title: Spontaneous activity and food requirements for maintenance and for growth in the genetically obese Zucker rat.
abstract: This study was undertaken in order to elucidate whether, as compared with those of their lean controls, the low maintenance requirements of genetically obese Zucker rats may be explained by a lower spontaneous activity. In 6 obese and 6 lean rats, daily body weight, food intake and spontaneous activity were recorded during 6 weeks, using a seismographic recorder. The obese rats weighed more (average + 46%) and ate more (average + 42%) than the lean rats, while there was no difference between their daily activity levels. The relationship between food intake (FI) and weight gain (delta W), both expressed per 100 g body weight, was: FI (kcal/day) = 3.3 delta W (g/day) + 20.4 for lean rats and 4.9 delta W (g/day) + 17.4 for obese rats. Thus, the food requirements for maintenance obtained for delta W = O was less than for obese than for lean rats, while for a given gain in body weight, it was higher for obese rats. This did not seem to be because of a lower daily activity level in the obese than in the lean rats.
mesh_terms: D000818:Animals; D001835:Body Weight; D002940:Circadian Rhythm; D004032:Diet; D004734:Energy Metabolism; D006128:Growth; D008297:Male; D009043:Motor Activity; D009751:Nutritional Requirements; D009765:Obesity / Q000235:genetics / Q000503:physiopathology*; D051381:Rats; D011924:Rats, Zucker