Why is a hotdog named after a heated canine?

The answer is explained here:

http://en.wikipedia.org/wiki/Hot_dog#Etymology

The name "hot dog" was actually contrived in the 1940's following the publication of a newspaper article in the New York Times that depicted the popular meat producer, Oscar Mayer, as a canine molester.

Oscar Mayer was caught with a dog, a jar of peanut butter and his pants around his ankles at one of his meat packing facilities in Franklin Pennsylvania. When later asked by authorities what drove him to sexually assault his 4 legged companion he simply responded "the dog is so ******* hot."

The title of the article which exposed Oscar Mayer was "Hot Dog" and the rest is history. Great question!

Does this include all dogs who happen to be hot or just female canines in heat? And wouldn't it also apply to the male doggies lusting after the hot female babes?

Actually, the hot dog got it's Americanized nickname because they resemble the elongated Wiener dog breed in both shape and color. A 'hot' dog was originally called a wiener and still is in standard packaging and advertisements. Although wieners are precooked before being packaged the 'hot' part in the nickname comes from the 'dog' being re-heated to serve,

It all started at Yale, Puppy. Wasn't your Dad a Bulldog?

How silly! It's pork leftovers combined with by products all rolled in to one. I like mine cold!