1Instituto de Ganadería de Montaña,CSIC-Universidad de León,Finca Marzanas s/n,24346 Grulleros,León,Spain.
2Estación Experimental del Zaidín,CSIC,Profesor Albareda,1,18008 Granada,Spain.
Animal. 2018 Oct;12(10):2115-2122. doi: 10.1017/S1751731118000836. Epub 2018 Apr 22.
Bacteria firmly attached to the gastrointestinal epithelium during the pre-weaning phase may show a significant impact on nutrient processing, immunity parameters, health and feed efficiency of lambs during post-weaning phases. Thus, the aim of this study was to describe the differences in the ileal epimural microbiota (e.g. total bacteria, Prevotella spp., Bifidobacterium spp. and Lactobacillus spp.) of fattening lambs promoted by early feed restriction during the suckling phase trying to elucidate some of the underlying mechanisms behind changes in feed efficiency during the fattening period. A total of 24 Merino lambs (average BW 4.81±0.256 kg) were used, 12 of them (ad libitum, ADL) kept permanently in individual pens with their mothers, whereas the other 12 lambs were separated from their dams for 9 h each day to be exposed to milk restriction (RES). After weaning (BW=15 kg) all the animals were penned individually, offered the same complete pelleted diet (35 g/kg BW per day) and slaughtered at a BW of 27 kg. During the fattening period, reduced gain : feed ratio (0.320 v. 0.261, P<0.001) was observed for the RES group. Moreover, increments of Prevotella spp. were detected in the ileal epimural microbiota of RES lambs (P<0.05). There were also higher numbers of infiltrated lymphocytes (T and B cells) in the ileal lamina propria (P<0.05), a higher M-cell labelling intensity in ileal Peyer's patches domes (P<0.05) and a trend towards a thickening of the submucosa layer when compared with the ADL group (P=0.057). Some other immunological parameters, such as an increased immunoglobulin A (IgA) production (pg IgA/µg total protein) and increments in CD45+ cells were also observed in the ileum of RES group (P<0.05), whereas transforming growth factor β and toll-like receptor gene expression was reduced (P<0.05). In conclusion, early feed restriction during the suckling phase promoted changes in ileal epimural microbiota and several immunity parameters that could be related to differences in feed efficiency traits during the fattening period of Merino lambs.
在断奶前阶段，牢固附着在胃肠道上皮的细菌可能会对断奶后羔羊的营养处理、免疫参数、健康和饲料效率产生重大影响。因此，本研究的目的是描述早期哺乳阶段限制饲料喂养对育肥羔羊回肠上皮微生物区系（如总细菌、普雷沃氏菌属、双歧杆菌属和乳酸杆菌属）的影响，试图阐明育肥期间饲料效率变化背后的一些潜在机制。共使用了 24 只美利奴羔羊（平均 BW 4.81±0.256kg），其中 12 只（自由采食，ADL）永久性地饲养在单独的与母羊在一起的围栏中，而其余 12 只羔羊每天与母羊分离 9 小时，以暴露于牛奶限制（RES）。断奶后（BW=15kg），所有动物都单独饲养，提供相同的完整颗粒饲料（35g/kg BW 每天），并在 BW 为 27kg 时屠宰。在育肥期间，RES 组的增重：饲料比（0.320 比 0.261，P<0.001）降低。此外，在 RES 羔羊的回肠上皮微生物区系中检测到普雷沃氏菌属的增加（P<0.05）。回肠固有层中的浸润淋巴细胞（T 和 B 细胞）数量也更高（P<0.05），回肠派尔集合淋巴结穹隆中的 M 细胞标记强度更高（P<0.05），与 ADL 组相比，黏膜下层厚度有增厚趋势（P=0.057）。在 RES 组的回肠中还观察到其他一些免疫参数的增加，如免疫球蛋白 A（IgA）产量增加（pg IgA/µg 总蛋白）和 CD45+细胞增加（P<0.05），而转化生长因子 β和 Toll 样受体基因表达减少（P<0.05）。总之，早期哺乳阶段限制饲料喂养促进了回肠上皮微生物区系和几种免疫参数的变化，这些变化可能与美利奴羔羊育肥期饲料效率性状的差异有关。
