My bitch is now 33 days pregant, i've scanned her and she carrying 4 pups,  we went for our check up at the vets yesterday and everything is fine, temp and heartbeat.  My vet advised that i should start worming my bitch on day 40 then everyday till after pups are born, i had already ordered my Panacar paste ready for this.  However, i've been told by other breeders that they would not recommend worming while pregnant.  what's your thoughts?

This has come up many times before if you search back through earlier posts.  You have to do what you feel comfortable with.  Personally, I don't give a bitch any chemicals whilst pregnant.  I worm when she first comes into season and then I worm pups and mum at 3wks. 

If the mother dog was a stray or rescue, or if she had earlier in her life had a heavy worm burden, I might worm during pregnancy - but for the majority of bitches who are wormed relatively frequently in their lives anyway, I don't believe they carry enough encysted eggs to make a difference and I'd prefer not to give chemicals during pregnancy.

Other breeders on this site, looking at earlier posts, have no probs with this.

thank you.  she's never had worms and i wormed her the week before mating,

All bitches are infected with roundworm larvae. These lie hidden and dormant within the body of the bitch and become active during pregnancy, infecting the pups while they are still in the womb. In addition, once the puppies are born, further worm infection comes from the milk when they are suckling. Ideally, starting from day 40 of the pregnancy, bitches need to be wormed every day until 2 days after whelping. I use Panacur 10%  (1/4 of the normal dose)on my girls and touch wood have never experienced any problems with mums or pups

I 100% agree with lleonder.  I have used Panacur 10% liquid for more pregnant bitches than I can count.  I start them at day 40 until 2 days post whelping.  It is only a quarter of an adult dose as lleonder points out.  And it is important to remember that the manufacturers have trialled this at many times the recommended dose with no problems whatsoever.  Indeed, for a very long time it was the only wormer recommended for pregnant bitches.

I worm my bitches with Drontal prior to mating. But bear in mind this will not kill the encysted worms.  It is actually pregnancy hormones that awaken these dormant worms, so all the worming in the world, prior to mating, will not help at all.  I then worm pups at 14 days, they get a small dose for 3 days.  Mum is done at the same time, but only at day one, as she is then given the normal adult dose.  All are done every 14 days thereafter. 

Using Panacur during pregnancy ensures that pups don't have a worm burden in the womb.  All they have to do is thrive. 

The Panacur 10% data sheet itself states:

"Use during pregnancy, lactation or lay:

The product can be used in pregnant bitches. As teratogenic effects in dogs and cats cannot be completely ruled out in very rare cases, the treatment in the first two trimesters of pregnancy should be based on the benefit-risk evaluation by the responsible veterinary surgeon."

The idea that 'teratogenic effects' cannot be completely ruled out, is enough for me not to use this during pregnancy - no matter if it's only 'very rare cases'(!).  I've seen no evidence of worms in pups or mum, including after the first worming at 3wks.

(A teratogen is an agent that can disturb the development of the embryo or fetus. Teratogens halt the pregnancy or produce a congenital malformation (a birth defect).)

http://www.noahcompendium.co.uk/?id=-455815

We wormed our bitches just BEFORE being mated and then at 2 weeks post-birth, when the puppies were first wormed.

I hesitate to say because what I did back then, may well not what people do these days

> In addition, once the puppies are born, further worm infection comes from the milk when they are suckling

.... to say nothing of the fact that mum is cleaning up after the pups empty so if they are carrying any kind of worm-load, she'd be affected!

> If the mother dog was a stray or rescue, or if she had earlier in her life had a heavy worm burden, I might worm during pregnancy

Whether or not a bitch has previously had a heavy worm burden is totally irrelevant.  The worms during pregnancy are still going to be there.  Pregnancy hormones trigger the encysted worms.  So it is impossible for a none pregnant bitch to have them.

And if a bitch is wormed while pregnant her pups aren't going to have worms, so she has no problems picking anything up while cleaning them.

>Whether or not a bitch has previously had a heavy worm burden is totally irrelevant. 

No, it's not actually.  If a bitch herself has been raised by a breeder who wormed her from the age of 3wks and she has been regularly wormed in her life, there hasn't been an opportunity for any worms to become encysted.  (If there are any, they are so few as to be no problem and being wormed at 3wks will remove them from both pups and mum.) 

If a dog has previously had a heavy worm burden at some point in her life, she will carry encysted worms as a result of that and may well pass them to puppies during pregnancy. 

Evidence:  Experience of many pregnant rescue dogs as compared to many well-bred and raised dogs and resulting pups - and what came out the other end. 

If a bitch and pups are all wormed at 3wks at the same time, nothing is going to get passed between them when the dam cleans the pups.

Mamabas, that's what we do as well.  Incidentally, Panacur (which is called Safeguard in the US) is not licensed to be used during pregnancy in the US.  Strange how, therefore, all US litters must be being born with worms.... those poor US breeders!  (Of course they are not...!)

Interestingly the datasheet for finnish version of panacur only recommends the UK worming routine if the bitch is "at risk" Group e.g. unknown history or had issues in previous pregnancy/whelps... I only realised this when I bought some for a bitch that was in Finland at the beginning part of the pregnancy and happened to read the datasheet to check the amount.

That's very interesting Noora - and is basically what I'm saying.  (If we class 'at risk' as being stray or not wormed frequently or having previously had a heavy worm burden.)

I have used Panacur 10% liquid for 8 generations of my bitches in pregnancy.

This gives pups a headstart with 98% reduction in worm burden.

Onetwothreefour,  Most US dogs will be on regular heartworm medication,  which will also clear roundworms,  so are in effect being wormed much more frequently than ours,  at monthly intervals,  including in pregnancy.

Like I said - different people do different things.  Personally, I think the risks of giving any chemicals during pregnancy far outweigh the risk of not worming if a bitch has not previously carried a heavy worm burden and has been regularly wormed during her life.