Morsy Tarek A, Kholif Ahmed E, Adegbeye Moyòsore J, Olafadehan Olurotimi A, Gouda Gouda A, Fahmy Mahmoud, Chahine Mireille
Dairy Science Department, National Research Centre, 33 Bohouth St. Dokki, Giza 12622, Egypt.
Department of Animal Sciences, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA.
Animals (Basel). 2024 Jul 20;14(14):2119. doi: 10.3390/ani14142119.
The inevitable enteric gas emission from ruminants is considered a modern-day problem from an environmental perspective. Addressing this problem requires nutritional approaches such as the use of phytogenic additives in ruminant diets. In this regard, lupin seed (LS) can be a useful additive due to its phytochemical constituents. Therefore, this study investigated the effects of lupin () seed supplementation as a functional and sustainable feed additive in sheep diet (50:50 concentrate-to-forage ratio) on gas production (GP; mL/g DM), methane (CH; mL/g DM) and carbon dioxide (CO; mL/g DM) emissions, fermentation parameters, and nutrient degradability (g/kg DM incubated). Gas production and CH were measured per gram of incubated dry matter (DM), degradable DM (DM), degradable neutral detergent fiber (NDF), and degradable acid detergent fiber (ADF). Lupin seeds were included at 0 (control), 0.5, 1.0, 1.5, and 2% of the diet. The seeds contained 3.27% essential oils (DM basis), with eucalyptol as the main phytochemical. The highest GP per gram of DM and DM was observed ( < 0.01) with 2.0% LS supplementation level. While 1.0% LS had the highest GP per gram of NDF, 0.5% lupin diet had the highest GP per gram of ADF. Asymptotic GP and CH emissions linearly and quadratically increased ( < 0.01) with increasing LS level, while lag time decreased. Despite increased CH production, the proportion of CH in total biogas was lower ( = 0.008) for LS treatments than the control, with the 0.5% LS showing the lowest CH proportion. Production of CO increased with lupin seed treatments, with 0.5% LS producing the highest proportion ( = 0.027). Degradability of DM, NDF, and ADF was greater ( < 0.01) for the high LS supplementation level, while 0.5% supplementation level decreased ADF degradability. Total short-chain fatty acids, acetic acid, and propionic acid increased ( < 0.05) with LS supplementation level, leading to a reduced acetate:propionate ratio. Rumen pH decreased ( = 0.036) with LS supplementation, while ammonia-N decreased ( = 0.045) and estimated metabolizable energy increased ( < 0.001) linearly. Calculated microbial protein synthesis ( = 0.005) and gas yield ( = 0.047) increased with LS supplementation level. LS supplementation at 2.0% of diet (DM basis) increased GP and CH emission (mL/g DM) and enhanced nutrient degradability, suggesting its potential use as a functional feed additive for ruminants when supplemented at a 2.0% level into diet.
从环境角度来看，反刍动物不可避免的肠道气体排放被视为一个现代问题。解决这个问题需要采用营养方法，比如在反刍动物日粮中使用植物源添加剂。在这方面，羽扇豆种子（LS）因其植物化学成分可成为一种有用的添加剂。因此，本研究调查了在绵羊日粮（精料与草料比例为50:50）中添加羽扇豆种子作为功能性和可持续性饲料添加剂对气体产生量（GP；mL/g干物质）、甲烷（CH；mL/g干物质）和二氧化碳（CO；mL/g干物质）排放、发酵参数以及养分降解率（g/kg干物质 incubated）的影响。每克孵化干物质（DM）、可降解干物质（DM）、可降解中性洗涤纤维（NDF）和可降解酸性洗涤纤维（ADF）的气体产生量和CH均被测定。羽扇豆种子在日粮中的添加比例为0（对照）、0.5%、1.0%、1.5%和2%。这些种子含有3.27%的精油（以干物质计），桉叶油是主要的植物化学成分。在添加2.0% LS的水平下，每克DM和DM观察到最高的GP（<0.01）。虽然1.0% LS的每克NDF的GP最高，但0.5%羽扇豆日粮的每克ADF的GP最高。随着LS水平的增加，渐近GP和CH排放呈线性和二次增加（<0.01），而滞后时间减少。尽管CH产量增加，但与对照相比，LS处理组CH在总沼气中的比例更低（=0.008），0.5% LS的CH比例最低。随着羽扇豆种子处理，CO的产量增加，0.5% LS产生的比例最高（=0.027）。高LS添加水平下，DM、NDF和ADF的降解率更高（<0.01），而0.5%添加水平降低了ADF降解率。随着LS添加水平的增加，总短链脂肪酸、乙酸和丙酸增加（<0.05），导致乙酸:丙酸比例降低。随着LS添加，瘤胃pH降低（=0.036），而氨氮降低（=0.045），估计的代谢能呈线性增加（<0.001）。计算得出的微生物蛋白质合成（=0.005）和气体产量（=0.047）随着LS添加水平的增加而增加。日粮中添加2.0%（以干物质计）的LS增加了GP和CH排放（mL/g干物质），并提高了养分降解率，表明当以2.0%的水平添加到日粮中时，其有潜力作为反刍动物的功能性饲料添加剂。
