Is there an intestinal parasite which can be found in dogs with the overall size and consistency of a used condom, and lengthwise grooves not unlike those found in the throat of a blue whale (for a crude comparison)? No segmentation.

The dog in question has not, in fact, eaten any condoms, having both no history of pica and no access to them.

He was dewormed two days ago. Incidentally, the dewormer made both dogs ill this time, with one suffering from diarrhea devolving into shitting blood and not much else, and the dog in question having bloody mucoid stool yesterday as well as food refusal.

It's a holiday weekend, so the local vet is closed, and the e-vet is 50km away but I can't drive because I'm badly epileptic. They'll be going to the vet tomorrow, though.