| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ANIMAL GROWTH, PHYSIOLOGY, AND REPRODUCTION |
,2
,3,4
* Department of Physiology and
and
Department of Obstetrics and Gynaecology, University of Adelaide, Adelaide 5005, Australia, and
and
Research and Development Unit, QAF Meat Industries, Ltd., Redlands Road, Corowa 2646, Australia
2 Correspondence: School of Molecular and Biomedical Science (phone: +61-8-8303-4158; fax: +61-8-8303-3356; e-mail: kathy.gatford{at}adelaide.edu.au).
Abstract
Treatment of pigs with porcine ST (pST) in early to mid-pregnancy increases body weight and length of their fetuses by mid-pregnancy, but this increased weight may not persist to birth. We investigated the effects of short- (25 d) and long-term (75 d) treatment with pST, and interactions between long-term pST treatment and crude protein content of diet, in restricted-fed gilts. In both experiments, Large White x Landrace gilts were bred at first estrus to Large White x Duroc boars and allowed to farrow naturally. In the first experiment, gilts were fed 1.8 kg/d of a diet containing 13.5 MJ DE/kg of DM and 15.05% CP (as-fed basis) throughout pregnancy, and were injected daily with 0, 2, or 4 mg pST from d 25 to 50 of pregnancy. Maternal treatment with pST from d 25 to 50 of pregnancy did not affect the number of piglets born per litter or progeny size at birth. In the second experiment, gilts were injected daily with 0 or 2 mg of pST and fed 2.2 kg/d of a diet containing 14.5 MJ DE/kg and either (as-fed basis) 16.6% (0.81% lysine) or 22.2% CP (1.16% lysine) from d 25 to 100 of pregnancy. All gilts were then fed 3.0 kg/d of the lower protein diet from d 100 of pregnancy to farrowing. Treatment with 2 mg pST/d from d 25 to 100 of pregnancy increased live weight of all gilts during the treatment period (P = 0.016), but the change in maternal live weight from d 25 to 100 of pregnancy was only increased (P = 0.001) by pST in gilts fed the higher protein diet. Live weight of gilts 1 d after farrowing was increased by pST treatment (P = 0.007), but was not altered by protein content of diet during pregnancy. In gilts fed the lower protein diet, but not in those fed the higher protein diet, pST treatment decreased maternal backfat depth during treatment (P < 0.020) and 1 d after farrowing (P = 0.002). Treatment with pST during pregnancy did not affect the number of piglets born per litter but independently increased body weight by 11.6% (P < 0.001) and length by 3.4% (P = 0.005) of progeny at birth and decreased (P < 0.01) the negative effect of litter size on body weight at birth. We conclude that in feed-restricted gilts, fetal weight gains in response to 25 d of pST treatment before mid-pregnancy are not maintained to term but that treatment with pST during most of pregnancy increases progeny size at birth and reduces maternal constraint of fetal growth.
Key Words: Birth Weight • Dietary Protein • Pig • Pregnancy • Somatotropin
This article has been cited by other articles:
|
|
 |
|
  J. M. Wallace, M. Matsuzaki, J. Milne, and R. Aitken Late but Not Early Gestational Maternal Growth Hormone Treatment Increases Fetal Adiposity in Overnourished Adolescent Sheep Biol Reprod, August 1, 2006; 75(2): 231 - 239. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. E Trujillo-Ortega, D. Mota-Rojas, R. Hernandez-Gonzalez, E. Y. Velazquez-Armenta, A. A Nava-Ocampo, R. Ramirez-Necoechea, M. Becerril-Herrera, and M. Alonso-Spilsbury Obstetric and neonatal outcomes to recombinant porcine somatotropin administered in the last third of pregnancy to primiparous sows. J. Endocrinol., June 1, 2006; 189(3): 575 - 582. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Rehfeldt and G. Kuhn Consequences of birth weight for postnatal growth performance and carcass quality in pigs as related to myogenesis J Anim Sci, April 1, 2006; 84(13_suppl): E113 - E. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
