Guinea pigs vs degus and hay: a study compares how they digest fiber
Published by Planète Pets · managing editor: Clément Lacaille · how our guides are written
Hay sits at the center of both a guinea pig's and a degu's diet, but that does not mean the two species get the same benefit from it. A comparative physiology study looked into exactly what happens between intake and excretion. Our other feeding guidance is gathered in the rodent food section.
Contents · 5 sections
Three species, one shared measurement protocol
Sakaguchi and Ohmura published a 1992 study in Comparative Biochemistry and Physiology comparing fiber digestibility and digesta retention time in three small herbivorous mammals: the guinea pig, the degu, and the leaf-eared mouse, a South American species related to the degu. All three species were fed the same high-fiber diet, allowing a direct comparison of digestive efficiency rather than the effect of a different food.
The guinea pig retains and digests the longest
Result: fiber digestibility and gut transit retention time were highest in the guinea pig, intermediate in the degu, and lowest in the leaf-eared mouse. The authors link this gradient to the body mass of the three species: a larger animal generally has a proportionally roomier digestive tract, which slows transit and gives cecal microorganisms more time to extract energy from fiber.
What this means at the food bowl
This gap in digestive physiology does not overturn the rule shared by both species: constant access to good-quality hay, as our guide on hay for guinea pigs and chinchillas already covers. It does, however, help explain why the same hay does not necessarily have the same effect on both species: the guinea pig, which retains food in the gut longer, extracts more from each mouthful, while the degu, with faster transit, depends more on frequent, steady access than on one large amount available at a single moment. This lines up with guidance already given in our guide on degu food choices: how consistently hay is available matters as much as its quality.
The study's limits
The study dates from 1992 and relies on a small sample of laboratory animals, using a marker-based transit measurement that does not necessarily reflect the individual variation seen in a pet guinea pig or degu, whose diet and activity differ from a standardized experimental setting. It also does not include the chinchilla, a third species in our corpus just as dependent on hay, which limits how directly its conclusions extend beyond these two species.
Frequently asked questions
Should a degu get more hay than a guinea pig?
The study does not set a precise amount, but it suggests a degu benefits more from frequent, steady access, while a guinea pig extracts more energy from the same amount thanks to slower transit.
Does a chinchilla follow the same digestive pattern?
This study did not test that directly, but a chinchilla shares the same dependence on constant hay access with the other two species. Find all our guides on the rodent hub.
An accessory from our shop for this use: Wooden hay rack with tray for rabbit, guinea pig and chinchilla (€21.90) · the whole shop
This guide is part of Planète Pets’s Rodents universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.
