The pattern that matters: a change in what she picks
Every guinea pig has preferences, and a lifelong fondness for soft leaves over stalky hay is not, on its own, a warning. What should catch your attention is a shift in an individual pig's habits: the animal who used to crunch through carrot batons and coarse hay now waits for soaked pellets, picks out the softest lettuce, and leaves the fibrous foods she managed happily before. Guinea pigs' teeth — incisors at the front and cheek teeth at the back — grow throughout life and are worn down by exactly the long-strem chewing that hay and fibrous food demand. When chewing becomes uncomfortable anywhere in that system, eating around it by choosing soft food is a rational workaround, and it is often the first sign an owner can see.
Other signs that strengthen the picture
Selective eating rarely travels alone for long. Watch for food being taken into the mouth and dropped, chewing that looks slow, exaggerated or tilted to one side, and a wet chin or dribbling after eating. Check output as well as intake: fewer or smaller droppings suggest less food — especially less fibre — is actually getting through. Weigh her weekly, and ideally twice a week once you have noticed a change; a downward trend confirms the soft-food picking is costing her real nutrition. You can gently lift her lip to look at the front teeth for obvious unevenness or slanting, but the cheek teeth that do most of the grinding sit too far back to assess at home — that part belongs to a vet with proper equipment.
What not to do while you wait
It is tempting to help by softening everything — mashing pellets, dropping hay, offering only easy foods. Resist it beyond a day or so. A pig who stops chewing coarse food loses the very wear her teeth need, and low fibre intake slows her digestion, which in guinea pigs can escalate quickly. Keep fresh hay in front of her at all times even if she only picks at it, keep her usual veg coming, and offer softened food as a supplement rather than a replacement so she keeps eating something while you arrange the check. Do not attempt any home trimming or filing — teeth problems in guinea pigs are assessed and treated by a vet, full stop.
When to book, and what to bring
Book the appointment as soon as you see the pattern settle in — a pig choosing soft foods plus any one of dropping food, dribbling, weight loss or reduced droppings should be seen promptly, and a pig who stops eating altogether is urgent. Vets say the most useful thing an owner can bring is a timeline: when the food choices changed, what she still eats, what she refuses, and how her weight has moved. Reconstructing that from memory in the consulting room is unreliable, especially in a household where several people feed the pig.
Keeping the record the vet actually needs
A simple dated log — foods offered, foods refused, weekly weights, droppings normal or not — turns a vague worry into evidence a vet can act on. Holding that log in KinsLe's Pet Passport keeps it with the guinea pig's other records, so the eating notes, weight trend and any previous dental findings travel to the appointment together instead of living on scraps of paper at home.