Improving the synchrony between amino acids (AAs) and glucose appearance in the blood can support the growth performance of weaned pigs fed low crude protein (CP) diet. This can be achieved by using a diet with a low amylose to amylopectin ratio (AM/AP). The aim of this experiment was to evaluate whether reducing the AM/AP by using a corn variety characterized by a high amylopectin content, in the weaning diet can sustain growth performance and improve the intestinal health of pigs fed a low CP diet. At weaning (25±2 days), 90 pig were assigned to three treatment group: 1) control group (CTR), fed a standard diet with a medium-high CP content and high AM/AP (d 0 to 13: 18.0% CP, 0.13 AM/AP; d 14 to 27: 16.6% CP, 0.30 AM/AP; d 28 to 49: 16.7% CP, 0.15 AM/AP); 2) a group fed a low CP diet with a high AM/AP (LP), (d 0 to 13: 16.0% CP, 0.17 AM/AP; d 13 to 27: 14.7% CP, 0.17 AM/AP; d 28 to 49: 14.5%CP, 0.25 AM/AP); 3) a group fed a low CP and a low AM/AP diet (LPLA) (d 0 to 13: 16.0% CP, 0.09 AM/AP; d 14 to 27: 14.7% CP, 0.05 AM/AP; d 28 to 49: 14.5%CP, 0.09 AM/AP). Pigs were weighted weakly until d49. Fecal samples were collected at d 10 a d 42 (12 samples/group/timepoint) for ammonia and calprotectin content and microbiota profile characterization. Until d28, body weight (BW) of pigs from CTR was not different from pigs of the LPLA group, whereas it was higher from pigs of the LP group (P <0.05). Thereafter, CTR group had greater BW compared with LP and LPLA groups for all the other timepoints considered (P < 0.05). From d 0-7 LPLA group had a lower incidence of diarrhea than the LP group (P = 0.04). At d 10, LPLA group had a greater alpha diversity (Shannon and InvSimpson indices), than the CTR (P = 0.03) and LP (P = 0.04) groups. At d 42, LPLA group had significantly greater InvSimpson diversity than LP group (P = 0.028). At d 10, LP group was characterized by greater abundance of Lactobacillus (LDA score = 5.15, P = 0.02), Clostridium-sensu-stricto-1 (LDA score = 4.90, P = 0.02) and Oscillospiraceae NK4A214-group (LDA score = 4.87, P = 0.004), whereas LPLA group was characterized by greater abundance of Prevotella (LDA score = 5.04, P = 0.003) and Agathobacter (LDA score= 4.77, P = 0.05). In conclusion, while reducing CP levels may negatively impact growth performance, when combined with higher amylopectin levels, it can reduce the incidence of diarrhea and increase fecal microbial diversity.

中文翻译：

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降低低蛋白日粮中直链淀粉-支链淀粉比率：对断奶仔猪生长性能和肠道健康的影响


改善氨基酸 （AAs） 和血液中葡萄糖外观之间的同步性可以支持饲喂低粗蛋白 （CP） 日粮的断奶仔猪的生长性能。这可以通过使用低直链淀粉与支链淀粉比率 （AM/AP） 的饮食来实现。本实验的目的是评估在断奶日粮中使用以支链淀粉含量高为特征的玉米品种来降低 AM/AP 是否可以维持生长性能并改善饲喂低 CP 日粮的猪的肠道健康。断奶时（25±2 天），将 90 头猪分为三个处理组：1） 对照组 （CTR），饲喂中高 CP 含量和高 AM/AP 的标准日粮（第 0 至 13 天：18.0% CP，0.13 AM/AP;第 14 至 27 天：16.6% CP，0.30 AM/AP;第 28 至 49 天：16.7% CP，0.15 AM/AP）;2） 一组喂食低 CP 饮食和高 AM/AP （LP），（d 0 至 13：16.0% CP，0.17 AM/AP;D 13 至 27：14.7% CP，0.17 AM/AP;D 28 至 49：14.5%CP，0.25 AM/AP）;3） 一组喂食低 CP 和低 AM/AP 饮食 （LPLA）（d 0 至 13：16.0% CP，0.09 AM/AP;d 14 至 27：14.7% CP，0.05 AM/AP;d 28 至 49：14.5%CP，0.09 AM/AP）。猪体重较弱，直到 d49。在第 10 天和第 42 天（12 个样品/组/时间点）收集粪便样品，用于氨和钙卫蛋白含量和微生物群谱表征。截至 d28，CTR 猪的体重 （BW） 与 LPLA 组猪没有差异，而 LP 组猪的体重 （BW） 更高 （P <0.05）。此后，在所有其他考虑的时间点，与 LP 和 LPLA 组相比，CTR 组具有更大的 BW （P < 0.05）。从 d 0-7 开始，LPLA 组腹泻发生率低于 LP 组 （P = 0.04）。第 10 天时，LPLA 组的 α 多样性 （Shannon 和 InvSimpson 指数） 高于 CTR （P = 0.03） 和 LP （P = 0.04） 组。 在 d 42 时，LPLA 组的 InvSimpson 多样性显著高于 LP 组 （P = 0.028）。第 10 天时，LP 组的特征是乳酸菌 （LDA 评分 = 5.15，P = 0.02） 、严格梭菌 （LDA 评分 = 4.90，P = 0.02） 和示螺旋菌科 NK4A214 组 （LDA 评分 = 4.87，P = 0.004） 的丰度较高，而 LPLA 组的特征是普雷沃菌属 （LDA 评分 = 5.04，P = 0.003） 和阿加索杆菌 （LDA 评分 = 4.77，P = 0.05） 的丰度更高。总之，虽然降低 CP 水平可能会对生长性能产生负面影响，但当与较高的支链淀粉水平相结合时，它可以降低腹泻的发生率并增加粪便微生物多样性。