Influence of Breed of Sire, Dietary Intake and Housing Facilities on the Attainment of Puberty in Crossbred Gilts

Abstract

Dycx, G. W. 1989. lnfluence of breed of sire, dietary intake and housing facilities on the attainment of puberty in crossbred gilts. Can. J. Anim. Diet intake restriction and group penning had similar effects on the mean interval to puberty, with C and R gilts averaging 13.6+1.0 and 11 .4+1.0 d (P<0.01), and S and G gilts averaging 12.3+0.9 and 18.7-F 1.1 d (P<0.01). Both the R and G treatments resulted in a delay in the attainment of puberty as compared to S-penned C gilts. This difference was apparent within 3 d. The delay in puberty associated with diet intake restriction was found only in S-penned gilts and was eliminated l0 d after the R gilts were placed on the C level of diet intake. The group penning delay in attaining puberty was evident for 31 d in Y-sired gilts and to the end of the experiment in L-sired gilts.In L-sired gilts 85.3 and 55.6% of the S and G gilts, respectively, attained puberty (P<0.05) as compared to74.6 and76.9% of the Y-sired gilts. Thus, the ability of the gilt to attain pubeny in response to boar exposure is dependent on the breed of gilt, diet intake and pen type, with stails and an adequate growth rate required for the greatest response.

The effect of postulating diet intake on embryonic and fetal survival, and litter size in gilts

“…Each year during the second week of October and indeoendent of their age at pubefty, 80-100 of the gilts were assigned to the present experiment. Weight at 160 d of age and the probed backfat depth (adjusted to 90 kg wt) did not influence age at puberty (Dyck 1989 (Dyck 1989). …”

“…In alternate years the gilts were mated by artificial insemination (AI) with Landrace (L) and Yorkshire (Y) (Dyck 1989). Each year during the second week of October and indeoendent of their age at pubefty, 80-100 of the gilts were assigned to the present experiment.…”

The effect of level of diet intake after mating on the serum concentration of thyroxine, triiodothyronine, growth hormone, insulin and glucose, and embryonic survival in the gilt

“…Fetal thyroid function is required for normal fetal growth (Colenbrander et al 1984), and INS stimulates placental lactogen production and inhibits estradiol secretion (Hochberg et al 1983 Progesterone was measured to determine whether the effects of the metabolic hormones were associated with the concentration of Po. The gilts were part of a larger population, and their management prior to the experiment was previously described (Dyck 1989(Dyck , 1991. The gilts were placed on the experiment (Dyck 1989) When the analysis of the four profiles approached significance (P < 0.15), the same procedure was used to compare all profiles with each other to determine which differences were significant.…”

“…The gilts were part of a larger population, and their management prior to the experiment was previously described (Dyck 1989(Dyck , 1991. The gilts were placed on the experiment (Dyck 1989) When the analysis of the four profiles approached significance (P < 0.15), the same procedure was used to compare all profiles with each other to determine which differences were significant.…”