Nampoothiri Vinu M, Mohini Madhu, Malla Bilal A, Mondal Goutam, Pandita Sujata
Division of Animal Nutrition, ICAR-National Dairy Research Institute, Karnal, Haryana 132001, India.
Division of Animal Physiology, ICAR-National Dairy Research Institute, Karnal, Haryana 132001, India.
Anim Nutr. 2018 Jun;4(2):215-221. doi: 10.1016/j.aninu.2018.01.009. Epub 2018 Feb 17.
The present study investigated the effects of different dietary forage to concentrate ratios on animal performance, and enteric and manure greenhouse gas emissions in growing calves. Fifteen male Murrah calves (153.5 ± 18.17 kg; 6 to 12 months) were randomly assigned to 3 dietary treatments and fed corn fodder, wheat straw and concentrate in 3 different proportions: 20:60:20 (C20); 20:40:40 (C40) and 10:30:60 (C60), for a period of 120 days. Increasing dietary concentrate proportion had no significant ( > 0.05) effect on dry matter intake (DMI) but increased crude protein (CP) and total digestible nutrient intake ( < 0.05). Average daily gain and feed conversion efficiency were significantly higher ( < 0.05) for C60 compared with C20 and for C40, these did not differ with C20 and C60 ( > 0.05). The apparent digestibility of dry matter, organic matter and CP were higher ( < 0.05), but acid detergent fiber digestibility was lower ( < 0.05) for C60 compared with C20 whereas, ether extract and neutral detergent fiber digestibilities were not affected ( > 0.05). Daily methane (CH) emission (g/d), CH energy loss (MJ/d) and CH yield (CH g/kg organic matter intake [OMI], CH g/kg digestible OMI, and CH % of metabolizable energy intake) were significantly higher for C20 compared with C60 ( < 0.05). Methane yield as g/kg DMI although lower for C60 compared with C20 but the difference was not significant ( > 0.05). Manure CH (g/kg DMI) and nitrous oxide (NO mg/kg nitrogen) emissions were not affected ( > 0.05), but NO emission on mg/kg DM basis was significantly higher ( < 0.05) from the manure of calves fed C60 than that for C20. Thus, increasing dietary concentrate proportion improved animal performance, and reduced enteric CH emission (g/day) without any significant effect on manure NO (mg/kg nitrogen) and CH emissions.
本研究调查了不同日粮粗饲料与精饲料比例对生长犊牛的生产性能、肠道及粪便温室气体排放的影响。15头雄性摩拉水牛犊牛（体重153.5 ± 18.17千克；6至12月龄）被随机分配到3种日粮处理组，分别饲喂玉米秸秆、小麦秸秆和精饲料，比例分别为20:60:20（C20）、20:40:40（C40）和10:30:60（C60），为期120天。日粮精饲料比例增加对干物质采食量（DMI）无显著影响（P>0.05），但粗蛋白（CP）和总可消化养分采食量增加（P<0.05）。与C20相比，C60的平均日增重和饲料转化率显著更高（P<0.05），C40与C20和C60相比无差异（P>0.05）。与C20相比，C60的干物质、有机物和CP的表观消化率更高（P<0.05），但酸性洗涤纤维消化率更低（P<0.05），而乙醚提取物和中性洗涤纤维消化率不受影响（P>0.05）。与C60相比，C20的每日甲烷（CH）排放量（克/天）、CH能量损失（兆焦/天）和CH产量（CH克/千克有机物摄入量[OMI]、CH克/千克可消化OMI以及CH占代谢能摄入量的百分比）显著更高（P<0.05）。C60的CH产量（克/千克DMI）虽低于C20，但差异不显著（P>0.05）。粪便CH排放量（克/千克DMI）和氧化亚氮（NO毫克/千克氮）排放量不受影响（P>0.05），但以毫克/千克干物质计，饲喂C60的犊牛粪便中NO排放量显著高于C20（P<0.05）。因此，增加日粮精饲料比例可提高犊牛生产性能，并减少肠道CH排放量（克/天），而对粪便NO（毫克/千克氮）和CH排放量无显著影响。
