Simplify the following text for a Grade 7 native English-speaking person.
Original: Della P was bred in Louisiana , a leader in breeding short distance racehorses between 1900 and 1940 , and was taken to Arizona by Parker .
Simplified: Della P was bred in Louisiana , which was a leading state breeding short distance racehorses during the years 1900 â `` 1940 . Della P was brought to Arizona by Parker .