Final answer:
Ruminants experience continuous gluconeogenesis due to high levels of glucocorticoid hormones, which stimulate the liver to produce glucose from non-carbohydrate sources to maintain blood glucose levels.
Step-by-step explanation:
Ruminants are in a continuous state of gluconeogenesis primarily because of relatively high circulating concentrations of glucocorticoid hormones. These hormones, including cortisol, corticosterone, and cortisone, play a crucial role in increasing blood glucose levels to maintain levels within a normal range, especially during periods when dietary carbohydrate intake is low, such as between meals or during fasting. Glucocorticoids stimulate key processes in the liver such as the synthesis of gluconeogenic enzymes and the conversion of gluconeogenic amino acids to pyruvate, enhancing glucose synthesis from non-carbohydrate sources. In ruminants, which are continual feeders, this process is essential to maintain glucose levels for their energy needs, particularly because their diet consists largely of cellulose, which is not directly digestible into glucose.