Neither photoperiod in the farrowing room nor time of weaning affect nursery performance
Weaning may result in anorexia and reduced growth in pigs especially during the initial 24 to 48 h in the nursery. This study was designed to determine if altering the photoperiod in the farrowing room and/or if weaning at the end of the light or dark cycle would affect performance post-weaning. Twelve farrowing rooms, 13 sows/room, were assigned to one of four treatments approximately one wk prior to farrowing. Treatments, arranged as a 2 x 2 factorial included 2 farrowing room photoperiods; 16 h light:8 h dark (16L:8D) or 8L:16D, and 2 weaning times; end of the dark or end of the light cycle. Pigs were weaned at 25 (± 1) d of age into nurseries maintained on a 16L:8D regime at time 0 of the dark cycle. Pigs were fed standard commercial diets, in a 2 phase feeding program in the nursery. The phase 1 nursery diet was spiked with ferric oxide pellets for 24 h post-weaning and anal swabs taken at 48 h post-weaning allowed pigs to be designated as “eaters” or “non-eaters”. Neither farrowing room photoperiod nor weaning time affected ADG (P > 0.10) in the farrowing room (236 g/d; birth to weaning) or nursery (437 g/d, weaning to 54 d of age). On d 0 to 7 post-weaning, there was a tendency for a photoperiod by weaning time interaction for ADFI (P = 0.06). The lowest intakes (123 g/d) were observed for pigs who had been on the 16L:8D lighting regime and weaned at the end of the dark cycle. ADFI was similar among the other treatments and averaged 157 g/d. Neither photoperiod nor time of weaning affected the percentage of pigs (34 %) identified as “eaters” during the initial 24 h in the nursery (P > 0.10). Pigs identified as “eaters” were lighter at weaning (7.26 vs 7.62 kg BW; P < 0.01), but showed improved ADG from d 0 to 7 post-weaning relative to “non-eaters” (187 vs 141 g/d; P < 0.01). Nursery exit weights were similar between “eaters” (19.6 kg) and “non-eaters” (21.0 kg; P> 0.10). Farrowing room photoperiod and/or weaning at the end of the dark or light cycle did not affect nursery performance. Pigs exhibiting evidence of phase 1 feed consumption immediately post-weaning were lighter; however they had higher ADG immediately post-weaning than those identified as non-eaters.
swine, weaning, photoperiod