How does rat poison work on mice? - briefly
Rat poison contains anticoagulant agents that block vitamin K recycling, preventing blood clot formation and leading to internal bleeding. After ingestion, the mouse experiences progressive hemorrhage that typically results in death within a few days.
How does rat poison work on mice? - in detail
Rodenticide formulations intended for mice commonly contain anticoagulant compounds that act as vitamin K antagonists. After ingestion, the toxin is absorbed through the gastrointestinal tract and enters the bloodstream, where it distributes to the liver, the primary site of clotting factor synthesis.
The active ingredient binds to the enzyme «vitamin K epoxide reductase», preventing regeneration of reduced vitamin K. This inhibition blocks the γ‑carboxylation of clotting proteins, specifically factors II, VII, IX and X. As a result, newly synthesized clotting factors remain inactive, while previously formed factors are gradually cleared from circulation.
The physiological consequences unfold over several days:
- Decline of functional clotting factors below a critical threshold.
- Impaired formation of fibrin clots.
- Spontaneous internal bleeding in organs such as the lungs, liver and gastrointestinal tract.
- Progressive hypovolemia leading to death.
Clinical signs observed in affected mice include lethargy, pale mucous membranes, abdominal distension, and sudden collapse. The delayed onset of mortality reduces bait aversion, increasing the probability of a lethal dose being consumed.
Resistance to anticoagulant rodenticides arises from mutations in the gene encoding the target enzyme, diminishing binding affinity. Populations with documented resistance may require alternative agents, such as non‑anticoagulant toxins that disrupt neuronal transmission or metabolic pathways.
Secondary poisoning risk exists when predators or scavengers ingest contaminated carcasses. Toxicokinetic studies show that tissue residues persist long enough to cause sub‑lethal or lethal effects in non‑target species, necessitating strict placement of bait stations and proper disposal of dead rodents.
Effective dosing relies on delivering a quantity that exceeds the lethal dose 50 % (LD₅₀) for the target species while minimizing exposure to non‑target organisms. Manufacturers provide recommended concentrations, typically expressed in milligrams of active ingredient per kilogram of bait, calibrated to achieve rapid uptake without causing immediate aversion.
In summary, mouse‑specific anticoagulant rodenticides function by interrupting vitamin K recycling, leading to a cascade of clotting deficiencies, internal hemorrhage, and eventual death. Understanding the biochemical target, resistance mechanisms and ecological implications informs responsible use and management of these control agents.