This study aimed to investigate the effects of different levels of black soldier fly (BSF) replacing soybean meal (SBM) in diets on the performance and health condition of piglets. A total of 180 weaned piglets were allocated into 5 treatments: BSF0 (corn-soybean meal basal diet), BSF25 (BSF replacing 25% SBM), BSF50 (BSF replacing 50% SBM), BSF75 (BSF replacing 75% SBM) and BSF100 (BSF replacing 100% SBM). During the whole period, in comparison with BSF0, average daily gain (ADG) and average daily feed intake increased in the BSF25 and BSF50 groups, whereas ADG decreased in the BSF75 and BSF100 groups (P < 0.05). The result of quadratic fitting curve showed that piglets exhibited the highest ADG when BSF replaced around 20% SBM. Compared with BSF0, organic matter and dry matter digestibility improved in the BSF25 group, whereas ether extract digestibility decreased in the BSF100 group (P < 0.05). In comparison with BSF0, piglets from the BSF25 group showed a higher duodenal ratio of villus height to crypt depth, increased jejunal sucrase activity, serum neuropeptide Y and ghrelin levels, elevated ileal immunoglobulin (Ig) A, IgG and IgM contents and a lower leptin level, and piglets from the BSF100 group exhibited an increased relative weight of kidney (P < 0.05). However, no significant differences were observed in the expression level of tight junction proteins and chitin-degrading enzyme. Additionally, compared with BSF0, the abundance of short chain fatty acid producing bacteria such as Ruminococcaceae, Faecalibacterium and Butyricicoccus increased, and potential pathogenic bacteria decreased in piglets from the BSF25 group, whereas piglets from the BSF100 group had a greater abundance of harmful bacteria. In conclusion, BSF replacing 25% SBM in diets could improve digestive parameters, immune function and intestinal microbiota, and thus improved growth performance of piglets. However, BSF replacing 100% SBM showed an adverse effect on piglet performance, and the reason might be related to the limited amount of chitin-degrading enzyme.

本研究旨在探讨日粮中不同水平的黑水虻（BSF）替代豆粕（SBM）对仔猪生产性能和健康状况的影响。总共180头断奶仔猪被分配到5个处理：BSF0（玉米豆粕基础日粮）、BSF25（BSF替代25%SBM）、BSF50（BSF替代50%SBM）、BSF75（BSF替代75%SBM）和BSF100 （BSF 取代 100% SBM）。整个时期内，与BSF0组相比，BSF25和BSF50组的平均日增重（ADG）和平均日采食量增加，而BSF75和BSF100组的ADG降低（ P < 0.05 ）  。二次拟合曲线结果表明，当BSF替代20%左右的SBM时，仔猪表现出最高的ADG。与 BSF0 组相比，BSF25 组有机物和干物质消化率提高，而 BSF100 组乙醚浸出物消化率降低（P  < 0.05）。与BSF0相比，BSF25组仔猪的十二指肠绒毛高度与隐窝深度之比较高，空肠蔗糖酶活性、血清神经肽Y和生长素释放肽水平升高，回肠免疫球蛋白（Ig）A、IgG和IgM含量升高，瘦素较低BSF100 组仔猪的肾脏相对重量增加（P  < 0.05）。然而，紧密连接蛋白和几丁质降解酶的表达水平没有观察到显着差异。此外，与BSF0相比， BSF25组仔猪中瘤胃球菌科、粪杆菌属和丁酸球菌等短链脂肪酸产生菌丰度增加，潜在致病菌减少，而BSF100组仔猪有害细菌丰度更高。细菌。总之，日粮中BSF替代25%SBM可以改善消化参数、免疫功能和肠道微生物群，从而改善仔猪的生长性能。然而，BSF替代100%SBM对仔猪生产性能产生不利影响，其原因可能与甲壳素降解酶的用量有限有关。