I would like your opinion on this....

[dyachei]

from this website, for Jerseyiscutist: http://www.nature.com/ni/journal/v1/n3/full/ni0900_181.html

"Collectively, therefore, protective immunological memory may depend largely on persistent or reencountered antigen that keeps sufficient effector T cells activated and sufficient B cells maturing to become antibody-producing plasma cells that protect offspring against new infections from the outside and protect the host against expanding infections from within."

All I was saying was that some immunity lasts longer than others and according to the professor I'm currently taking the class from, it isn't clear why tetanus only seems to last 10 years and others last longer (yes it may be the nature of the peptide that acts as an antigen that explains the time variation, but there are other reasons too that influence this and it isn't 100% clear - if you don't understand that, I'm sorry, I can't make it clearer). I'm sorry if that was confusing to you, all I was trying to say is that in vivo, it is much harder to understand these things. Like why my titer may be higher than someone else's even though the vaccine was administered at the same time.

Now, I'm not doing research right now or anything, but if you have read studies that say that vaccines may last the entire lifetime, that may very well be true, but I'd personally want to check and double check those sources. As I just mentioned, in vivo, things are different. I'm interested to know if you'd be willing to share these sources.

In my initial response I didn't attack anything you said, so I'm a little surprised if you think I was. I didn't even mean to attack you with the second one. I was pointing out that when people have responded to you with a differing opinion, it went negatively, suggesting to me that you'd rather not have other opinions. I'm sorry if I've offended you by trying to clarify what you asked me to clarify, its not my intent. I'm just using the knowledge that I have and the research I've done.

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[bakaduin]

No I think vaccines are possibly necessary ( I don't say certainly are, because if you know what you're doing and are responsible--as the example I gave above with the guy who doens't vaccinate at all--it may be possible to go without vaccinating, or course rabies is required by law),

There is certainly more than a reasonable chance that the example you gave was not because the dog was immune to those viruses but because he was never challenged by them. I know you said that the vet brought his dog to work but the vet hospital I work with is a very clean environment and we dont have parvo virus just sitting around on the exam tables from infected puppies and what not. The only way you could be sure that dog still had immunity would be by directly challenging him with the pathogen (which is what studies are for).

Like I also said, who do you know that does anesthesia every year like clockwork because they "might" need it but probably not? If anyone, it's not NEAR as many people as those that are vaccinating every year when they don't need it. I mean, I don't go get my dogs put under to clip their toe nails, THAT would not be needed.

We have clients who go under anesthesia once a year, or once every two years because they are extremely prone to tarter and within a years time develop pretty nasty gingivitis, etc. There are plenty of dogs who go there whole life with horrible teeth and live a long time. Others develop heart problems, kidney problems, abscesses, and other problems and dental cleanings are recommended to prevent any of these possibilities. Like vaccinations, the most effective treatment is prevention.

HOw do you KNOW it doesn't last the lifetime? Because I have read info that says it probably does. Do they have a way now to measure memory cells and cell mediated immunity? They DO know that you don't need parvo and distemper every year.

It is only recently that large studies have been completed to show that vaccinations last 3 years. Considering dogs live on average 10-13 years I find it hard to believe that such long and extensive studies have been done to show that vaccinations can last for a lifetime. Who paid for a study that took 10+ years? Surely not the companies who produce the vaccines. While I agree with your premise, that vaccinations are probably being given to much with the yearly schedule, I think that more money and more research must be done on this subject.

If someone else wants to take the chance with their dog not to be one of those 38 out of 10,000 or whatever, then that's you, I'm not saying that's wrong or right, just saying I'm not willing to do that

I think your mistaken on what this study said. Its not saying that 38 out of 10k dogs have SEVERE reactions or DEATH to vaccinations. 38 adverse reactions isnt very much especially when Im sure many were quickly terminated with the use of diphenhydramine

 

[JerseyisCutest]

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[Poke]

Plus, if MOST of those people took care of the teeth to begin with, they wouldn't need the dental cleaning anyway. So I think they are bringing that on themselves. I have a yorkie and they are terrible prone to having problems and I've handled it so far. So IMO, you can't compare the 2.

I don't think it's fair to compare your experience as a pet owner with others', especially since, as someone who is aspiring to be a vet, you've probably spent quite some time looking at proper animal care. In an ideal world, all pet owners would be completely educated, and with the dedication and time to spend on the care that is recommended. However, even with the best client-education a vet can offer, it's just not practical to expect this out of your clients, at least not all the time. To err is human, and you have to allow for that. And, as always, there are some things that are out of our control.

 

[bakaduin]

This was actually NOT clarified to me........I don't see where it was posted WHAT the reaction was. Maybe someone knows. But unless you do, then you can't assume that's what was meant.

Actually I do know since Ive read the Dr. Moore's JAVMA study. From the abstract

"Electronic records from January 1, 2002, through December 31, 2003, were searched for possible VAAEs (nonspecific vaccine reaction, allergic reaction, urticaria, or anaphylaxis) diagnosed within 3 days of vaccine administration."

"4,678 adverse events (38.2/10,000 dogs vaccinated) were associated with administration of 3,439,576 doses of vaccine to 1,226,159 dogs."

So of those 38.2 in every 10k dogs it is including various different types of reaction and not just death as you postulated.

And I still dont' hestitate to say that you know more people getting anesthesia every year as there are people still getting vaccines every year.

Since the anesthesia isnt a good example to you Ive got another. Heartgard has been shown to RARELY have neurological and digestive side effects. Also animals may have an allergic reaction to it. Does this mean we should take our chances and not use regular heartworm treatment because a few dogs may get sick? I mean its certainly possible to never give your dog a heartworm pill and it never contract heartworms but should we take that risk?

 

[StealthDog]

Does this mean we should take our chances and not use regular heartworm treatment because a few dogs may get sick?

But now we know that you shouldn't use Heartguard in dogs that have the MDR-1 gene mutation, and there are other heartworm preventatives that work in these dogs. We don't leave them unprotected, just give them the right preventative.

If there are genetic predispositions to vaccine reactions (or other factors like breed size), why not try to find alternatives that still leave the dogs protected, but without the risks associated with annual vaccination?

The answer to this whole debate is "We need more data!" It will be very interesting to see what we learn in the next ten years or so.

 

[JerseyisCutest]

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[Bill59]

I know of a GSD breeder/schutzhund competitor who now does not vaccinate at all and hasn't had any problems.....

My uncle has smoked 3 packs a day for 30 years and says he's perfectly healthy ... and that's why anecdotal evidence is not scientific evidence.

Has anyone had any luck finding anything about statistics of adult dogs that get distemper or parvo?

Anecdotally these are pretty rare in adults dogs. Actually this relates to the history of vaccinations in dogs, which is important in understanding how we got to where we are today.

Before vaccinations, veterinarians saw a lot of puppies dying from distemper. They rarely saw this in adult dogs because almost all dogs were exposed as puppies and either died or recovered, in which case they had long-lasting immunity.

When the first CDV vaccines became available in the early 1950s, vets used these in puppies only because that was the only population they were used to seeing the disease in. The incidence of puppies dying of distemper stared to decline.

But then vets started noticing something unusual -- they were seeing adult dogs with distemper. The immunity from these early puppy vaccines was not life long. That's when they started recommending booster doses for adult dogs. Why every year? Because the vaccine manufacturers did challenge studies showing immunity at 1 year. Nobody wanted to not follow the label recommendations and risk a terrible disease.

Over time the vaccines were improved but the label continued to recommend yearly boosters because a longer interval required longer challenge studies. These are expensive and frankly the manufacturers had little incentive to decrease the use of their product.

Also as distemper became less of a problem, people started worrying about some of the rare side effects -- the apparent risk:benefit pendulum started to swing. This increased the pressure to see if yearly vaccines were truly necessary and studies started to show that in adult dogs, immunity lasted longer. So the vaccine recommendations started to change.

Realize that as any pendulum swings, it has a tendency to keep going. So now we're starting to see unsubstantiated claims about vaccine risks (seizures, hyperthyroidism) and some folks claiming that even puppies don't need vaccinations (see the above GSD breeder). At first this decreased compliance won't be much problem because of herd immunity -- as long as the vaccination rate is at least 80-85% in a population the chance of disease outbreak is minimal. But if this ever drops lower, we're going to have a problem.

Or what about wolves? I assume they can get it I could be wrong

Yes, wolves are susceptible to the same diseases as domestic dogs.

 

[Bill59]

But now we know that you shouldn't use Heartguard in dogs that have the MDR-1 gene mutation, ...

Even MDR-1 deficient dogs can take ivermectin-based preventatives. MDR-1 deficient dogs usually need to exceed 100 mcg/kg ivermectin before they develop toxicity and the dose in preventatives is about 6 mcg/kg.

 

[StealthDog]

Sorry, good point. I should have stated Ivermectin in general, not Heartgard specifically.

We haven't quite reached the anti-parasitics yet in Pharm...

 

[sofficat]

No I think vaccines are possibly necessary ( I don't say certainly are, because if you know what you're doing and are responsible--as the example I gave above with the guy who doens't vaccinate at all--it may be possible to go without vaccinating, or course rabies is required by law), .

it doesn't really matter if you 'know what you are doing' or not. for ex- parvo can stay in the soil for up to 6 months (some studies have shown longer). dogs need to be walked (minus the tiny tiny population of pee pad dogs). you walk your dog outside (even if in your own yard) and there could be parvo in your soil! you don't know that over the past 6 months there hasn't been a parvo shedding dog poop in your yard. so not vax AT ALL is dumb.
also, at most practices where i have worked, we will generally avoid vax a very old dog (or even just an old dog with low risk). when age is a factor there is a whole new can of worms to open

 

[JerseyisCutest]

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[sofficat]

If there is a chance of anything fatal happening to my dog that would come from something he *doesn't need*, then I'm not going to do it, no matter how small the chance. .

techincally, all your dog NEEDS is food, water and maybe shelter. Your dog doesn't NEED to be neutered/spayed, he doesn't NEED vax ever, he doesn't NEED to go outside of your house (b/c something fatal COULD happen to him). see how that isn't a good statement? if every client had that exact mentality, we wouldn't have ANY clients!

 

[JerseyisCutest]

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[sofficat]

Plus, if MOST of those people took care of the teeth to begin with, they wouldn't need the dental cleaning anyway. So I think they are bringing that on themselves..

what a terrible thing to say. i don't fight with my two cats every night to brush their teeth knowing that maybe 5 times in their life i'll have to sedate them for a dental. so that means i'm a bad pet owner who is KNOWINGLY bringing that upon my pets. if that is truly your opinion, you are going to be in for a shock when you are a doc (btw, i don't if i missed this, but do you work at an animal hsp?)

 

[JerseyisCutest]

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[ri23]

Ah yes, but that is ONE person. This is many dogs.

It doesn't matter how many dogs it was, it's still anecdotal evidence and health decisions shouldn't be based on anecdotal evidence.

Also, other people aren't the only ones that are missing half the points made in previoius posts.

 

[sofficat]

well once again you just cut out half the conversation. This is when I start to get negative, when people miss my point or just lose part of the convo. Someone mentioned people who get dental cleanings every year.......you're admitting it MIGHT be 5 times in their life (considering cats can live to like 17 or 18 easily...). I can totally understand you wouldn't want to catch your cat for that, neither would I but are you feeding something that is causing tartar buildup? Maybe they are just more inclined to getting it......Every cat I have ever owned or known (including friends' cats) have never once needed teeth cleaning, I dunno maybe because we let our cats outside sometimes? I've only ever seen one cat in the 4 hospitals I've been in actually get teeth cleaning,while many many dogs have come through. Maybe b/c people don't want to spend as much money on cats, I dunno. And you would not need to brush EVERY night anyway, that would wear down the teeth..........but yes, I think it's irresponsible if you know there's a good possibility that your dog might get tartar build up and you don't try to at least ATTEMPT to prevent the problem, this is my opinion. YOu can easily teach a dog when it's a puppy to hold still while you brush his teeth. I've done it with older dogs too. The hospitals I've been at have LWAYS ALWAYS recommended people to take care of the teeth in the first place, so I don't think that's OMG outrageous. And yes, I've been around animal clinics quit a bit........so trust me, I won't be in "shock," I promise

ok ok. let's start over (kind of). when you generalize something (see the above "NEED" section) people will take it the wrong way. i realize we are talking about vax, but the whole 'need' thing (to me) was referring to all of vet med, which pushed a button. also the 'bringing it on themselves' seemed really harsh.
about the dental thing- not every client (or most) is going to brush their dogs teeth, even if just once a week. not every puppy is willing to learn to sit there for that- even though ever pup prob can, but clients won't be willing to fight with a strongwilled dog over something they prob don't want to do anyways, (i just think it is unreasonable to expect so much out of every client, heck- i'm happy when they show up! ) on the other hand, dental food/treats is an easy thing to do to help with tarter (like u said), but it still won't completely get rid of it. also, dentals can most certainly be used as preventatives for actual dental dz, so doing dentals is best when the teeth aren't falling out.
um... let's see... and most cats do need dentals. i've done plently of dentals on cats (and i'm going to do them on mine as preventatives). and brushing teeth won't wear them out (do yours?). i think that is it. i like your spunk. it is making this board more interesting

 

[JerseyisCutest]

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[sofficat]

Vets have told me that over brushing (like every day) can wear down the teeth. Maybe that's opinion. And feeding them the RIGHT kind of food and giving the right kind of bones to chew on does wonders for making tartar free teeth.......I've seen the product many many times. My boyfriend actually got a 3 yr old doberman a while back who came to us with completely covered in tartar teeth. I thougth for certain we'd need to get his teeth cleaned. But lo and behold, after 3 days of letting the dog play with toys and chew on bones, the tartar completely disappeared! And I mean they were COVERED too. So that stuff goes a long way, there's not a necessary need to brush at all with most dogs in my opinion if you do other things right. I dunno about cats, I just know that we've never had one nor do I know personally anyone who has needed teeth cleaned (now my yorkie is a different story , she doesn't use her back teeth to chew on anything, so I have to fight with her to brush, but she's only 3.5 lbs--easy to hold down : D )

the dobbie thing is crazy. i wouldn't have believed you if you didn't see it yourself .
keep in mind, though, that microscopic tarter can do a lot of damage. so even if the plaque chunks were removed, the dog will prob still need a dental in the next few years to get rid of the tarter buildup that can't be seen by the eye that causes gum damage. have you seen teeth (or pics) where they look great but the gum right on top of the teeth is red and irritated? that is when it is best to rec. a dental.
this is a great cat dental website, fyi http://www.peteducation.com/article.cfm?cls=1&cat=1390&articleid=516

 

[Bill59]

Is there any research to show what % of wolves may get this?

There's a number of serologic studies on this and the specific numbers vary with region. For example, one study found a prevalence of exposure to CPV is 65% and for CDV 30% in Canadian wolves.

In the 1990s there was a large outbreak of CDV that killed 1/3 of the lions in the Serengeti plane. In the 1980s an epizootic of a related distemper virus killed off close to 20,000 harbor seals in Europe. There was also an epizootic of CDV in African wild dogs.

 

[JerseyisCutest]

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[bakaduin]

Yeah the whole Heartguard thing isn't really a good example either, sorry. There are other heartworm preventatives, I use revolution for example. Don't honestly know if there are other side effects with that, I'd have to research it. I have never read or heard of any bad reactions to it personally, but certainly that doesn't mean it doesn't happen......vaccine reactions on the other hand, I have read (and seen some) lots of, and terrible things happening too--but then again that's what I'm doing my paper about. But a lot of people around here don't use anything because actually getting heartworms is rare, and I just started using revolution. There are vets around here that don't even use preventative.

Like someone above said you seem to not want other opinions and have an answer for everything.

EVERY Heartworm treatment has side effects, heck every MEDICATION has side effects. I used Heartgard as an example but I guess you want me to list them all. Its funny that you said you have to "research" the side effects when they are appropriately labeled on every box. So here ya go straight from Revolutions:

Side effects when using Revolution may include temporary hair loss, loss of appetite, drooling, vomiting, diarrhea, drowsiness, rapid breathing, increased heart rate, and muscle tremors.

And since I know youll next say "Well thats just revolution you could use other HW prevenatives" Ill just beat you to the punch

Interceptor-
Side effects of Interceptor are rare although some animals may exhibit depression, drowsiness, vomiting, loss of appetite, diarrhea, hypersalivation, seizures and weakness.

Sentinel-
Side effects of Sentinel are rare although some animals may exhibit depression, drowsiness, vomiting, itching, hives, loss of appetite, diarrhea, seizures, convulsions, hypersalivation and weakness.

Iverhart-
The side effects of Iverhart Plus are rare at the recommended heartworm prevention dose. Higher doses in dogs may cause tremors, dilated pupils, and loss of body weight or death. Side effects in cats include agitation, loss of appetite, staggering, dilated pupils, tremors, blindness and disorientation.

 

[dyachei]

I can totally understand you wouldn't want to catch your cat for that, neither would I but are you feeding something that is causing tartar buildup? Maybe they are just more inclined to getting it......Every cat I have ever owned or known (including friends' cats) have never once needed teeth cleaning, I dunno maybe because we let our cats outside sometimes? I've only ever seen one cat in the 4 hospitals I've been in actually get teeth cleaning,while many many dogs have come through. Maybe b/c people don't want to spend as much money on cats, I dunno.

This is just wrong. And it isn't cool to say that people aren't willing to care for their cats. I know in the anecdotal case of my cats, they won't eat some foods, even if it would make their teeth healthier - and therefore would want to feed them. They are indoor/outdoor cats too, and both of them needed (yes needed) dentals last year. At the clinic I worked at recently, there were far more than 4 cats in for dentals in the 3 months I was there. Please understand that when you say things like this, it makes other people respond negatively to you.

Now back to the vaccination discussion....

 

[hoodle]

Just to put this out in the fray... I haven't had time to read everyone's posts so if you've mentioned this already, then I'm sorry for being dense.


Whenever people talk about vaccinations - either animal or human - they start moving towards "oh, this disease isn't common any more, so why are we forcing the risks of vaccination when the actual disease risk is minimal?" It all comes down to issues of herd immunity and ethics, I think.

Yes, if every other person around you vaccinates their dogs, and you refuse to vaccinate yours, there's good change your dog will be fine: you'll be riding off the herd immunity factor. This seems ethically wrong to me. Vaccinations need to be seen in a community health-geared way. All medical procedures have risks (adverse reactions), but vaccinations minimize greater risks not only for you (or your pet) but for those around you.

 

[dyachei]

Just to put this out in the fray... I haven't had time to read everyone's posts so if you've mentioned this already, then I'm sorry for being dense.


Whenever people talk about vaccinations - either animal or human - they start moving towards "oh, this disease isn't common any more, so why are we forcing the risks of vaccination when the actual disease risk is minimal?" It all comes down to issues of herd immunity and ethics, I think.

Yes, if every other person around you vaccinates their dogs, and you refuse to vaccinate yours, there's good change your dog will be fine: you'll be riding off the herd immunity factor. This seems ethically wrong to me. Vaccinations need to be seen in a community health-geared way. All medical procedures have risks (adverse reactions), but vaccinations minimize greater risks not only for you (or your pet) but for those around you.

Well put.

 

[JerseyisCutest]

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[sofficat]

it's a funny thing........I don't recall saying or implying that people aren't willing to care for their cats, if sofficat (sp?) shells out that much money that often to have their teeth cleaned, I certainly believe she is willing to care for hers, and a heck of a lot more than most people...........hmmmm guess you didn't catch the point? which wasn't really referring to cats........anyway........

Actually, on my box of Revolution (which I just checked to be certain) it does NOT give side effects. As I also already mentioned, I don't know tons about heartworm preventatives because I haven't dealt with them very long. Heartworm is super super rare here........my dogs aren't even outside without me around so the chance they'd be bitten is practically zero, but just in case I have started giving them something. I never mentioned that I thought preventatives didn't have side effects either so I don't know why you are attacking me on this. There also isn't a way for me to test to see if my dogs are immune to heartworm, as there is for parvo..distemper.....etc. sooooooo I'm not quite sure how we can compare them, why you are discussing this, or why you went to the trouble of listing all that? I dunno, but next time you post could you discuss vaccinations in some way please? I'm not writing a paper on heartworm.........maybe that'll be next

before people start attacking you....
where are your from that heartworms basically don't exist? also- big point-
heartworms are passed from mosquitoes, so do you really think that you would see one bite your dog? you might want to rephrase that. a dental for cats every 5 years (from where i am from/worked) is not an extreme concept, just wanted to let that be known.
the hw prevention person is just giving you examples to prove his point, that's all. no need for us to get upset (and talking from experience)

 

[JerseyisCutest]

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[bakaduin]

before people start attacking you....
where are your from that heartworms basically don't exist? also- big point-
heartworms are passed from mosquitoes, so do you really think that you would see one bite your dog? you might want to rephrase that. a dental for cats every 5 years (from where i am from/worked) is not an extreme concept, just wanted to let that be known.
the hw prevention person is just giving you examples to prove his point, that's all. no need for us to get upset (and talking from experience)

Thanks sofficat =)! I was justs trying to prove the point that just because something may cause side effects in a small percentage of animals (i.e. Vaccines or Heartworm prevention) that doesn't mean it shouldnt be used. It was in relation to your post here....

And frankly, even if it's 38 dogs per 100,000, that's still 38 dogs too many for me when this is something that probably doesn't need done as often as it is. How do I know my dogs won't be one of those 38?

Basically I will reiterate the point I made in the beginning. I dont disagree that we may be over-vaccinating but I think we need to see a lot more research on the actual length a vaccine lasts before I go to all the trouble.

In the IDEAL world we would vaccinate and take titers two weeks later to see if the animal seroconverted.

 

[JerseyisCutest]

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[ri23]

Is heartworm really not that prevalent in WV? In Ohio we test yearly and we recommend year round heartworm prevention and though not common, we do see cases here and there.

 

[JerseyisCutest]

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[nyanko]

no not really.........not that it doesn't happen.......but it's rare enough some vets dont even mention it, of course I'm not saying that's a right or wrong thing to do......or that I think it's okay or anything. As a side note, totally not with this topic, I know of very few people who have ever even been bit, and then it's just once.

1-6 cases per clinic per year and that's what was reported for 2004. I would imagine that's because of the sparsely populated areas, as clinics in some counties show an average as high as 14.5 cases per year. (source: http://heartgard.us.merial.com/whyheartgard/why_problemareas.asp# )

Granted, that's much lower than the number at the clinic where I worked in Orlando, but it's common enough that every dog should be on heartworm preventative for at least 9 months out of the year, if not all year. I don't believe for one second that in ANY case the risks outweigh the benefits of heartworm preventative. If it's got the gene making it susceptible to ivermectin toxicity (and Heartgard is even safe for these dogs as already mentioned) there are other alternatives and I would never step foot in any vet's office who didn't recommend heartworm preventative to each and every dog to walk through their door.

You know, not to personally attack you, but I've seen you spread some pretty bad misinformation on here sometimes and it kind of worries me as we are all future veterinary professionals.

 

[bakaduin]

1-6 cases per clinic per year and that's what was reported for 2004. I would imagine that's because of the sparsely populated areas, as clinics in some counties show an average as high as 14.5 cases per year. (source: http://heartgard.us.merial.com/whyheartgard/why_problemareas.asp# )

Granted, that's much lower than the number at the clinic where I worked in Orlando, but it's common enough that every dog should be on heartworm preventative for at least 9 months out of the year, if not all year. I don't believe for one second that in ANY case the risks outweigh the benefits of heartworm preventative. If it's got the gene making it susceptible to ivermectin toxicity (and Heartgard is even safe for these dogs as already mentioned) there are other alternatives and I would never step foot in any vet's office who didn't recommend heartworm preventative to each and every dog to walk through their door.

You know, not to personally attack you, but I've seen you spread some pretty bad misinformation on here sometimes and it kind of worries me as we are all future veterinary professionals.

Wonderful and insightful post.

 

[JerseyisCutest]

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[JerseyisCutest]

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[Kara31191]

The clinic I work at does one year rabies followed by 3 year rabies thereafter if you come in by the date of the one year rabies. We also do three year distempers (again not the first one). Bordetella is a one year vaccine. Lyme is a one year vaccine (in New England). We don't do Lepto due to high probability of reactions and short immunity offered by vaccination.

I believe the same thing is done at the clinic I work for. I know that my own dogs vacinations were "staggered" so to speak. We give my dogs lyme every year and I think Bordetella, and the rabies and distemper are staggered.

This is an interesting thread.

 

[WhtsThFrequency]

Interesting discussion...I very heartened to see more vet students having heard of Dr. Dodds....


If it's got the gene making it susceptible to ivermectin toxicity (and Heartgard is even safe for these dogs as already mentioned)

A bit OT but I am glad people realize this now...the ivermectin problems in collies only occur when people use high-concentration ivermectins (someone buys a high-conc lot to dose their cattle, and decide to give their dog some too, and try to scale it down to dog doses) which only increases chances of mistakes and overdoses. The amount of ivermectin in commercial heartworm preventative is not enough to cause damage even to a collie with the mutant gene.