Equisal results high, but WEC always zero. How come?

supsup

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I'm a bit puzzled by the results I'm getting from testing for worm eggs and using the EquiSal test for tape antibodies. Over the past 8 years, the WECs have always returned as "no eggs seen" (with one exception of 50epg), so I think our management is pretty good. A year ago I started using the EquiSal test instead of routine treatment with Equitape twice a year, despite my vet not being convinced that the test is mature enough to be useful.
Anyway, the first test returned a negative result (a year ago), but I got a medium/high result last spring (Equitape treatment followed) and again just now. The saliva score was higher in the spring than it is now, so it hasn't just kept on going up (which I'm guessing might indicate that treatment isn't working?).
Considering the cost of the EquiSal test (twice the price of the wormer) I'm wondering if I shouldn't just go back to treating twice a year. I'm not sure there's anything I could do in terms of field management that might reduce the chances of getting re-infected with tapes. Could my horse just have poor immunity against tapes? Any other likely explanations? I will try treatment with pyrantel-based wormer this time.
 
They are different tests so one only does tape, the WECs do the rest (except encysted redworms).

I think it's a good idea to keep testing for tape. They come back just like other worms. They lay eggs and are in the ground so you never eradicate them.
 
Tapeworms are totally different to the other parasites, they are unlikely to be completely eradicated by a worming programme, poo picking has little influence on the life cycle as they are picked up by the horse through ingesting the harvest mite host so can be constantly exposed through grazing or eating hay, therefore if you are getting high results the chances are you will need to worm for tapes routinely as you cannot really do anything to stop the horse being exposed to the lavae unless you know the forage is from clean pasture, it may be that your most recent hay supply is the cause of the problem.
 
Yes, I do understand that the two tests are unrelated. But I would have thought that the management practices that are good to reduce reinfection for one are the same as for the other (i.e. poo picking, stable herd, cross grazing; higher risk if grazing at other venues...). If management is demonstrably good for regular worms (very long term low WECs), why would the same management be poor for limiting reinfection with tapes?

The only reason I could think of is if the horse's immune system is just better at naturally fighting off one parasite vs. another, and if that's the case, then treating a susceptible horse on a schedule doesn't sound like a bad choice. We had a pony with very high worm burden in with our herd for a while, and yet my horse did not pick up any. I put this down to his immune system being quite robust that way. Maybe he is much more susceptible to tapes?

I guess I just feel disappointed that the EquiSal test isn't more useful in devising a strategy to reduce the need to treat for tapes in the future. At the moment, I pay £18 every 6 months for what feels is a complete gamble on whether to spend another £15 or not. So far, this gamble hasn't been in my favour 2 out of 3 times, and I'm not provided with any information on how I can improve my chances of not having to worm next time around.

ETA: only just saw be positive's post. That makes sense.
 
Yes, I do understand that the two tests are unrelated. But I would have thought that the management practices that are good to reduce reinfection for one are the same as for the other (i.e. poo picking, stable herd, cross grazing; higher risk if grazing at other venues...). If management is demonstrably good for regular worms (very long term low WECs), why would the same management be poor for limiting reinfection with tapes?

The only reason I could think of is if the horse's immune system is just better at naturally fighting off one parasite vs. another, and if that's the case, then treating a susceptible horse on a schedule doesn't sound like a bad choice. We had a pony with very high worm burden in with our herd for a while, and yet my horse did not pick up any. I put this down to his immune system being quite robust that way. Maybe he is much more susceptible to tapes?

I guess I just feel disappointed that the EquiSal test isn't more useful in devising a strategy to reduce the need to treat for tapes in the future. At the moment, I pay £18 every 6 months for what feels is a complete gamble on whether to spend another £15 or not. So far, this gamble hasn't been in my favour 2 out of 3 times, and I'm not provided with any information on how I can improve my chances of not having to worm next time around.

ETA: only just saw be positive's post. That makes sense.

You can't. Thats why worming regimes existed.

I think you are right about natural immunity and I think some horses are definitely more susceptible but the whole point is that you know you're treating a real burden rather than just piping it in regardless.
 
My vet did not recommend the EquiSal test, we had a blood test for them as well as a poo sample for the other worms, and he gave me the all clear for Tapeworm. Like you, our worm counts have been zero for years, so it would seem that good practice has controlled both as although he may come into contact with it, there is little chance for re-infection.

If you are concerned then I would ask the vet for the blood test.
 
nothing you can do management wise to reduce tape reinfection after treatment.

IIRC there is no reported resistance to praziquantel, there is to pyrantel.
 
Westgate stated in one of their FB posts that they've seen cases either way where horses still had a burden after praziquantel that responded to pyrantel, and vice versa. Hence my thought to try the other one, just in case it makes a difference.
C
FWIW, our horses haven't been fed hay (apart from the occasional haynet from the same stash) since last winter. Considering the saliva score was higher in spring than it is now, maybe the load of hay we had contributed.

I guess the optimal solution (at least from my point of view) would be for the price of the test to drop to a level that doesn't make feel like I'm wasting too much of it doing the "responsible" thing testing every time, even if I think I am likely to have to pay for the wormer on top of it.
 
I rotate, use one then the other :) but if your tests are 6 months apart you are looking at reinfection rather than the treatment not working, you would have to do tests much closer to show it wasn't working (and not the equisal test probably)/
 
Resistance is real.

There is nothing beyond what we have. No matter what regime you stick by... these worms may, or may not, develop resistance.

One day, there will be nothing. I worked for Merck btw. I know this. Eradication has not worked. We will be in a situation where we can't treat.

As a horse owner, I advocate testing 100% no matter what you use, who you use and how. But I know in the long term it's not bright.
 
This link below should help you understand the test

https://www.vetstream.com/equis/Content/Technique/teq00824.asp

One important aspect to consider is "Horses with 1-19 tapeworms are classed as having a moderate burden and are included together with the high burden (>20 tapeworm) group for statistical analysis and reporting"

This means that your horse could only have one tape worm and they may still get a moderate/high result.

As others have said tapeworm is different from normal worms as the larva live in host which is a mite. These mite are mobile so they can move around from field to field I expect they could get on their legs out hacking or at a show. If your field is next to another field or bridleway where there are horses the mites could move between fields and they can get into the hay as well. As you can see from this article from equimax they are also often found in hay and straw too.

http://www.equimaxhorse.com/parasites/tapeworms/

My pony got very ill from a tapeworm infestation and the vets were not sure what the problem was at first as he had a low worm count and had had had the recommended number of tape wormers a year. Turned out the whole herd had a bad infestation but the others were not showing as extreme symptoms as my pony.

I am on a different yard now and the field management is really good as poo picking is included as part of the livery so the fields are cleaned on a regular basis. However I still use the equisal test as he could still get tapeworm from hay, even though he is on good quality steamed hay {I presume the heat involved in steaming hay may kill the mites and tapeworm larva?}. As he got so ill last time he had a high tape worm burden I am careful and he has the equisal test and I rotate wormers as well so this time he had Pyratape P.
 
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