Alan D. Ealy, Ph.D.

The overall goal of our research program is to elucidate the key physiological, endocrine and molecular mechanisms responsible for conceptus development and subsequent establishment and maintenance of pregnancy in ruminants.  From 20 to 40% of all fertile matings in cattle do not result in the birth of a live calf, and a majority of these losses occur within the first month of pregnancy.  Failures in conceptus elongation and maternal recognition of pregnancy undoubtedly contribute to pregnancy loss.  By improving our understanding of the basic biology of embryogenesis and placentation, management schemes can be created to reduce embryonic losses in production livestock.  Work in the laboratory focuses on two areas:     

Early Placental Development: The outer-most layer of the fetal placenta, termed the trophectoderm, undergoes extensive proliferation prior to its attachment to the uterine lining in cattle, sheep and other ruminants. After its attachment, a new cell type, the binucleate cell, emerges as the predominant endocrine cell type.  The laboratory is using a combination of in utero, in vitro and molecular technologies to identify uterine- and conceptus-derived factors that regulate the rate of trophectoderm proliferation.  We also are searching for control points in binucleate cell formation and function during early pregnancy. 

Regulation of Placental Gene Expression:  In ruminants, the developing conceptus must communicate with the maternal system to establish a uterine environment conducive for pregnancy.  Interferon-tau (IFN-t) is the hormone responsible for maintenance of pregnancy in ruminants.  It is secreted by the trophectoderm and interacts with the uterine lining to prevent corpus luteum regression and return to estrus.  The temporal and spatial expression pattern of IFN-t is well documented, but the endocrine and molecular mechanisms that regulate IFN-t gene expression remain largely undefined.  Our laboratory is identifying and characterizing uterine- and conceptus-derived factors that influence IFN-t gene expression during early pregnancy.   

Representative Publications:

Ocón-Grove O M, Cooke FN, Alvarez IM, Johnson SE, Ott TL and Ealy AD. 2008.  Ovine endometrial expression of fibroblast growth factor (FGF) 2 and conceptus expression of FGF receptors during early pregnancy. Domest. Anim. Endocrinol. 34:135-145.

Rodina TM, Cooke FNT, Hansen PJ and Ealy AD.  2008.  Oxygen tension and medium type actions on blastocyst development and interferon-tau secretion in cattle.  Anim. Reprod. Sci. Epub: 2/26/08.

Talbot NC, Powell AM, Ocón-Grove, OM, Caperna TJ, Camp M, Garrett WM and Ealy AD.  2008. Comparison of the interferon-tau expression from primary trophectoderm outgrowths derived from IVP, NT, and parthenogenote bovine blastocysts. Mol. Reprod. Dev. 75:299-308.

Cooke RF, Arthingon JD, Araujo DB, Lamb GC and Ealy AD. 2008.  Effects of supplementation frequency on performance, reproductive, and metabolic responses of Brahman-crossbred females. J. Anim. Sci. Epub: 4/25/08.

Block J, Fischer-Brown AE, Rodina TM, Ealy AD and Hansen PJ. 2007. The effect of in vitro treatment of bovine embryos with IGF-1 on subsequent development in utero to day 14 of gestation. Theriogenology 68:153-161.

Kurosaka S, Eckardt S, Ealy AD and McLaughlin KJ. 2007. Regulation of blastocyst stage gene expression and outgrowth interferon tau activity of somatic cell clone aggregates.  Cloning Stem Cells 9:630-641.