Re: Probiotics and body temperature

[Susan Evans Garlinghouse <suendavid@worldnet.att.net>]

The horse I ride is one of the
> these three, and I noticed that he has a chronically depressed body
> temperature (don't know about the other two).

> This got me wondering if horses with normally high or low body temperatures
> are not able to maintain a good level of gut flora, knowing that bacteria can
> be very sensitive to temperatures.

Off the top of my head, there probably isn't alot of relationship
between the two, as core temperatures (as would be present in the cecum
and colon, where the gut flora are) is going to have to be within pretty
close temperature ranges---if they were'nt, there would be far greater
effects on other components of metabolism, like enzymes.  But, it's an
interesting thought.

There are other things that can possibly explain differences in body
temp, like the amount of forage the horse is eating, type of grain,
etc.  Fiber is less digestible and creates more waste heat (which then
must be thrown off by the body) than more digestible feeds like grain,
fats or soluble fibers like beet pulp.

> 
> Then I opened the latest KV Vet Supply catalog to order a new supply of
> Fastrack, and find it now listed under Livestock, rather than Equine supplies,
> and the description says it improves the appetite of cats and dogs as well as
> horses!
> 
> I thought gut flora were pretty much species-specific.  Is it possible that
> the same flora benefit humans (Fastrack contains Lactobacillus acidophilis),
> cats, dogs, and horses?

Some species of bugs are species specific, some are not.  Lactobacillus
acidophilus, for example, happily establishes in almost any species that
eats soluble carbohydrates, which is why live-culture yogurt is good
stuff for almost anyone.



> I would be interested in (1) any comments on why horses might need probiotic
> supplementation (why they would be deficient in the first place),

As you mentioned above, gut flora are sensitive to temperature; and also
very sensitive to pH.  When a horse is stressed, one or both may change,
and some of the gut flora population will die off.  Antibiotics, worming
medicines and other drugs can also affect the bugs, or changes in the
ration.  For example, some species thrive on the soluble carbohydrates
in grain---if a horse gets an unexpected large meal of grain, the
carbo-loving species multiply very rapidly.  Alot of those same species
secrete lactic acid, so the pH of the cecum becomes more acidic.  If it
becomes too acidic for some pH-sensitive species to tolerate, they die. 
That will do possibly two things; 1) the gut flora population becomes
unbalanced as the lactic-acid-producing species crowds out other
species, and 2) some of the now-dying-off species secrete a second
substance called endotoxins as they die.  Theses are absorbed through
the intestine, damage the mucosal lining of the gut and can cause
laminitis.

So the whole idea of probiotics is to continually re-seed the gut with
fresh supplies of microbial species to keep the population flourishing
and somewhat balanced, or at least not consisting exclusively of just a
few species.  That's also why I personally prefer probiotics that
provide more than just the Lactobacillus species.  

> 
> BTW, the three horses on Fastrack DID hold their weight better this fall as
> the pasture grass depleted.

Good. Glad to hear it.


Susan G