The effect of confinement on days to puberty in gilts.

In the late fall and winter of 1982 to 1983, 112 crossbred gilts were used in a factorially arranged experiment to determine the effect of confinement on the age at which a gilt reaches first estrus (puberty). Two environments (confinement and nonconfinement) and three ages at movement to non-confinement ( 100, 140, and 180 d) were studied. No differences were detected (P> .05) between confinement and non-confinement in the proportions of gilts reaching puberty by 210 d of age. Gilts were older at puberty (P .05) between age-of-movement groups. However, a higher (P<.05) proportion of the non-confinement gilts reached puberty within 10 d after the beginning of boar exposure than confinement (44.6 vs 26.8%). Moving gilts from confinement to non-confinement (pasture) at 180 d appeared to be the most effective method tested for inducing puberty in gilts. (