"Like a dog" is "como perro" or "como un perro." You need to make the context clear, because that's the same spelling and pronunciation as "I eat dog."
No me gusta perro
tu=your Example: me gusta tu perro i like your dog.
perro
Perro.
A mi me gusta jugar con mis perros.
To say My dog likes to eat dog food in Spanish, is:Mi perro gusta comer alimentos para perros.
Me falta un perro is the best way to say "I am missing a dog" in Spanish.
Uno (the number 1) Un (used to say something like "one/a dog", "un perro")
Tu cara se parece a un perro.
perrito
perra
Mi perro.