Every tooth a degu owns grows throughout his life — the incisors at the front and the cheek teeth further back — and in a balanced mouth the side-to-side grinding of long hay keeps them all worn to an even length. Age disturbs that balance. One side of the jaw may wear faster than the other, chewing pressure shifts, and edges or points form where the grind no longer reaches evenly. Your degu cannot report a sore mouth, so his eating has to speak for him, and it does — in details that are easy to track once you know which ones matter.
Hay intake is the first thing that changes
Hay is both his main food and his dental workout, so it is the first place uneven wear shows. Notice how much of the rack he actually gets through each day compared with his usual amount, and whether he pulls strands out, mouths them and drops them rather than eating. A degu who still hurries to the hay but leaves most of it scattered is telling a different story from one who has lost interest in food altogether. Check, too, whether the hay he does eat takes visibly longer to disappear, and keep offering the longest, coarsest strands you have, since those demand the fullest grinding motion from the whole jaw.
How he handles food tells you more than appetite
Watch how he manages items of different textures, because uneven cheek teeth change his choices before they change his appetite. He may start refusing hard pieces he once crunched happily, pick out the softest leaves first, or carry food to a corner and work on it for far longer than usual. Chewing mostly on one side, dropping half-chewed food, and a damp chin after meals are all worth noting; so is pawing at the side of his mouth or leaving pellets he normally finishes. None of these proves a dental problem on its own, but a cluster of them appearing together is a pattern a vet will want described in exactly those terms.
Weight and droppings confirm the story
Impressions sharpen into evidence when you add two simple measures. Weigh him weekly, at the same time of day and before a feed, on a small kitchen scale, and write the figure down — a slow slide that is invisible in the hand becomes obvious across a month of notes. Alongside the weight, glance at his droppings when you clean the cage: a degu eating less fibre produces droppings that are smaller, darker and fewer. If the bowl still looks busy but the droppings are shrinking and the weight is drifting down, he is taking in less than his behaviour suggests, and that gap is the clearest signal monitoring can give you.
Making meals easier while you monitor
While you watch, small changes can keep eating comfortable without masking what is happening. Offer hay in more than one spot so he does not have to climb or push in for it, refresh it little and often so it smells fresh, and keep his usual foods in their usual form rather than softening everything — a sudden all-soft menu removes the very wear his teeth still need, and it hides the texture clues you are monitoring. Keep the notes brief and factual: what he refused, what he finished, the weight, the droppings. That running record turns a vague worry into something a vet can act on quickly.
The point where monitoring becomes a vet visit
Book a vet visit promptly if he stops eating hay altogether, develops a persistently wet chin, loses weight across two weekly checks, or produces very few droppings — a degu's digestion depends on constant fibre moving through, so eating that stalls is never a wait-and-see matter. Only a vet can examine the cheek teeth properly and even out what age has worn unevenly. Recording each week's findings in KinsLe's Pet Passport means the weight trend, the refused foods and the droppings notes arrive at that appointment as one organised packet instead of a half-remembered summary.