Assistant Laboratory Animal Technician (ALAT) Practice Exam

What effect can temperatures below the LCT have on animals?

1. Increased social interactions

2. Reduced metabolic rate

3. Increased energy expenditure

4. Improved immune responses

The correct answer is: Increased energy expenditure

When animals are exposed to temperatures below their Lower Critical Temperature (LCT), their bodies must work harder to maintain a stable internal temperature. This situation leads to increased energy expenditure as the animal engages in thermogenic activities to generate heat. In cold environments, animals may shiver, seek additional food to increase caloric intake, or engage in behavioral adaptations like huddling, all of which contribute to a greater demand for energy. In contrast, other choices do not accurately reflect the physiological response to cold temperatures. Increased social interactions may occur in some species but are not a direct or necessary consequence of low temperatures. A reduced metabolic rate typically occurs in warm conditions or during energy conservation phases, while improved immune responses do not generally correlate with cold stress, as prolonged exposure can actually compromise immune function. Thus, the necessary increase in thermogenesis in response to low temperatures clearly highlights why increased energy expenditure is the correct understanding of the effects of temperatures falling below the LCT.