The principal objective of this study was to examine the GH-dependency of IGF-I and IGF-II
changes with undernutrition using a Laron dwarf (GH receptor deficient) chicken. Since shortterm
feed restriction of dwarf chickens resulted in decreased plasma IGF-I, although to a lesser
extent than in DW chickens, it suggests that this response is not completely GH-dependent.
However, with longer term undernutrition IGF-I was not decreased in dwarf chickens, but was
still reduced in Dw chickens which may indicate that only the GH-dependent reduction remains
present after 7 days of restriction. IGF-II was lower in dwarfs and was not depressed by feed
restriction in the dwarf chicken, suggesting that nutritionally induced changes in IGF-II are
GH-dependent.