Zhong R Z, Xia J Q, Sun H, Qin G X
College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin, China.
Northeast Institute of Geography and Agroecology, Chinese, Academy of Sciences, Changchun, Jilin, China.
J Anim Physiol Anim Nutr (Berl). 2017 Oct;101(5):e312-e322. doi: 10.1111/jpn.12607. Epub 2017 Jan 6.
To determine the effects of different sources of protein on the growth performance of newly weaned piglets, 72 newly weaned piglets were randomly assigned to three groups fed different diets (soya bean, casein and dried distillers' grain with solubles (DDGS) feeds). Casein and DDGS feeds consisted of soya bean feed in which 5% of the CP was replaced with casein- or DDGS-derived CP respectively. Blood and chyme samples were collected from each piglet 2 h post-feeding on days 0 and 28 of the feeding period. The DDGS feed decreased DMI (p = 0.024) and increased FCR (p = 0.025) due to lower nitrogen utilization (p = 0.078) than those of other feeds. Total amino acid content in chyme demonstrated that casein feed digested rapidly in the duodenum (p = 0.005), whereas DDGS feed was digested primarily in the distal jejunum (p = 0.003) and ileocecum (p = 0.002). However, polypeptide profiles in chyme exhibited a pattern different from those of amino acids. There were no differences in the polypeptide profiles in the stomachs of piglets fed soya bean or casein feeds (p > 0.05), but soya bean group had greater amounts of small polypeptides (mass under m/z 3000 Da) in the duodenum (p = 0.052) than other groups. In contrast, the DDGS feed group had more large polypeptides (m/z 3000-4000 Da) in the stomach than the other groups (p < 0.001). In addition, 10 pairs of polypeptides with matching masses were identified in the plasma and digesta, indicating that polypeptides may have been transported across the intestinal epithelial cells and into the blood. Taken together, substitution of 5% of the CP in soya bean meal-based feed with DDGS-derived CP decreased the growth performance of newly weaned piglets due to poor digestibility and N utilization of DDGS feed, as well as untimely digestion of casein feed.
为了确定不同蛋白质来源对刚断奶仔猪生长性能的影响，72头刚断奶仔猪被随机分为三组，分别饲喂不同日粮（大豆、酪蛋白和玉米干酒糟及其可溶物（DDGS）日粮）。酪蛋白和DDGS日粮由大豆日粮组成，其中分别用酪蛋白或DDGS来源的粗蛋白替代了5%的粗蛋白。在饲喂期的第0天和第28天，在每头仔猪采食后2小时采集血液和食糜样本。与其他日粮相比，DDGS日粮由于氮利用率较低（p = 0.078），降低了干物质采食量（DMI，p = 0.024）并提高了料重比（FCR，p = 0.025）。食糜中的总氨基酸含量表明，酪蛋白日粮在十二指肠中消化迅速（p = 0.005），而DDGS日粮主要在空肠远端（p = 0.003）和回盲部（p = 0.002）消化。然而，食糜中的多肽谱呈现出与氨基酸不同的模式。饲喂大豆或酪蛋白日粮的仔猪胃中的多肽谱没有差异（p > 0.05），但大豆组十二指肠中的小肽（质量小于3000 Da）含量比其他组更高（p = 0.052）。相反，DDGS日粮组胃中的大肽（m/z 3000 - 4000 Da）比其他组更多（p < 0.001）。此外，在血浆和消化物中鉴定出10对质量匹配的多肽，表明多肽可能已通过肠上皮细胞转运到血液中。综上所述，用DDGS来源的粗蛋白替代基于豆粕的日粮中5%的粗蛋白会降低刚断奶仔猪的生长性能，这是由于DDGS日粮消化率和氮利用率差以及酪蛋白日粮消化不及时所致。
