Last year Illinois and Texas lawmakers passed legislation that closed the remaining horse slaughter facilities in the U.S. But this may just be the tip of the iceberg.

Sharon Marohl is president of the Missouri Equine Council and says the number of unwanted horses is growing nationwide.

"It's just that there's too many horses and too few owners," said Marohl. "The latest estimates by the American Horse Council were that the average horse owner is only a horse owner for 4.5 years."

Marohl says there are a number of factors contributing to the problem.

"Feed costs have gone up tremendously because the price of hay has gone up with the increase in fuel," said Marohl. "As far as the horse slaughter issue goes, 90,000 horses is the estimated average that went to horse slaughter. Now where are those horses going to go? At best, estimates what I have seen, is large animal rescues can house 6,000 horses. That's United States wide."

One veterinarian says the long term effects of banning horse slaughter in the U.S. is only going to increase the number of unwanted horses.

"What probably started off as a good idea in that trying to be humane and trying to avoid unwanted pain or suffering has inadvertently turned into causing even more pain and suffering potentially because of there being so many unwanted animals now," said Cliff Miller of Green Hills Vet Clinic.

Marohl says all of this is causing the price of horses to go down. Now, it's not unusual for people to give horses away for free.

The president of the Missouri Equine Council says one resolution to the problem is responsible horse breeding. And she said, for the most part, this means stop breeding unless the animals are of exceptional quality.