Pregnancy toxemia and ketosis of ewes and does.

Pregnancy toxemia of ewes and does appears to occur when the animal cannot meet the glucose demands of the fetal-placental unit and hypoglycemia develops. There is individual variation in susceptibility, and there may be basic differences in glucose metabolism between susceptible animals and nonsusceptible animals. Increased serum NEFA and ketone body concentrations accompany the disease, but clinical signs do not appear to develop in the absence of hypoglycemia. The diagnosis is based on history, clinical signs, and the finding of ketone bodies in the urine. Numerous metabolic abnormalities develop subsequent to hypoglycemia and hyperketonemia, and these affect the prognosis. Important secondary abnormalities include acidosis, dehydration, and renal failure. Therapy is frequently unsuccessful, but frequent administration of small doses of glucose appears to be beneficial, if the other abnormalities, such as acidosis and dehydration, are controlled. Prevention can be readily achieved by nutritional means and is far more rewarding than therapy. Ewes and does must be fed in relation to their changing energy needs throughout the reproductive cycle.