Boar Libido Affects Pubertal Development of Gilts

University of Nebraska 1997 Swine Day Report. Young boars (10 months) expressing either high (HLB) or low (LLB) libido in standardized mating tests were compared for their ability to stimulate earlier puberty in gilts. Boar exposure was initiated when gilts were either 140 or 160 days old to determine whether the effect of boar libido on attainment of puberty in gilts is influenced by sexual maturation (age) of the gilts. Another group of gilts was isolated from boars (NBE, not boar exposed) and served as controls. Gilts exposed to HLB (10 min/day) reached puberty 8.9 days earlier (P < .06) than gilts exposed to LLB. Gilts exposed to boars, regardless of libido level, reached puberty 21 days earlier (P < .01) than the control gilts. Boar exposure initiated at 140 days induced puberty 11.3 days earlier (P < .06) than when initiated at 160 days. Differences in pubertal responses between HLB and LLB were similar when exposure was initiated at 140 or 160 days. Boar libido is an important component of the boar-stimulating effect on puberty in gilts. Therefore, gilts should be exposed to boars with relatively high libido to achieve optimal pubertal development.