The effect of energy intake on age at puberty in gilts.

Abstract

From 12 to 38 weeks old 680 Dutch Landrace gilts were given diets to provide 3.0 M, 2.5 M, 2.1 M and 1.8 M (where M = metabolizable energy required for maintenance). At the 2 greater energy intakes 9.3 and 7.7% of gilts had to be culled, compared with 2.4 and 4.7% for the 2 lower energy intakes. Number of gilts with a spontaneous oestrus was not affected significantly by different energy intakes. Mean daily gain and backfat thickness at 99 kg and at 187 days old were increased by higher energy intake (P<0.01). Age and weight at first oestrus were 234, 237, 237 and 244 days and 139, 131, 118 and 109 kg, respectively. At the 2 greater energy intakes, age at spontaneous first oestrus was negatively related to backfat thickness (P<0.05). (Abstract retrieved from CAB Abstracts by CABI’s permission)