Many tiny hair-like cilia protrude from the olfactory receptor cell's dendrite into the mucus covering the surface of the olfactory epithelium. The surface of these cilia is covered with olfactory receptors, a type of G protein-coupled receptor.
Respiration -10 to 30. The normal respiratory rate for dogs is 16 to 20 breaths per minute. The normal heartrate is 70 to 160 bpm. Large dogs tend to have slower heart rates so your dog should be in the 70 to 120 bpm range. This varies according to the cardiovascular fitness of the dog, too.
There are a few reasons why your dog may be breathing fast including pain or the lack of sufficient oxygen. The normal breathing rate of a dog is between 12 to 20 times per minute. When a dog is in pain, he may be breathing faster than usual. Even if dogs tend to hide pain, fast rate breathing may point that the dog is suffering. You should take a look at your petâs body and check for visible injuries; you should also check the mouth and the nasal passages.