Lucilia cuprina induced hyperammonaemia and alkalosis associated with pathology in sheep

Gross and microscopical examinations were done in 12 sheep infested with Lucilia cuprina larvae. All the sheep became hyperammonaemic and alkalotic. Six sheep died and 6 survived, one being moribund before euthanasia. Necropsy revealed severe acute dermatitis and congestion of the liver, heart, kidney, spleen and lungs. Ecchymotic haemorrhages were present in the heart, kidneys and adrenal glands of severely infested sheep. Microscopical examination showed mild to severe vacuolation of the central nervous system in all sheep. In severely infested sheep, skin, lung, heart, kidney, and liver tissues were infiltrated by mononuclear cells, neutrophiles or lymphocytes. Fibrin thrombi were present in vessels. Elevated concentrations of lipid soluble ammonia in blood were positively correlated with tissue abnormality and early death.