Iron revisited

 Interesting article Ron; thanks for posting it. Which EVO product are you referring to; of their dry foods, the lowest amount of iron is 236 mg/kg, and the Red Meat is 378 mg/kg. Their wet foods list less iron in the nutritional analysis, but on a dry matter basis the beef, for example, is 293 mg/kg.

    According to the NRC requirements for adult maintenance, Shadow needs about 12.7mg of iron daily.

ottoluv

It's important to keep in mind that these levels they list are ranges because every dog will absorb a different amount. You can calculate out the wazoo, but the only way to know how much they are actually absorbing and if it's too much is by checking iron studies. Also, I'm not sure in dogs, but in people, it's near impossible to make someone become iron toxic for this reason. The body is quite good at not absorbing things from the GI tract it doesn't need.

 Couldn't have said it better myself!
 

ottoluv

Also, I'm not sure in dogs, but in people, it's near impossible to make someone become iron toxic for this reason. The body is quite good at not absorbing things from the GI tract it doesn't need.

  I'm surprised to learn that since you often hear warnings on the news about over doing supplements.  This is what the NRC has to say about iron;

Free Fe [Iron] in the body is extremely reactive, catalyzing oxidative reactions that can lead to tissue damage. When only a small amount of Fe is ingested, it is firmly bound to proteocytes such as apoferritin, transferrin, and hemosiderin in enterocytes, plasma, and storage sites such as macrophages. Iron resulting from hemoglobin degradation is efficiently reutilized but is virtually always present in protein-bound form. However, the total binding capacity of all such proteins is small and can be overwhelmed by intake of larger amounts of Fe, resulting in the presence of toxic amounts of free Fe in the system
 

think of it this way, too much potassium in the blood will kill you via cardiac arrythmias. We routinely eat way more potassium then we need, but you don't absorb it. Which is why I can eat four avocados and not die. If you put the equivalent amount of potassium from those four avocados in my blood, you would kill me. In one slice of avocado you have 25% of your daily allowance of potassium. If you ate two avocados you would have about 300% of your daily value but it doesn't mean you absorb it all. Physiology is much to complex to try to explain via multiplication and division ;)

All right, so either our dog's nutrition is a fragile balance that requires veterinarians, ANs, and PhDs, to formulate commercial dog food products for us, because we are too stupid to manage to feed a sensible diet to our pets, ourselves.  Or else dogs really do have a wide range of nutritional needs reflective of a scavenger, and home based feeding isn't the idea of Beelzebub, preparatory to killing our dogs, that vets and dog food companies tell us it is.

I'm sorry but the dog food companies can't have it both ways.

 

Iron is something I've had tons of discussions about with my regular vet, holistic vet and the vets up at the University of FL who treated Billy for the IMHA.

I don't know the poor dead horse, but the only thing I'd throw out (that's not mentioned above other than the mention that all are 'different';) is in MY experience iron became a big deal during the IMHA treatment because Billy was tranfused six times in one month and the body had a long hard haul to manufacture blood FAST ENOUGH because of the continued blood/anemia problems inherent in the IMHA until we truly got the disease under control.

For a **brief** time they had me give him oral supplementation (in addition to all the beef heart, beets, figs, dates, leafy greens and such that I could shove in his mouth) but we TESTED MONTHLY.  And "iron" isn't something included in even Antech's "Super Chem" panel (the big huge complete panel) but you specifically have to ask for iron to be tested in addition.

His was a completely unique situation -- I'm not trying to generalize, but it's what caused me to have to be concerned about iron and it's positives and negatives. 

However, in passing conversation one day, my holistic vet made the comment to me that each being has unique needs.  Generally you don't find men often with low iron but you DO find women low iron.  BUT **specifically** you find pre-menopausal women who are low iron because they lose blood every month, but often you don't find para and post-menopausal women prone to low iron for the same reason.

However, it's not all that uncommon to find men with overly *high* iron (and in toxic amounts) -- I had a boss once who was diabetic, but because of the diet he chose to consume and his lifestyle combined with his diabetes, he also had iron toxicity (and used to go and have blood taken at the blood bank monthly -- just to reduce the amount of iron in his body and it could *not* be donated because of the iron toxicity). 

Dogs typically aren't low iron if they are healthy.  But I can see with the high protein foods being fed where it might be a concern. 

Periodically, even now, when we have Billy's quarterly blood draws I ask them to include the iron level just to keep an eye on it *only* because it was a concern in the past. 

But with the foods that are high in iron (meat specifically) there can be other things in the blood and urine that may be problems. 

I'm still going to say -- I think doing a blood panel on a dog if an iffy situation arises -- even just to establish a baseline if it doesn't show anything significatn --- is not a bad idea.  We're currently trying to find out why Luna tends to be so much on the thin side and we did a Super Chem on her last week that turned out perfect.  I don't think we wasted a dime -- because now we have a 'baseline' of how her blood was now if we ever need it. 

Not trying to conclude anything here -- but one of the things I'd be concerned about if you were feeding high iron would be what the hematacrit was at and how close that is to breed norm.  Just a thot.

http://www.irontoxicity.com/index.jsp

Even my example of what amount Shadow eats, he's only mathematically exposed to 22 mg of iron, quite a bit less of the 40 mg the other math was suggesting.

And I don't think all dogs will suffer GI upset from iron exposure. And I think it depends on how the iron is chelated but those are just my musings.

But I will be hornswaggled. It's got me looking at formulas to make sure that the iron is a sulfate rather than a proteinate. Even then, one might run the risk of anemia but it can be countered by feeding meat, to some degree.

As for blood tests, it only tells what the picture is for that hour of life. But it can still be a handy tool.

calliecritturs

His was a completely unique situation -- I'm not trying to generalize, but it's what caused me to have to be concerned about iron and it's positives and negatives. 

calliecritturs

not all that uncommon to find men with overly *high* iron (and in toxic amounts) -- I had a boss once who was diabetic, but because of the diet he chose to consume and his lifestyle combined with his diabetes, he also had iron toxicity

and yep **THAT** is what I said (1 in 500 isnt' common nor is it 'rare';) and I think I made the point that he was unusual (had you ever worked for him you would have known HOW unusual *sigh*)!

calliecritturs

but one of the things I'd be concerned about if you were feeding high iron would be what the hematacrit was at and how close that is to breed norm

A hematacrit is NOT a measure of iron and I didn't say it was.  (in fact I made a point above that it's not even *included* in the extensive dog blood profile - you have to ask for it special to have it tested) -- only that if you were feeding a high iron food *I* would keep an eye on the hematacrit (shoot, I have blood drawn on my senior dogs along with a urinalysis just so the vet CAN keep an eye on it - a full senior profile).

Wasn't saying I would be terrified -- only that it would merit watching ... like anything else.

As for blood tests, it only tells what the picture is for that hour of life. But it can still be a handy tool.

ottoluv

That's not true at all, it can tell you your body's iron stores as well.

My bad. I am reminded of a young guy I worked with who was hypoglycemic. He could tell when his sugar was dropping before needing to check it and eat something. Therefore, the idea that one's blood analysis can change from hour to hour.

And your right, the body could already have a store of iron. Hence the statement in the article that one dog might become susceptible to iron toxicosis while another dog of maybe the same size fed the same dose has no problems. I also think of working dogs, who sometimes have a higher need for iron supplement.

Women, of course, during childbearing years especially, sometimes need iron supplement if they get anemic when their aunt visits. That might only change from day to day.

This thread makes a little more sense ...

but it does seem like we would be better served as dog owners if a company would come up with hair analysis for our pets to see if they getting too much of something and not enough of another.. perhaps a test exists but isn't available to the mass market. ?

I did learn some more information which I got from a vet with a specialty in small animal nutrition and a further specialty in the nutritional needs of ailing animals. IOW, she's been doing this for a few decades and is qualified as opposed to us armchair nutritionists who read a few pages here and there.

Though the AAFCO updates every year, the NRC specs are based on animal tissue needs, not recommendations of dry ingredients. The AAFCO makes recommendations on ingredients. Hence, the actual range of 80 to 3,000 mg of Fe per Kg of dry matter of dog food, if the food is providing about 350 kcal. The AAFCO guidelines are, indeed, based on NRC figures from 1985, not 1982 or 1981. And they are only recommendations and the AAFCO does not carry the weight of law. A food company does not have to put in, say, 150 mg per kg of food. They might only put in a trace amount if there is plenty of iron in other ingredients, which is actually the case in a lot as the idea is to present a balanced profile. The NRC did, as we know, make some changes in 2006. And the AAFCO and NRC are actually working on a closer liaison which result in better, faster communication.

And how much of an ingredient prior to processing is present is not a direct link to how much the dog is absorbing on an as-fed basis, which has been my point all along. The amount of nutition absorbed by the dog can only be determined on an as-fed basis, hence the need for feeding trials. And true, one or two dogs might fall out of a particular feeding trial but that is more likely due to personal metabolisms of the dogs than a particular failing of a food though, granted, dogs can withstand malnutrition for a long time but, in the case of something like iron toxicosis, that would show up pretty quickly.

And even my math is based on some general figures. As you pointed out, maybe a hair analysis of the dog might be a better picture. And have some dogs possibly suffered ill effects from long term iron oversupplementation? That's always a possibility. Each dog is different. One dose might by fine for 80 dogs and the next two might suffer ill effects because of individual metabolism or other food items consumed that are not balanced with the ingredients of the diet. That's why most commercial dog foods and a number of vets recommend that you don't feed your dog a lot of table scraps, etc., if you are feeding them a prepared dog food.

But, even at 80 mg per kg of food, the likelihood of iron overdose is minimal, depending on how the iron is chelated. Most salts are water soluble, therefore easily passed and the excess can be excreted. A sled dog in the Yukon Quest will have a higher iron requirement than a 12 lb couch potato. So, we should certainly be careful and keep our eyes open. Generally, if your dog is doing well, then they are. But it can't hurt to get tests for this, that, and the other thing. And I like the idea of the hair test. It's the least invasive and if, like humans, it can show a snapshot of blood chemistry or tissue chemistry, it could be another great tool.