Is the onset of obesity in suckling fa/fa rats linked to a potentially larger milk intake?. Buchberger, Petra, and Ingrid Schmidt. W.G. Kerckhoff-Institut, Max-Planck-Institut f[umlaut]ur physiologische und klinische Forschung, Parkstr. 1, D-61231 Bad Nauheim, FRG
APStracts 3:0167R, 1996.
We wanted to find out whether fatty (fa/fa) sucklings show abnormal intake when given access to an abundant milk reservoir. To do this we gravimetrically determined the milk ingested by small groups (4-5 pups) of 5- to 15-day-old lean (+/fa) and fatty littermates allowed to suckle for 30 min after their mother had not been nursing for periods between 1 and 7 h. The pups were grouped randomly and their phenotypes retrospectively identified. Within both genotypes, the intakes of simultaneously tested pups were significantly higher in pups deprived for longer periods. Deprived and undeprived fa/fa pups ingested, however, slightly but significantly less milk than +/fa littermates did in the same nursing bout. In the first two weeks of life - when fa/fa pups deposit nearly twice as much body fat as their +/fa littermates do - fa/fa pups will thus suckle less rather than more milk. This extends previous findings showing that the onset of fa/fa obesity is independent of larger intakes and thus questions that fa impairs a receptor primarily controlling food intake.

Received 30 May 1995; accepted in final form 27 February 1996.
APS Manuscript Number R325-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 8 May 96