| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Journal of Animal Science, Vol 76, Issue 8 2169-2176, Copyright © 1998 by American Society of Animal Science
JOURNAL ARTICLE |
N. J. Biensen, M. E. Wilson and S. P. Ford
Department of Animal Science, Iowa State University, Ames 50011-3150, USA.
Straightbred Yorkshire (Y) conceptuses are larger than straightbred Meishan (M) conceptuses throughout gestation and at farrowing. In contrast, when Y and M conceptuses were gestated together in Y recipient females, the birth weight of M pigs was similar to that of their Y littermates. Even though placentae of M pigs remained markedly smaller than placentae of Y littermates, they were significantly more vascular. The objective of this study was to compare and contrast the changes in Y and M conceptus growth and placental-endometrial vascularity throughout late gestation in Y or M uteri. Gravid uteri were recovered at slaughter from M and Y females that were gestating either M or Y conceptuses on d 70, 90, or 110 of gestation. Uterine and conceptus measurements were recorded, and a section of the intact endometrial-placental attachment site for each conceptus was fixed, embedded, and later evaluated for placental and endometrial vascular density. Placental surface area and weight were greater (P < .001) when M or Y conceptuses were recovered from Y uteri compared with M uteri on each day of gestation examined. Further, by d 110, the surface area of Y placentae was greater (P < .001) than that of M placentae, regardless of uterine type in which they were gestated. The vascular density of M placentae and adjacent endometrium doubled (P < .05) between d 70 and 110 of gestation (3.0 and 2.5 vs 6.0 and 5.1%, respectively), with no significant increase in placental surface area. In contrast, the surface area of Y placentae doubled in size (P < .001) between d 90 and 110 of gestation, but placental and adjacent endometrial vascular density remained relatively constant, averaging 3.2 and 3.8%, respectively. These data are consistent with the premise that placental size is largely determined by the uterus in which a conceptus is gestated until approximately d 90. After d 90, fetal breed-specific mechanisms maintain optimal fetal growth. Between d 90 and term, M fetal growth depends on progressive increases in placental blood vessel density and requires no increase in placental size. In contrast, Y conceptuses seem to rely exclusively on placental growth to increase placental-endometrial surface area for nutrient exchange.
This article has been cited by other articles:
|
|
 |
|
  J. L. Vallet and B. A. Freking Differences in placental structure during gestation associated with large and small pig fetuses J Anim Sci, December 1, 2007; 85(12): 3267 - 3275. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Ptak, K. Matsukawa, C. Palmieri, L. D. Salda, P. A. Scapolo, and P. Loi Developmental and functional evidence of nuclear immaturity in prepubertal oocytes Hum. Reprod., September 1, 2006; 21(9): 2228 - 2237. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. P. Reynolds, J. S. Caton, D. A. Redmer, A. T. Grazul-Bilska, K. A. Vonnahme, P. P. Borowicz, J. S. Luther, J. M. Wallace, G. Wu, and T. E. Spencer Evidence for altered placental blood flow and vascularity in compromised pregnancies J. Physiol., April 1, 2006; 572(1): 51 - 58. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Tayade, G. P. Black, Y. Fang, and B. A. Croy Differential Gene Expression in Endometrium, Endometrial Lymphocytes, and Trophoblasts during Successful and Abortive Embryo Implantation J. Immunol., January 1, 2006; 176(1): 148 - 156. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S C Town, C T Putman, N J Turchinsky, W T Dixon, and G R Foxcroft Number of conceptuses in utero affects porcine fetal muscle development Reproduction, October 1, 2004; 128(4): 443 - 454. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. A. Vonnahme and S. P. Ford Differential Expression of the Vascular Endothelial Growth Factor-Receptor System in the Gravid Uterus of Yorkshire and Meishan Pigs Biol Reprod, July 1, 2004; 71(1): 163 - 169. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Moce, M. A. Santacreu, A. Climent, and A. Blasco The effect of divergent selection for uterine capacity on fetal and placental development at term in rabbits: Maternal and embryonic genetic effects J Anim Sci, April 1, 2004; 82(4): 1046 - 1052. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. A. Vonnahme and S. P. Ford Placental vascular endothelial growth factor receptor system mRNA expression in pigs selected for placental efficiency J. Physiol., January 1, 2004; 554(1): 194 - 201. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Vallet, H. G. Klemcke, R. K. Christenson, and P. L. Pearson The effect of breed and intrauterine crowding on fetal erythropoiesis on day 35 of gestation in swine J Anim Sci, September 1, 2003; 81(9): 2352 - 2356. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. A. Vonnahme, B. W. Hess, T. R. Hansen, R. J. McCormick, D. C. Rule, G. E. Moss, W. J. Murdoch, M. J. Nijland, D. C. Skinner, P. W. Nathanielsz, et al. Maternal Undernutrition from Early- to Mid-Gestation Leads to Growth Retardation, Cardiac Ventricular Hypertrophy, and Increased Liver Weight in the Fetal Sheep Biol Reprod, July 1, 2003; 69(1): 133 - 140. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Argente, M. A. Santacreu, A. Climent, and A. Blasco Relationships between uterine and fetal traits in rabbits selected on uterine capacity J Anim Sci, May 1, 2003; 81(5): 1265 - 1273. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Mesa, T. J. Safranski, R. K. Johnson, and W. R. Lamberson Correlated response in placental efficiency in swine selected for an index of components of litter size J Anim Sci, January 1, 2003; 81(1): 74 - 79. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. I. Leenhouwers, E. F. Knol, P. N. de Groot, H. Vos, and T. van der Lende Fetal development in the pig in relation to genetic merit for piglet survival J Anim Sci, July 1, 2002; 80(7): 1759 - 1770. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Engelhardt, B. A. Croy, and G. J. King Conceptus Influences the Distribution of Uterine Leukocytes During Early Porcine Pregnancy Biol Reprod, June 1, 2002; 66(6): 1875 - 1880. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Engelhardt, B. A. Croy, and G. J. King Evaluation of Natural Killer Cell Recruitment to Embryonic Attachment Sites During Early Porcine Pregnancy Biol Reprod, April 1, 2002; 66(4): 1185 - 1192. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
