The washerman did so after sunset, and the donkey returned unharmed after he had eaten to his heart's content. 
 
From then onwards, the washerman would cover his donkey with the tiger's skin every night and lead him to the fields. The farmers did spot him, but mistook it for a tiger. They did not even venture out of their homes in fear. All the time, the donkey ate as much as he liked and returned home. In the morning, he would stand in the washerman's stall without anybody suspecting anything. 
 
As time passed, the donkey regained his health, and the washerman did not have to worry about his food. 
 
One night, as he was feeding on the fresh barley crops in the fields, he heard a sound. It was a female donkey braying from a distance. He was attracted and brayed in return. 
 
The farmers, who were watching him from inside for fear of the tiger, heard this and realized that it was a donkey and not a tiger. They came out to observe, it was indeed a donkey dressed in tiger's skin. They chased the donkey with sticks, and killed him. 
 
The wise indeed say:
Do not pretend to be what you are not.