Question about fish in cat food

Common wisdom among people who know something about feline nutrition
is that cats should't be fed fish too often. But a question about it
from a friend made me realize that I'm not sure why. Is it because of
the presence of mercury in (wild) fish? Is that also the reason why
one shouldn't feed a cat too much tuna, or is that a separate issue?

Also, does anyone know whether farmed fish has a lower mercury content?
I would expect it to since they have more control over the water.

Thanks.

--
Joyce

Cats' hearing apparatus is built to allow the human voice to easily
go in one ear and out the other. -- Stephen Baker

On Friday, December 16, 2011 1:54:40 PM UTC-7, (unknown) wrote:
Common wisdom among people who know something about feline nutrition
is that cats should't be fed fish too often. But a question about it
from a friend made me realize that I'm not sure why. Is it because of
the presence of mercury in (wild) fish? Is that also the reason why
one shouldn't feed a cat too much tuna, or is that a separate issue?

Also, does anyone know whether farmed fish has a lower mercury content?
I would expect it to since they have more control over the water.

Thanks.

Well... finally found somethng that appears a bit reputable:

http://pets.webmd.com/cats/10-mistak...e-feeding-cats

Says raw fish is out, and a total fish diet is not good as it can cause some serious vitamin deficiencies.


--
Joyce

Cats' hearing apparatus is built to allow the human voice to easily
go in one ear and out the other. -- Stephen Baker

In ,
shouted to everyone in earshot,
Also, does anyone know whether farmed fish has a lower mercury content?
I would expect it to since they have more control over the water.

My understanding is that mercury comes from what fish eat, not
directly from the water into the fish. plants absorb it from the
water and/or soil, fish eat plants, other fish eat those fish, etc.
the lowest-mercury fish are those that are small, herbivorous, and
short-lived like tilapia, and larger fish, carnivorous fish, and
longer-lived fish, like salmon and orange roughy, will have more
mercury.

farming, I believe, is a mostly matter of providing feed to fish that
are already in a particular area rather than keeping them in a
controlled environment, at least in the case of ocean fish. the
provided feed might reduce the amount of ocean life that the fish eat,
but I wouldn't expect it to entirely replace their natural diet.
also, some farming operations use corn in the feed, so there could be
abnormal levels of fat in the fish, and the extra fat would be omega-6
rather than the omega-3 you'd expect from fish, for whatever that's
worth.

On 16 Dec 2011 20:54:40 GMT, wrote:

Common wisdom among people who know something about feline nutrition
is that cats should't be fed fish too often. But a question about it
from a friend made me realize that I'm not sure why.

Years ago I did foster care for a cat rescue group and routinely used
canned mackeral when socializing fearful or feral cats. I was told
that a regular diet of fish was bad because it leached calcium from
the bones and could soften them.

FWIW.

Years ago I did foster care for a cat rescue group and routinely used
canned mackeral when socializing fearful or feral cats. I was told that
a regular diet of fish was bad because it leached calcium from the bones
and could soften them.

FWIW.

I wonder if fish contains appropriate levels of taurine? If not, that
would certainly be a good reason to not feed too much of it.

"Smokie Darling (Annie)" wrote:

On Friday, December 16, 2011 1:54:40 PM UTC-7, (unknown) wrote:
Common wisdom among people who know something about feline nutrition
is that cats should't be fed fish too often. But a question about it
from a friend made me realize that I'm not sure why. Is it because of
the presence of mercury in (wild) fish? Is that also the reason why
one shouldn't feed a cat too much tuna, or is that a separate issue?

Also, does anyone know whether farmed fish has a lower mercury content?
I would expect it to since they have more control over the water.

Thanks.

Well... finally found somethng that appears a bit reputable:

http://pets.webmd.com/cats/10-mistak...e-feeding-cats

Says raw fish is out, and a total fish diet is not good as it can cause some serious vitamin deficiencies.

Thanks! That was helpful.

--
Joyce

Cats' hearing apparatus is built to allow the human voice to easily
go in one ear and out the other. -- Stephen Baker

"Dan M" wrote in message
...
Years ago I did foster care for a cat rescue group and routinely used
canned mackeral when socializing fearful or feral cats. I was told that
a regular diet of fish was bad because it leached calcium from the bones
and could soften them.

FWIW.

I wonder if fish contains appropriate levels of taurine? If not, that
would certainly be a good reason to not feed too much of it.

We are very lucky nowadays that cat foods are available in many forms,
kitten foods, senior foods etc Makes you wonder how they ever survived on
the scraps they had many moons ago. Obviously they did or we wouldn't have
their descendants.
Tweed

JB wrote:

In ,
shouted to everyone in earshot,
Also, does anyone know whether farmed fish has a lower mercury content?
I would expect it to since they have more control over the water.

My understanding is that mercury comes from what fish eat, not
directly from the water into the fish. plants absorb it from the
water and/or soil, fish eat plants, other fish eat those fish, etc.
the lowest-mercury fish are those that are small, herbivorous, and
short-lived like tilapia, and larger fish, carnivorous fish, and
longer-lived fish, like salmon and orange roughy, will have more
mercury.

farming, I believe, is a mostly matter of providing feed to fish that
are already in a particular area rather than keeping them in a
controlled environment, at least in the case of ocean fish. the
provided feed might reduce the amount of ocean life that the fish eat,
but I wouldn't expect it to entirely replace their natural diet.

But (I would assume) they would be feeding them food that doesn't have
mercury in it. Maybe I shouldn't assume that...

also, some farming operations use corn in the feed, so there could be
abnormal levels of fat in the fish, and the extra fat would be omega-6
rather than the omega-3 you'd expect from fish, for whatever that's
worth.

That's disgusting. The food industry puts corn (in one form or another)
in *everything*. Not healthy for cats or humans.

--
Joyce

Cats' hearing apparatus is built to allow the human voice to easily
go in one ear and out the other. -- Stephen Baker

On Fri, 16 Dec 2011 22:26:11 +0000, Christina Websell wrote:

We are very lucky nowadays that cat foods are available in many forms,
kitten foods, senior foods etc Makes you wonder how they ever survived
on the scraps they had many moons ago. Obviously they did or we
wouldn't have their descendants.
Tweed

Indeed. I'm guessing that the occasional bird or vole must have helped
make up for any deficiencies they might have had.

wrote:

On 16 Dec 2011 20:54:40 GMT, wrote:

Common wisdom among people who know something about feline nutrition
is that cats should't be fed fish too often. But a question about it
from a friend made me realize that I'm not sure why.

Years ago I did foster care for a cat rescue group and routinely used
canned mackeral when socializing fearful or feral cats. I was told
that a regular diet of fish was bad because it leached calcium from
the bones and could soften them.

Do you think this could be true for dogs, too? I know that cats and dogs
have some different nutritional requirements, but something like calcium
being leached from bones seems like it would apply to dogs and cats, and
humans, for that matter. (But that's just a theory, I don't actually know.)

--
Joyce

Cats' hearing apparatus is built to allow the human voice to easily
go in one ear and out the other. -- Stephen Baker