Is Hound Dog by Big Mama Thornton the first Rock and Roll song?

There's still an ongoing debate about who should be credited with the first Rock & Roll song. Some say it's Bill Haley's "Rock Around The Clock", while others say it's Elvis Presley's "That All Right Mama". Haley had an even earlier song called "Crazy Man, Crazy" that was the first Rock & Roll record to officially hit the Billboard chart.

Regarding Big Mama Thronton, the term Rock & Roll had not been coined yet in the 1940's, and many people do not believe that pre-1950 music should qualify.

Hound Dog is really more of a blues song, Rocket 88 is largely considered to have been the first rock song. It was written and recorded by Ike Turner in 1951 although it was credited to a non -existent band, Jackie Brenston and his Delta Cats...

I think officially it is Bill Hailey and the comets.