223 Impact of Bump Feeding in Late Gestation on Reproductive Performance and Body Weight and Body Condition at Pre- and Post-Farrowing and at Weaning in Hyper Prolific Gilts

Abstract The study aimed to quantify the effect of increasing the feeding level during late gestation on reproductive performance, body weight (BW) and body condition (BC) at pre- and post-farrowing and at weaning in gilts. A total of 815 PIC Camborough X54 gilts were individually weighed at day 90 of gestation and assigned to two feeding levels in a randomized complete block design. Gilts received either 2.3 kg/d [4.95 Mcal/d of net energy (NE) and 11.5 g/d of standard ileal digestible lysine (SID Lys); CONTROL] or 3.1 kg/d (6.67 Mcal/d of NE and 15.5 g/d of SID Lys; BUMP) from 90 d until farrowing. Gilts were housed in group pens during gestation and feed was provided using a feed box setting. Feed contained 2.15 Mcal/kg of NE and 5 g/kg of SID Lys. Caliper information was individually collected at day 90 of gestation to assess BC. Caliper and BW measurements were collected pre-farrowing and at weaning and their difference was calculated. Additionally, post-farrowing 48 h BW was predicted using the following equation: Gilt 48h post-farrow BW = -20.81 + (0.98 × pre-farrow BW). Total born (TB), born alive (BA), stillborn (SB), and mummified (MM) were collected for each gilt at farrowing, and their percentage per litter was calculated and used for analysis. Data were analyzed using a general linear model considering gilt as the experimental unit. The model included treatment as fixed effect and gilt as random effect. Caliper or BW at 90 days of gestation were considered as covariable for BW and BC analysis, respectively. Alpha for determination of significance was 0.05 and trend were identified at 0.10. BUMP gilts were 7.5 and 7.4 kg heavier than CONTROL gilts at pre- and post-farrowing, respectively (P < 0.001; Table 1). The BW at weaning did not differ between treatments (P = 0.32); however, BUMP gilts lost 6.3 kg BW more than CONTROL gilts (P < 0.001; Table 1) during the lactation period. Regarding BC, caliper at pre-farrow was 0.3 units greater for BUMP gilts compared with CONTROL gilts (P < 0.001; Table 1). No differences were observed in caliper loss during the lactation period and at weaning between treatments (P > 0.05; Table 1). The BUMP gilts tended to have 0.5 more TB compared with CONTROL gilts (P = 0.054; Table 1). Nevertheless, TB is related to the early gestation period and embryo survivability. No differences were observed in BA, SB and MM between treatments (P > 0.05; Table 1). In summary, increasing the feeding level by 0.9 kg/d in late ge