What is the only Shakespearean play that included a dog?

Crab in The Two Gentlemen of Verona

https://en.wikipedia.org/wiki/Two_Gentlemen_of_Verona#Connections_with_Shakespeare.27s_other_work

We've had this question a couple of times before, and gmack pointed out that a nameless dog does appear in "A Midsummer Night's Dream," Act V, scene i. He's described by the tailor Starveling, who is playing "Moonshine," as "this dog, my dog."

and from Macbeth..

MACBETH
Ay, in the catalogue ye go for men;
As hounds and greyhounds, mongrels, spaniels, curs,
Shoughs, water-rugs and demi-wolves, are clept
All by the name of dogs: the valued file
Distinguishes the swift, the slow, the subtle,
The housekeeper, the hunter, every one
According to the gift which bounteous nature
Hath in him closed; whereby he does receive
Particular addition.

Except, elburcher, that that passage merely refers to dogs, as do many in Shakespeare. The word "dog" shows up again and again. The question asks for a dog that actually appears in a play.

Will Kempe,who originally played many of Shakespeare's comic roles, often worked his dog into the comic business - not actually written in by William Shakespearwe, but Kempe's dog did appear in many productions!