Why fish is dangerous for cats

Jean Hofve, DVM june 2005
Source:
www.littlebigcat.com

A lot of cats love fish, but it's really not a good idea to feed your cat very much of it! Why not?

  • The fish used in canned foods usually includes bones. This greatly increases the ash content of the food. Many cats are sensitive or even allergic to fish; in practice I have seen quite a few develop urinary tract infections or even blockages if they eat very much of it.
  • Predatory fish at the top of the food chain, such as tuna and salmon, may contain very elevated levels of heavy metals (including mercury) as well as PCBs and other toxins.
  • Fish tends to be "addictive" to cats. They love it, and will often stage a "hunger strike" by refusing their regular food in favor of fish, which should be reserved as a very occasional and special treat; absolutely no more than once a week, and even then in very small amounts only.
  • There is a known link between the feeding of fish-type cat foods and the development of hyperthyroidism in older cats.
  • The vast majority of salmon in the U.S. comes from farm-raised fish. These unfortunate animals are kept in overcrowded pens in polluted coastal waters. They're fed anti-fungals, antibiotics, and dyes to make their flesh that salmon color--otherwise it would be gray. These contaminants will then be in any food made with farmed fish. Salmon who escape their pens (and they do) outcompete and interbreed with wild salmon, as well as transmit diseases. It is feared that they may ultimately decimate the wild population in the Atlantic. The meat is toxic and the industry is environmentally destructive--need we say more?

In general, the small amounts of "fish meal" included as a flavoring and/or source of oil in cat foods are generally not a problem, but fish should not be a mainstay of a cat's diet.