Join Date: Mar 2010
Location: Ontario, Canada
I did a fair amount of research into this issue a while back when my cats would only eat fish. I determined that there are various issues associated with feeding fish to cats, but you need to sort through them to determine which are relevant and which arenít, depending on the circumstances. I donít recall reading anything about issues with Vitamin K.
Fish is said to be high in phosphorus, potentially leading to urinary tract disorders. That said, the phosphorus levels in fish-flavored Weruva wet foods are about the same as in the chicken-flavored Weruva foods, so that wouldnít be a relevant issue in switching from fish to chicken (or beef) in the case of Weruva.
Fish-flavored foods have also been linked to hyperthyroidism, due to high levels of PBDEís (polybrominated diphenyl ethers), which are about 12 times higher in fish-based foods. PBDEís have been linked to hyperthyroidism (in a study by Janice A. Dye, DVM, Ph.D., of the U. S. Environmental Protection Agency). As a result, an all-fish diet can result in a greater risk of hyper-T when the cat is older.
Once cats get in the habit of eating fish, they will often refuse to eat anything else. I had this problem with my girls. I started feeding them fish, not realizing the potential issues and, after researching the matter, I tried to switch them to other flavors. They had other ideas! Then, the brand of fish-flavored food I was feeding was discontinued and they refused to eat wet food altogether. They would only eat dry. I have finally switched them back to wet (chicken-flavored Weruva). I now donít give them fish, because I donít want to go back to the problems I earlier had with them refusing to eat anything else.
Interestingly, when I was switching one of my girls (Abby) from dry to wet, the only way I managed to convince her to accept the wet was to put some fish Weruva on top of the chicken. But, each day, I reduced the amount of fish I was feeding her, so that by the end of a week, she was only eating chicken. So, if you do want to switch your cats away from fish, you might try putting a bit of fish Weruva on top of the chicken or beef and see if they just keep on eating through the fish into the chicken or beef.
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