A dynamic model for ovulation rate reveals an effect of the estrogen receptor genotype on ovarian follicular development in the pig.
A mathematical model that describes the recruitment and growth of ovarian follicles was fitted to data on ovulation rate and the measurements of plasma estradiol collected at times during the estrous cycle for individual gilts. The method of least squares was used to obtain estimates of the parameters of the mathematical model. The estimated model parameters were the maximum estradiol production for a follicle, development of each follicle after commitment, and a function describing the initial estradiol production of committed follicles. The estimated parameters for each pig were classified by estrogen receptor (ER) genotype (AA or BB) and analyzed using a multivariate analysis of variance. There were differences between genotypes (P < 0.05) for the parameter that described the initial distribution of individual follicles at recruitment. Gilts with ER genotype BB recruited follicles that varied more in size but had fewer very small follicles, indicating that the ER gene affects the relative estradiol secretion of the follicles at commitment. This analysis is an example of a general approach to genetic studies that uses a mathematical model of the physiology as a statistical basis for estimating gene action.
AgResearch Ruakura, Hamilton, New Zealand. tanya.soboleva@agresearch.co.nz
T K
TK
Soboleva
A B
AB
Pleasants
B T T M
BT
van Rens
T
T
van der Lende
A J
AJ
Peterson
D000704:Analysis of Variance; D000818:Animals; D004958:Estradiol / Q000097:blood; D005260:Female; D005838:Genotype; D008433:Mathematics; D008954:Models, Biological; D006080:Ovarian Follicle / Q000254:growth & development*; D010060:Ovulation / Q000502:physiology*; D011960:Receptors, Estrogen / Q000235:genetics* / Q000378:metabolism; D013552:Swine / Q000235:genetics / Q000502:physiology*
D011960:Receptors, Estrogen; D004958:Estradiol