
It depends at what stage Milbemax kills worms?
Some wormers like for example Panacur will kill larval stages, so wormed properly you will never see any worms, especially if you wormed Mum in pregnancy with Panacur.
Puppies once they got to their new homes would be wormed MONTHLY until 6 months and the 3 monthly regime followed after that.
It is primarily puppies and pregnant and nursing bitches that harbour roundworms, because it's all linked to the bitches hormonal and reproductive cycle.
In 20+ years I have never seen worms in my dogs, or puppies, ever.
http://www.noahcompendium.co.uk/Novartis_Animal_Health_UK_Ltd/Milbemax_Tablets_for_small_dogs_and_puppies_Milbemax_Tablets_for_dogs/-51506.htmlMonthly dosage would appear to be a god idea to avoid lungworm picked up from slugs and snails, with pups being more likely to try to eat various things including crunching snails, as well as more likely to sufer from serious consequences should they pick them up..