The growth, size, and fat reserves of the raccoon dog Nyctereutes procyonoides (Gray, 1834) were studied in Finland in period 1986 - 1990. There was no sexual dimorphism in mean body size. Juveniles reached the mean adult body length at the age of 5 - 7 months. The weather in spring seemed to cause both annual and regional variation in the weight and fat reserves of juveniles in late autumn. Some of these differences could be seen as late as the following March, the breeding season of raccoon dogs. The adults had the least fat reserves in May and the most in October — November. The abundance of food, especially that of voles in early spring, seemed to affect the fat reserves of adult females in March.
We studied the autumn migration of the European robin (Erithacus rubecula) through north-eastern Poland. During the study period 2002–2004 we analysed a total of 2375 individuals: 1991 first-year birds and 349 adults. First-year birds had shorter wings than adults. Body condition was influenced by age, year of migration fat content and arrival time. Our results show that first-year birds arrived earlier, had low-fat levels and were in a comparatively poorer body condition to that of the adults and were less effective foragers. Stopover length decreased during the migration season for both age groups as a result of rush to their wintering areas because of winter approach. We found that adult females arrived later than adult males.
The incidence of obesity is rapidly increasing all over the world in epidemic proportions.The epidemia now affects young children and accumulative evidences suggest that the origin of the disease may occur during foetal development and early life. This has introduced the concept of "developmental programming" supported by experimental studies in animal models and numerous epidemiological data. This concept supports the idea that nutritional and hormonal status during pregnancy and early life could interfere irreversibly on the development of the organs involved in the control of food intake and metabolism and particularly the hypothalamic structures responsible of the establishment of the ingestive behaviour and regulation of energy expenditure. The mechanisms responsible of this developmental programming remain poorly documented. However ,recent research indicate that the adipokine leptin plays a critical role in this programming.