worm free pastures and keep them that way if you consider 97% of horses are carrying some worms.

    Exactly :) That is the role of worm egg counts - to measure how well your control programme is working. if you don't check - how do you know that your treatments are effective? By monitoring, you can check if everything worm control is working well and if not, make the changes necessary to improve your worm control before the horse develops harmful burdens that can cause disease.

    Think of parasite management as "control" rather than eradication. It's hard to erradicate worms unless you live in a bubble, so the best approach is to manage them effectively so that the numbers never get a chance to build up to a level where disease is likely.

    Usually in southern Australia the bot flies are most active in autumn and surveys have found that the number of bot larvae recovered from horses peaks in the winter months.

    Rotation of treatments with each/every treatment was recommended in the olden days, not to slow resistance but because many of the treatments available then were not as effective at killing as many types of worms as the more modern treatments. By switching chemicals each time, it covered the worms missed by the previous treatment.

    Some parasitologists recommend slow rotation between chemical families to try and slow the development of worm resistance to chemicals. This would mean using one group one year and change the next - a "slow rotation". This approach does come with some warnings though:
    - not all worming families/treatments cover all the important parasites present in horses in WA so you may need to include some additional treatments chosen to prevent problems caused by the "missed" parasites
    - there is widespread small strongyle worm resistance to many chemicals throughout the world so it's important to monitor the effectiveness of your control programme to make sure that harmful burdens are not building up due to resistance to the treatments used in the rotation

    Hope this helps - PM me to receive the Worm Watch newsletter that has more information on what you can do to effectively manage parasites.

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