The influence of nutritional and management factors on piglet weight gain to weaning in a commercial herd in Denmark

Assessing the Effectiveness of Providing Live Black Soldier Fly Larvae (Hermetia illucens) to Ease the Weaning Transition of Piglets

Weaning is a stressful event for piglets, involving substantial changes to their nutritional and social environment. Providing edible enrichment around weaning may ease the weaning transition by increasing pre-weaning feed intake and improving post-weaning performance, health, behavior, and affective state. In this study, we investigated the effects of providing live black soldier fly larvae (BSFL) as edible enrichment pre- and/or post-weaning. Pre-weaning, piglets received either only creep feed (Pre-C, n = 14 litters) or creep feed and live BSFL (Pre-L, n = 15 litters) ad libitum, and post-weaning piglets either had no access to live BSFL (Post-C, n = 24 pens) or they could rotate tubes that released BSFL (Post-L, n = 24 pens) at levels up to 20% of their expected daily dry matter intake, resulting in treatments CC, CL, LC, and LL. No interaction between pre- and post-weaning treatment was found for any of the measured parameters. Before weaning, Pre-L piglets preferred to interact with larvae over creep feed, and Pre-C piglets interacted more with creep feed than Pre-L piglets. Total time spent on feed-directed behaviors did not differ. Continuous larvae provisioning increased caecum length and proximal stomach digesta pH, while it decreased the passage of glucose and fluorescein isothiocyanate through the colon wall on d3 post-weaning (CC vs. LL, n = 12 piglets/treatment). Post-weaning diarrhea and final body weight were not affected by treatment. After weaning, Pre-C piglets tended to eat more and grew marginally faster than Pre-L piglets. Post-C piglets spent more time eating and had a higher feed intake post-weaning than Post-L piglets. Based on home-pen behavioral observations, Post-L piglets actively explored and ate the larvae. Post-C piglets spent more time on exploring the environment and nosing pen mates, and they spent more time on manipulating pen mates on d8 and played more on d8 & 15 compared to Post-L piglets. Piglet responses to a novel environment and an attention bias test on d4 & 5 post-weaning were not influenced by larvae provisioning. In conclusion, pre-weaning larvae provisioning did not improve pre-weaning feed intake and post-weaning performance, however post-weaning larvae provisioning did benefit piglet behavior as less manipulation of pen mates was observed.

Interactions between piglet weaning age and dietary creep feed composition on lifetime growth performance

The influences of creep feed composition and piglet weaning age on apparent creep feed disappearance and post-weaning performance were examined. A total of 24 gilts and 72 multiparous sows were selected at farrowing, and their litters allocated to a 2 by 2 factorial arrangement of treatments with the factors being weaning age (22 or 29 days of age) and the composition of the creep feed [simple (diet based predominately on cereals and animal and vegetable protein sources) or complex (diet based predominately on cereals, animal protein sources and 300 g/kg whey powder)]. Creep feed was offered to all litters from 9 days of age to weaning. While creep feed disappearance did not affect pre-weaning growth performance, there was a greater disappearance of the simple creep feed than the complex creep feed from 9 days of age to weaning (776 versus 461 g/litter, respectively, P = 0.004). Apparent creep feed intake from individual piglets in a subset of litters was assessed at three time points (16 and 19 days of age and at weaning), allowing the characterisation of individual pigs as good, moderate, small or non-eaters. There was no difference between treatment groups (χ2 = 6.27, P = 0.71) in the characterisation of apparent creep feed disappearance by individual piglets, however piglets offered the simple creep diet before weaning consumed more feed (P = 0.004) and gained weight faster (P = 0.007) during the first 5 days after weaning than those animals offered the complex creep diet. Feed intake from weaning to 49 days of age also tended to be greater in pigs offered the simple creep diet before weaning (P = 0.053), with this difference reflected in daily gain from weaning to 49 days of age (P = 0.051). Despite these differences, creep feed composition did not influence lifetime growth performance or carcass composition. Pigs weaned at 22 days of age were heavier midway through the weaner period (49 days of age) than pigs weaned at 29 days of age (15.2 versus 14.3 kg, respectively, P = 0.009), and tended to grow faster from birth to slaughter (616 versus 610 g/day, respectively, P = 0.079). These data suggest that the provision of a complex creep diet during lactation may not improve lifetime growth performance above that of a less expensive creep diet. Weaning age may however influence lifetime performance, with weaning at 29 days of age tending to reduce rate of gain from birth to slaughter.

Effects of varying creep feeding duration on the proportion of pigs consuming creep feed and neonatal pig performance

In Exp. 1, 54 sows (PIC Line 1050) and their litters were used to determine the effects of creep feeding duration on the proportion of pigs consuming creep feed and preweaning performance. Two groups of sows were blocked according to parity and date of farrowing and allotted to 3 experimental treatments in a randomized complete block design. Creep feeding was initiated at d 7, 14, and 18 from birth for durations of 13, 6, and 2 d of creep feeding. A creep diet (3,495 kcal of ME/kg, 1.56% standardized ileal digestible Lys) with 1.0% chromium oxide was offered for ad libitum intake until weaning (d 20) in a rotary creep feeder with hopper. Fecal samples from all piglets were taken with sterile swabs on d 14, 18, and 20 for treatment 1, d 18 and 20 for treatment 2, and d 20 for treatment 3. Piglets were categorized as eaters when the fecal sample was colored green at least once on any of the sampling days. In Exp. 1, there were no differences in weaning weights (P > 0.61), total BW gain (P > 0.38), and daily BW gain (P > 0.38) among pigs fed creep for 13, 6, or 2 d. Total creep feed intake of litters fed creep for 13 and 6 d was greater (P < 0.01) than that for litters fed creep feed for 2 d. Litters provided with creep feed for 13 d produced 10% more (80 vs. 70%; P < 0.03) eaters than litters fed creep for 6 or 2 d. In Exp. 2, all 273 pigs weaned from 1 of the 2 groups used in Exp. 1 (averaging 5.67 kg of BW and 20 +/- 2 d) were randomly allotted to 2 treatment categories (non-eater or eater of creep feed) in a completely randomized design to determine whether there were any differences in nursery growth performance between creep feed consumption categories. There were 10 and 33 replications (pens) with 5 to 7 pigs per pen for the non-eater and eater treatment categories, respectively. Non-eaters were heavier (P < 0.004) than eaters at d 0, but eaters had greater ADG (P < 0.01) and ADFI (P < 0.05) than non-eaters from d 0 to 3 postweaning. Overall (d 0 to 28), there were no (P > 0.69) differences in ADG, ADFI, and G:F of eaters and non-eaters. In conclusion, longer durations of creep feeding increased the proportion of eaters in whole litters, but did not affect preweaning performance. Eaters had greater postweaning feed intake than non-eaters, which resulted in greater initial daily BW gains.