Journal of Animal Science, Vol 69, Issue 1 194-200, Copyright © 1991 by American Society of Animal Science

JOURNAL ARTICLE

Effects of increased dietary energy and protein during late gestation on mammary development in gilts

W. C. Weldon, A. J. Thulin, O. A. MacDougald, L. J. Johnston, E. R. Miller and H. A. Tucker
Dept. of Anim. Sci., Michigan State University, E. Lansing 48824.

Thirty-two gilts were used to evaluate the effects of increased dietary energy and CP during late gestation on mammary development. On d 75 of gestation, gilts were assigned randomly in a 2 x 2 factorial arrangement to adequate (5.76 Mcal ME/d) or increased (10.5 Mcal ME/d) energy and adequate (216 g CP/d) or increased (330 g CP/d) protein. On d 105 of gestation, gilts were slaughtered and total mastectomies were performed. Mammary tissue was separated into mammary parenchymal and mammary extraparenchymal stromal tissue and analyzed for DNA, RNA, protein and lipid. No interactions between dietary energy and protein level were detected (P greater than .20). When adjusted for number of mammary glands and maternal BW (weight of the sow less the weight of the fetuses), mammary parenchymal weight was 27% greater (P less than .03) in gilts fed adequate energy than in gilts fed increased energy, but mammary extraparenchymal stroma weight was unaffected by dietary energy level. Total mammary parenchymal DNA was 30% greater in gilts fed adequate energy than in gilts fed increased energy (P less than .03). Total mammary parenchymal RNA (P less than .02) and total mammary parenchymal protein (P less than .02) also were greater in gilts fed adequate energy than in gilts fed increased energy. Dietary protein level did not affect mammary variables measured, except that increased dietary protein tended to reduce mammary extraparenchymal stromal weight (P less than .09). Increased dietary protein between d 75 and d 105 of gestation did not benefit mammary development, but increased dietary energy was detrimental to development of mammary secretory tissue.

This article has been cited by other articles:

				R. D. Mateo, J. A. Carroll, Y. Hyun, S. Smith, and S. W. Kim Effect of dietary supplementation of n-3 fatty acids and elevated concentrations of dietary protein on the performance of sows J Anim Sci, March 1, 2009; 87(3): 948 - 959. [Abstract] [Full Text] [PDF]

				F. Ji, W. L. Hurley, and S. W. Kim Characterization of mammary gland development in pregnant gilts J Anim Sci, March 1, 2006; 84(3): 579 - 587. [Abstract] [Full Text] [PDF]

				F. Ji, G. Wu, J. R. Blanton Jr., and S. W. Kim Changes in weight and composition in various tissues of pregnant gilts and their nutritional implications J Anim Sci, February 1, 2005; 83(2): 366 - 375. [Abstract] [Full Text] [PDF]

				C. Farmer, D. Petitclerc, M. T. Sorensen, M. Vignola, and J. Y. Dourmad Impacts of dietary protein level and feed restriction during prepuberty on mammogenesis in gilts J Anim Sci, August 1, 2004; 82(8): 2343 - 2351. [Abstract] [Full Text] [PDF]

				L. A. Averette, J. Odle, M. H. Monaco, and S. M. Donovan Dietary Fat during Pregnancy and Lactation Increases Milk Fat and Insulin-Like Growth Factor I Concentrations and Improves Neonatal Growth Rates in Swine J. Nutr., December 1, 1999; 129(12): 2123 - 2129. [Abstract] [Full Text]