Why does a male dog mouth tremors after licking female privates?

There are a few reasons why a male dog might mouth tremor after licking female privates.

Involuntary muscle contractions:

When a male dog licks a female's privates, it stimulates sensory receptors in the brain that triggers a reflex response in the mouth muscles. This response is characterised by involuntary muscle contractions, or mouth tremors.

Excitement:

The act of licking a female can be very stimulating for a male dog, and the excitement can cause him to tremble or shake. This excitement is often accompanied by other signs of arousal such as erection, increased heart rate and panting.

Pleasure:

Licking the female's privates can also be pleasurable for the male dog, and the tremors may be a way of expressing this pleasure or enjoyment.

Stress or anxiety:

In some cases, mouth tremors can be a sign of stress or anxiety in male dogs, however, this is less likely to be the case if the male is exhibiting signs of excitement and pleasure such as erection and panting.

If you're concerned about your dog's mouth tremors after licking female privates, it's always a good idea to talk to your veterinarian to rule out any underlying health conditions.