Trio, a novel bovine high fecundity allele: III. Acquisition of dominance and ovulatory capacity at a smaller follicle size. Biol Reprod 2018 Mar 01;98(3):350-365
Date
02/10/2018Pubmed ID
29425314DOI
10.1093/biolre/iox157Scopus ID
2-s2.0-85050768815 (requires institutional sign-in at Scopus site) 23 CitationsAbstract
The acquisition of dominance and ovulatory capacity was evaluated in follicles from cows that were carriers or half-sibling noncarriers of the Trio allele. Follicle size at acquisition of follicular dominance was determined by evaluating whether follicles ovulate after GnRH challenge (ovulatory capacity-experiment 1) and by determination of intrafollicular concentrations of estradiol and free insulin like growth factor 1 (IGF1) and relative mRNA expression of cytochrome P450 family 19 subfamily A member 1 (CYP19A1), luteinizing hormone/choriogonadotropin receptor (LHCGR), and pappalysin 1 (PAPPA, previously known as pregnancy-associated plasma protein A, pappalysin 1) in granulosa cells from follicles of different sizes (experiment 2). Ovulatory capacity developed in follicles at 8.3 mm (50% ovulatory capacity) in noncarriers but at smaller sizes (5.5 mm) in Trio carriers. Similarly, in experiment 2, follicles of Trio carriers acquired a dominant phenotype, as determined by intrafollicular estradiol and CYP19A1, LHCGR, and PAPPA mRNA expression in granulosa cells, at significantly smaller sizes but at a similar time after wave emergence. Overall, dominance/ovulatory capacity was acquired when follicles of Trio carriers were ∼30% the size (volume basis) of follicles in noncarriers. In addition, follicles in Trio carriers appear to acquire dominance in a hierarchal manner, as demonstrated by the progressively greater number of follicles with a dominant phenotype between days 2 and 4 after wave emergence. Thus, results from this study provide further support for a physiological model in which selection of multiple follicles in Trio allele carriers is characterized by acquisition of dominance at a smaller follicle size but at a similar time in the follicular wave with multiple follicles acquiring dominance in a hierarchal sequence.
Author List
García-Guerra A, Canavessi AMO, Monteiro PLJ Jr, Mezera MA, Sartori R, Kirkpatrick BW, Wiltbank MCAuthor
Test W. User test user title in the Anesthesiology department at University of Wisconsin - MilwaukeeMESH terms used to index this publication - Major topics in bold
AllelesAnimals
Aromatase
Cattle
Estradiol
Female
Fertility
Follicle Stimulating Hormone
Granulosa Cells
Ovarian Follicle
Ovulation
Pregnancy-Associated Plasma Protein-A
Receptors, LH
