Re: heat fatigue and dark urine

[Tivers <Tivers@aol.com>]

In a message dated 98-05-04 16:19:22 EDT, step@fsr.com writes:

<< 
 p.s. 
 
 Any of the vets or experts out there want to comment on what effect over-
heating
 has on the horse's metabolism? We pulled our older Orlov (my husband was
riding
 him) at 40 miles. He pulsed down ok at the last check, but was very sluggish
 at the trot out and just looked plain tired. Didn't seem worth it to subject
him to
 another 10 miles in the heat, but more important in our decision to pull him
was
 that he peed a small amount of very dark urine. The reduced volume and the
 dark color looked like trouble.
 
 I later talked to several others who saw the same thing in their horses - no
obvious
 muscle problems, just fatigue and dark urine... so what's going on to cause
 the dark urine? Must be some muscle tissue breakdown somewhere...
 
 comments??
 
 Steph
  >>

That's myoglobin from muscle cells. The small amount of urine may indicate
dehydration as being the main problem here. 

ti