Do they use horse hooves in glue?

No, horse hooves are not used in modern glue.

Historically, animal parts like hooves, bones, and hides were used in some types of glue. However, modern glues are primarily made from synthetic materials, like:

* Polyvinyl acetate (PVA): The most common type of glue found in households.

* Polyurethane: A strong and durable glue often used for woodworking.

* Epoxy resin: A two-part glue that creates a very strong bond.

While some traditional glue makers may still use animal-based products, these are less common today.