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41.
K. S. Venturini M. F. Sarcinelli M. A. Baller T. C. Putarov E. B. Malheiros A. C. Carciofi 《Journal of animal physiology and animal nutrition》2018,102(4):1077-1087
Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM—control diet based on poultry by‐product meal (PBM); GM—a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%—diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%—diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non‐starch polysaccharides of SPC produces an ingredient with mostly non‐fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. 相似文献
42.
Efficacy of essential oils combination on performance,ileal bacterial counts,intestinal histology and immunocompetence of laying hens fed alternative lipid sources 下载免费PDF全文
Asma Mousavi Amir Hossein Mahdavi Ahmad Riasi Masoud Soltani‐Ghombavani 《Journal of animal physiology and animal nutrition》2018,102(5):1245-1256
This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n‐6 to n‐3 fatty acids) fed to the animals during an 80‐days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p < 0.01) and the antibody titre against Newcastle virus (p < 0.05) but also led to reductions in liver relative weight (p < 0.05) and feed conversion ratio (p < 0.05). Moreover, the mixture of herbal essential oils brought about declines in hepatic relative weight, heterophile to lymphocyte ratio (p < 0.05) and intestinal pathogen populations (p < 0.01). Mention must also be made of the improvements it made in spleen weight (p < 0.01), antibody titres against SRBC (p < 0.01) and Newcastle virus (p < 0.05), villus height to crypt depth ratio (p < 0.01), goblet cell numbers (p < 0.05), lamina propria lymphatic follicle diameters (p < 0.01) and feed conversion ratio (p = 0.06). It may be claimed that the enhancements observed in the performance of laying hens fed fish oil and 200 mg/kg of the blend of essential oils could have potentially been associated with improved intestinal health indices as well as cellular and humoral immune responses. 相似文献
43.
采用水蒸气蒸馏法、超临界CO2萃取法和低温冷冻粉碎法等不同加工方法制备烧鸡风味复合辛香料深加工产品精油、油树脂和超微粉,并对其进行了风味成分的GC-MS对比分析.试验结果表明:3种辛香料深加工产品的风味成分存在差异,α-蒎烯、β-松油烯、桉叶油醇、γ-松油烯、丁香酚为三者共有成分、但含量存在差异,而有些成分为两者共有或... 相似文献
44.
为筛选最适合芽菜培养的小豆品种,以‘白红8号’为试材,设置3种生长调节物质(乙酰水杨酸、乙烯利和6-苄氨基腺嘌呤(6-BA))的各6个浓度(0.0、0.1、0.2、0.3、0.4、0.5 mmol/L;0、20、30、40、50、60 mg/L和0、2、3、4、5、6 mg/L)喷施处理,测定其生物特性(上胚轴长度、上胚轴直径、萌发率、鲜重、干重和产出比)、营养成分(可溶性蛋白和可溶性糖)及抗氧化等特性。结果表明:3种生长调节物质喷施处理都能够提升其营养价值,在乙烯利喷施浓度为50 mg/L,‘白红8号’小豆芽苗菜中各营养成分、酶活性及抗氧化性等均可达到最大值,显著提高了其营养价值。因此,为提高生产中小豆芽苗菜的产量和营养价值,最终确定乙烯利喷施浓度为50 mg/L效果最佳。 相似文献
45.
46.
港口原油装船VOCs大气环境影响探讨 总被引:1,自引:0,他引:1
收集了原油装船VOCs的估算方法,认为原油装船时VOCs排放量为0.012%,VOCs浓度为0.1kg/m3。采用SCREEN3对其环境影响进行分了析,结果表明:下风向最大浓度出现在400m 处,浓度值7.99mg/m3,直到2700m处,浓度值才小于1mg/m3,直到10000m处,浓度值仍为0.14mg/m3,原油装船VOCs的大气环境影响较大。 相似文献
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49.
Contribution of Different Organs to Grain Filling in Durum Wheat under Mediterranean Conditions I. Contribution of Post‐Anthesis Photosynthesis and Remobilization 下载免费PDF全文
Under Mediterranean conditions, drought affects cereals production principally through a limitation of grain filling. In this study, the respective role of post‐anthesis photosynthesis and carbon remobilization and the contribution of flag leaf, stem, chaff and awns to grain filling were evaluated under Mediterranean conditions in durum wheat (Triticum turgidum var. durum) cultivars. For the purpose, we examined the effects of shading and excision of different parts of the plant and compared carbon isotope discrimination (Δ) in dry matter of flag leaf, stem, chaff, awns and grain at maturity and in sap of stem, flag leaf, chaff and awns, this last measurement providing information on photosynthesis during a short period preceding sampling. Source–sink manipulations and isotopic imprints of different organs on final isotope composition of the grain confirmed the high contribution of both carbons assimilated by ears and remobilized from stems to grain filling, and the relatively low contribution of leaves to grain filling. Grain Δ was highly and significantly associated with grain yield across treatments, suggesting the utilization of this trait as an indicator of source–sink manipulations effects on grain yield. Chaff and awns Δ were better correlated with grain Δ than stem and leaf Δ, indicating that chaff were more involved in grain filling than other organs. Moreover, in chaff, sap Δ was highly significantly correlated with dry matter Δ. These results suggest the use of Δ for a rapid and non‐destructive estimation of the variation in the contribution of different organs to grain filling. 相似文献
50.
《Soil Use and Management》2018,34(1):72-84
Soya bean [Glycine max (L.) Merr] yields >6719 kg/ha (100 bu/ac) have only recently and infrequently been achieved. Quantifying soil property differences between high‐ and average‐yielding areas can help to further identify non‐plant‐related properties contributing to soya bean yield potential. The objective of this study was to evaluate the effects of region and soil depth on soil property differences between high‐ and average‐yielding areas. In each of the seven regions of the ‘Grow for the Green’ yield contest in Arkansas, prior to or just after harvest in 2014 and 2015, soil samples were collected from the top 20 cm of one contest high‐yield (HY ) area that was in close proximity to an average‐yield (AY ) area. Across all regions and both years, soya bean yields differed (P < 0.05) between yield areas, averaging 4701 and 5498 kg/ha in AY and HY areas, respectively. Averaged across soil depth and years, numerous soil properties differed (P < 0.05) between HY and AY areas within at least one of seven regions. Total soil C content was at least 20.2% greater in the HY than in the AY area in three of seven regions. Extractable soil P content was, on average, 19.4 kg/ha greater in HY than in AY areas in three of the seven regions. Results from this study have the potential to help producers better understand soil properties that contribute to or hinder achieving ultra‐high (>6719 kg/ha) soya bean yields. 相似文献