Comment by MaDeuce
And contact lenses too. A HBS case study I remember from grad school:
"Optical Distortion, Inc" A new product, contact lenses for chickens, is to be introduced by a small firm formed to market the product. An entry strategy must be planned including price, sales force, size, and location. Allows data for computation of economic benefit to farmers. Includes state-by-state chicken population data for planning a rollout sales program.
Looks like he actually tried it:
https://www.vice.com/en/article/chickens-wore-sunglasses-ind...