Fenbendazole (SafeGuard) (Panacur) Side Effects

[carrieb62]

Hi there! Curious to find out if anyone, other then me lol, has experienced unusual side effects in their flock after having used a
fenbendazole based dewormer. I have small bantam chickens. I started using Fenbendazole earlier in 2015 and stopped using it in May of this year. I experienced unusual mortality in my flock along with feathering deformities in some of my birds. I have attached a picture of one of me hens that had such feathering deformity. It was in May of this year I learned not to use Fenbendazole during molt, but I even did more research and found this information...

"Ten African white-backed vultures (Gyps africanus), 3 lappet-faced vultures (Torgos tracheliotus), and 6 marabou storks (Leptoptilos crumeniferus) were routinely treated for gastrointestinal parasitism with fenbendazole administered in the feed at dosages of 47–60 mg/kg for 3 days. Subsequently, all birds became depressed and anorectic. Results of hematologic testing of severely affected birds revealed profound leukopenia. Six white-backed vultures, 1 lappet-faced vulture, and 1 marabou stork died. Gross necropsy findings were minimal other than enlarged livers and spleens. On histologic examination, severe necrotizing enteritis, bacterial hepatitis, and evidence of septicemia were found. The clinical signs and necropsy findings in these birds were consistent with fenbendazole toxicosis. Fenbendazole at published doses can cause immunosuppression and secondary septicemia in some birds. Therefore, benzimidazole anthelmintics should be used with caution in certain avian species, and appropriate, broad-spectrum antibiotic therapy is indicated in suspected cases of benzimidazole toxicosis." http://www.bioone.org/doi/abs/10.1647/1082-6742(2003)017[0016:SFTIVS]2.0.CO;2

I find it peculiarly odd that gross necropsy findings only found enlarged liver & spleens - stunningly similar to what I've been through with my flock. I have since adopted the attitude not to use any fenbendazole products unless a fecal float reveals it's necessary - I do have a veterinarian thank god, but of course I found one after the mortalities, we were stumped - but now we know better Meanwhile, I'm curious to find out if anyone else has experienced unusual side effects from using fenbendazole on their flock - or am I alone in my woes lol.

 

[TwoCrows]

I had heard many years ago that using Safeguard during a molt can cause deformed type feathers, but then recently I read that this was not a true statement being there was no hard core proof. However as with any drug, there are side effects that the drug industry may not be aware of. I use Safeguard exclusively on my flock and oddly enough they ALL have ragged feathers like your top picture here! You may be on to something. Maybe switching to Valbazen wormer is the way to go? However I am sure it also has side effects of some sort.

Great post however and I hope others chime in with more info on this!!

 

[casportpony]

I think that all wormers in the same class as fenbendazole *can* cause feather abnormalities when used during molt. One reference I found says they can cause "fret marks"

This Dr. says feather damage can happen with wormers in the same *family* as fenbendazole (Safeguard): http://www.auspigeonco.com.au/Articles/Race_Form_Part3.html
Quote: This is what fret marks look like:






-Kathy

 

[casportpony]

Here's another interesting abstract:

1.Weber MA, Terrell SP, Neiffer DL, Miller MA, Mangold BJ Bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in five painted storks. J Am Vet Med Assoc 2002 Aug 1;221(3):417-9, 369


Abstract:
Five painted storks were treated with fenbendazole for 5 days for internal parasitism. Four birds died following treatment. Profound heteropenia was a consistent finding in all samples evaluated; additionally, the 1 surviving bird had progressive anemia. Consistent necropsy findings in the 4 birds that died were small intestinal crypt cell necrosis and severe bone marrow depletion and necrosis. Fenbendazole has been associated with bone marrow hypoplasia and enteric damage in mammals and other species of birds. The dosages of fenbendazole used in birds are often substantially higher than those recommended for mammals, which may contribute to bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in birds.

 

[casportpony]

More on the five storks:
http://avmajournals.avma.org/doi/abs/10.2460/javma.2002.221.417?journalCode=javma

And this:
http://www.chelonia.org/articles/medical_misinformation.htm

-Kathy

 

[carrieb62]

I had heard many years ago that using Safeguard during a molt can cause deformed type feathers, but then recently I read that this was not a true statement being there was no hard core proof. However as with any drug, there are side effects that the drug industry may not be aware of. I use Safeguard exclusively on my flock and oddly enough they ALL have ragged feathers like your top picture here! You may be on to something. Maybe switching to Valbazen wormer is the way to go? However I am sure it also has side effects of some sort.

Great post however and I hope others chime in with more info on this!!

Thank you
... I am going to treat all benzimidazole dewormers, as Valbazen is in the same class, the same way I do with Fenbendazole - get a fecal float done to verify what and if any parasitic infections there are. Why treat something that may not even be there in the first place? I'm one of the lucky few that has an avian veterinarian and the veterinarian only charges $12 for fecal float testing. $12 is cheap piece of mind to make sure the right treatment is being applied. When I look at the deformed feathers - I ask myself... what else is going on inside the bird I can't see? It's got to be doing more damage than just deformed feathers. I'm hoping people chime in too, I put this information out here in the hopes that it can help someone, because I know I sure could have used the help way back then, when I was doing the wrong thing on my own, and without a veterinarian. I have one more hen in the process of molting new feathers and will post more comparison pics when she is finished. Since last May I switched back to Wazine, and per veterinarian Ivermectin pour on - and so far everyone has been happier and healthier since the change. And maybe not all breeds are affected the same, my birds are small Old English and mix, and I am working with lavender genetics in my flock which is already extremely sensitive - to everything LOL!

 

[carrieb62]

And thank you casportpony for the valuable information you posted

 

[garp94]

I used it once in my own birds. One [ my dark brahma] was just going into a molt and her feathers were much worse than any pict posted here. Most of her feathers were just vanes until she molted again the following year. Sorry, i didn't shame her by taking any picts, but her name went from "Pants" to "Bare *****"
All my other birds acted normally. I don't remember if anyone else molted at that time.

A friend used it in her flock, and 3 of the dozen birds were lethargic for several days, all recovered.

Neither of us haven't used it since.

I used albendazole when i found worms in my girls early summer. No one was ill and no one was molting.

Just tossing in my limited experience with it.

 

[casportpony]

I'm halfway through my 5th liter of Safeguard, and I have seen no ill effects in any birds.

-Kathy

 

[casportpony]

And thank you casportpony for the valuable information you posted

You're welcome. Definitely looks like it's worth doing some research on the safety of it.

-Kathy