Why do rats eat their own feces? - briefly
«Rats practice coprophagy to reclaim essential nutrients, vitamins (especially B12), amino acids, and beneficial gut microbes that were not absorbed during the initial digestion». This behavior enhances growth, health, and overall digestive efficiency.
Why do rats eat their own feces? - in detail
Rats regularly engage in coprophagy, the consumption of their own fecal material, to obtain nutrients that are not fully absorbed during the first passage through the gastrointestinal tract. The process occurs primarily in the cecum, where microbial fermentation converts indigestible fibers into short‑chain fatty acids, vitamins and amino acids. Reingestion allows rats to retrieve these products before they are expelled.
Key physiological benefits include:
- Recovery of B‑group vitamins, especially cobalamin (B₁₂) and biotin, synthesized by cecal bacteria;
- Absorption of volatile fatty acids such as acetate, propionate and butyrate, which serve as energy sources;
- Acquisition of essential amino acids and nitrogenous compounds produced by microbial proteolysis;
- Maintenance of a balanced gut microbiome by re‑seeding the distal intestine with beneficial microbes.
Developmental considerations influence the frequency of this behavior. Neonatal and juvenile rats exhibit higher rates of coprophagy because their digestive systems are still maturing and rely heavily on microbial contributions for growth. Adult rats continue the practice at reduced levels to sustain nutrient balance.
Environmental and health factors can modify the pattern. Limited dietary protein, low vitamin content, high fiber intake, or stressors such as overcrowding increase the drive to ingest feces. Conversely, provision of a nutritionally complete diet reduces the necessity for re‑consumption.
In summary, the ingestion of self‑produced fecal material serves as a physiological adaptation that maximizes nutrient extraction, supports vitamin synthesis, and stabilizes the intestinal ecosystem, thereby contributing to overall health and survival of the species.