"So, naturalists observe, a flea has smaller fleas that on him prey; and these have smaller still to bite ’em; and so proceed ad infinitum."
- Jonathan Swift

April 28, 2010

April 28 - Melophagus ovinus

What do you call a fly that doesn't fly? In this case, you call it a sheep ked. Melophagus ovinus is a very common ectoparasite of sheep. The adults feed off the blood of the sheep, hiding easily in the wool. The females will give "birth" to well-developed larvae, which actually feed off "milk" that is secreted by specialized glands of their mother. They then pupate, cementing the pupal case to the wool. The pupal stage will last for about a month and this stage is unfortunately resistant to any insecticides, making keds difficult to eradicate if the population is firmly established. Keds are distressing to the sheep and as they attempt to itch them, they will rub off or thin out their wool. thus pose economic threats to shepherds who find themselves struck with these pesky insects.


  1. Great blog, I'm a regular reader. But I think you mean "as they attempt to scratch them", not "itch" :)

  2. Yes, I suppose that's a better way to say that!