Yes of course, it's possible for a dog to be killed by ticks. Everything depends on how bad the infestation was on the dog. If it's critical, the dog may likely die if not treated early. 

Posted by: @flint

↑

Yes, they can. Ticks transmit dangerous diseases like ehrlichiosis, babesiosis, or Lyme that can become life-threatening if not caught early. Heavy infestations can also cause severe anemia. 

Lyme is a very dangerous diseases but I didn't know that it can kill a dog. The lyme causes the skinny nature of the dog because of loss of blood by the ticks. It's very important for dog owners to be watchful of their pets.