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61.
用蔗髓、糖蜜和酒精废液等制糖副产品及尿素代替部分精料配制成混合精料,对奶牛进行饲养试验。结果表明:试验组和对照组产奶量分别为7666.60kg和7597.40 kg,差异不显著;试验组比对照组节省精料31%;每1kg 试验精料费0.4473元,比对照组0.5655元减少0.1182元,降低精料成本20.9%;试验组每产1kg 牛奶精料费为0.3697元,比对照组0.4705元减少0.1008元,降低成本21.4%;试验组牛奶乳脂率比对照组高0.19%(0.19个百分点),即提高6%。因此用制糖副产品配制的精料可代替常规精料。  相似文献   
62.
This study evaluated the effects of globin and spray-dried porcine plasma (SDPP) on growth performance, digestibility, nitrogen retention, energy retention efficiency (ERE) and intestinal morphology of broiler chickens. A total of 336-day-old male broiler chickens were reared from 1 to 40 days of age and fed 3 diets (8 replicates/diet, 14 birds/replicate) during 3 feeding phases: starter (1–12 days), grower (12–25 days) and finisher (25–40 days). Isonitrogenous diets were formulated by replacing gluten protein isolate contained in the control diet (C diet) with 2% (starter) or 1% (grower and finisher) spray-dried porcine plasma in the plasma diet (SDPP diet). The globin diet (G diet) was obtained by adding globin on the top of C diet at a dose of 0.08% for the whole rearing period. Total tract apparent digestibility (aD), nitrogen retention and ERE were assessed during the three growing phases. At 12  and 40 days of age, one bird per pen was slaughtered to sample gut, liver, spleen and bursa of Fabricius for histomorphological investigations. The SDPP diet increased body weights of chickens at 12 (+60 g; p < .001), 25 (+101 g; p < .001) and 40 days (+130 g; p = .018) of age compared to C and G diets. Also SDPP improved crude protein aD (+9.7%) and ERE (+12.3%) during the starter phase (p < .001). Dietary globin and SDPP inclusion did not affect either the gut morphology or the histopathological findings in birds at 12 and 40 days of age, despite a numerical (+6.90% and +7.40% respectively) villus height improvement in the SDPP group. Overall, these results confirm that dietary supplementation with SDPP and, to a lesser extent, with globin can improve growth performance and dietary protein and energy utilization in broiler chickens without effect on gut functionality.  相似文献   
63.
The aim of this work was to evaluate systems making organic farms self-sufficient in farm-produced bio-based fuels. The energy balance and environmental load for systems based on rape methyl ester (RME), ethanol and biogas were evaluated using a life cycle perspective. Complete LCAs were not performed. Important constraints when implementing the systems in practice were also identified.  相似文献   
64.
以美国佐治亚洲广为分布的红壤和沙质灰土以及棉花和玉米为试验材料,进行Aspartame生产废液(BST,下同)与传统氮肥尿素、硫酸铵的温室盆栽和恒温土培对比试验。结果表明,BST是很好的氮肥资源,等同于或某种程度上优于尿素和硫酸铵。对土壤的理化性质、氨态氮、硝态氮含量以及对作物吸收Ca,Mg,K等养分和生长发育的影响与常规氮肥相似。但废液中有机态氮的水解以及向硝态氮的转化比尿素要快一些。尿素和BST比硫酸铵更适于在红壤和沙质灰土上施用。  相似文献   
65.
A feeding trial was conducted to evaluate the potential of replacing fish meal with co‐extruded wet tuna viscera and corn meal in diets for juvenile white shrimp Litopenaeus vannamei. Five practical diets were formulated to contain 30% crude protein and 16.6 kJ g?1. The feeding experiment was carried out in a recirculating seawater system with fifteen 25‐L tanks with 15 shrimp per tank. Each dietary treatment was fed in triplicate in a completely randomized design for 41 days. Percent weight gain (WG%), survival (S%) and feed conversion ratio (FCR) were calculated, comparisons of these parameters showed no statistical differences (P>0.05) among treatments. The shrimp almost tripled their weight during the feeding trial. Under the experimental conditions S%, WG% and FCR were either improved or were not significantly influenced by the replacement of fish meal with double co‐extruded viscera+corn, except for a slight increase in feed consumption without affecting FCR. Hence, this product can be included by up to 40% in practical shrimp diets without any detrimental effects.  相似文献   
66.
The control of contaminants in fertilizers and industrial by-products is fundamental to safe food production, and it requires low-cost, reliable test methods. The aim of this study was to evaluate the performance of the USEPA 3051a and alternative analytical methods [concentrated hydrochloric acid (HCl), 10 percent HCl, 10 percent sulfuric acid (H2SO4), and 50 mmol L?1 diethylenetriaminepentaacetic acid (DTPA)] for quantifying the levels of lead, cadmium, chromium, and nickel in zinc and/or copper sources. The sample digestions with concentrated HCl, H2SO4, and nitric acid (HNO3) (USEPA 3051a) were heated. Extraction without heating and stirring was employed in 10 percent HCl and 50 mmol L?1 DTPA methods. The Graybill’s modified F-test, t-test for mean error, and the linear correlation coefficient analysis were used to compare test method performance. Equivalent results to USEPA 3051a were found with the following methods: DTPA for the extraction of lead in zinc sources and concentrated HCl and H2SO4 for the extraction of cadmium and chromium in copper sources. However, the absolute values of cadmium, chromium, and nickel recovered by the use of H2SO4 were greater regardless of the source. The greater extraction of contaminants in the evaluated methods suggests that there is need to review the official method if the aim is to quantify the total levels of these elements in raw materials and mineral fertilizers.  相似文献   
67.
枳实副产物中柠檬苦素最佳提取条件的研究   总被引:5,自引:0,他引:5  
通过单因素试验和旋转正交试验对枳实副产物中柠檬苦素的提取工艺进行优化。结果表明:最佳提取工艺参数为提取剂乙醇浓度78%、pH值6.5、料液比1∶6(w/v)、浸提温度60℃、提取时间2 h,该条件下柠檬苦素的提取率为94.2%。  相似文献   
68.
【目的】随着食品业与加工业的不断发展,产生了诸如西瓜皮,蚕豆荚以及啤酒糟等大量的农副产物,造成环境的污染。为提高农副产物和小麦秸秆的饲料化程度,减小环境压力,通过探究添加剂对农副产物(西瓜皮、蚕豆荚和啤酒糟)与小麦秸秆混合青贮发酵品质的影响,为提高农副产品利用率和青贮品质研究提供借鉴。【方法】以混合农副产物(西瓜皮﹕蚕豆荚﹕啤酒糟=1﹕3﹕4)和小麦秸秆为原材料,按鲜重比100%﹕0(MW)、25%﹕75%(X25)、50%﹕50%(X50)和75%﹕25%(X75)进行混合青贮,并对各混合青贮进行添加剂处理:添加1×106 cfu•g-1布氏乳杆菌(B),0.2% FW纤维素酶(C)和1×106 cfu•g-1鼠李糖乳杆菌(R),以无添加剂(CON)为对照,将不同处理的200g新鲜材料装入容积为250 mL的聚乙烯塑料瓶中。在室温下青贮60 d后,开窖分析发酵品质和营养成分。不同处理的青贮饲料与原料通过两层纱布和定性滤纸过滤,浸提液用于pH测定;将原材料和青贮饲料烘干至恒重后测定干物质含量(DM);蛋白质(CP)采用凯氏定氮法进行测定;采用范氏纤维测定法测定中性洗涤纤维(NDF)和酸性洗涤纤维(ADF);采用蒽酮-硫酸比色法测定水溶性碳水化合物含量(WSC);培养基培养微生物后计数;利用高效液相色谱仪分析有机酸;氨态氮含量(NH3-N)采用苯酚-次氯酸钠比色法测定。【结果】与MW相比,X25中NH3-N含量显著降低(P < 0.05);X50中pH和NH3-N含量显著下降(P<0.05);X75中pH和NH3-N含量显著降低,乳酸与乙酸比(LA/AA)显著升高(P < 0.05);此外,相比于MW,X25、X50和X75显著降低丁酸含量(P<0.05)。在MW中,与对照组相比,添加C显著降低pH和NH3-N含量(P < 0.05),显著增加乳酸(LA)含量和LA/AA(P<0.05)。在X25中,与对照组相比,添加C显著降低pH(P<0.05),提高LA含量(P<0.05);添加R显著降低NH3-N含量(P<0.05)。在X50中,与对照组相比,添加C显著降低pH和NH3-N含量(P < 0.05),添加B显著降低NH3-N含量(P<0.05)。在X75中,与对照组相比,添加C能够显著降低pH和NH3-N含量(P<0.05)。DM、NDF和ADF含量随小麦秸秆混合比例的增加而显著增加(P<0.05);相比之下,CP随小麦秸秆混合比例的增加而显著降低(P<0.05)。与MW相比,X25、X50和X75显著提高了 WSC含量(P<0.05)。在X25中,与对照组相比,添加C显著降低了NDF和ADF含量(P<0.05);在X50中,相比于对照组,添加B和C显著降低NDF含量(P<0.05);在X75中,相比于对照组,添加B、C和R显著降低NDF和ADF含量(P<0.05)。【结论】混合农副产物(西瓜皮﹕蚕豆荚﹕啤酒糟=1﹕3﹕4)单独青贮发酵品质较差,农副产物和小麦秸秆混合青贮能够改善发酵品质,小麦秸秆和农副产物(西瓜皮﹕蚕豆荚﹕啤酒糟=1﹕3﹕4)比例为50%﹕50%和75%﹕25%时为最佳混合比例;从营养品质来看,小麦秸秆和农副产物(西瓜皮﹕蚕豆荚﹕啤酒糟=1﹕3﹕4)比例为25%﹕75%和50%﹕50%时为最佳混合比例;综合考虑发酵品质和营养价值,小麦秸秆和农副产物(西瓜皮﹕蚕豆荚﹕啤酒糟=1﹕3﹕4)最适宜的混合比为50%﹕50%,添加C能够进一步提高发酵品质,改善营养成分。  相似文献   
69.
This study was conducted to assess changes in soil properties of a soil that received a one-time application (360 Mg ha?1) of fluidized bed combustion material (FBCM) 23 years earlier. Soil samples were taken at three depths (0–10, 10–20, and 20–30 cm). Samples were also collected from an adjacent field with the same soil type for control. Hot nitric acid and Mehlich 3 extractions were used for total and extractable elements. Analyses indicated improvement in soil physical and chemical properties after 23 years of FBCM application. For example at the 20- to 30-cm depth, soil pH values increased from 4.9 to 7.7, whereas calcium concentrations increased from 0.23 to 1.52 g kg?1 with FBCM amendment. In most cases, metal concentrations were less with FBCM amendment. Results from this study demonstrated that soil physical and chemical improvements from FBCM were maintained even 23 years after an extremely high application of FBCM.  相似文献   
70.
A field experiment evaluated the effects of surface applications of two industrial by-products (sugar foam and phosphogypsum) to an acidic Ultisol of the temperate zone in Spain to ameliorate topsoil and subsurface acidity and potential aluminium (Al) toxicity. The by-products were applied in single and combined amendments and at two different rates. Two years after their application, it was determined that applications at a low rate of sugar foam and sugar foam + phosphogypsum increased the pH and the exchangeable calcium (Ca) and reduced the exchangeable Al in the surface horizon of the soil while only a significant reduction of exchangeable Al was obtained in the subsurface horizon. Long-term amelioration of acidity and potential Al toxicity were only achieved upon the addition of these treatments at high rate. The addition of sugar foam at a high rate provides an effective practice for long-term acidity amelioration from the surface downward.  相似文献   
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