Hi and welcome
Can you please check which part of the body the clicking sound is coming from?
If it is from the mouth area - which in your case is most likely as you are hearing the clicking whenever your piggy is moving their mouth - then you are rather looking at a potential dental overgrowth issue of some sort, most likely with the grinding back teeth.
When you are checking, you could also have a peek at the edges of your self-sharpening front teeth, which do the picking up and cutting of the food:
- if they are nicely even and horizontal, then chances are that there is also no problem at the back where you cannot see.
- if the edge is slanted, then that points towards one-sided chewing and a pain issue in either incisor root or a premolar/molar root at the back.
- a jagged edge points towards uneven chewing
- a v-shaped indentation usually means restricted jaw movement
- the edges of the front teeth pointing inwards and no longer meeting is a sign of badly overgrown back teeth
This system is not perfect but it can give you an idea what you could be dealing with.
The much less likely cause of clicking, where it is constant and coming from the chest can in your case rather be ruled out - that would be the alarm sign for pneumonia and a life or death emergency.
Please switch from weighing once weekly to weighing daily first thing on your normal kitchen scales in the morning for best day to day comparison in order to monitor the food intake. Hay is making over three quarters of the daily food intake (it is actually the abrasive silica in the grass fibre against which the fast dental growth rate of guinea pigs has evolved against), but unfortunately you cannot control the all important hay intake by eye. Hay is also usually the first food group that is impacted if there is a problem with the teeth, which is resulting in weight loss and which requires appropriate fibrous support feeding.
Weight and Weight Loss Explained: BMI, Weighing, Poos and Feeding Support Levels
Please see a vet next week, preferably one with guinea pig experience for a check if the clicking persists and keeps coming from the mouth.
Wishing you all the best.
