The answer to the first part of the question is yes, cats can eat maggots and they sometimes do when grooming and the answer to the second part is no, cats cannot get maggots from eating flies.
Can a cat eat maggots?
Yes, they can. I can think of a good example. Years ago, when my female cat was dying of kidney disease she spent a lot of time in the backyard, on the grass, snoozing and it is sad to say that a fly deposited maggots in her fur. Perhaps the fly thought that she was dead because she had been static for so long. If she had groomed herself in that area, she might have ingested the maggots. As it happens, I removed them myself. It was a moment which clarified my mind as to whether I should euthanise her or not. No doubt there are other circumstances under which a fly might deposit maggots on a cat such as feces on her fur.
To be clear, maggots are the larvae of adult houseflies. I would have thought that maggots would be a source of protein for a cat if they ate them. We know that maggots are a viable source of protein, trace elements and good fats. My gut feeling is that if a cat ate maggots, it would do them some good.
However, MSD Manual-Veterinary Manual states that when cats consume maggots, “in most cases these maggots pass through the animal undigested”. I’m surprised to read that. Either way, maggots don’t harm cats if they are eaten.
There is a condition called pseudomyiasis which is also referred to as “false strike”. My interpretation is that this describes the situation where maggots are seen in the faeces of domestic cats (because they’ve been eaten) which can give the impression that the cat is suffering from myiasis which is a parasitic infestation of the body of an animal by maggots which grow inside them. This occurs when a fly lays maggots inside an infected wound. Although this is not relevant to answering the questions in the title.
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Can a cat get maggots from eating flies?
The first point to make is that domestic cats are programmed to eat flies because their wild cat ancestor the North African wildcat eats flies. Well, to be more precise they eat insects. For example, in a survey which took place in Eastern Karakum, Turkmenistan, insect remains were found in about 13% of the faeces (scats) of African-Asian Wildcats (North African wildcats). Domestic cats are fascinated with insects, particularly when they are full-time indoor cats because insects trigger their hunting response. It gets their mojo going!
But once a fly has been eaten, it is digested. A cat cannot, therefore, get maggots from eating flies. The flies are food for a domestic cat. Flies carry pathogens in large numbers and therefore you would think that in eating a fly the cat might acquire those pathogens and become sick. However, there appears to be a very low risk. My cat eats flies sometimes and nothing has happened. The author of the website cat-world.com says that her cats eat flies and she does not rush them off to a veterinarian. I wouldn’t worry about it if your cat eats flies. It won’t happen that often anyway.
If someone has a different opinion then please leave a comment and I will work on it.
The study referred to is: On the ecology of Felis Lybica by Y.F. Sapozhenkov 1961.
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