Effects of weight at weaning and plane of feeding on the onset of puberty in gilts

Abstract

Thirty six Large White Yorkshire weanling females of 8 kg (light weaners) and 12 kg (heavy weaners) were randomly maintained on three different planes of feeding with respect to crude protein (CP) and digestible energy (DE) viz. (i) NRC recommended levels as control, (ii) a high plane (HP) of 10 per cent increase of CP and DE with respect to NRC level and (iii) a low plane (LP) of 10 per cent decrease of CP and DE with respect to Nrc from weaning to puberty. The fortnightly and daily weight gain was higher in pigs fed NRC diet. The heavy weaners were having a better growth rate, daily gain, higher feed intake and attained puberty earlier than the light weaners, but the feed conversion efficiency was lower than light weaners. The heavy weaners on high plane attained puberty earlier than animals on NRC or low plane diet. In light weaners, NRC group attained puberty earlier than HP and LP group. In both heavy and light weaners, LP group attained puberty later than the other treatment groups. Plane of feeding has no significant effect on puberty attainment, oestrous cycle length and duration of pubertal cestrus but weight at weaning has a significant effect on the onset of puberty. Oestrous hehaviour expressed as scores was significantly affected by plane of feeding. The animals on high plane diet consumed less feed in both heavy and light weaners and have the highest feed conversion efficiency. The light weaners consumed feed comparatively lower and have better feed conversion efficiency than heavy weaners. The overall result suggested that heavy weaners on high plane diet are most efficient in feed conversion efficiency, economy and attainment of puberty at younger age. On the whole, the heavy weaners are more economical for replacement stock than light weaners.