Studies have been done to determine which types of mattresses are the best for the cows, and many people have found that sand works just as well as other bedding for the comfort of cows.

• 更有人针对哪种床垫最适合牛只进行数项研究，而许多人发现，沙床和其他衬垫一样能提供牛只舒适的环境。