Ok to not use Panacur Powerpacs in your rotation?

[filly78]

We recently moved our horses home and have since taken over worming our guys every 8 weeks as per our vet's instructions. Vet has the 5 day Panacur PowerPac listed to use in April. Our guys are backyard horses, 2 big guys, 2 minis, and are not exposed to other horses on or off the property. Pastures are picked on a regular basis.

Is is always a good idea to use the 5 day Panacur PowerPac once per year or would I be ok using the 1 dose Panacur instead?

[billiebob]

We do the once a year powerpacs and I do like having that "flush" for them. I don't think it'll hurt to do the 5 day, although I know it's expensive.

[sublimequine]

I've never used the Powerpac. Somehow my mare has survived. ;)

[Posting Trot]

The PowerPack targets encysted strongyles. These can live in a horse's gut for several years, and no other wormer (aside from moxidectin--Quest) will kill them. At some point, they will begin to break out of their cysts; they often do this all at once in response to some environmental trigger. If there's a substantial number of them, they can cause a horse to colic, bleed internally, etc.

The Powerpack is a pretty minimal investment; one alternative is Quest. It doesn't target the full spectrum of encysted strongyles but it does a pretty good job. And it's only one dose.

[filly78]

I do currently use Quest in our rotation - only for the big guys though, not for the minis...

[jaimebaker]

I've never used the Powerpac. Somehow my mare has survived. ;)

None of my 6 have ever been Powerpacked. I've been considering it but like you, I have a closed herd that don't go anywhere. I've had them all since they were foals. I've never Powerpacked any horse I've ever owned. Never heard about it until I came here.

I may do it but I've talked to two vets that deal with my horses and they say for mine they certainly don't 'look' like they need it (fat, shiny, healthy, great hooves, no skin problems, etc...knock on wood!). I still might do it this Spring though. Just for good measure. I'm interested to hear what others say in this thread though.

[Simkie]

I generally do a powerpac about once a year, and if I forget, I notice my horse getting unthrify about 18 months post power pac--and this is WITH using Quest in rotation.

I would not skip a power pac once a year.

[scpezold]

I have 3 at home and just finished doing 5 day "purge" on them. Although I use Strongid C2x daily and Zimectrin Gold twice a year I always purge them to ensure no worms got "immune" and survived. I buy the cattle doses (big tubes) of Safeguard. I figure out there weight total and multiply times five to figure how many tubes I need. I think I got four or five tubes this year. It is the same as the Panacur Power Pak (results are the same) but the PPP is a more convenient method (failsafe) therefore the cost is greater. If this is new to you (BO administered before) I would probably go with the PPP just to be safe. However, I always add a little more to each of there doses just in case.

[sublimequine]

I do hear that Powerpacs are safer than Quest. Anyone know why? :confused:

[bugsynskeeter]

It is much easier to "OD" a horse on moxidectin then fenbendazole.

[Simkie]

It is much easier to "OD" a horse on moxidectin then fenbendazole.

It still takes quite a bit. The safety index for moxidectin is 5, IIRC. You'd really have to TRY to overdose your average horse.

Sublime, I've heard a couple things with regard to Quest vs. Power Pac. I've heard that moxidectin paralyzes the worms and they're flushed out of the body with no inflammatory response, whereas a Power Pac kills the worms and that triggers inflammation in the gut. I've also read that a Power Pac is *easier* on gut because it kills the worms over several days vs all at once.

In MY experience, I've never had a negative reaction to a power pac--and I've dosed horses with VERY questionable worming history. I've also never had a negative reaction to Qwest, but I've never dosed a horse with questionable history with it until they have a history with me.

And I've absolutely, certainly seen my horses start to look poor about 18 months following a power pac if I forget to dose them at a year, even with using Quest. The horses have, without fail, improved following a power pac.

[JB]

I do hear that Powerpacs are safer than Quest. Anyone know why? :confused:

Depends what you mean by "safer" ;)

Mox has a lower safety margin, and should *not* be used on young, sick, old, OR underweight horses (as it needs enough body fat to properly metabolize and not be an "overdose" at even a normal dose).

But, all else equal, there are 2 differences between the 5 day double dose fenbendazole, and a 1 time moxidectin.

1. 5 day double dose - gets the third stage encysted larva that mox *does not* get
2. Moxidectin does not cause the mucus inflammation that occurs around Day 14 (from the first dose) when using the fenbendazole protocol. That inflammation mimics the emergence of the encysted strongyles (not CAUSING it, the symptoms mimic it) and can make some horses colicky.

I personally have not had #2 happen, so will continue to use a power pack unless I end up with a horse who shows that is not for him. I have no wish to use moxidectin for anything, so won't unless forced to.

[Auventera Two]

I've never used the Powerpac. Somehow my mare has survived. ;)

Ditto. Never heard of it until I came to COTH. The idea of giving double doses of wormer every day for 5 days just oogs me out. No thanks.

[JB]

Ditto. Never heard of it until I came to COTH. The idea of giving double doses of wormer every day for 5 days just oogs me out. No thanks.

Does it oog you out because you've never heard of it? ;)

It's a well-researched and documented protocol.

Having never heard of it goes to show you that not all vets are up to par on some good deworming protocols. This has been around for a long time, and it highly recommended for many areas of the country.

[mroades]

I love the way my horses look after a powerpac.

[MSP]

The horse.com has two webinars about worming available for viewing. I watched one and they gave two recommended worming schedules. One was 6 way and the other a 4 way. Both included the Lavicidal dose of Fenbendazole, AKA Panacur power Pac!



http://www.thehorse.com/Videos.aspx?tab=webinar

I saw this one...

Strategic Deworming - Heidi A. Brady, PhD, is an associate professor at Texas Tech University


yet to see...

Deworming Your Horse - Craig Reinemeyer, DVM, PhD (East Tennessee Clinical Research) Wendy Vaala, DVM, Dipl. ACVIM, is an Intervet/Schering-Plough Animal Health equine technical services specialist and a former private practitioner.

[webmistress32]

I wonder about the recent rise in worms that are resistant to certain chemicals and the human need to purify and cleanse through chemicals.

coincidence?

[Posting Trot]

Of course it's not a coincidence. But it's also not a coincidence that fewer horses die from parasites.

Costs and benefits. Every single medical intervention (including herbals and non-intervention) includes costs and benefits.

It's silly not to do a Powerpack because "my horse has never needed one" or because "it oogs me out."

Educate yourself and make an informed decision. You may decide not to do a powerpack as a result of that education, but at least you'll know what the risks are (and what the risks are of doing the powerpack as well.)

Personally, I've used Powerpacks and moxidectin (Quest) and never had any problems. Does that mean that no one will ever have any problems? No.

Costs and benefits. Educate yourself.

JMHO.

[EquusMagnificus]

I had never heard of Powerpacs until I came to COTH too but reading about it makes sense.

I never had any use for it but I do have a broodmare right now who scores clean fecal tests but still has this little NQR thing about her. We are most likely going to try a PP, I am at bit at my wits end!

[MSP]

From thehorse.com webinar http://www.thehorse.com/Video.aspx?vID=18

Q: Can you overdo deworming?

A: Yes, the concept that "more is better" is not a sound decision when it comes to deworming. As a matter of fact, many of the studies documenting resistance on a farm have been where there has been a history of very frequent deworming, especially with the same class of dewormer. Deworming programs, including decisions on frequency of use, types and schedules of dewormers, should be based on a complex number of factors such a geographic location, weather, density of horses, age of horses, exposure of those horses to outside untreated horses (for example performance horses on the road), management practices (pasture rotation, etc) and fecal egg counts of animals. It is also important to know if there is a problem of resistance on the farm, which can be determined with pre and post fecal egg count testing (Fecal Egg Count Reduction Tests (FECRT). Based on our studies at Texas Tech, we recommend a 4-way rotation for many farms and ranches. Some conditions may warrant a six way rotation only if needed. The quarterly rotation includes dewormers targeting adult parasites, larval parasites, tapeworms and bots. We believe it is important to consider the range of parasites including ascarids, and not be based only on small strongyle control. Several very recent studies have documented resistance of equine ascarids to the ivermectin class of parasites. This is very alarming due to the serious consequences ascarids can pose to foals. In high numbers, blockage of the gut can occur with fatal results. Because there is no new class of dewormer on the horizon, we believe it is very important to preserve all of the current classes of dewormers, which have different applications in parasite control in the horse. Other researchers suggest even a less frequent schedule of anthelmintic administration based on a targeted approach, where only the heavy egg shedders are given the dewormers. In the targeted approach, the high shedding horses as identified by fecal egg count (FEC) testing are selectively dewormed where as the low shedding horses are not. Further scientific trials and farm testing need to be performed in the immediate future to investigate all approaches to parasite control. The bottom line is that many types of deworming regimens are being proposed. There needs to be further research studies on the effectiveness of these programs throughout the US as well as around the globe.In addition, remember that each farm needs to be considered individually and decisions need to be made based on testing and management information.



Q: Some say that rotational de-worming specialist is an outdated practice, what is the current recommendation based on recent study?

A: I do not believe that rotation is an outdated practice. We showed at Texas Tech that rotation was very efficacious after a resistance problem was verified in a herd of production horses. After resistance to fenbendazole was documented (after experimental use of only FBZ for 18 months without rotation) by extremely poor FECRT and a larval assay, we found that fenbendazole was not effective in this herd, particularly in the young horses where the incidence of small stronglyes (cyathostomes) was very high. We implemented a quarterly rotation of pyrantel pamoate (Strongid, Pfizer) (June) , Ivermectin+Praziquantel (Equimax, Pfizer) (September), fenbendazole larvicidal dose 50 mg/kg BW (Power-Pac, Intervet) (December), and Moxidectin (Quest, Fort Dodge) (March) and had all efficicacies above 95.9%. We are now in the 4th year of monitoring this herd and the control of all types of parasites is excellent. I believe any parasite control program should include frequent monitoring of the herd via FEC and FECR. It is not always evident to the eye of the beholder if there is a parasite problem there.



Q: What are the best drugs/worming regimes to deal with encysted worms.

A: There are two products available that have a label claim to kill encysted small strongyles: Moxidectin and the larvicidal dose of fenbendazole: double dose once-a-day for 5 days (e.g., Panacur Power Pac or Safe Guard Power Dose). Encysted cyathostome larvae hibernate in the mucosa of the horse's large intestines for a variable period of time. Cyathostomes are ingested by the horse from the pasture as infective free-living third stage larvae (L3). These L3 larvae invade and penetrate the mucosa of the horse's large intestines (i.e., the large colon and cecum) where they become "encysted" within a fibrous capsule. Within the cyst the larvae pass through several developmental stages: Early third-stage larvae (EL3) followed by Late third stage larvae (LL3) which then molt to early fourth stage larvae (EL4) and then complete their development to become late fourth stage larvae (LL4). The LL4 emerges from the cyst and re-enters the lumen of intestines and develops into an adult cyathostome capable of laying eggs that then pass back onto the pasture in the manure. Approximately 75% of the encysted Cyathostomes are believed to be present as EL3s. Only larvicidal fenbendazole is labeled to killed ALL 3 stages (EL3, LL3, and LL4) of the hibernating or encysted small strongyles. Moxidectin kills the later stages of encysted cyathosotmes. Ivermectin is effective against the larval forms only after they leave the cyst. Drugs such as pyrantel pamoate (Strongid) are effective against the adult Cyathostomes but not the encysted forms. You are correct when you say that encysted cyathostomes are difficult to diagnose. While the larvae are encysted they are NOT producing eggs. So a fecal egg count may not detect how many hibernating Cyathostomes are present within an individual horse. Most deworming regimens recommend administering a drug effective against encysted Cyathostomes while most of the larvae are hibernating. This is because most of the damage occurs when large numbers of larvae excyst and penetrate back through the intestinal wall. Affected horses may develop colic, diarrhea, weight loss and edema. It is believed that large numbers of Cyathostomes are hibernating in the horse's intestines when conditions are unfavorable for their survival on pasture. In the South this would correspond to hot, dry summers and in the North during the winters. A rule-of-thumb that helps remember when to use a larvicidal treatment is when the grass turns brown (either from high hot temperatures or drought conditions or after freezing temperatures). Climate and weather conditions dictate how and when to deworm rather than simply where you live in the country!

[JB]

No, it oogs me out because I think people go WAY overboard with deworming. We've never done a power pak and our horses have always looked and done just fine. I just can't see any reason to give a horse 10 doses of wormer over 5 days. Sorry, I can't. If you want to, go for it, but I can't imagine ever doing it.

But this isn't about "way overboard" with deworming. This is about getting parasites that nothing but this, and moxidectin, get. If mox is part of your routine, you're covered - no need to do the 5 day double dose.

If you have immaculate parasite control procedures in place, and have for years and years, and can guarantee that new horses coming in have as well, then likely no need.

But the encysted stages can live for YEARS in the horse. If something triggers there emergence, then if the load is big enough, it CAN cause a very serious problem. That is a VERY valid reason to use one of those 2 rotations - mox of 5-day fen.

Otherwise, if a horse has a large enough encysted population, which doesn't emerge all at once (more or less), then you are looking at years of cyclic, lighter emergence and nutrient-stealing.

It's your choice :) Really, it IS your choice :) But there are extremely valid reasons to do ot ;)

[dwblover]

A Powerpac is certainly not going overboard when it is the only way to kill all stages of a terrible encysted strongyle. I have got to find the article that was in Equus about two years ago about a girl who's horse died from them. Her horse was a perfect weight, in work, healthy, young animal who died almost immediatly when thousands of these strongyles hatched and caused him to internally bleed to death. You may think that avoiding such a fate in your horses is overboard, but not I. :no:

[ponyjumper4]

It still takes quite a bit. The safety index for moxidectin is 5, IIRC. You'd really have to TRY to overdose your average horse.

Actually, the lethal dose is 3 unless it has changed to 5, which is why it's not recommended for the young or the small.

Because moxidectin is very good at what it does, I will not use it on a horse unless it has been powerpaked recently and will not use it on anything I suspect might have a heavy worm load.

[RedMare01]

I wonder about the recent rise in worms that are resistant to certain chemicals and the human need to purify and cleanse through chemicals.

coincidence?

Actually this is probably due to not rotating classes of wormers and/or underdosing when worming. What are you suggesting? Not using chemical wormer?

Caitlin

[ThoroughbredFancy]

I Power Pack my horse early Spring. The vets around here recommend it as part of the worming rotation even though we use Quest in Nov/Dec.

[Simkie]

Actually, the lethal dose is 3 unless it has changed to 5, which is why it's not recommended for the young or the small.

Because moxidectin is very good at what it does, I will not use it on a horse unless it has been powerpaked recently and will not use it on anything I suspect might have a heavy worm load.

No, the lethal dose is quite a bit higher.

Here's (http://cat.inist.fr/?aModele=afficheN&cpsidt=13820921) an article citing 5 equines that over dosed from 2 to 10 times the normal dose. Four foals under 4 months and one adult horse. All survived. Quest is not labeled for use in foals under four months.

Here (http://www.wyethah.ca/pdfs/quest_parasite.pps) is a presentation stating 5 times standard dose for several days did not kill any horses and only foals got sick.

There is no LD50 for moxidectin for horses but the MSDS (https://www.accessbutler.com/msdsimages/A0000688.pdf) states the LD50 for rats is 1166 mg/kg.

[webmistress32]

Actually this is probably due to not rotating classes of wormers and/or underdosing when worming.

interesting. have a link to support your theory?

What are you suggesting? Not using chemical wormer?

nope.

[MSP]

Lack of rotation can lead to drug resistant parasites! Lots to learn on that webinar I keep linking to!

http://www.thehorse.com/Video.aspx?vID=18

Q: I have a Friend where i board, who's vet told her it was ok to use Ivermectin all year long as long as once a year she double doses (gives two doses at one time instead of one). She said this was the same as rotating which i don't believe. Doesn't this create resistant worms?

A: There are increasing numbers of reports of drug resistant parasites in all parts of the country as well as from around the world. There are numerous reports of round worms becoming resistant to ivermectin and moxidectin. Many of these reports come from farms that have used nothing but ivermectin every 60 days for many years. More recently there are reports of small strongyles becoming resistant to ivermectin. No one dewormer should be used exclusively for a prolonged period of time.




And one more

Q: We are in our last month of winter right now. We almost lost a 2 y.o pony to Larval cyathosominosis (sp) recently. An unknown event triggered the encysted larvae to all burrow their way out at once, it was touch & go for the little guy. This colt grazes in an 8 acre paddock with 3 other 2 y.o colts and a 20 y.o stallion. I have 20 other horses on the property and none of them have ever suffered from this life threatening issue. Would he have a genetic predisposition to allowing a worm burden to accumulate? I have owned him for 12 months, he is drenched regularly, they are all drenched at the same time with the dose appropriate to their weight. In your experience is the problem likely to recur? It is relatively rare in New Zealand.

A: You are very perceptive when you suggest that the pony may have had a genetic predisposition. We know that genetics plays a role in how resistant or susceptible some horses are to parasites. I would plan on deworming this individual on an annual basis with a dewormer effective against encysted small strongyles..(i.e. larvicidal fenbendazole or moxidectin).

[webmistress32]

more interested in this assertion:

underdosing when worming.

as a cause of chemical resistance.

[MSP]

http://www.thehorse.com/Video.aspx?vID=18

On the video at around 14:17 min. it list reasons for resistance.

1) the continued use of only one class of anthelmintic

2)high frequency of deworming

3) the under dosing of the anthelmintic - by underestimation of the animals weight and by losing product during the administration.

[x-rab]

My older horse was staring to colic on Saturday when it was caught and treated. The Vet recommended doing the PowerPac for 5 days to get the larval stage strongels. I have only had the horse for 2 years and he was not wormed on a regular basis before I bought him so the 2 tubes every other time was not enough to get the larvae. He is a big long horse so it is hard to gage his weight using a weight tape so we were told to give him 3 tubes of Safeguard for 5 days. We are hoping for good results from this.

Needless to say we will be doing this again next year and our other horse will too.

[merrygoround]

more interested in this assertion:

Quote: :underdosing when deworming"Quote

as a cause of chemical resistance.

You should be , it is an accurate staement. I have known people who I have considered knowlegable horse owners, underdose with multiple horses.

BTW I am a moxidectin user. I am also old enough to remember when ivermectin first came on the market, how it reduced the number of colics an equine practitioner saw in a year.

[JB]

My older horse was staring to colic on Saturday when it was caught and treated. The Vet recommended doing the PowerPac for 5 days to get the larval stage strongels. I have only had the horse for 2 years and he was not wormed on a regular basis before I bought him so the 2 tubes every other time was not enough to get the larvae. He is a big long horse so it is hard to gage his weight using a weight tape so we were told to give him 3 tubes of Safeguard for 5 days. We are hoping for good results from this.

Needless to say we will be doing this again next year and our other horse will too.
Do a web search for "calculating horse weight" and you'll find a few formulas to help you get more accurate information than the tape. Don't use anything that doesn't minimally use the girth measurement AND the length measurement :)

more interested in this assertion:

as a cause of chemical resistance.
It's super easy, actually, to search the web for scientific articles on the underdosing issue and resistance :) The same articles often also refer to the use of the wrong chemicals at the wrong times, particularly in conjuction with the "deworm every 8 weeks" mentality. Only ivermectin has an effectiveness of 8 weeks in the body. Moxidectin is 12, praziquantel is around 26, fenbendazole and pyrantel pamoate are in the 5-6 week range.

[Simkie]

Do a web search for "calculating horse weight" and you'll find a few formulas to help you get more accurate information than the tape. Don't use anything that doesn't minimally use the girth measurement AND the length measurement :)

http://ojas.ucok.edu/02/papers/hapgood02.htm

:)


It's super easy, actually, to search the web for scientific articles on the underdosing issue and resistance :) The same articles often also refer to the use of the wrong chemicals at the wrong times, particularly in conjuction with the "deworm every 8 weeks" mentality. Only ivermectin has an effectiveness of 8 weeks in the body. Moxidectin is 12, praziquantel is around 26, fenbendazole and pyrantel pamoate are in the 5-6 week range.

26 for praziquantel?! WOW.

[JB]

http://ojas.ucok.edu/02/papers/hapgood02.htm

:)

That is actually one I have never been able to find in my searches! I SWEAR it's bookmarked now! I wanted to compare it to the one that just does girth and length :D

26 for praziquantel?! WOW.
Ya! :D That's why you really only need to dose for tapes, using prazi, only about twice a year :D

[merrygoround]

http://ojas.ucok.edu/02/papers/hapgood02.htm

:)




26 for praziquantel?! WOW.

Just keep in mind that it is specfic for tapes---only!

[RedMare01]

interesting. have a link to support your theory?


I don't have a specific link, but others seem to have covered that well. :)

FWIW, I Power Pac'd my mare for the first time last year. I've owned her since she was 4 (she is now 14) and she has always been on a consistent deworming schedule, but never had a Power Pac or Quest. I did hers last October and she did just fine with it. No problems at all. Except that she started avoiding me in her stall by the third or fourth day :lol:.

Caitlin

[EqTrainer]

Just keep in mind that it is specfic for tapes---only!

Good point - so no using Equimax only, and just twice a year!

[Linda]

Several years ago, I was on day three of the process with my two horses when my older gelding started showing colic symtoms. This horse had two colic surgeries as a youngster (twists both times) but had been in great health ever since then -thankfully.

We had the vet out, and with some meds, we were able to avert disaster. This was very frightening for all of us and not a whole lot of fun for Andy. I've avoided the powerpac process ever since. It just seemed to me that three days in a row of that much wormer (out of a potential 5 days) was just too hard on his systom.

He turns twenty in a couple of months and is in great shape now!

[JB]

Several years ago, I was on day three of the process with my two horses when my older gelding started showing colic symtoms. This horse had two colic surgeries as a youngster (twists both times) but had been in great health ever since then -thankfully.

We had the vet out, and with some meds, we were able to avert disaster. This was very frightening for all of us and not a whole lot of fun for Andy. I've avoided the powerpac process ever since. It just seemed to me that three days in a row of that much wormer (out of a potential 5 days) was just too hard on his systom.

He turns twenty in a couple of months and is in great shape now!

If you read what I wrote on this thread, and read any of the protocol for the Power Pack, it says that this particular protocol (5 days of double dose fenbendazole) can cause symptoms similar to those of the encysted larve emerging on their own. It does not cause the larve to emerge - it's killing them - but the *symptoms* can look just like it. What is one of those symptoms? Colic type ;) This issue can peak up to about day 14.

So, for horses like that, or if that bothers you even on a horse who's never exhibited that issue, then your ONLY other option is to use moxidectin.

[Linda]

JB
With the colic history that my horse has, not to mention the stress on him (and me) of doing those surgeries not once but twice, I was not about to take any chances that his colic symptoms might not be real...........

[JB]

I did not say the symptoms weren't real. In fact, I gave a very good reason for those symptoms existing. I said that for horses who have that issue with the double dosing of fenbendazole, don't use that for them again.

[gabz]

I do not do a PowerPak on all horses every year. I do one within 6 months of acquiring a new horse. I typically use Quest and Quest+ in my yearly rotation. I also don't wait 8 weeks between each treatment if I've used something other than Quest or Ivermectin.

My QH, who is 22 this year, has been powerpaked at least twice in 11 years. Maybe 3 times. Otherwise he's had Quest 2 times per year. The other horses I've had 1 year and 18 months on the other. They have both had power paks and quest in the past 12 - 18 months. I won't be using a powerpak this year on either of them.