No problem about the delay and no apologies necessary!
Yes, those pictures were pretty awful, weren't they but when it comes to identifying parasites in a dog's stool, a picture is really worth a thousand words, as they say.
It sounds like Lil Andy may be suffering from a recurrent infection from tapeworms...these are flat, segmented worms and the segments dry up after a while and can look like dried pieces of coconut or very small grains of rice. (LINK
These worms always require what's called an intermediate host which in most cases is going to be fleas. Until or if the flea population is controlled, some dogs will continue to have problems with tapeworms.
These worms are not transmitted from dog to dog or even from a cat's feces (or a cat) to a dog. This intermediate host is always required life cycle to be completed.
Most dogs only require one treatment to eliminate this parasite but some dogs do tend to be overly sensitive to recurrent infections...perhaps because of a reduced or immature immune system?
I usually use Praziquantel which comes as an injection or pills; I suspect this is what your vet dispensed. If I suspect a resistant tapeworm infection (which does occasionally happen), then I'll worm with the drug at twice the recommended dose ( 10 mg/kg and repeat in 2 weeks). I wouldn't worm all of the other dogs though at this higher dose; I'd just worm him.
Since Lil Andy appears to have consistent problems with these worms, you might want to consider giving him monthly Iverhart Max (LINK
). Not only will this product protect against heartworm disease, but it contains Praziquantel which should help prevent reinfection.
I hope this helps and that this problem can be resolved satisfactorily...I know this is your fervent wish as well! Deb