I first heard this one from Dr. S. Elrod, all too many years ago.
An ambitious, but ignorant entrepreneur, decided he would increase his considerable fortune by getting into the thoroughbred racing business. He bought a ranch in Kentucky, stocked it with good horses, and hired some folks to go about amassing his big bucks while he followed other pursuits.
He quickly found, however, that the money flow was only in one direction — out of his pocket. He decided to make a surprise visit to his ranch, and found to his horror, that unbeknownst to himself, he had been financing a gentle retirement home for lazy race horses. His livestock was there, all right, but each horse gave clear evidence of living a wholly sedentary life. The horses were grossly overweight and fat, in fact. Moreover, they were so unused to moving that many small birds had built nests in their hair, and these birds were busy raising their young.
The erstwhile horseman was incensed. He summarily fired all his ranch hands. Next, he grabbed a ladder and garden rake, and he started cleaning up his horses, ripping the bird nests from off their backs. In his angst, he gave these now immortal instructions to his new helpers. “Beast is Beast, and Nest is Nest, and Never the Mane Shall Tweet!”