Encapsulated zinc phosphide and its use as rodenticide

A rodenticide is described which contains encapsulated zinc phosphide as poison, a bait and a binder for achieving adherance of the encapsulated zinc phosphide to the bait. The binder contains a polyol or a sugar-containing liquid. The encapsulating agent is a thermoplastic polyamide, preferably nylon, which is present in amounts from approximately 2 to approximately 10 percent by weight based on the zinc phosphide. If the bait is cereal or a cereal product, a zinc salt is preferably added to the rodenticide to avoid the formation of phosphine. Histamine, histamine salts or histamine-forming substances such as red pepper can also be added to the rodenticide in order to stimulate gastric fluid secretion in the rodent. There is also described a particulate encapsulated product which has a zinc phosphide core and a coating composed of a thermoplastic polyamide in an amount of approximately 2 to approximately 10 percent by weight. The encapsulated product has such a small particle size that it passes a screen of light mesh size 0.42 mm (40 mesh).