Tapeworm holes
I was interested in learning more about my dog’s tapeworm infection so Google sent me down the worm rabbit hole. She was asymptomatic. We had her stool checked as a requirement for a daycare center. It came back positive for tapeworm and she was given Panacur ™ (Fenbendazole). The handout that the vet gave us talked a lot about Dipylidium caninum, which is a tapeworm that is transmitted by fleas. We didn’t notice any fleas on our dog and she is not scratching excessively. So I talked to the vet and he said she has a different type of tapeworm. It was close to closing time so I didn’t press him for more information. I went down the rabbit hole, I mean wormhole looking for more information. It turns out that Panacur ™ only works for Taenia pisiformis, which is a type of tapeworm with rabbits as an intermediate host.
§ Life cycle
The general life cycle of a tapeworm starts with proglottids or eggs in the feces of the primary host. Proglottids is a segment of the tapeworm that contains a complete set of reproductive organs. The intermediate host gets infected with the eggs or proglottids, for D. caninum that would be fleas and for T. pisiformis it would be rabbits. The primary host gets D. caninum by eating the fleas, not by flea bites. If your dog or cat gets bitten, they would naturally scratch the bite with their teeth and would get the larvae into their mouths. So infants can get D. caninum by putting an infected flea in their mouth. That’s why it’s rare for humans to get D. caninum. For T. pisiformis, it’s a bit more gruesome because the main way to get infected is to bite an infected rabbit because it’s their viscera (internal organs, predominantly in the abdomen) that contains the larvae. The larvae travel from the rabbit’s intestines, into the blood stream, and then to the viscera. I’m still not sure how my dog got infected. I bet Tommy Leung can tell us more about tapeworms.
§ So how does Fenbendazole work?
Fenbendazole is in a class of drugs called anthelmintics, which are drugs that expel worms from the body by killing them or stunning them. In the case of Fenbendazole, it interferes with tubulin polymerization. Microtubules are part of the cytoskeleton. If tubulin polymerization is disrupted, the cells essentially dissolve/collapse.
More information and images here: http://goo.gl/qBZc4p
§ About the image:
It might look like a beautiful flower, but this image of the week is more the stuff of nightmares! The picture above shows a dog tapeworm (Taenia pisiformis) taken using a light microscope. The image clearly shows the hooks of the tapeworm on its head (scolex), which it uses (along with four suckers) to attach to the small intestine of canids like dogs and foxes.
The image was taken by Spike Walker. The tapeworm was on a microscope slide, giving it a slightly squashed look. The muscle and other tissue of the tapeworm were stained red, but the hooks (made of chitin) don’t stain. Therefore, Spike used a contrast enhancement technique called Rheinberg illumination, which gives the hooks their bright colours against a blue background. First demonstrated over a hundred years ago by Julius Rheinberg, this involves using coloured filters so a transparent sample can be seen.
Image source: http://goo.gl/hOAAJK
#ScienceSunday
June 29, 2014
Tapeworm life-cycle!!! This takes me right back to school 😀
I can tell you, I turned vegetarian for some time after reading about it, when I was a kid.
June 29, 2014
It doesn’t sound appealing. Being vegetarian sounds like a good idea, although I doubt my dog would agree.
June 29, 2014
Heh it was more squeamishness than anything else. I went through plenty episodes of vegetarianism all through my school biology years – including the first few months of frog dissection :-/
June 29, 2014
Best wishes to your dog to get better, Chad Haney!
June 29, 2014
I love that you went after the knowledge! SoOoo rocks!
Get well puppy. (Ana!)
June 29, 2014
Poor Ana but I’m glad she inspired this fantastic post! Hope she gets better soon 🙂
June 29, 2014
Thanks Buddhini Samarasinghe. She’s getting better.
June 29, 2014
Thanks Sabeena LoBello. Brigitte W. knowledge is power, right?
June 29, 2014
Exactly.
June 29, 2014
Panacur also works for pinworm and a variety of similar species – the “for kittens” liquid version is also useful for treating reptiles, at roughly 0.1ml per 100g (but check with your vet first).
June 29, 2014
Good point Amber Petchey, Panacur does work for other types of worms but only for Taenia pisiformis tape worm. I thought that was interesting. Ana was on Panacur before, when we first got her; she had whipworm.
June 30, 2014
Funny, it was only a few hours ago that I awoke from a dream where I pulled a blue tapeworm out of my throat. It was small, so I took a pic of it with my camera, to show the doctor.
Then, I apparently pulled another tapeworm out of my throat (I don’t remember grabbing this one). This one was red, much longer (and hence more easily visible), and swollen in one part. I also recall seeing a transparent one, but I don’t recall taking the pic. The tapeworms in my dream weren’t nearly as beautiful as the pic above, and it was a single worm as opposed to the anemone look above.
I woke up with a vague urge to check my pics, and that’s when the dream came back to me. I don’t have a clue why I should have dreamed such a dream, but I also vaguely recalling that I suspected I had contracted the worms by drinking homemade Korean liquor–something that I haven’t really done, though I did enjoy some mountain ginseng infused liquor a few weeks back.
June 30, 2014
Thomas Kang that is a single tapeworm head in the picture above.
June 30, 2014
Right, Chad Haney. I did read the text about the image, but what I meant was that the tapeworms in my dream were the single macro line, like a single line of the anemone-looking close-up.
It’s an amazing image, and I can’t recall whether it was Star Wars or Dune (or both) with the giant worm coming out of the earth, but I’m reminded of that as well–mostly by free association, not necessarily because of any close resemblance to the image above.
June 30, 2014
Hope she gets well soon, Chad Haney
June 30, 2014
She’s on the mend, thanks Siromi Samarasinghe
June 30, 2014
Peter Lindelauf she gets preventative heartworm medicine every month. Once you’ve seen what heartworm can do, it’s cruel not to keep your pet on preventative heartworm meds.