DIFFERENTIAL COMPENSATORY ORGAN GROWTH IN YOUNG-PIGS AFTER SHORT-TERMREHABILITATION FROM PROTEIN-DEFICIENCY

Our objective was to determine the changes in body composition and org an mass in response to severe dietary protein restriction and short-te rm rehabilitation. Six-week-old pigs were fed ad libitum either a nutr itionally adequate (A, 21% protein, n=4) or a protein-deficient (D, 5% protein, n=4) diet for 8 week, then all pigs were fed the adequate di et for 5 week. Body weight remained less after the 5 week repletion pe riod in D pigs than in A pigs; relative weights of cerebrum, heart, sm all intestine, and large intestine, but not of stomach, liver, kidneys or spleen, were greater in D than in A pigs. Plasma total protein, al bumin, Ca, and inorganic P were depressed and plasma HDL-cholesterol a nd K were elevated by protein depletion, but restored to normal levels after 5 week of repletion. Percentage of body fat was greater and tha t of non-osseous lean was less in in D pigs after 8 week of depletion than in A pigs (dual energy x-ray absorptiometry, DXA), but values for D pigs after 5 week of repletion were similar to those of A pigs; who le body chemical analysis after repletion corroborated the terminal DX A data. Our results suggest that changes in body composition induced b y 8 week of severe protein restriction are restored after 5 week of re habilitation to values similar to those of age-matched, adequately fed pigs, and that non-allometric growth of selected organs occurs during repletion as a compensatory response in young, growing animals.