Why should one not feed fish to their cats? Or cat foods that contain fish? :o I give my cats tuna wetfood and I give them a teaspoon of salmon oil every week since I've heard that it makes wonders to their coat
There are several reasons.
Fish based foods may contribute to feline hyperthyroidism.
Fish used in cat food is often heavy in mercury. (1, 2, 3) Â Mercury accumulates in the kidneys, and urinary tract disorders are extremely common in cats.
A tuna fish cat food diet was linked to behavioral changes, and neurological changes.
Fish used in cat food is often high in other contaminants such as PCB and pesticides, chemicals also linked to health problems, including hyperthyroidism. (1, 2, 3)
Along with beef and lamb, fish is the most common animal protein that cats are allergic to.
Fish-based foods tend to be higher in phosphorus and ash, causing urinary tract problems in cats.
Some fish used in cat food may contain thiaminase, which can cause problems in absorbing thiamin (B1). However, thiaminase is destroyed by cooking.
Finally, cats will often get picky on a fish diet, and refuse to eat other, healthier protein sources. However, safe, low contamination fish may be helpful in transitioning a cat from one diet (such as dry) to a healthier diet (such as canned).Â
If you do feed salmon oil, be sure it is sourced from wild salmon and not farmed salmon (which is much higher in contaminants). However, a cat on a proper, wet, high-protein, grain-free/low carb diet should have an amazing coat, without fish. Because fish is very allergenic, some cats may have coat issues when fed fish.