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1.
The experimental diets containing five levels of creatine supplementation, namely control (N = 0 g/kg creatine), B1 (1.00 g/kg glycine), B2 (0.40 g/kg creatine), B3 (0.80 g/kg creatine) and B4 (1.20 g/kg creatine) were tested to red tilapia up to apparent satiation 3 times a day for 56 days. After the feeding trial, fish were stressed by air exposure for challenge test against stress. The results described that creatine supplementation improved final body weight, feed conversion ratio (FCR) and protein retention. Creatine supplementation decreased blood glucose, cholesterol and triglyceride levels (p < .05), indicating more effective usage of non‐protein energy. Furthermore, creatine supplementation also increased plasma insulin levels and upregulated IGF‐1 and GLUT4 gene expressions in the liver significantly; it also improved robustness against stress, which was shown by higher superoxide dismutase, higher postchallenge survival and plasma cortisol, malondialdehyde and lower glucose levels. In conclusion, creatine supplementation at a dose of 0.289–0.389 g/kg diet escalated fish growth and improved robustness against stress via improving the SOD activity in red tilapia.  相似文献   
2.
为研究益生菌发酵红薯渣对肉牛生长性能、养分表观消化率的影响,采用单因素随机设计试验,选择体重相近、健康的育肥肉牛40头随机分成4组,每组10个重复,每个重复1头,试验1组饲喂基础日粮,试验2、3、4组分别用10%、15%、20%益生菌发酵红薯渣替代饲粮中的玉米,预试验10 d,试验期60 d。结果表明:(1)试验3、4组的平均日增重较1组比分别提高16.9、14.1%(P<0.05),试验2、3、4组的平均采食量均高于1组(P>0.05);试验3、4组的料重比较1组比分别降低14.9%、12.4%(P<0.05);(2)试验2、3、4组干物质、蛋白质、钙、磷的表观消化率均高于1组(P 0.05);试验3、4组的中性洗涤纤维、酸性洗涤纤维表观消化率较1组比分别提高12.7%、11.0%、18.9%、16.4%(P<0.05)。综上,益生菌发酵红薯渣替代饲料中15%玉米,可以提高肉牛的生长性能和养分表观消化率。  相似文献   
3.
选取泌乳天数、体重、产奶量相近的荷斯坦高产泌乳牛340头,随机分为试验组和对照组两组,每组170头。试验时间共28d,对照组全期饲喂全混合配方日粮(TMR),试验组分四阶段进行,每阶段7d,分别饲喂以10%、20%、30%、40%粉碎大麦粉替代玉米的TMR。结果发现:随着大麦粉替代玉米比例的增加,试验组采食量呈现下降趋势,其中30%、40%替代期采食量极显著低于对照组(P<0.01);与对照组相比,大麦粉替代不同比例玉米对奶牛产奶量影响不一致,20%、30%替代期产奶量增加0.4、0.3kg/d,10%、40%替代期分别下降0.6、0.7kg/d,但差异均不显著(P>0.05);试验组10%、40%替代期乳脂率极显著高于对照组(P<0.01),而20%、30%替代期乳脂率与对照组差异不显著(P>0.05);试验组10%替代期乳蛋白率极显著高于对照组(P<0.01),而30%、40%替代期显著低于对照组(P<0.05),20%替代期乳蛋白率较对照组下降0.012个百分点,但差异不显著(P>0.05)。综上所述,饲粮中用大麦粉替代20%比例的玉米饲喂奶牛,在不影响采食量、乳脂率、乳蛋白率情况下可提升产奶量并降低饲养成本,从而提高经济效益,为最佳替代比例。  相似文献   
4.
为改善大豆分离蛋白膜的性能,将纳米氧化锌(Zno Nanoparticles,Zno NPs)和葡萄皮红(Grape-Skin Red,GSR)加入大豆分离蛋白(Sov ProteinIsolate,SPI)中制备SPI/ZnO NPs/GSR复合膜,对复合膜的性能进行表征。结果表明当葡萄皮红、ZnO NPs和大豆分离蛋白以1:2:25的质量比制备复合膜时,相对于SPI/ZnO NPs膜,葡萄皮红可提高ZnO NPs和大豆分离蛋白的相容性,改善ZnO NPs在SPI膜中的分散性,并与ZnO NPs发挥协同作用提高SPI膜的机械性能、耐水性能和热稳定性(P0.05)。SPI/ZnO NPs/GSR复合膜相比较于SPI膜,拉伸强度从1.37 MPa升至3.28 MPa,熔点从194℃升至231℃,含水率从34.41%降至25.37%,水蒸气透过系数从5.57×10~(-12) (g·cm)/(cm~2·s·Pa)降至4.74×10~(-12) (g·cm)/(cm~2·s·Pa)。此外,复合膜对金黄色葡萄球菌和大肠杆菌表现出优异的抗菌性能,抑菌圈直径随着活性成分的添加呈上升趋势(大肠杆菌:SPI 膜无,SPI/ZnO NPs 膜 2.29 cm,SPI/ZnO NPs/GSR 膜 2.36 cm;金黄色葡萄球菌:SPI 膜无,SPI/ZnO NPs 膜 2.32 cm,SPI/ZnO NPs/GSR膜2.42 cm),在活性包装应用中具有极大潜力。研究结果为大豆分离蛋白基薄膜的生产应用提供参考。  相似文献   
5.
本研究通过探索红心火龙果营养品质和产量对稻壳有机肥施用量的响应,旨在为红心火龙果的施肥管理提供参考。以5年生‘台农二号’红心火龙果为供试材料,设置3个稻壳有机肥施用水平(低施肥量L:22 500 kg/hm2;中施肥量M:45 000 kg/hm2;高施肥量H:90 000 kg/hm2),调查火龙果全年各批次果实的还原糖、可溶性蛋白、维生素C(Vc)、可溶性固形物、花青素、可食率及产量。结果表明:(1)稻壳有机肥施用量对部分批次火龙果的果实营养品质、果数及产量影响显著;(2)存在显著差异的批次中,增加有机肥施用量对火龙果花青素、可溶性固形物、Vc、果数以及产量具有显著的促进作用,其中相较于L处理,花青素含量在7月19日批次中M处理增大5.59%,可溶性固形物在9月6日批次中H处理增大6.95%,Vc含量在10月23日批次中M处理和H处理分别增大24.11%和14.29%,果数在9月6日批次中M处理和H处理分别提高372.73%和172.73%,产量在9月6日批次中M处理和H处理分别提高373.44%和165.63%(P<0.05);(3)还原糖和可溶性蛋白含量在差异显著的批次中随有机肥施用量的增加而减少;(4)在3个有机肥施用量下,L处理的经济效益最好,同时营养品质和可食率较优。综上所述,调控稻壳有机肥施用量显著改善红心火龙果果实营养品质和可食率。  相似文献   
6.
The mutation T3811 → G3811 (TG3811) discovered in the myostatin gene of the Blonde d’Aquitaine breed is suspected of contributing to the outstanding muscularity of this breed. An experiment was designed to estimate the effect of this mutation in an F2 and back-cross Blonde d’Aquitaine × Holstein population. By genotyping all known mutations in the myostatin gene, it was ensured that the TG3811 mutation was indeed the only known mutation segregating in this population. Fifty-six calves (43 F2, 13 back-cross) were intensively fattened and slaughtered at 24.0 ± 1.4 wk of age. The effects of the mutation were estimated by comparing the calves with the [T/T] (n = 18), [T/G] (n = 30), and [G/G] (n = 8) genotypes. Highly significant substitution effects (P < 0.001), above + 1.2 phenotypic SD, were shown on carcass yield and muscularity scores. Birth weight (P < 0.001) was positively affected by the mutation (+0.8 SD) but not growth rate (P = 0.97), while carcass length (P = 0.03), and fatness (P ≤ 0.03) were negatively affected (–0.5 to –0.7 SD). The characteristics of the Triceps brachii muscle were affected by the mutation (P < 0.001), with lower ICDH activity (oxidative) and a higher proportion of myosin type 2X muscle fibers (fast twitch). The effects of the TG3811 mutation were similar to those of other known myostatin mutations, although the Blonde d’Aquitaine animals, which are predominantly [G/G] homozygous, do not exhibit extreme double muscling.  相似文献   
7.
More than 7000 red algae species have been classified. Although most of them are underused, they are a protein-rich marine resource. The hydrolysates of red algal proteins are good candidates for the inhibition of the angiotensin-I-converting enzyme (ACE). The ACE is one of the key factors for cardiovascular disease, and the inhibition of ACE activity is related to the prevention of high blood pressure. To better understand the relationship between the hydrolysates of red algal proteins and the inhibition of ACE activity, we attempted to identify novel ACE inhibitory peptides from Pyropia pseudolinearis. We prepared water soluble proteins (WSP) containing phycoerythrin, phycocyanin, allophycocyanin, and ribulose 1,5-bisphosphate carboxylase/oxygenase. In vitro analysis showed that the thermolysin hydrolysate of the WSP had high ACE inhibitory activity compared to that of WSP. We then identified 42 peptides in the hydrolysate by high-performance liquid chromatography and mass spectrometry. Among 42 peptides, 23 peptides were found in chloroplast proteins. We then synthesized the uncharacterized peptides ARY, YLR, and LRM and measured the ACE inhibitory activity. LRM showed a low IC50 value (0.15 μmol) compared to ARY and YLR (1.3 and 5.8 μmol). In silico analysis revealed that the LRM sequence was conserved in cpcA from Bangiales and Florideophyceae, indicating that the novel ACE inhibitory peptide LRM was highly conserved in red algae.  相似文献   
8.
Colonization of red raspberry flowers and fruit by Botrytis cinerea was determined during 2017–2018 growing seasons under commercial fungicide application programmes used for grey mould management in northwestern Washington, USA. Colonization of flowers and fruit was assessed qualitatively (incidence, %) and quantitatively (abundance, number of colonies) by recovering B. cinerea from surface-disinfested samples. Both incidence and abundance of flower colonization were significantly lower than fruit colonization in both untreated and fungicide-treated plots. Incidence of flower colonization did not differ significantly between untreated and fungicide-treated plots (43% vs. 45%, respectively). In contrast, significantly greater colonization incidence was detected at green fruit stage in untreated compared to fungicide-treated plots (96% vs. 77%, respectively). Ripe fruit had the greatest colonization incidence among the three stages sampled and colonization was not significantly different between untreated and fungicide-treated plots (100% vs. 92%, respectively). Similarly, colonization abundance of flowers did not differ significantly between untreated and fungicide-treated plots (1.0 colonies per colonized flower in both treatments), but colonization abundance of green and ripe fruit was decreased 2.3- and 2.1-fold, respectively, in fungicide-treated plots. DNA fingerprinting analysis of the pathogen revealed that different multilocus genotypes colonized flowers and fruit within the same inflorescence and that genotypic diversity increased through time, suggesting independent infection events. Overall, our results demonstrate that under current environmental conditions, raspberry flowers may not be the exclusive or major route of infection for grey mould of red raspberry in northwestern Washington. Implications of current findings for management and further research are discussed.  相似文献   
9.
Lycopene, one of the strongest natural antioxidants known and the main carotene in ripe tomato, is very important for human health. Light is well known to be one of the most important environmental stimuli influencing lycopene biosynthesis; specifically, red light induces higher lycopene content in tomato. However, whether blue light promotes lycopene synthesis remains elusive and exactly how light stimulation promotes lycopene synthesis remains unclear. We applied supplemental blue and red lighting on tomato plants at anthesis to monitor the effect of supplemental blue and red lighting on lycopene synthesis. Our results showed that supplemental blue/red lighting induced higher lycopene content in tomato fruits; furthermore, we found that the expression of key genes in the lycopene synthesis pathway was induced by supplemented blue/red light. The expression of light signaling components, such as red-light receptor phytochromes (PHYs), blue-light receptor cryptochromes (CRYs) and light interaction factors, phytochrome-interacting factors (PIFs) and ELONGATED HYPOCOTYL 5 (HY5) were up- or down-regulated by blue/red lighting. Thus, blue and red light increased lycopene content in tomatoes by inducing light receptors that modulate HY5 and PIFs activation to mediate phytoene synthase 1 (PSY1) gene expression. These results provide a sound theoretical basis for further elucidation of the light regulating mechanism of lycopene synthesis in tomatoes, and for instituting a new generation of technological innovations for the enhancement of lycopene accumulation in crop production.  相似文献   
10.
中国盛产小浆果,但小浆果不容易保存且季节性强,因此附加值较低,为了提高小浆果的产品附加值,本试验研究了小浆果酒的发酵工艺,并探讨了解决出汁率低,果酒单宁含量过少所导致的货架期短、挥发酸高、不易澄清等问题。试验以小浆果红树莓为原料,经破碎、酶解、澄清、发酵、过滤等工艺,制得了发酵型红树莓果酒,经过单因素和正交试验优化发酵工艺,确定最佳的酿造工艺条件。结果表明,酶解过程采用25 g/kL EMACLAR果胶酶和25 g/kL EVZYM果胶酶低温酶解14 h,与传统方式对比,出汁率提高了10%;发酵过程,红树莓果汁初始糖度19%,利用VP5为酿酒酵母,接种量为10%,发酵温度22℃;发酵结束后使用树脂降酸,澄清过程使用30 g/100 L硅藻土、15 g/100 L明胶复合澄清的方式。在此工艺条件下得到的红树莓果酒酸度爽口,色泽清亮、均匀,有明显的树莓香气和纯正的发酵型香气。  相似文献   
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