Why did they horses to slaughter houses?

It's important to clarify that the phrase "they" is a bit vague in this context. Are you asking:

* Why are horses sent to slaughterhouses? This would focus on the reasons horses are considered unsuitable for other purposes and end up being sent to slaughter.

* Who sends horses to slaughterhouses? This would focus on the individuals or organizations involved in the process of transporting horses to slaughter.

Here's a breakdown of potential reasons why horses might be sent to slaughterhouses:

* Age and health: Horses that are old, injured, or have health issues that prevent them from working or competing may be considered unsuitable for other uses.

* Economic factors: Owners may choose to send horses to slaughter if they are no longer economically viable to keep due to costs of feed, veterinary care, and housing.

* Lack of suitable homes: Horses that are abandoned, neglected, or unwanted may end up in slaughterhouses if they cannot be placed in suitable homes.

* Overpopulation: In some cases, there may be more horses than available homes, leading to some horses being sent to slaughter.

Who sends horses to slaughterhouses?

* Individual owners: Owners may decide to send their horses to slaughter for a variety of reasons.

* Horse auctions: Some auctions specialize in selling horses for slaughter.

* Horse dealers: Some dealers buy and sell horses, and may ultimately send some to slaughter.

It's important to note that:

* Horse slaughter is a complex and controversial issue. There are strong arguments for and against it.

* There are alternatives to slaughter. Many organizations work to rescue, rehabilitate, and find homes for horses.

* Consumers have a role to play. By being aware of the issue and making informed choices, consumers can support ethical treatment of horses.

If you have any specific concerns about horses being sent to slaughter, it's best to research the issue further and learn about the organizations working to protect horses.