This vitamin is necessary to maintain normal clotting mechanisms and a deficiency causes haemorrhages throughout the tissues. Low levels of vitamin K have been implicated in navel bleeding in newborn piglets although the response to the addition of 2g/tonne of vitamin K is usually disappointing. Sulphadimidine and warfarin act as vitamin K antagonists. Oral and injectable preparations of vitamin K are available as menadione bisulphate. Treatment can be given by intramuscular injection at 2.5mg/kg liveweight. (See warfarin poisoning).