Physiological basis of Eimeria tenella-induced mortality in individual chickens.

Chickens dying from Eimeria tenella infection revealed four major physiological stresses before death: (1) hypothermia, (2) depletion of carbohydrate stores, (3) metabolic acidosis, and (4) renal tubule-cell dysfunction. These stresses were less pronounced in chickens surviving the infection. Similar stresses could not be demonstrated in pair-feeding trials, in which uninfected chickens were fed only the amount consumed by infected chickens. Prolonged starvation of uninfected chickens only slightly altered the indicators used in assessing the stresses. The variability of previously reported plasma glucose values, in part, may be due to whether the birds tested were those on the verge of death or those that, ultimately, would survive the infection.