How much poison can a rat eat? - briefly
The lethal dose of most rodenticides for a rat is approximately 0.5–1 mg per kilogram of body weight; larger amounts cause rapid death. Doses below this threshold may produce symptoms but are not immediately fatal.
How much poison can a rat eat? - in detail
Rats possess a high metabolic rate and a robust ability to tolerate certain toxins, yet the quantity of a lethal agent they can ingest varies widely with the substance’s potency, the animal’s size, and its physiological condition.
The lethal dose (LD₅₀) for common rodenticides provides a benchmark for estimating the maximum amount a typical laboratory rat (approximately 250 g body weight) can survive. For example:
- Warfarin‑based anticoagulants: LD₅₀ ≈ 150 mg/kg → about 37 mg for a 250 g rat.
- Bromadiolone (second‑generation anticoagulant): LD₅₀ ≈ 0.5 mg/kg → roughly 0.13 mg.
- Brodifacoum: LD₅₀ ≈ 0.03 mg/kg → around 0.008 mg.
- Zinc phosphide (acute toxicant): LD₅₀ ≈ 150 mg/kg → about 37 mg.
These figures represent the dose at which 50 % of test subjects die; individual rats may survive higher or lower amounts depending on age, health, and prior exposure. Sub‑lethal ingestion can cause delayed symptoms such as internal bleeding, neurological impairment, or organ failure, often culminating in death after several hours to days.
Key factors influencing the amount a rat can consume:
- Form of the poison – powders, pellets, or liquids affect palatability and absorption rate.
- Delivery method – bait laced with attractants may increase intake, while coated or hidden doses reduce it.
- Tolerance development – repeated low‑dose exposure can induce enzymatic resistance, raising the effective lethal threshold.
- Physiological state – pregnant, young, or diseased rats exhibit altered susceptibility.
In practice, pest‑control professionals calculate bait concentrations to ensure each rodent ingests at least twice the LD₅₀, accounting for variability and ensuring rapid mortality. Consequently, the precise amount a rat can eat before succumbing is not a fixed figure but a range dictated by the specific toxicant and experimental conditions.