How does a rat rot? - briefly
After death, the rat’s tissues undergo autolysis and are colonized by bacteria and fungi that convert proteins and fats into gases, liquids, and simple compounds. The decomposition proceeds from internal organs outward, typically completing within weeks under normal environmental conditions.
How does a rat rot? - in detail
The decomposition of a rat proceeds through a series of predictable biological and chemical stages. Immediately after death, blood circulation ceases, and oxygen deprivation triggers cellular breakdown. Enzymes released from lysosomes initiate autolysis, causing tissue softening within minutes to a few hours.
Bacterial proliferation follows, driven primarily by gut microbiota that migrate into surrounding tissues. These microorganisms produce proteolytic and putrefactive compounds, generating characteristic odors and accelerating tissue liquefaction. The most active bacterial groups include Clostridium, Proteus and Bacteroides species.
Environmental conditions modulate the rate of decay:
- Temperature – higher ambient heat increases enzymatic activity and bacterial growth, shortening the overall process.
- Moisture – sufficient humidity supports microbial metabolism; dry conditions slow progression.
- Exposure – open air promotes oxidation and insect colonization, whereas burial or water immersion alters oxygen availability and microbial composition.
Insects contribute significantly during the later phases. Blowflies lay eggs on the carcass within hours; larvae feed on decaying tissue, converting solid matter into liquid waste and accelerating mass loss. Subsequent beetle species, such as Dermestidae, consume remaining dry tissues.
Chemical changes accompany the biological processes. Proteins break down into amino acids, which deaminate to produce ammonia, sulfides and organic acids. Lipids undergo hydrolysis, releasing fatty acids that further contribute to odor. Eventually, the skeleton, composed mainly of bone mineral, persists until environmental factors cause mineral dissolution or mechanical breakdown.
The complete transition from fresh carcass to skeletal remnants typically spans several weeks under temperate conditions, but can be compressed to days in warm, moist environments or extended to months in cold, dry settings.