Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Immunol. 2022 Jul 7;13:908753. doi: 10.3389/fimmu.2022.908753. eCollection 2022.
Huanjiang mini-pig is an indigenous pig breed in China; however, the optimal dietary crude protein (CP) levels for this pig breed during different growth stages has not been standardized yet. This study investigated the effects of different CP levels on diarrhea incidence, immunity, and intestinal barrier function in pigs. A total of 360 Huanjiang mini-pigs were assigned to three independent trials and fed the following CP diets: 5-10 kg stage, 14, 16, 18, 20, and 22%; 10-20 kg stage, 12, 14, 16, 18, and 20% and 20-30 kg stage, 10, 12, 14, 16, and 18%. In the 5-10 kg stage, the 22%; diet increased the plasma IL-1β, IL-6, IL-8, and TNF-α concentrations compared to the 14-20% diets and decreased IL-10 and TGF-β; however, these results were fluctuated in the later stages, including the decrease of IL-1β and IL-8 in the 20% group, TNF-α in the 18-20% groups, and the increase of IFN-γ in the 20% group at the 10-20 kg stage and the decrease of TNF-α in the 16% group at the 20-30 kg stage. The 20% diet increased the jejunal and ileal IL-10 concentration compared to the 14% diet at the 5-10 kg stage, as well as in the 16% diet compared to the 12% diet at the 10-20 kg stage. In addition, ileal IL-10 concentration was increased in the 16% diet compared to the 10, 12, and 18% diets at the 20-30 kg stage. Furthermore, the 18% diet at the 5-10 kg stage and the 16% diet at the 10-20 kg stage decreased jejunal IL-6 expression, whereas the 20% diet increased the TNF-α and IFN-γ at the 5-10 kg stage. The 20% diet increased the Claudin, Occludin, ZO-1, ZO-2, Mucin-1, and Mucin-20 expressions at the 5-10 kg stage, as well as TLR-2, TLR-4, and NF-κB in the 22 and 20% diets at the 5-10 and 10-20 kg stages, respectively. Collectively, these findings suggest optimal dietary CP levels of 16, 14, and 12% for Huanjiang mini-pigs during the 5-10, 10-20, and 20-30 kg growth stages, respectively; and provide the guiding significance of dietary CP levels for Huanjiang mini-pigs during different growth stages.
环江香猪是中国的本土猪种；然而，该猪种在不同生长阶段的最佳日粮粗蛋白（CP）水平尚未标准化。本研究探讨了不同 CP 水平对猪腹泻发病率、免疫力和肠道屏障功能的影响。将 360 头环江香猪分为三个独立试验，并饲喂以下 CP 日粮：5-10kg 阶段，14、16、18、20 和 22%；10-20kg 阶段，12、14、16、18 和 20%；20-30kg 阶段，10、12、14、16 和 18%。在 5-10kg 阶段，22%的日粮与 14-20%的日粮相比，增加了血浆 IL-1β、IL-6、IL-8 和 TNF-α浓度，并降低了 IL-10 和 TGF-β；然而，在后期阶段，这些结果有所波动，包括 20%组中 IL-1β 和 IL-8 的降低、18-20%组中 TNF-α的降低以及 10-20kg 阶段 20%组中 IFN-γ的增加，20-30kg 阶段 16%组中 TNF-α的降低。20%的日粮与 14%的日粮相比，在 5-10kg 阶段增加了空肠和回肠的 IL-10 浓度，与 12%的日粮相比，在 10-20kg 阶段增加了回肠的 IL-10 浓度。此外，在 20-30kg 阶段，16%的日粮与 10、12 和 18%的日粮相比，增加了回肠的 IL-10 浓度。此外，在 5-10kg 阶段，18%的日粮和 10-20kg 阶段的 16%的日粮降低了空肠的 IL-6 表达，而 20%的日粮增加了 5-10kg 阶段的 TNF-α和 IFN-γ。20%的日粮在 5-10kg 阶段增加了 Claudin、Occludin、ZO-1、ZO-2、Mucin-1 和 Mucin-20 的表达，22%和 20%的日粮在 5-10kg 和 10-20kg 阶段增加了 TLR-2、TLR-4 和 NF-κB 的表达。总的来说，这些发现表明，环江香猪在 5-10kg、10-20kg 和 20-30kg 生长阶段的最佳日粮 CP 水平分别为 16%、14%和 12%；并为不同生长阶段的环江香猪提供了日粮 CP 水平的指导意义。
