Riedel Julia, Schermuly Isabel I, Romanet Stella, Saliu Eva-Maria, Lemme Andreas, Zentek Jürgen, Aschenbach Jörg R
Institute of Veterinary Physiology, Freie Universität Berlin, Berlin, Germany.
Institute of Animal Nutrition, Freie Universität Berlin, Berlin, Germany.
Poult Sci. 2025 Apr 7;104(6):105142. doi: 10.1016/j.psj.2025.105142.
The present study hypothesized that supplementation of different methionine (Met) sources might influence the intestinal absorption of l-Met and 3-O-methyl-d-glucose (3-OMG) in broilers. In a completely randomized study, a total of 53 Cobb500 broilers (30 males and 23 females) received a grower-finisher diet that was either not supplemented with Met (Met + Cys, 0.49 %; control) or supplemented with either 0.27 % l-Met, 0.27 % DL-Met or 0.47 % DL-2‑hydroxy-4-(methylthio) butanoic acid (HMTBA). After ≥10 days on the diets, uptakes of 3-OMG and l-Met were measured in duodenum, mid-jejunum and caecum at 50 µM and 5 mM concentrations in Ussing chambers, each in the presence and absence of Na. We also investigated the mRNA expression of apical glucose and Met transporters. Dietary supplements had no effect on 3-OMG and l-Met uptakes (P > 0.05), except for male broilers receiving DL-Met or DL-HMTBA, that showed higher jejunal uptakes of l-Met than control at 5 mM (P < 0.001). Except for l-Met uptakes at 5 mM, tissue × sodium interactions (P ≤ 0.05) for 3-OMG and l-Met uptakes verified higher uptakes in jejunum compared to duodenum and caecum; with higher uptakes in the presence vs. absence of Na in jejunum only. In duodenum, uptakes of l-Met and 3-OMG at 50 µM concentration were higher in males vs. females. Expression of SGLT1, BAT1, ATB and rBAT, but not ASCT1, were lowest in caecum (P ≤ 0.05). Expression of BAT1 was higher in males vs. females (P ≤ 0.05). Expression of ASCT1 was higher with DL-Met and DL-HMTBA supplements compared to l-Met and control (P ≤ 0.05). These findings indicate that jejunum is the main intestinal segment for Na-dependent l-Met and 3-OMG absorption in broilers with minor effects of dietary Met source. A sexual dimorphism for duodenal nutrient uptake and mRNA abundance of BAT1 was congruent with the more efficient growth performance of male chickens known from the literature.
本研究假设，补充不同的蛋氨酸（Met）来源可能会影响肉鸡对L-蛋氨酸和3-O-甲基-D-葡萄糖（3-OMG）的肠道吸收。在一项完全随机的研究中，总共53只科宝500肉鸡（30只雄性和23只雌性）接受了一种育成-育肥期日粮，该日粮要么不补充蛋氨酸（蛋氨酸+半胱氨酸，0.49%；对照组），要么补充0.27%的L-蛋氨酸、0.27%的DL-蛋氨酸或0.47%的DL-2-羟基-4-（甲硫基）丁酸（HMTBA）。在日粮喂养≥10天后，在Ussing室中，分别在存在和不存在Na的情况下，以50µM和5mM的浓度测量十二指肠、空肠中段和盲肠中3-OMG和L-蛋氨酸的摄取量。我们还研究了顶端葡萄糖和蛋氨酸转运蛋白的mRNA表达。日粮补充剂对3-OMG和L-蛋氨酸的摄取没有影响（P>0.05），但接受DL-蛋氨酸或DL-HMTBA的雄性肉鸡除外，它们在5mM时空肠中L-蛋氨酸的摄取量高于对照组（P<0.001）。除了5mM时L-蛋氨酸的摄取量外，3-OMG和L-蛋氨酸摄取量的组织×钠相互作用（P≤0.05）证实，空肠中的摄取量高于十二指肠和盲肠；仅在空肠中，存在Na时的摄取量高于不存在Na时。在十二指肠中，50µM浓度下雄性肉鸡L-蛋氨酸和3-OMG的摄取量高于雌性。SGLT1、BAT1、ATB和rBAT的表达，但不包括ASCT1，在盲肠中最低（P≤0.05）。BAT1的表达在雄性中高于雌性（P≤0.05）。与L-蛋氨酸和对照组相比，添加DL-蛋氨酸和DL-HMTBA时日粮中ASCT1的表达更高（P≤0.05）。这些发现表明，空肠是肉鸡中依赖Na的L-蛋氨酸和3-OMG吸收的主要肠道段，日粮蛋氨酸来源的影响较小。十二指肠营养物质摄取的性别二态性和BATI的mRNA丰度与文献中已知的雄性鸡更有效的生长性能一致。
