Fish as a secondary ingredient

tdonline

TCS Member
Thread starter
Super Cat
Joined
Mar 20, 2009
Messages
707
Purraise
44
My cats are eschewing canned Wellness and Evo for Friskies nowadays.  Due to medication and behavioral situations, I'm going with the flow.  I figure it's better to feed Friskies than for them to go on a hunger strike or feed them kibble-their true love.

They love Poultry Platter.  I was able to upgrade them to sometimes eating Fancy Feast Classic chicken.  I am also able to sneak in a bit of the grain-free Wellness and Evo to augment.  My concern is Friskies and FF have fish as secondary ingredients in their 'meat' flavors.  I only discovered yesterday that Friskies Mixed Grill and Country Style doesn't list fish as an ingredient.  I'm hoping to transition them eating those flavors.  Checking online there seems to be a number of FF Classics flavor without fish also.  I'll check those out as well.  A couple of minor complications is that my cats can't handle red meat so we usually stick with poultry.  And from poultry, they prefer chicken alone.  It's clear they will eat less if I feed them the same brand but it's chicken and liver rather than just chicken for example.  They seem pretty happy with Friskies in general though.  Perhaps it really is kitty krack.

If fish is a secondary ingredient, is it likely to cause any issues?  I'm concerned my cats eating a tiny but daily portion of fish could eventually cause urinary problems.  
 

vball91

TCS Member
Veteran
Joined
Jan 14, 2013
Messages
3,853
Purraise
252
Location
CO, USA
The current research shows that there really isn't a link between higher magnesium levels from fish and urinary problems like once thought. There are other reasons why a primarily fish based diet isn't good though. As long as fish is lower down on the ingredients list, I would not worry too much about it, especially since you are mixing in other foods that don't have fish. It is definitely better than a hunger strike or kibble. :)
 

mayadot

TCS Member
Young Cat
Joined
Jul 16, 2012
Messages
93
Purraise
44
Location
western US
I am also having difficulty with food selections and one that I am considering has fish oil listed as ingredient (not one of the first 5 ingredients but it is there). I have just read some studies regarding a link between fish and hyperthyroidism in cats, so I was also concerned about this. Do you have information about that, @vball91?
 

vball91

TCS Member
Veteran
Joined
Jan 14, 2013
Messages
3,853
Purraise
252
Location
CO, USA
I don't think that fish oil has the same issues as fish. A quality fish oil provides the good omega 3s without the other issues. Haven't heard of the link between fish and hyperthyroidism in cats although I know there is one between soy and hyperthyroidism.
 

mayadot

TCS Member
Young Cat
Joined
Jul 16, 2012
Messages
93
Purraise
44
Location
western US
I read several research papers that found a link between fish and hyperthyroidism in cats, but I imagine (or hope) that fish oil as a secondary ingredient is not too big a deal. Unfortunately, there are MANY studies linking canned food to hyperthyroidism, but I suppose that there are always costs and benefits to weigh and wet food is a better option for other reasons. 
 

oneandahalfcats

TCS Member
Top Cat
Joined
Dec 13, 2013
Messages
1,437
Purraise
179
I would be interested in seeing the new research that suggests there is no longer a link between consumption of fish and UTIs in cats. It is my understanding that as fish IS high in magnesium, cats who are prone to bladder infections (UTIs) should not be served fish, in particular tuna and mackerel. I think the white fish might be slightly less of an issue.

The other reason for avoiding fish is that it can trigger allergies in cats as fish contains the protein 'histamine'.

This article at Little Big Cat, makes reference to the link between Fish and UTIs, allergies, hyperthyroidism, and references recent research (Dec 13) that suggests the chemical pollutants in oceans from floating plastics are getting into the fish population : http://www.littlebigcat.com/nutrition/why-fish-is-dangerous-for-cats/
 

oneandahalfcats

TCS Member
Top Cat
Joined
Dec 13, 2013
Messages
1,437
Purraise
179
Thanks for the information vball91 ..

Well, if I have understood things correctly, there seems to be a contradiction between what Dr. Spector is saying based on the study findings that suggest there is no association with ash and magnesium levels and an increased risk for UTIs in cats, and what Cornell is saying. The following passage from the Cornell link touches on how struvite crystals may be less common today due to many commercial diets being much lower in magnesium, suggesting that magnesium is still a concern.

"Struvite stones are becoming less common in cats, as most commercial feline diets are now formulated to reduce the likelihood of struvite formation by limiting the amount of dietary magnesium and by promoting the production of urine that is more acidic. Unfortunately, the percentage of stones composed of calcium oxalate has increased. The role—if any—that diet plays in the formation of calcium oxalate stones is actively being studied".

Here is the link to the Cornell page : http://www.vet.cornell.edu/FHC/health_resources/UrinaryConcerns.cfm (I believe this is the same page that Laurie had posted in the ash-content-and-flutd thread, only the link doesn't work from there, so I went and found the right one).

If commercial diets are containing less magnesium, then it would be sensible that any food served outside of a commercial, diet should also be low in magnesium.

If a cat is consuming a lot of water which works to keep the urethra/bladder flushed, this in itself can help negate issues precipitated by diet. However, if a cat is not drinking a lot of water because they are getting their moisture from wet food, then I would think the contents of that wet food becomes very significant. In this respect I feel that fish still holds too much of a risk. Recently a new member (@AbbyNTim) posted in my thread about Slippery Elm, of her/his experience with Tim who developed crystals after being switched to a wet food diet. The canned diet contained fish and was served almost daily, however, the Ash content was quite low at (1.95%).
 
Last edited:

vball91

TCS Member
Veteran
Joined
Jan 14, 2013
Messages
3,853
Purraise
252
Location
CO, USA
 
"Struvite stones are becoming less common in cats, as most commercial feline diets are now formulated to reduce the likelihood of struvite formation by limiting the amount of dietary magnesium and by promoting the production of urine that is more acidic.
The key in the above statement to me is "and by promoting the production of urine that is more acidic." It's hard to know how much of that is really the factor in controlling struvites. Even though many vets (Dr. Spector and Dr. Pierson included) stress that enough moisture is THE KEY in keeping the system flushed out and healthy, there is no question that some cats have needed methionine (whether in prescription foods or added directly to other foods) to keep urine more acidic and prevent or break up struvites.

I guess the real test would be a study where all other things being equal and only magnesium/ash content was the variable would prove/disprove how important it is, but I haven't found a study specifically on that.

A diet high in magnesium is not good for a number of reasons, so it's a good idea to keep that number low and as noted, there are many good reasons to not feed fish very often. I think this is yet another reason why some of us chose to feed raw/homemade food. It's not just about the quality of the ingredients that go into commercial cat foods. Between the possible toxins and pollutants and BPA scares and carrageenan link to cancer, etc. etc., it's hard to find any foods that you're comfortable feeding. :(
 

oneandahalfcats

TCS Member
Top Cat
Joined
Dec 13, 2013
Messages
1,437
Purraise
179
 
The key in the above statement to me is "and by promoting the production of urine that is more acidic." It's hard to know how much of that is really the factor in controlling struvites. Even though many vets (Dr. Spector and Dr. Pierson included) stress that enough moisture is THE KEY in keeping the system flushed out and healthy, there is no question that some cats have needed methionine (whether in prescription foods or added directly to other foods) to keep urine more acidic and prevent or break up struvites.

I guess the real test would be a study where all other things being equal and only magnesium/ash content was the variable would prove/disprove how important it is, but I haven't found a study specifically on that.

A diet high in magnesium is not good for a number of reasons, so it's a good idea to keep that number low and as noted, there are many good reasons to not feed fish very often. I think this is yet another reason why some of us chose to feed raw/homemade food. It's not just about the quality of the ingredients that go into commercial cat foods. Between the possible toxins and pollutants and BPA scares and carrageenan link to cancer, etc. etc., it's hard to find any foods that you're comfortable feeding. :(
Yup! ... Given that fish is acidifying, it might be considered something worthwhile to feed, but then you have the magnesium content to contend with so its a bit of a catch-22 situation.

Re. the carageenan and cancer, I looked into this recently and found that its not that cut and dried. There are a combination of things that have to happen to cause carcinoma and contamination of food source plays a part. There are two kinds of carageenan - degraded and undegraded. It is the degraded that people and pets have to worry about. Anyway, another topic for another thread.
 
 
Last edited:

abbyntim

TCS Member
Alpha Cat
Joined
Feb 16, 2014
Messages
548
Purraise
47
Location
southern california
I wanted to add a little more information to this thread. It is true that Tim developed struvite crystals in his urine after switching to a wet food diet. He was eating Wellness grain-free every day, rotating among flavors. He consumed fish daily for dinner, either turkey/salmon or chicken/herring. Breakfast was chicken or turkey. We supplemented with a small bit of Tiki Cat plain chicken or chicken/salmon for breakfast (I try to feed a little more in the morning to hold them until one of us gets home from work). As you can see, Tim consumed a fair amount of fish. When we learned Tim had crystals, I was frustrated because a wet food diet was supposed to prevent them. I researched and found catinfo.org, where I learned about the connection between fish and struvite crystals. Our stockpile of canned food was nearly gone and when we re-stocked, we avoided any foods with fish.

About a week later, Tim started vomiting after every meal. It got so bad, we went to the emergency vet one night, where he had blood work and I requested a urine test. This urine test showed no crystals at all (his urine pH was exactly 7.0, a little high). Mind you, Tim had not consumed a bit of fish in about a week. So either the first test was a false positive (possible, given the urine was shipped to a lab; but he'd had urine tests at same vet/lab with no false positives), stopping the fish stopped the crystals, or the second test was a false negative (less likely, done in-house). Fish is out of the picture now. I've not had Tim's urine tested since his emergency vet visit nearly a month ago, but I am closely watching litter box activity and I see no reason to.

Since going to an all-wet diet, Tim appears to get all of his moisture from his food. I add homemade bone broth to his canned food to make sure he is sufficiently hydrated and to help his digestive system. We have two cat fountains, which we purchased in an effort to get Tim to drink more after two serious constipation episodes. When he was consuming almost all dry food, he drank pretty regularly. Now I never see either cat at the fountains, except to check in and make sure they're still running (yes, they get antsy when I shut down a fountain to clean it, even though they seldom or never drink from them).

We are avoiding fish and chicken right now until I feel his digestive system is in better shape, but I may consider fish once in a while or as a minor ingredient in the future. But not daily like before. Not even multiple times a week.
 
Top