This is the bass line played throughout the song, and it's correct but you have to listen carfully for it.
[ Tab from: https://www.guitartabs.cc/tabs/e/elvis_presley/hound_dog_tab_ver_2.html ]
E|-------------------------------------------------|
B|-------------------------------------------------|
G|---------------------------------------5-------5-|
D|--------5-------5-------5------5-3-5s7---3-5s7---|
A|--3-5s7---3-5s7---3-5s7---3-5s7------------------|
E|-------------------------------------------------|
E|-------------------------------------------------|
B|-------------------------------------------------|
G|------------------------7-------5----------------|
D|--------5-------5-5-7s9---3-5s7---------5-5555555|
A|--3-5s7---3-5s7-------------------3-5s7----------|
E|-------------------------------------------------|
Repeat throughout the song!!!!!