Protein Sensitivity

[jem]

I have just purchased a horse with a protein sensitivity. He gets 'protein bumps' when fed too much protein. Luckily he is an easy keeper. He is currently on grass hay only and no grain and is at a healthy weight.

He is not currently 'fit' but we are working him regularly and he will be working a lot as he gets fitter. My question is, should he require more energy and fat as he is worked harder, what should I be looking to add to his diet?

Does anyone have experience with this?

Thanks!

[deltawave]

What IS it, exactly? An allergy? That would be more likely to a specific food product or source of protein (alfalfa, soy, milk protein, etc.) than just "protein" itself. Kind of hard to be allergic to just protein. It would be like an allergy to water, or glucose, or calcium--highly improbable. :)

Although I'm sure if you look around this forum, you will find someone that insists their horse has all of those things. :lol:

[goeslikestink]

What IS it, exactly? An allergy? That would be more likely to a specific food product or source of protein (alfalfa, soy, milk protein, etc.) than just "protein" itself. Kind of hard to be allergic to just protein. It would be like an allergy to water, or glucose, or calcium--highly improbable. :)

Although I'm sure if you look around this forum, you will find someone that insists their horse has all of those things. :lol:

haha i wonder who that could be haha
seriously if an allergy then get it looked t by a vet if you worried as depends waht the allegies
as to how you handle them

for instance theres no such thing as a simple dust allergy - that is lungs can be upper or lower resporority tracks

[jem]

Yes my vet will be out in the next couple of weeks and of course I will be asking him as well.

[pintopiaffe]

I'd check to see if it's reaction to soy and/or alfalfa. They are the two most common protein sources for horses.

Three of the five I've known with soy issues manifested as hives. "Bumps." In summer they would progress to sores and large rubbed areas... often would lose the hair. In winter apparantly they did not itch, but were many small bumps, usually starting chest/neck/back, often showing belly edema.

Removed soy (put them on whole oats and soy free vits/mins) and those three all cleared right up, almost immediately. Two went from absolutely miserable in the summer--"sweet itch", "summer sores" etc., raw, miserable messes, to being 100% fine in the summer with beautiful coats.

Other folks experience different issues with soy, including metabolic. But if I've known no less than five horses--horses I have TOUCHED and GROOMED and WORKED WITH, in my little circle of horses I know on this planet who have a soy allergy, it seems to me it's probably a lot more common than people think. ;)

[Melyni]

I have just purchased a horse with a protein sensitivity. He gets 'protein bumps' when fed too much protein. Luckily he is an easy keeper. He is currently on grass hay only and no grain and is at a healthy weight.

He is not currently 'fit' but we are working him regularly and he will be working a lot as he gets fitter. My question is, should he require more energy and fat as he is worked harder, what should I be looking to add to his diet?

Does anyone have experience with this?

Thanks!

It is most probably a sensitivity to legume protein. Keep him off anything with soy or alfalfa.
Good grass hay, and one good quality vitamin/mineral supplement. Then as you train him and get him fitter, if he loses weight and needs to gain add in something without the soy or alfalfa.

Good Luck
PM me if you need suggestions for Vit/Min supplements.
MW

[sublimequine]

Like the others said, sounds like an alfalfa/legume allergy to me. :)

[jem]

Thanks for your responses. I will post when the vet has had his say as well.

[jem]

Vet has been out and blood tests have been done.

Per the vet:
There were no abnormalities in the testing for the liver or kidneys:
Platelets were slightly low, not a concern
Albumen was slightly low, not a concern
White blood cells were normal - eosinophils were normal
(An increased number of eosinophils in the blood (eosinophilia) usually indicates the response of the body to abnormal cells, parasites, or substances that cause an allergic reaction (allergens).

So looks like we're dealing with a possible allergic reaction to a specific amino acid(s).

I called the previous owner to see what had triggered it. She said it only happened once, and seemed to follow a significant increase in the extruded feed the horse was being fed. After looking at the bag at the feed store, and searching the internet, I could still not come up with an ingredients list. It is a 14% protein feed.

I called the manufacturer and they are going to mail me an ingredients list. Over the phone, she said the main grain ingredients were:
"Barley and/or oats and/or wheat and/or corn. No Alfalfa or Soybean in this one as far as I know.

I will say I don't love to see "and/or" in an ingredients list.

Anyways, it is pretty hard to determine which protein source might be the problem from this. Looks like I might be down to trial and error?

[JB]

Highly unlikely it's an amino acid allergy ;)

However, corn and oats are not uncommon allergens.

[jem]

Highly unlikely it's an amino acid allergy ;)

Why do you say this? Is it extremely rare or what? From the info I gathered on the net, the so-called 'protein bumps' are caused either by the liver not being able to process proteins properly, or by an allergy to a protein. Amino acids are the building blocks of protein, and the general info I'm getting is that it is usually not the protein in it's whole that is the problem, but one or more of the amino acids that make up that particular protein.

If not this then what are the other possibilities?

[Evalee Hunter]

There are 20-some amino acids (AA), which are the building blocks that form protein. (I don'tt remember for sure - 21 or 22.) Pretty much every food has a little protein & thus some AA.

Different animals have different AA requirements. For humans, some AA are "essential amino acids". This means you HAVE to have them in your diet - your body does not manufacture them from other building blocks.

Cows (& other ruminants such as sheep & deer) don't require much in the way of proteins/AA at all. Why? First, you need to understand that the rumen is HUGE - as much as HALF of a cow's weight is the contents of the rumen. The rumen is the "first stomach" & receives everything the cow eats but it also contains millions of protozoa (one celled animals) that help the cow digest its food, and, in particular, the FIBER. As the food progresses through the cow's digestive tract, some of the protozoa get carried along with the food & digested also, and the protozo are just fantastic little protein bits.

I will admit I know less about digestion in horses. What I do know is that practically every food with a significant amount of protein is going to have a variety of AA. It is EXTREMELY hard to control AA intake & keep certain AA to a minimum in the diet.

We see this in humans with a disease called "phylketonuria" (PKU). PKU is an inherited disease where the baby with the disease cannot use one AA, which then builds up & severely damages the individual, causing retardation. The retardation can be prevented by limiting the one AA in the diet - it can be done but it is HARD HARD HARD to do.

Even PKU is NOT an "allergy" to the AA. An allergy involves the immune system mounting an attack on something the immune system does not need to attack - an immune system over-reaction, if you will.

I almost can't imagine how the immune system could over-react to protein in general or to one AA. I can't imagine how life could continue under those circumstances, since protein/AA are so ubiquitous.

Perhaps Deltawave or Ghazzu or RAyers or whoever will come on & correct me ....

[Ghazzu]

Why do you say this? Is it extremely rare or what?

How about impossible?

the general info I'm getting is that it is usually not the protein in it's whole that is the problem, but one or more of the amino acids that make up that particular protein.

Where are you getting this "general info"?

Proteins, yes can be allergens.
Even peptides, which are short chains of amino acids could conceivably elicit a hyperimmune response.

But naturally occurring aa's in feedstuffs, not.

[jem]

Where are you getting this "general info"?

I have been on so many veterinary, and human health sites and have seen it a couple of times. On a quick search, (I'm short on time right now) I couldn't find where in particular. I know you can't believe everything on the internet but I had seen this a couple of times.

So you are saying that proteins, which are made up of aa's, can be allergens, but aa's themselves can not?

Regardless, what should be my next step? Just try him on a particular grain and see what happens I suppose.

[Stacie]

Jem,
Good for you for trying to understand the biochemistry of your poor horse's reaction to his food. The liver can have problems processing types of food without it being a classic immune system controlled allergy. However many, if not most, people call any reaction to a food an allergy and this can be confusing. Not to say that your horse does not have a classic allergy, I'm just pointing out how confusing the word allergy can be.
As far as the amino acid thing. Amino acids are the building blocks of proteins, but it is the shape of the protein, produced by folding the chain of amino acids that actually produces an immune response. The body's immune system responds to shape, like a key in a lock. My husband is horribly, classically, allergic to tomatoes. But if the tomatoes are cooked, like in tomato sauce, the heat changes the shape of the protein (denatures the protein) and he can eat it. On the other hand, a bit of slime on a hamburger where someone has removed a fresh tomato is likely to result in a very green spouse with the potential for vomiting or worse. This also means that the processing of the food can have a great effect. So, for instance, a feed with soy may bother your horse greatly from one feed company and less from another, if soy is the culprit. In addition, vitamins come from somewhere, and the manner in which the vitamins are produced can have a huge impact on animals with food sensitivities. So all vitamins are not equal either. The same for amino acid ingredients. How was the amino acid produced?
Finding a feed type that is fixed formula should be of great benefit. Higher quality feeds are fixed formula and make the food the same way everytime. If your horse can tolerate oats, and you can find an excellent vitamin or ration balancer, those should be sufficient to supply the extra calories and vitamins he needs as long as his hay quality is good.


From:
http://www.elmhurst.edu/~chm/vchembook/565proteins.html

The primary protein structure is defined as the specific sequence of amino acids in the protein.
The secondary protein structure is the specific geometric shape caused by intramolecular and intermolecular hydrogen bonding of amide groups.
The third type of structure found in proteins is called tertiary protein structure. The tertiary structure is the final specific geometric shape that a protein assumes. This final shape is determined by a variety of bonding interactions between the "side chains" on the amino acids. (Folding)

[Ghazzu]

So you are saying that proteins, which are made up of aa's, can be allergens, but aa's themselves can not?


Yes.


Regardless, what should be my next step? Just try him on a particular grain and see what happens I suppose.

I'd try eliminating grain entirely for awhile, then starting back with a single grain, like oats, and slowly adding other ingredients back in to see if there's any reaction.
If he breaks out with a new ingredient, there's your culprit.
It's a bit harder to handle the hay component; even good quality hay has multiple species in it.
But shoot for a grass hay.

I'd agree with a previous post or two that legumes (soy, alfalfa, etc.) are more likely to be the problem than say oats or barley.

You could try either serum or intradermal allergy testing, I suppose.
Trouble with the RAST (blood testing) is that it can turn up a lot of false positives, and the intradermal is a PIA and relatively $$.

[EqTrainer]

Did I read this correctly that the previous owner said it happened ONE time and it was when they fed him *more* of the *same* food?

If I had something like this happen *once*, I would not assume it was the food. It could have been anything. Unless I could reproduce it reliably I would not assume this horse has an allergy to anything, let alone protein. The other thing is that if someone/something is allergic to something in foodstuffs, it's not usually IME dependent on how MUCH of it they get.. but that they get it at all. But that is just my experience with allergic reactions to food. YMMV.

[jem]

Wow a lot of new information here. Very interesting about the shape thing, I had no idea. And EqT, you are right - there is still the possibility that the previous owner had an incorrect diagnosis. She is a fairly knowledgeable and experienced horse person, but still...
I believe I will stay with the grass hay for sure. As far as grains, which are considered 'legumes'?

As he is worked a little harder I will likely add a grain, haven't decided which is first. But will take Ghazzu's advice to add one thing at a time. I have had the same advice on other forums and it only makes sense to me. I think if I find a grain that helps to keep him at a good weight and energy level, I will just stick with that.

I don't think I will do any further testing as it is expensive and sounds like it may not tell me much in the end?

Thank you all for your posts, I have learned a lot!

[JB]

Legumes would be peas or soybeans, but not oats/barley/corn. Alfalfa and clover are also legumes.

As for working harder and adding grain - you don't need to add *grains* to add beneficial calories. You can use alfalfa pellets or beet pulp as the base, and can use rice bran and black oil sunflower seeds, if necessary, for some additional concentrated calories. But don't forget the nutrition - just as important as more calories, and the right nutrition can reduce or even eliminate the need for MORE additional calories :)

[Evalee Hunter]

. . . . Alfalfa and clover are also legumes. . . . you don't need to add *grains* to add beneficial calories. You can use alfalfa pellets . . . .

Since there is a suspicion the horse could be sensitive to legumes & alfalfa is a legume, adding alfalfa for calories doesn't seem to make muich sense.

[JB]

Since there is a suspicion the horse could be sensitive to legumes & alfalfa is a legume, adding alfalfa for calories doesn't seem to make muich sense.

Given that "\it only happened once, and seemed to follow a significant increase in the extruded feed the horse was being fed. it's probably not very likely at all that alfalfa, or any specific legume, was involved.

However, I suppose it IS possible that a horse can tolerate a lower level of X but not a higher level. I'd think that would be quite rare though?

However, you're right, in that alfalfa is probably not the first thing I'd add back for more calories.

[jem]

Where are you getting this "general info"?

Proteins, yes can be allergens.
Even peptides, which are short chains of amino acids could conceivably elicit a hyperimmune response.

But naturally occurring aa's in feedstuffs, not.


Ghazzu: Here is one of the links I was looking at regarding the allergy to amino acids: see the first question and 'Long Answer':
http://www.allaroundperformancehorse.tv/DrAnderson_past.html

[Ghazzu]

Sounds, at best, overly simplified.

Do you happen to know just what Dr. Anderson has a doctorate in?

Edited to add--he's apparently a PhD in nutrition.
I'm surprised he'd make a statement that sloppy.

[jem]

Well thank you for your reply. That's just it, we try to make sense the best we can of the info we get and from what sources.

We are ramping up said horse's work load a little and he is slowly losing weight on all the grass hay he can eat. He had some reserves so looks pretty good. I have him on a bit of barley to get him onto it and will increase it as needed. He has a free choice mineral block and salt of course. If the barley agrees with him I will just stick with that.

I'll post again if I have any new info or occurences.

Meantime thank you for your input all!

Elaine.