Encysted strongyles protocol - what would you do?

[alishaarrr]

I recently started working with a new trainer who takes a very in-depth, holistic look at the overall health and well-being of horses they come across - which I appreciate. He has a strong suspicion that my 8yo OTTB has encysted strongyles: he has a hay belly but poor topline (nothing over his spine and some muscle wasting over his HQ) despite a quality, nutritionist-formulated diet (free choice hay, alfalfa pellets+oil+balancer+probiotics), 12h turnout on hilly terrain, and regular, reasonably correct work.

My horse was last tested in the fall and was a zero shedder, dewormed with Ivermectin – so would not have addressed encysted strongyles (which I understand do not show up in FECs).

Said trainer apparently encounters this regularly in our area (NoVA) and has worked with his vets (?) to develop the following protocol for treatment:
Day 1: Ivermectin
Day 8-12: Pancur Powerpac
Day 13: Quest
Day 23: Quest Plus

According to him, this eradicates the strongyles at all stages of their life cycle, including as the cyst/encapsulation is disturbed and the parasites are then expelled elsewhere in the horse’s body where they can continue to do harm, and accounts for any drug resistance. This all makes sense to me, but also seems quite aggressive compared to what I have read about current standards for encysted strongyles treatment.

I have a vet appointment in a few days and can raise this with my vet. I am anticipating some skepticism of the non-standard (I think?) protocol as well as the fact that my horse may not have significant symptoms other than his body condition (and weird shedding for this time of year). Also trying to sort out my own thoughts on what feels right here. I suspect this is going to be one where I have to advocate for my horse with the vet. The other option is to just do the course of treatment without involving the vet, and then he’ll get a standard dose of whatever they treat with based on his fecal count later in the fall, which shouldn’t hurt him.

Any reactions or thoughts here?

[Amberley]

@alishaarrr

encysted strongyles treatment

Moxidectin (Quest) will get rid of these. No other wormer is effective on them at this time that I know of.

[alishaarrr]

@Amberley

@alishaarrr

encysted strongyles treatment

Moxidectin (Quest) will get rid of these. No other wormer is effective on them at this time that I know of.

According to the Merck literature for Panacur Powerpacs, Quest only addresses 2 of the three larval stages for encysted small strongyles: https://www.merck-animal-health-usa.com/offload-downloads/a-guide-to-deworming-maximize-your-horses-health-from-the-inside-out

[Posting_Trot]

I would go just with Quest or QuestPlus (if you suspect the horse might have tape worms).

The Panacur PowerPac probably will not have much effect. Even though, originally, it targeted a wider range of encysted strongyles, strongyles have developed such resistance to it has made it ineffective.

I (personally) wouldn’t do all of these wormers back to back either. It’s a lot of medication to dump into a horse in the span of three weeks.

[JB]

@alishaarrr

Said trainer apparently encounters this regularly in our area (NoVA) and has worked with his vets (?) to develop the following protocol for treatment:
Day 1: Ivermectin
Day 8-12: Pancur Powerpac
Day 13: Quest
Day 23: Quest Plus

Oh lord no, please no. I don’t know why this is such a popular protocol. Nothing about NoVa would make this issue more prevalent either

Use Quest Plus and be done with it

Ivermectin - useless for encysted strongyles
PP - not likely to be all that effective anymore due to resistance. Could be, might not be
Q - if PP WAS effective, there’s nothing for Q to do. If it WASN’T, they just use Q in the first place
QP - WHY??? Assuming at least the PP or Q was effective, what’s left for QP to do? The only thing it has that the other 3 rotations don’t, is to kill tapeworms. If they’re an issue, just use Quest Plus to begin with

Even though moxidectin doesn’t kill 1 staged of encysted larva, missing that is highly unlikely to cause issues. Better to be more effective against the other stages of EL, than likely pretty ineffective against all of them

@alishaarrr

According to him, this eradicates the strongyles at all stages of their life cycle, including as the cyst/encapsulation is disturbed and the parasites are then expelled elsewhere in the horse’s body where they can continue to do harm, and accounts for any drug resistance.

Uhhhh, no. Yes, this would take care of most of all the stages, But the encysted/encapsulated starts aren’t “expelled elsewhere in the horse’s body…and accounts for drug resistance”

You either kill the encysted larva (EL) stages, or you don’t. If you do, they’re not going anywhere but out. If you don’t, then they’ll emerge as adults and continue along as adult strongyles, shedding eggs to be seen in FECs, etc. Nothing to do with resistance.

If you want, just use Quest Plus, especially if “My horse was last tested in the fall and was a zero shedder, dewormed with Ivermectin” is the last time he was dewormed. I’d be more concerned about tapeworms than encysted strongyles.

Low shedders get Quest Plus in Spring, Equimax in Fall, in our general area (southeast, I’m in NC). That takes care of bots and tapeworms each time, without always using moxidectin or ivermectin

@Amberley

Moxidectin (Quest) will get rid of these. No other wormer is effective on them at this time that I know of.

When both were fully effective, a PP targeted all stages of encysted larva, while moxidectin didn’t target one of them (and I never remember which one), but it wasn’t a big deal because the odds of there being SO many of that stage as to continue causing a problem is almost 0

@Posting_Trot

I (personally) wouldn’t do all of these wormers back to back either. It’s a lot of medication to dump into a horse in the span of three weeks.

Not to mention it’s a pretty ridiculous rotation given what each does and doesn’t do, as well as resistance issues.

[luvmyhackney]

@alishaarrr

poor topline (nothing over his spine and some muscle wasting over his HQ) despite a quality, nutritionist-formulated diet (free choice hay, alfalfa pellets+oil+balancer+probiotics), 12h turnout on hilly terrain, and regular, reasonably correct work.

Not every horse does well on this diet and some need more calories than what a balancer/oil and grass hay provides. Give the horse a tube of Quest Plus, some ulcer meds and add some green PA or Western WV alfalfa to put weight on prior to winter.
I’ve boarded in NoVa and currently board one horse in NoVa, its not common. I kinda want to know what vet he works with to create this crazy worming schedule.

[JB]

I would test for PPID just to rule it out. I know of one 4yo, and a couple of 5yos who were diagnosed (properly)

When did this wasting start?

[Scribbler]

@alishaarrr

I recently started working with a new trainer who takes a very in-depth, holistic look at the overall health and well-being of horses they come across - which I appreciate. He has a strong suspicion that my 8yo OTTB has encysted strongyles: he has a hay belly but poor topline (nothing over his spine and some muscle wasting over his HQ) despite a quality, nutritionist-formulated diet (free choice hay, alfalfa pellets+oil+balancer+probiotics), 12h turnout on hilly terrain, and regular, reasonably correct work.

My horse was last tested in the fall and was a zero shedder, dewormed with Ivermectin – so would not have addressed encysted strongyles (which I understand do not show up in FECs).

Said trainer apparently encounters this regularly in our area (NoVA) and has worked with his vets (?) to develop the following protocol for treatment:
Day 1: Ivermectin
Day 8-12: Pancur Powerpac
Day 13: Quest
Day 23: Quest Plus

According to him, this eradicates the strongyles at all stages of their life cycle, including as the cyst/encapsulation is disturbed and the parasites are then expelled elsewhere in the horse’s body where they can continue to do harm, and accounts for any drug resistance. This all makes sense to me, but also seems quite aggressive compared to what I have read about current standards for encysted strongyles treatment.

I have a vet appointment in a few days and can raise this with my vet. I am anticipating some skepticism of the non-standard (I think?) protocol as well as the fact that my horse may not have significant symptoms other than his body condition (and weird shedding for this time of year). Also trying to sort out my own thoughts on what feels right here. I suspect this is going to be one where I have to advocate for my horse with the vet. The other option is to just do the course of treatment without involving the vet, and then he’ll get a standard dose of whatever they treat with based on his fecal count later in the fall, which shouldn’t hurt him.

Any reactions or thoughts here?

Agree, you need Quest Plus which actually makes the encysted strongyles let loose and be pooped out rather than dying in situ. Note that when they are encysted they are dormant larval form typically over the winter.

Also you have poor doing TB. He’s going to need more calories, horses can burn off a lot in hilly pasture. Also don’t work him in this condition, he can’t put on muscle while he’s under weight.

The cool calorie products that are alfalfa meal and vegetable oil pellets are calorie dense and palatable.

Honestly I’ve never seen a pet horse with even infrequent worming that had a worm load that caused weight issues. What I have seen at many boarding and lesson barns are horses chronically underfed or undernourished that just need more or different feed. Also horses with chronic pain can be anorexic.

I would also look really closely at his vitamins and minerals. And ulcers

Free choice hay is all very well but some TB can’t or won’t eat enough to keep themselves in good condition.

Moral of the story: if the plan your nutritionist devised is making your horse look like crap, change it ASAP. If the working protocol your trainer suggests is wacky trust your vet. If your trainer is in charge of the horses diet, and trying to shift blame to “worms” then move.

[SusanO]

To be the devil’s advocate here - you know what contributes to lack of topline and wasting in hindquarters - not carrying behind and working over the back because the hocks or stifles hurt. Every time I see a horse muscled like this I wonder about adequate nutrition and even more - do the hocks hurt? Maybe not enough for the horse to show up as lame but enough that he does not want to articulate the joints and carry weight behind. Could he maybe have the start of mild arthritis somewhere in the hind end?

Or maybe the protein in his diet is not adequate for the work he is expected to do. Poor quality hay and inadequate amino acids can give the pot belly look, not just a big worm burden.

[trubandloki]

All the other topics have been addressed so well. It is great @alishaarrr that you realized this deworming protocol seemed weird.

Shedding this time of year is normal, BTW. The days are getting shorter. Their bodies are starting to plan for winter.

[alishaarrr]

Hi everyone, just wanted to say thank you for the replies and for confirming my instincts that this protocol was overkill (pun intended).

I had the vet out yesterday as we’re also dealing with some grumpiness that could be ulcers or could be lyme, and ran this by her. She said this layered protocol is somewhat common, but as above, indicated that the Panacur really is not helpful given how prolific the drug resistance is with strongyles at this point, and that Quest should do the trick if that’s what we’re dealing with.

In terms of his overall condition, vet wasn’t concerned – said he looks like a horse with a big ribcage who is in “moderate work”. He’s working much more correctly over the past few months and our saddle fitter said he’s filled out some, so I’ll take a second look at diet once the immediate issues are sorted out but otherwise hopefully we are on the right track.