The normal packed cell volume of a snake ranges between 20% and 30%. The blood volume (based on the black ratsnake, ''Elaphe'' sp.) is equivalent to approximately 6% of the animal's body weight. | The normal packed cell volume of a snake ranges between 20% and 30%. The blood volume (based on the black ratsnake, ''Elaphe'' sp.) is equivalent to approximately 6% of the animal's body weight. |