Re: Shampoo and pH for Horses & Cattle

Cody:

     Good question, sorry about the delays.  I am not certain I have the 
exact answer to your question, but on first principals I would suggest the 
following;

The natural pH of skin and hair in humans is about 5.5-6.  This means that 
relatively speaking, water alone is more basic than hair.  Apart from 
flame, the only thing to which hair is chemically sensitive is highly 
basic conditions.  It is essentially resistant to acids and weak bases 
have the effect of swelling the hair, denaturing some of the proteins 
within the keratin and allowing some of the detergents and moisturizers to 
penetrate deeper into the cuticle or the inside of the hair.  The use of 
acid balanced (pH balanced shampoo) on your livestock is probably much 
more concerned with not drying the skin and creating a skin problem than 
the specific effect on the hair itself.  Livestock hair, and horse hair in 
paritcular has an extremely thick shaft, with a lot more keratin coating 
than human hair.  It is likely more resistant to the effects of high pH 
shampoo's and can tolerate a higher pH with the observation of more 
softening from the basic shampoo you are using.

     Another possibility is that there is a difference between the pH of 
something and the buffering capacity.  Something could be a high pH but be 
very sensitive to even a small amount of acid.  A very dilute solution of 
Sodium hydroxide (NaOH) would have a pH of 12-14, but even a small 
addition of vinegar (3% acetic acid) would drop the pH very quickly.  
Likewise, the high pH shampoo may be weakly buffered, which shortly after 
being applied to the horses neutralizes quickly to pH7.0.  This is 
something you could check.  The pH of the shampoo vs.  the 
shampoo/lather/water after being applied.  The control for this experiment 
is the washings from your horse with NO shampoo, not just the pH of the 
shampoo itself.

     My feelings on husbandry are that if you have been using it without 
ill-effect for years, it is probably worse to change in mid-stream, pardon 
the pun.  You could always check with your large animal vet if you have 
other concerns.