No Breakfast? physiological effects of morning food deprivation in spotted munia (Lonchura punctulata)

Abstract

Food is essential for an organism to meet its daily energy requirements. For this reason, animals show a highly motivated behaviour towards the acquisition of food. Food availability, however, is fairly irregular in nature as it is influenced by a number of environmental and ecological factors. Hence, food availability is a key factor in shaping the life history of an organism. In the present study, we tested the effects of timed food restriction on behaviour, physiology and hormone levels in Spotted Munia (Lonchura punctulata) subjected to a food availability for only four hours in the evening (Food restriction- FR). We also measured the indicators of stress to assess how birds responded to the restricted feeding schedule. The birds showed a significant change in their daily activity rest pattern where FR birds showed minimum movement during the time window when food was made available to them. Further, after two weeks, we found a lower body weight, plasma T3 and cort levels in FR birds, as compared to ad libitum controls. While the Heterophil/Lymphocyte ratio was higher, we observed a lower spleen weight and size in FR birds. These findings suggest that a predictable food scarcity led to behavioural and physiological adjustments in munia(s) reflective of an adaptive energy reallocation during food restriction.