How does poison work on rats and mice? - briefly
Rodent poisons act by disrupting essential physiological processes: anticoagulant formulations inhibit vitamin K recycling, leading to uncontrolled internal bleeding, and neurotoxic agents bind to neuronal receptors, causing paralysis and respiratory arrest. The resulting organ failure quickly proves lethal to the animal.
How does poison work on rats and mice? - in detail
Rodent toxicants act by disrupting physiological processes essential for survival. The most common categories—anticoagulants, neurotoxins, metabolic inhibitors, and gastrointestinal poisons—each target a specific system.
Anticoagulant compounds interfere with the vitamin K cycle. By binding to the enzyme vitamin K epoxide reductase, they prevent regeneration of active vitamin K, which is required for synthesis of clotting factors II, VII, IX, and X. Blood loss progresses gradually, leading to internal hemorrhage and death after several days. First‑generation agents (e.g., warfarin) require multiple feedings; second‑generation products (e.g., brodifacoum) are more potent and effective after a single ingestion.
Neurotoxic agents such as bromethalin, zinc phosphide, or organophosphates affect nerve transmission. Bromethalin uncouples mitochondrial oxidative phosphorylation, causing cerebral edema and paralysis. Zinc phosphide reacts with stomach acid to release phosphine gas, which blocks cellular respiration. Organophosphates inhibit acetylcholinesterase, resulting in excessive acetylcholine accumulation, muscle twitching, respiratory failure, and rapid death.
Metabolic inhibitors target energy production. Sodium fluoroacetate (1080) converts to fluorocitrate, which inhibits aconitase in the citric acid cycle, halting ATP synthesis. The animal experiences seizures, cardiac arrhythmia, and eventual collapse within hours.
Gastrointestinal poisons, primarily zinc phosphide and certain metal phosphides, produce severe irritation of the stomach lining. The resultant vomiting, diarrhea, and dehydration can be fatal if the dose is sufficient.
Key factors influencing efficacy include:
- Dose concentration – higher milligrams per kilogram increase lethality.
- Palatability – bait flavored with attractive ingredients promotes consumption.
- Resistance – repeated exposure to anticoagulants can select for genetic mutations in the vitamin K epoxide reductase gene, reducing susceptibility.
- Species variation – metabolic rates differ between rats and mice, affecting the speed of onset.
After ingestion, toxicants are absorbed through the gastrointestinal tract, enter the bloodstream, and distribute to target organs. The time to observable symptoms ranges from minutes (neurotoxins) to days (anticoagulants). Mortality is confirmed by post‑mortem examination revealing hemorrhage, organ congestion, or characteristic lesions depending on the poison class.