Nasatya - Dasra

Nasatya - Dasra Surya found out that Samjna was in Uttara Kuru in the form of a mare. He joined her there in the form of a horse. As horse, they had two sons named Nasatya and Dasra. Since ashva means horse, the sons were also known as the two Ashvinish and became the physicians of the gods. http://www.gita-society.com/section3/HinduPuranas16.htm