Laboratory examination of the efficacy of sodium selenite rodenticide against wildpopulations of Norway rat (Rattus norvegicus)

Abstract: Laboratory feeding tests were carried out to determine the efficacy of sodium seleniteas a rodenticide against individually caged wild male and female Norway rats Rattus norvegicus.The experiment was conducted on 20 animals (10 males and 10 females) captured at two millingfacilities near Novi Sad, Serbia, and in compliance with the recommended OEPP/EPPOprocedure. Individual animals were acclimated to cage (120x90x45cm, l, w, h) and laboratoryconditions for 7-10 days after catching. Over the period, they had free access to unpoisoned baits,made on the same recipe as poisoned ones, only without the active ingredient. The rats wereoffered 20g of unpoisoned bait per individual and the portions were measured and refilled on adaily basis. After the period of acclimation, rats were given portions of 20g of bait containing0.1% sodium selenite. The consumed amounts of poisoned bait were measured daily and refilledwith fresh bait of identical weight. During the experiment, water was available ad libitum. Males,having 259.8±12.12g average weight, died after 8.9±0.85 days, while females with average179.1±12.65g weight died after 7.9±0.86 days. Palatability of sodium selenite was very good.