Link between fish-based foods and chronic kidney disease in domestic cats?

Can fish based cat foods contribute or cause CKD?

There is a scientific study published online on the nature.com website which concludes that there may be a link between fish flavoured (fish-based) foods and chronic kidney disease (CKD) but the link is tenuous. It is however worth flagging so cat owners know about it. More work needs to be done.

My understanding is that the study says the following:

Domestic cats are fed more fish-based foods that dogs
Fish-based foods have a higher arsenic content although this is primarily non-toxic arsenic
Arsenic in tissues and urine is present in higher amounts in cats compared to dogs.
The arsenic content is a pro-oxidant metallic element which lowers the concentration of antioxidant minerals such as copper and zinc and minerals which protect the kidney such as rubidium and strontium.
As I understand it this lowering of antioxidant minerals can lead to chronic interstitial nephritis (CIN) which is the most common renal lesion and a cause of chronic kidney disease.
CIN was present in 51% of cats compared to 15% of dogs. CIN is absent in Scottish wildcats.

That is an essential breakdown. It is very technical and a potential warning to cat guardians, no more.

If you are so predisposed i.e. scientifically minded, you can read the study by clicking on this link (sometimes links to other website break and if that has happened I apologise but I have no control over it). I don’t want to write extensively about this study because it is very technically and I am liable to make a mistake.

Comments

Link between fish-based foods and chronic kidney disease in domestic cats? — 2 Comments

Jon Todd on July 22, 2022 at 11:44 pm said:
I read your article on the possible link between consumption of fish in the diet and feline chronic kidney disease. I had a cat die of that in 1998. My present cat loves fish and seafood. What caught my attention was the can in the photo accompanying the article. I recognized it despite the brand being obscured. I used to feed my cat that same brand and flavor a lot. I particlarly noticed that Scottish Wildcats are free of kidney disease. At his last check-up, my cat’s veterinarian told me that, unusually for an 18 year old cat, his kidneys were completely healthy like a very much younger cat. He loves fish and I feed him a lot of it. Other than smoked salmon-which he doesn’t like, he prefers fish to any other meal. He’s a Pixie-Bob and they are supposed to have a few Bobcat genes as one of the original cats from whom the line was bred was supposed to have been the product of an encounter between a domestic cat and a Bobcat, and I was wondering if possible that my cat’s kidneys were being protected by some genetic inheritance from Bobcats? I know Bobcats are not Scottish Wildcats, but Bobcats are comparatively long-lived for felids, and as far as I know, which is not very far, their longevity might possibly be due in part to a freedom from kidney disease akin to that enjoyed by Scottish Wildcats. I know Bobcats were not part of the study you were writing about, but given their relative longevity, perhaps some researcher in future might want to investigate if Bobcats have a similar immunity to this particular kidney disese.
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- Michael Broad on July 23, 2022 at 12:52 pm said:
  That is an interesting thought about bobcat genes protecting your domestic cat from kidney disease. However, despite the fact that it is a well-reasoned argument I think that you will find that it is untrue because all the reports about the Pixie bob state that there are no wild cat genes in this purebred cat breed. They are selectively bred to look a bit like a bobcat but there has been no mating between bobcats and domestic cats in this instance.
  My guess is that your cat was particularly robust in respect of kidney disease. I’m going to guess that this individual cat had a genetic makeup which helped to protect them against kidney disease. Some purebred cats are predisposed to it and some aren’t. There is a variability there. Certainly, your experience flies in the face of the article that you refer to which states that there might be an increase in the possibility of contracting kidney disease if a cat eats more fish-based foods. That was, however, a very tenuous report it seems to me.
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