I give Jas wormer every 6 months and I use Panacure

Star gets wormed every 3 months.

That is interesting amts what you say about the same procedure for horses, as here in England our vets insist we worm (always using different wormers each time) every 12 weeks for our horses. They are imperative about it because of the high risk of them getting worm infested by eating the grass, and the damage these worms do to our horses, especially the redworm. I've never been particularly bothered about worming any of my dogs apart from in their puppy years, and they have never had them. I do worm, but not on a regular basis for the dogs.

I think its because we have experienced that using the products causes reststances to the worms. Kind of like some antibiotics.
So now we have to take tests and find out excatly what worms they might have and then treat.

Some will buy products from other countries though and treat regardless, but thats obviosly not legal.

I have found some plants can minimize the worms (in horses) and by changing their field areas and give them enough space, I have managed to keep mine at a minimum of worms (nasty word isnt it lol).

Mine get Drontal from the vets every 3 months.

Although neither of my dogs have ever had worms i routinely worm them every 3 months

I think prevention is always better than cure

Star was sick after her last lot of worming tablets after about 2 hours so we went back to the vet. She said that after about 40 minutes if there were any worms present the tablets would have killed them.

They do not linger in the dogs system like other medication. So they do not work at keeping the worms at bay just kill whatever is there at that time.

I worm mine in Spring and late Autumn, they are in fields and woodland a lot, and you can't always see what they pick up.

Thanks guys - the reason I ask is that Loki was wormed by the breeder early in puppy hood but not since - he is now 7 months. I am a great believer in leaving things alone unless there is a problem but Loki has taken to indulging in horse, cow and - most recently - sheep crap - and this has started to worry me. We do frequently check by sight to see if there are worms (ew!) and so far so good, but I'm still not 100% sure.