Rodger Johnson and Joe Cassady
Summary and Implications
Four experiments were conducted to determine whether boars and gilts from selected lines that differ in ovulation rate and litter size also differ in plasma concentrations of Follicle Stimulating Hormone (FSH). Plasma FSH was studied because it is a potential indicator trait of ovulation rate. Plasma concentrations of FSH in young boars and gilts differed between the select and the control line. It is likely that this difference is due to a correlated response to selection for ovulation rate. Therefore, plasma concentration of FSH in young boars and gilts may be a trait that can be used effectively to indirectly select for ovulation rate. Additional data to more precisely estimate the genetic relationships are needed before selection for FSH is recommended.