|
|
||||||||
Journal of Animal Science, Vol 69, Issue 1 134-145, Copyright © 1991 by American Society of Animal Science
JOURNAL ARTICLE |
M. E. White, T. G. Ramsay, J. M. Osborne, K. A. Kampman and D. W. Leaman
Dept. of Anim. Sci., Ohio State Univ., Columbus.
We investigated the effects of weaning or fasting of 21- or 35-d-old swine by monitoring serum mitogenic activity, circulating insulin-like growth factor I (IGF-I) and its binding proteins using L6 myoblast bioassays, RIA and ligand blotting techniques. Serum samples were collected from 21- or 35-d-old animals just before and 36 h after weaning or fasting. Sera from 21- and 35-d-old weaned animals were not significantly altered in their ability to promote myoblast proliferation, whereas sera from 21- and 35-d-old fasted animals caused 29 and 21% decreases (P less than .05) compared with preweaning. The mitogenic activity of control serum was inhibited by serum from fasted animals but not by preweaned or weaned sera. Serum IGF-I levels were decreased 65 to 70% (P less than .05) with weaning or fasting at both ages. Unoccupied binding sites on circulating IGF binding proteins in the 155 kDa range decreased 18 to 19% with weaning at both ages and decreased 40% (P less than .05) with fasting at 21 d but only 17% at 35 d. Ligand blotting revealed that the 43 and 39 kDa IGF binding protein bands decreased with weaning and fasting at both ages, whereas the 29-kDa band increased with weaning and fasting. These data indicate that serum IGF-I and specific IGF binding protein bands decrease during weaning or fasting at 21 and 35 d of age. However, serum mitogenic activity did not always follow serum IGF-I levels.
This article has been cited by other articles:
![]() |
B. E. Salfen, J. A. Carroll, D. H. Keisler, and T. A. Strauch Effects of exogenous ghrelin on feed intake, weight gain, behavior, and endocrine responses in weanling pigs J Anim Sci, July 1, 2004; 82(7): 1957 - 1966. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Y. Whang, S. W. Kim, S. M. Donovan, F. K. McKeith, and R. A. Easter Effects of protein deprivation on subsequent growth performance, gain of body components, and protein requirements in growing pigs J Anim Sci, March 1, 2003; 81(3): 705 - 716. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Turner, S. S. Dritz, J. J. Higgins, K. L. Herkelman, and J. E. Minton Effects of a Quillaja saponaria extract on growth performance and immune function of weanling pigs challenged with Salmonella typhimurium J Anim Sci, July 1, 2002; 80(7): 1939 - 1946. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |