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Flender/Flender Gear Units/Bevel-helical gear reducers B4

tion is cumulative, and they need to be ingestedover period of few days or even several days to be effective. Rodents readily acceptanticoagulants in bait formulations and the problem of primary and secondary poisoning is considerably less. Vitamin is an effective antidote for anticoagulants. The rst generation anticoagu- lants such as warfarin, coumachlor, and diphacinone are known for delayed effect andneed ingestion by rats for several days; therefore they are expensive in terms of bait and labor. Resistance problem is another disadvantage with these anticoagulants. Quick-acting second-generation anticoagulants were introduced in 1s to overcome the resistance problem. They are the halogenated hydroxycoumarin derivatives, such as difenacoum and bromadiolone. Some of the anticoagulants such as brodifacoum or ocoumafen are effec- tive in single dose at 2 mg/kg. In some situations, fumigants, such as hydrocyanic acid gas and phosphine, are used for control. Burrows are treated with calcium cyanidepowder releasing hydrocyanic acid or aluminium and magnesium phosphide pellets orablets releasing phosphine gas. Fumigation of storage facilities will also eliminate rodentinfestation in addition to grain insect pests. Controlled atmospheres particularly carbon dioxide-rich atmospheres are also effective although the technique is seldom practiced against rodents (. To sum up, an integrated approach involving good housekeeping, maintenance of hygienic conditions in and around, physical means of trapping, use of poisoning by baitformulations, and burrow fumigations is essential to contain the rodent menace. As theyinvade the storage structures and migrate to new areas in search of food, continuous management program is required. 3.5 Birds The extent of losses to stored grains by birds has been less studied than that of rats. Losses result from direct feeding and from contamination by their droppings and feathers. Theiractivity starts immediately after harvest, during th