The new horse I got 
  in January has been doing really well, but not putting on weight like I 
  thought he should. I have wormed him 3 times with Zimectrin. Which I have used 
  for many years with great results.  Well , he whacked his knee on the 
  fence, and so I decided to take him in for Xrays.  ( which is all fine) 
  Since I really like this horse, and plan to keep him, I thought it was a good 
  time to get him a really good going over. A fecal revealed ALLOT of worms, and 
  a blood test revealed that he is very anemic. I was surprised at all of this. 
  He has done extremely well on his first 4 rides, with actually awesome 
  recoveries, and a real going down the trail attitude, full of spunk and 
  energy.  He has received allot of great compliments on what a great 
  looking /moving /going horse he is .  The ONLY thing that was 
  not quite rite is that he remained kind of thin, and I just put that down to 
  his 1/2 Saddlebred  long tall hard keeper profile.  He is now into a 
  good purging program, and I expect he will pick up considerably.  I 
  appreciate all the talk on RC lately about this subject, it kind of wakes us 
  up. I think fecal testing is something we should all take allot more 
  seriously. With all these great do it yourself wormers, that claim to get them 
  all and with rotation, it is a great thing. Certainly economical.  But I 
  think we have all gotten a bit complacent about getting those fecals 
  done.  Way back when.... all our worming were done by the vet, the tube 
  worming, and the vets would usually do the fecals as a matter of course. Gads 
  I can't remember the last time I had a fecal done on one of my horses. How 
  about you???  I know it will once again become a more regular part of my 
  horsekeeping  plans.  And also just because they are fat and look 
  like they feel good does not mean they don't have hidden problems.  I 
  still can't believe how really bad off this horse is.I thought he was in great 
  shape. And if he hadn't whacked his knee, which is what got us to the vet, who 
  knows the outcome! I would of just kept on feeding all those worms that 
  great feed Susan is always telling us about. I am amazed that he has done so 
  well in that shape. A testimony to the heart of these great animals.  Now 
  I am wondering if I can actually ride him when he gets past all of this, and 
  gets in really good shape.  Get those fecals done!! Annie G.