Pictures of Flea Cocoons

picture of flea cocoons

Marcelo de Campos Pereira

Img 1 Cat flea cocoons camouflaged with environmental debris (sand).

image of a flea pupae in its cocoon

Auguste Le Roux

Img 2 A cat flea cocoon torn open to reveal the pupa inside.

picture of cat flea larvae forming a cocoon

Cat Flea Biology

Img 3 A cat flea larva forming its cocoon with silk is excreted from its labial (salivary) glands.

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  • Mary Schindler June 13, 2017, 5:47 am

    Hi, I had a Vet recommend sprinkling Brewers Yeast on my cats food to ward off fleas. I also recently read that Nutritional Yeast was similar to Brewers Yeast but not quite as bitter. Have you heard of this? And how much should be used? I saw some 1000 mg tablets of the Brewers Yeast that could be crushed up and added to her food. Also does adding a tsp of Apple Cider vinegar to her water repel fleas as well? Just trying to keep it more natural than chemical. Thanks in advance for you help.

    • Adam Retzer June 13, 2017, 4:46 pm

      I’ve never read anything about Brewer’s yeast repelling fleas. In fact, in laboratory studies, flea larvae are often fed Brewers’ yeast to raise them. So, that doesn’t make a lot of sense to me. I’d be interested in seeing the source from which your vet is basing their recommendation, as I’ve read most of the literature.

      There’s also no evidence that apple cider vinegar repels fleas. Some websites say it does, but these are unfounded tips from what I can tell. I’ve searched extensively for reliable sources stating that vinegar repels or kills fleas and can’t find any. I’ve written a page on it here.

      Perhaps these methods do work, as there are some anecdotal claims. But I can’t find any scientific references, and that’s the focus of this site.