Effect of Starvation and Refeeding on Some Liver and Blood Constituents of Atlantic Cod (Gadus morhua L.)

Abstract

Changes in body weight, liver weight, liver glycogen, blood plasma pH, hematocrit, plasma protein, and glucose levels in the Atlantic cod (Gadus morhua L.) during feeding, fasting, and liver regeneration are recorded. Resting liver glycogen content (37 ± 7 mg/100 g liver) is much lower than in many terrestrial and freshwater vertebrates. There is a transient increase in liver glycogen (702 ± 188 mg/100 g liver) with resumed feeding after prolonged fasting. Average resting levels of plasma protein (4.66 ± 0.36% w/v), glucose (100 ± 4 mg/100 ml plasma) and hematocrit (23.2 ± 1.2% v/v) decreased during the initial stages of food depletion. A reversal of this trend resulting in apparent increased levels is observed in acute malnutrition. This is attributed to dehydration of plasma with consequent drop in the total blood volume. The steady increase in plasma pH (7.24–7.54) with the duration of fasting may be due to extensive deamination of tissue protein amino acids for gluconeogenesis.