Pathophysiologic changes due to coronavirus-induced diarrhea in the calf.

Extensive water, sodium, chloride, bicarbonate, and potassium losses occur in the diarrheal calf. The water loss is entirely from the extracellular space. In severe cases, hypovolemic shock occurs with the blood volume decreased by as much as one-half. Acidosis, which results from fecal bicarbonate loss, lactic acidosis, and renal dysfunction, results in tissue buffering, which in turn causes the efflux of cellular potassium ions. Although there is a total body potassium deficit, plasma potassium concentration is increased. This, in conjunction with an intracellular deficit, causes weakness, lethargy, and potassium cardiotoxicosis resulting in death. Hypoglycemia also contributes to the weakness and lethargy seem as calves become moribund. These losses from the body and shifts in fluids and electrolytes must be understood to develop the most effective rationale for supportive therapy.