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为研究超声波预处理对全株青贮玉米品质的影响,设置空白对照组、超声处理组（5、10、15、20、25 min）和乳酸菌对照组进行青贮玉米品质研究。结果表明：15 min和20 min超声处理后,全株玉米青贮饲料感官评定属于优良级。与对照组相比,超声处理后饲料的pH和氨氮比分别降低7.71%和7.82%,乳酸和乙酸含量分别提高52.14%和97.22%,干物质、水溶性碳水化合物、粗脂肪和粗蛋白质含量分别提高6.31%、15.76%、19.65%和16.34%,中性洗涤纤维、酸性洗涤纤维和酸性洗涤木质素含量分别显著降低26.10%、22.44%和29.08%。综合以上指标,15 ~ 20 min超声处理能明显提高全株玉米的青贮质量。 相似文献
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《中国家禽》2020,(7)
为最大限度提高全蛋液的乳化性,以全蛋液为研究对象,进行单因素及响应面试验,对乳化性专用全蛋液超声杀菌工艺条件进行优化。在保证微生物致死率大于90%的条件下,优化乳化性专用全蛋液的超声功率(130～390 W)与处理时间(10～30 min)。结果显示:随超声功率增大和时间延长,乳化性先增大后减小,分别在超声功率为260 W和超声时间为20 min时达到较大值(1.455和1.456)。考虑到实际生产和响应面结果,较优工艺参数为超声功率278 W、处理时间19 min,在此条件下,乳化性为1.486,较未经处理全蛋液的乳化性提高3.6%,较巴氏杀菌蛋液的乳化性高7.07%。研究表明:超声波杀菌较巴氏杀菌更适宜生产乳化性专用全蛋液。 相似文献
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种子在长期的贮存过程中会发生不可逆的衰老现象,从而导致品质和产量下降。合理的修复处理可以提高老化种子的活力和幼苗质量。本研究采用四因素[超声温度、超声时间、抗坏血酸(ascrobic acid, AsA)浓度、抗坏血酸浸种时间]三水平L_9(3~4)正交试验,对人工老化的梭梭(Haloxylon ammodendron)种子进行超声波和AsA混合处理,研究超声波和AsA对种子萌发和幼苗生理特性的影响,分析其是否可以修复老化造成的损伤,并选出最优的处理条件。结果表明,适当剂量的超声波和AsA能够对老化种子产生修复作用,处理后种子发芽率、发芽势、发芽指数和幼苗长度均得到显著提高(P 0.05),种子浸出液电导率、丙二醛(MDA)含量和脯氨酸含量下降,可溶性蛋白含量增加,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)等保护酶活性增强,其中超声温度为影响种子活力的最重要因素。研究分析得出,老化梭梭种子的最优修复处理条件为:超声温度25℃,超声时间20 min,AsA浓度300 mg·L~(–1),AsA浸种时间24 h。 相似文献
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灌水对沙漠绿洲区甘草生长动态和产量的影响 总被引：1，自引：1，他引：1
为研究灌水对沙漠绿洲区甘草（Glycyrrhiza uralensis）生长动态和产量的效应,本研究设2 700（W1）、3 600(W2)、4 500(W3)、5 400(W4)、6 300(W5)和7 200(W6) m3/hm2 6个灌水处理。结果表明,灌水明显促进甘草茎叶、根的生长。处理W4、W5和W6株高显著高于W1、W2和W3（P<0.05）,主茎生长速度W6处理较W1快60％,较W2快33％;W3、W4、W5和W6处理地上部干质量显著高于W1（P<0.05）,干物质积累速度W3处理较W1快11％;根长、芦径、根干质量随灌水量增加而增加,灌水量超过5 400 m3/hm2则表现下降趋势,处理W3和W4根干质量最高,在根快速生长期W3和W4处理的一年龄和二年龄根干质量增加速度分别较W1快50％和35％。灌水4 500和5 400 m3/hm2,一年龄甘草和二年龄甘草根产量均达到较高水平,但前者灌水效率较后者高,可节水900 m3/hm2。 相似文献
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为优化浮萍多糖的提取工艺,基于单因素试验结果对影响浮萍多糖提取率的三个显著因素及水平：料液比(1∶40、1∶50、1∶60)、超声时间(40 min、60 min、80 min)和超声功率(300 W、350 W、400 W)进行了研究。以浮萍多糖提取率为响应值,运用Design-Expert软件进行响应面设计并开展试验,通过工艺优化确定浮萍多糖的最佳提取条件为料液比1∶40.06、超声时间79.58 min、超声功率341.37 W,此条件下浮萍多糖提取率的理论值可达到1.188%;验证试验的浮萍多糖提取率为1.125%,与理论值仅相差0.063%。优化后的提取工艺条件准确可靠,可用于实际操作。 相似文献
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试验研究了高压处理(100～400 MPa,10～60℃)对牛奶蛋白浓缩物(MPC)粉末溶解度的影响。未经高压处理时,新鲜的MPC粉末20℃时的溶解度为66%。在环境温度(-20℃)条件下保存6周,溶解度下降10%,而保存12个月之后,其溶解度继续下降至原溶解度的50%以下。综合压力和温度因素,在喷雾干燥前采用压力为200MPa,温度为40℃作用于该浓缩物,有利于提高MPC粉末的溶解度。这种压力和温度的综合效应可使其初始的冷水溶解度提高至85%。此种条件下,该粉末在环境温度条件下保存6周溶解度不变,保存12个月后仍可保留其85%的初始溶解度。生产和贮存过程中MPC粉末溶解度的提高归因于其表面成分的改变,这种表面成分的改变是由干燥之前进行的高压处理引起牛奶中非胶束酪蛋白浓度的升高导致的。酪蛋白酸钠和乳清蛋白分离物混合制成的高蛋白粉(蛋白含量为95%)的溶解度与由超滤/渗滤乳制得的MPC粉末(蛋白含量为85%)相比有所提高,证实胶束酪蛋白对溶解度具有不利作用。以上结果表明,利用高压处理提高牛奶中非胶束酪蛋白的含量或使用酪蛋白酸钠和乳清蛋白混合物可作为提高高蛋白奶粉溶解度的措施。 相似文献
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该文研究了热水处理对番石榴常温条件下贮藏品质与生理变化的影响。番石榴果实经过45℃ 5min、45℃ 10 min、50℃ 5 min和50℃ 10 min等4种不同条件的热水处理后,结果显示出50℃ 5min热水处理对番石榴的保鲜效果最好。50℃ 5min热水处理可以抑制番石榴的呼吸强度、质膜相对透性、丙二醛（MDA）含量、多酚氧化酶（PPO）和过氧化物酶（POD）活性,提高保护酶苯丙氨酸解氨酶（PAL）活性,延缓番石榴采后衰老速度,有利于延长番石榴的贮藏时间和保持番石榴果实原有的风味品质。 相似文献
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F Van Wambeke 《British poultry science》1984,25(4):583-587
Semen from commercial breeder males was diluted two-fold and stored for 6 and 24 h at 2 to 3 degrees C. For each storage period, groups of caged dwarf broiler breeder hens from the same strain were inseminated with 300, 200 or 100 x 10(6) spermatozoa. Three replicates of 15 birds were inseminated per treatment. Control hens were inseminated with 150 x 10(6) fresh, undiluted spermatozoa. Inseminations were performed for 5 consecutive weeks during a first (32 to 36 weeks of age) and for 6 consecutive weeks during a second experimental period (42 to 47 weeks). During weeks 33 to 36 of the first period, only 24 h storage and 100 x 10(6) spermatozoa produced lower (P less than 0.05) hatchability of all eggs set than the control (84.4 compared to 88.6%). During weeks 43 to 47 of the second period, no significant differences between treatments were observed. Embryonic mortality, measured at different periods during incubation, was not affected by the storage time or the number of spermatozoa inseminated. 相似文献
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1. The effect of vitamin E (α‐tocopheryl acetate) in turkey diets on the oxidative stability of raw and cooked turkey burgers and on the retention of α‐tocopherol during refrigerated (4°C) or frozen (‐20°C) storage was investigated. One hundred and two, one‐day‐old T‐8S turkey poults were divided at random into 3 groups of 34 animals each and fed on either a basal diet (normal commercial turkey diet) supplemented with 20 mg α‐tocopheryl acetate/kg (control) or fed an α‐tocopherol supplemented diet containing 300 (E300) or 600 (E600) mg α‐tocopheryl acetate/kg for 21 weeks.
2. Dietary supplementation with α‐tocopheryl acetate significantly reduced TBARS numbers in both raw and cooked burgers during refrigerated and frozen storage.
3. The mean values of α‐tocopherol in raw and cooked burgers stored at 4°C did not change during storage.
4. In the case of both raw and cooked samples stored at ‐20°C, the α‐tocopherol values decreased from 5.67 to 3.54 and from 3.56 to 2.30 μg/g in the raw burgers from turkeys from the E600 and E300 treatments, respectively, after 4 months storage. The values decreased from 5.60 to 2.88 and from 3.29 to 1.85 μg/g in cooked burgers from turkeys from the E600 and E300 treatments, respectively, after 5 months storage. 相似文献
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W J Foreyt 《Journal of the American Veterinary Medical Association》1986,189(9):1065-1067
Fresh fecal specimens from deer were examined for nematode eggs (primarily Haemonchus and Ostertagia), using a flotation technique (sugar, sp gr = 1.27), and then were reexamined for up to 200 days after storage in 2.5, 5, or 10% formalin, absolute methyl alcohol, or 70% ethyl alcohol at room temperature (20 C) or after storage without preservative at 4, 0, or -20 C. For long-term storage, 10% formalin was the best fixative for recovery of eggs (compared with the rate of recovery of eggs from fresh feces). Approximately 50% of the strongyle eggs were detected in feces stored in formalin for 200 days. However, between days 3 and 10 of storage, the recovery rate was low (less than 50%), presumably due to ion binding. Alcohols were unsuitable for preservation, and storage at 0 or -20 C resulted in an egg recovery rate of less than 50%. Storage at 4 C for 50 days resulted in approximately 90% recovery of nematode eggs. Number of Parelaphostrongylus tenuis larvae recovered from fecal specimens stored in 10% formalin for 24 days was greater than that recovered from fresh fecal specimens. 相似文献
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Cryopreservation of testicular tissue has become a part of gamete preservation in wild animal post-mortem. Using domestic cats as a model for wild felids, this study aimed to (i) investigate the effect of temperature for testicular tissue storage on sperm quality; (ii) compare efficiency of freezing protocols; and (iii) evaluate properties of cryoprotective agents to protect testicular sperm quality. A pair of testes from each cat (n = 9) was cut into four pieces. Three randomly selected pieces were allocated to be (i) fresh controls; (ii) stored at 4 °C for 24 h; and (iii) stored at room temperature (28 °C) for 24 h. After storage, the testicular tissue from each group was cut into 10 small pieces. One piece was assigned to be a control while the others were assigned to three freezing protocols; -80 °C (n = 3), vitrification (n = 3) or two-step freezing (kept above liquid nitrogen vapour for 10 min and submerged in liquid nitrogen) (n = 3). Each of three pieces was frozen using dimethyl sulphoxide (DMSO), ethylene glycol (EG) or DMSO combined with EG. Sperm membrane (SYBR-14/EthD-1) and DNA (acridine orange) integrity were evaluated before and after cryopreservation. The storage of testicular tissue at room temperature decreased the percentage of sperm with intact membrane in fresh tissue (59.5 ± 30.5 vs 87.9 ± 7.0%, p < 0.05). DNA integrity was decreased after 24-h storage either at 4 °C or room temperature (p < 0.05). The two-step freezing resulted in a higher percentage of sperm with intact plasma membrane than the other techniques. Dimethyl sulphoxide, EG and DMSO combined with EG provided similar protection for the sperm membrane and DNA from cryodamages. In conclusion, storage of testicular tissue at 4 °C is necessary to maintain sperm membrane integrity during transportation of tissue for cryopreservation in the freezing laboratory. The results provide information for male gamete rescue in felid particularly when they die unexpectedly in the field where freezing facilities are not well equipped. 相似文献
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Evaluation of Citrate-Phosphate- Dextrose-Adenine as a Storage Medium for Packed Canine Erythrocytes 总被引：1，自引：0，他引：1
G. Sylvester Price DVM P. Jane Armstrong DVM MS Deborah A. McLeod DVM Cynthia A. Babineau Michael R. Metcalf DVM MS Louis C. Sellett MS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(3):126-132
Packed canine red blood cells (RBCs) stored in the anticoagulant-preservative solution citrate-phosphate-dextrose-adenine (CPDA-1) were studied at 1, 10, 20, 30, and 40 days. The extracellular concentrations of potassium and sodium, erythrocyte mean corpuscular volume, and osmotic fragility increased during storage (P less than 0.05). There was a decrease in the pH, plasma concentration of glucose, and erythrocyte concentrations of 2,3-diphosphoglycerate (2,3-DPG) and adenosine-5'-triphosphate (P less than 0.05). Erythrocyte 2,3-DPG concentration decreased by 54% within the first 24 hours of storage (P less than 0.001). Posttransfusion viability (PTV) decreased from 90% on day 1 to 46% on day 40 (P less than 0.05). The PTV of the RBCs stored for 10 and 20 days complied with the Food and Drug Administration (FDA) standard. Although there are marked biochemical and hematologic changes in stored packed red blood cells (pRBCs), 20-day-old units may be expected to be of acceptable quality. The sharp decrease in 2,3-DPG concentration suggests a reduction in oxygen carrying capacity in erythrocytes stored as pRBCs. Hyperkalemia occurs during storage of pRBCs and does not appear to be associated with high intraerythrocytic potassium concentrations. 相似文献
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以‘纳罗克’狗尾草（Setaria sphacelata ‘Narok’）种子为供试材料,采用不同浓度（5~25 mmol·L-1）和不同时间（5~25 min）的草酸处理,探究外源草酸对非洲狗尾草种子萌发（发芽率、发芽势、发芽指数和活力指数）及生理特征（可溶性糖含量、超氧化物歧化酶（Superoxide dismutase,SOD）,过氧化物酶（Peroxidase,POD）,过氧化氢酶（Catalase,CAT）活性、丙二醛（Malondialdehyde,MDA）含量）的影响,并研究了外源草酸对储藏0~4年狗尾草种子的生理特性及幼苗生长的影响。结果表明：草酸处理对收获当年狗尾草种子的萌发具有促进作用,随着处理浓度和时间增加至25 mmol·L-1,25 min,收获当年的种子可达到破眠效果;采用25 mmol·L-1,25 min的条件处理不同储藏年限的种子,显著提高收获当年种子的SOD和CAT活性,增加0~2年种子幼苗的根长,降低种子MDA含量,POD活性随储藏年份的延长逐渐降低。草酸处理后不同储藏年份种子的综合评分为0年>1年>2年>3年>4年。推荐采用外源草酸处理条件为：25 mmol·L-1,25 min,可有效促进收获当年和储藏1年种子的萌发及生长。 相似文献
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Amy M Grooters Amy Whittington Mae K Lopez Michelle N Boroughs Alma F Roy 《Journal of veterinary diagnostic investigation》2002,14(4):288-294
The purpose of this study was to evaluate the effects of sample handling, storage, and culture techniques on the isolation of Pythium insidiosum from infected equine tissues. Tissue and kunker samples obtained immediately posteuthanasia from a horse with subcutaneous pythiosis were used to assess the effects of sample type (kunkers vs. tissues), media type (selective vs. nonselective), storage technique, and storage time on P. insidiosum isolation rate. Overall, isolation rates were higher from fresh kunkers (94.6%) and stored kunkers (76.4%) than from fresh tissues (8.3%) or stored tissues (4.6%). Isolation of P. insidiosum also occurred more often on antibiotic-containing media than on nonselective media for both fresh and stored samples. For samples that were stored for 1-3 days prior to culture, P. insidiosum isolation rates were highest for the following techniques: kunkers stored at room temperature and plated on selective media (100%), kunkers stored at 4 C and then plated on either nonselective (91.7%) or selective (95.8%) media, kunkers stored on cold packs and then plated on either nonselective (93.8%) or selective (100%) media, kunkers stored in ampicillin solution and plated on selective media (100%), and kunkers stored in ampicillin/gentocin solution and plated on selective media (87.5%). For samples stored for 4-5 days, P. insidiosum isolation rates were highest for kunkers stored at 4 C and then plated on either nonselective (81.3%) or selective (87.5%) media, kunkers stored in ampicillin solution and then plated on selective media (87.5%), and kunkers stored in ampicillin/gentocin solution and plated on selective media (87.5%). Results of this study suggest that optimal isolation rates of P. insidiosum from infected equine tissues are achieved by culturing fresh kunkers on selective media. For samples that cannot be processed immediately, acceptable handling techniques include storage at room temperature for up to 3 days, refrigeration for up to 5 days, shipping on cold packs, and storage in antibiotic solution, each combined with subsequent inoculation on selective media. 相似文献
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Santé-Lhoutellier VS Théron L Cepeda M Grajales A Gatellier P 《British poultry science》2008,49(3):308-314
1. The present study compared the ability of native, heat-treated and aged turkey breast muscle proteins to undergo proteolysis by digestive tract proteases. 2. Domestic turkey toms were slaughtered under laboratory conditions. Breast muscles were excised immediately post mortem; one was placed under conditions to develop exudative meat by maintaining the muscle at 40 degrees C for at least 30 min and the other was refrigerated under commercial conditions. 3. Meat was collected and stored for 7 d at 4 degrees C. Breast samples removed at d 0 and d 7 were frozen and stored at -80 degrees C until used for determination of solubility, protein surface hydrophobicity and protein oxidation through carbonyl content. Measurements of pepsin and trypsin/chymotrypsin activities were performed in vitro on myofibrillar proteins. 4. Storage increased carbonyl content in control samples while the oxidation increase was not significant in heat-treated myofibrillar protein. Hydrophobicity was not affected by storage time or treatment or protein solubility. 5. Storage significantly increased trypsin + chymotrypsin activity only in the control group. The activities of pepsin and trypsin + chymotrypsin were negatively correlated with protein surface hydrophobicity. 相似文献