Cow hooves contain a material known as keratin, which has many industrial and household uses. It is an important ingredient in a foam used to extinguish fires at airports caused by aviation fuel. Keratin is also used in many hair care products, such as shampoos and gels. Fat from the hooves might be rendered for use in pet food as well as a myriad of other products, while the bone is ground into bonemeal.
The oldest use for cow hooves is probably boiling them to make glue. This has been done for thousands of years in order to create both an adhesive and a kind of lacquer. It is still used for traditional craft-work today.
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