PHYSIOLOGICAL REVIEWS
Vol. 78, No. 3 July 1998
Printed in U.S.A.

Biology of Somatotropin in Growth and Lactation of Domestic Animals

TERRY D. ETHERTON AND DALE E. BAUMAN

Department of Dairy and Animal Science,
The Pennsylvania State University, University Park, Pennsylvania;
and Department of Animal Science,
Cornell University, Ithaca, New York

I. Introduction 745
II. Structure of Somatotropin 746
III. Efficacy of Somatotropin 747
A. Growth 747
B. Lactation 748
IV. Mechanisms of Somatotropin Action 750
A. Effects on lipogenesis and lipolysis 751
B. Effects on carbohydrate metabolism 754
C. Effects on protein metabolism 755
D. Effects on mammary gland metabolism 755
V. Summary756

Etherton, Terry D., and Dale E. Bauman. Biology of Somatotropin in Growth and Lactation of Domestic Animals. Physiol. Rev. 78: 745–761, 1998.—Impressive progress has been made during the past 15 years in our understanding of the biology of somatotropin (ST) in domestic animals. In part, this progress was sparked by advances in biotechnology that made feasible the production of large quantities of recombinant bovine ST (bST) and porcine ST (pST). The availability of recombinant bST and pST resulted in an exponential increase in investigations that explored their role in growth and lactation biology, as well as evaluated their potential for commercial use. Collectively, these studies established that administration of bST to lactating dairy cows increased milk yield, and treatment of growing pigs with pST markedly stimulated muscle growth and reduced fat deposition. In addition to these ‘‘efficacy’’ studies, a substantial number of investigations examined the mechanisms by which ST affects lactation and growth of domestic animals. This review summarizes the diverse physiological effects ST has on growth and lactation and discusses the underlying mechanisms that mediate these effects in domestic animals. ….. Growth and Lactation of Domestic Animals.

Source: Department of Dairy and Animal Science
Author: TERRY D. ETHERTON AND DALE E. BAUMAN