Question on Safe-Guard vs Aquasol product info

[NestingMillenial]

I am looking at Safeguard right now and I have some questions when I compare the dosage often given here and the ones for Aquasol (the approved version for chickens)

Aquasol is 200mg fenbendazole/ml of product (20%)
-> recommendations from the product bulletin and the US National Lib. of Med. both say 0.454mg of fenbendazole/lb of BW (aggregated across the flock, so I suppose we have to assume bigger chickens will drink more) for 5 days
-> at 20%, this would be 0.00227mL of product/lb, which might be a challenge to administer on small flocks
-> this is approved with no withdrawal period for eggs

SafeGuard goat is 10% = 100mg of fenbendazole/ml of product
-> recommendations I have seen most often here say 0.23ml of product/lb of BW
-> at 10%, this is 23mg fenbendazole/lb of BW
-> I often see a 15 days egg withdrawal period being recommended

It's not a small difference!! Can we really treat with that little over 5 days? Could I just give a smaller amount of the goat 10% product and enjoy no egg withdrawal? What am I missing, this seems too good to be true!

Edit: I am seeing on the EU Medicines Agency that there is no egg withdrawal recommendation for Aquasol even when used at twice that dosage (=1mg of fenbendazole/lb, which would amount to 0.01ml of SafeGuard 10% /lb of BW to get that dosage)

 

[casportpony]

The gapeworm dose does not need to be that high.

This is what one of my books say:

 

[casportpony]

What book is this?

https://www.amazon.com/Veterinary-P...15b-45e2-8a98-533eeb1b7bc1&pd_rd_i=0813824192

 

[casportpony]

If you give hens the 1 mg/kg dose, the fenbendazole residue in the eggs does not exceed the max fenbendazole residue allowed. However, other worms, like capillary worms, need more aggressive treatment, and with those amounts, there is too much fenbendazole residue in the eggs.

Does that make sense?

 

[Razzlefrazzle]

On a side note since this seems to be the first time you are deworming, safeguard/fenbendazole has a warning against using during molt as it can cause feather damage. I somehow missed this warning despite doing quite a bit of research my first time around.... I know a lot of people on here say they've never had issues with it, but one of my girls hasn't had normal tailfeathers since that first ill-timed safeguard deworming, so I thought I'd throw it out there in case it could be an issue for you.

 

[Kiki]

Interesting!
The European bulleting I linked says that "A further field study involved chickens bred for laying and broiler breeders (chickens producing parent stock for chickens bred for meat), infected with Capillaria worms. Panacur AquaSol treatment at 2 mg/kg for 5 days reduced worm counts by 100%." but I did not find mention of the gapeworms anywhere, so I have no idea for those!

 

[casportpony]

Also, horses, goats and cows should all receive 2.3mg of fenbendazole/lb of body weight... (so 0.023ml of the 10% product / lb of body weight)... why are chickens at 10 times this dosage? Did we just come up with this to be safe and make sure we kill it all in there, or is there another reason why they should be given that much?

sources:
Horse and cows: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=391b94ab-535c-4a8c-94d1-d3c5de11f81b
Goats: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=89567dad-e2d5-4b7b-9e6e-c35668c3c2fa

It's not made up, it's because they have a faster metabolism, and there are many proper veterinary references to back this up.

 

[casportpony]

Panacur might be the one making it in EU, not sure, but the concentration, dosage recommendation and administration were exactly the same (see the link to the EU web page). Panacur also exists as a horse paste that i have seen used for chickens (see: https://the-chicken-chick.com/control-treatment-of-worms-in-chickens)

I would stop thinking about the water-soluble one and get the liquid for goats. The water-soluble is close to $300 a liter and has a shelf life of 6 months after being opened.

 

[casportpony]

Yes, and this is accounted for in the number of mg/lb of body weight I am citing (see the first post for the calculations!)

Hold on, I am trying to put something together that explains this better.

 

[NestingMillenial]

If you give hens the 1 mg/kg dose, the fenbendazole residue in the eggs does not exceed the max fenbendazole residue allowed. However, other worms, like capillary worms, need more aggressive treatment, and with those amounts, there is too much fenbendazole residue in the eggs.

Does that make sense?

It does, but with a little bit of qualification: the EU Medicines Agency finds the eggs still safe to eat with no withdrawal when using 2mg fenbendazole/lb of bodyweight, which is seen to 100% get rid of capillary worms in 5 days.

So while it makes sense, it would have to be for other worms: is that still holding? (I wonder whether those newer studies (the report cited earlier is from 2016 for example) might mean that we could update our recommendations or if we should still assume that other worms like maybe gapeworms like Eggcessive mentioned, still necessitate a higher dose)