Ipema Allyson F, Gerrits Walter J J, Bokkers Eddie A M, van Marwijk Manon A, Laurenssen Bjorge F A, Kemp Bas, Bolhuis J Elizabeth
Adaptation Physiology Group, Department of Animal Sciences, Wageningen University and Research, Wageningen, Netherlands.
Animal Nutrition Group, Department of Animal Sciences, Wageningen University and Research, Wageningen, Netherlands.
Front Vet Sci. 2022 Feb 16;9:838018. doi: 10.3389/fvets.2022.838018. eCollection 2022.
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, = 14 litters) or creep feed and live BSFL (Pre-L, = 15 litters) , and post-weaning piglets either had no access to live BSFL (Post-C, = 24 pens) or they could rotate tubes that released BSFL (Post-L, = 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, = 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.
断奶对仔猪来说是一个压力较大的事件，这会使其营养和社会环境发生重大变化。在断奶前后提供可食用的富集物，可能会通过增加断奶前采食量、改善断奶后性能、健康状况、行为和情感状态来缓解断奶过渡。在本研究中，我们调查了在断奶前和/或断奶后提供活体黑水虻幼虫（BSFL）作为可食用富集物的效果。断奶前，仔猪要么只接受开食料（Pre-C，n = 14窝），要么接受开食料和活体BSFL（Pre-L，n = 15窝）；断奶后，仔猪要么无法接触活体BSFL（Post-C，n = 24栏），要么可以转动管子释放BSFL（Post-L，n = 24栏），释放量最高可达其预期每日干物质摄入量的20%，从而形成CC、CL、LC和LL四种处理方式。对于任何测量参数，均未发现断奶前和断奶后处理之间存在交互作用。断奶前，Pre-L组仔猪与幼虫互动的偏好高于开食料，Pre-C组仔猪与开食料的互动多于Pre-L组仔猪。用于采食行为的总时间没有差异。持续提供幼虫增加了盲肠长度和近端胃消化物pH值，同时在断奶后第3天降低了葡萄糖和异硫氰酸荧光素通过结肠壁的通过率（CC组与LL组相比，n = 12头仔猪/处理组）。断奶后腹泻和最终体重不受处理方式的影响。断奶后，Pre-C组仔猪的采食量往往更多，生长速度略快于Pre-L组仔猪。Post-C组仔猪采食时间更长，断奶后的采食量高于Post-L组仔猪。根据圈舍内行为观察，Post-L组仔猪积极探索并食用幼虫。与Post-L组仔猪相比，Post-C组仔猪在第8天花费更多时间探索环境和拱碰同栏伙伴，并且在第8天和第15天更多地与同栏伙伴互动玩耍。断奶后第4天和第5天，仔猪对新环境的反应和注意力偏向测试不受幼虫供应的影响。总之，断奶前提供幼虫并没有提高断奶前采食量和断奶后性能，然而断奶后提供幼虫确实有利于仔猪行为，因为观察到其对同栏伙伴的攻击性较小。
