纤维素酶纯化方法与原生质体的制备

以绿色木霉为材料,经稻草粉固体发酵、浸提得纤维素酶粗酶液,然后经硫酸铵分级沉淀,超滤,SephadexG-75柱层析3种方法纯化,利用得到的纤维素酶,分别制备幼嫩番茄叶片的原生质体。结果发现高度纯化的纤维素酶几乎得不到原生质体,而经超滤后的纤维素酶制备原生质体效果最佳。     

清香梨幼树和成年树光合特性比较研究

用CIRAS-1便携式光合作用测定系统测定了清香梨幼树和成年树叶片的光合特性,结果表明:清香梨幼树叶片的净光合速率(Pn)、气孔导度和蒸腾速率显著高于成年树,而幼树和成年树叶片的胞间CO2浓度(C i)、气孔阻止值和水分利用率差异不显著。在低光强、低CO2浓度(Ca)或低C i下,梨幼树和成年树叶片的Pn差异较小,但随着光强、Ca或C i的增加,两者间Pn的差异明显加大。幼年树叶片的光补偿点、光饱和点、CO2补偿点、CO2光饱和点、表观量子效率、羧化效率、光合能力和RuBP最大生产速率均高于结果树。     

鸭病毒性肝炎高免卵黄抗体的研制

用DVH弱毒疫苗和DVH油乳剂苗免疫健康高产蛋鸡制备高免卵黄抗体,研究了高免卵黄抗体治疗雏鸭DVH的疗效。结果表明,高免卵黄抗体治疗DVH的疗效取决于卵黄抗体的中和效价、治疗时间和免疫途径。卵黄抗体的中和效价应达28.5以上,并且在感染DVH 24 h以内对雏鸭进行肌肉注射,免疫效果最好。     

水杨酸对大久保桃花及幼果生长的影响

[目的]研究水杨酸(SA)对大久保桃花授粉和幼果发育的影响。[方法]以大久保桃花粉和幼果为试材,研究水杨酸对花粉萌发、花粉管伸长和幼果纵横径生长的影响。[结果]0.0020、.020 mmol/L SA对花粉萌发有促进作用,而0.200 mmol/L SA处理的花粉萌发率明显低于对照;0.002 mmol/L SA处理其花粉管显著高于对照,起到了促进花粉管伸长的作用,0.200 mmol/L SA则抑制了花粉管伸长;0.002、0.0200、.200 mmol/L SA均对大久保桃幼果的生长存在不同程度的抑制作用,且随着SA浓度的增大抑制作用增强。[结论]不同浓度SA对大久保桃花及幼果生长存在不同影响。     

幼龄蓝孔雀日粮代谢率试验

采用全粪收集法对雌雄混群饲养的20只幼龄（5月龄）蓝孔雀日粮（粗蛋白质水平28．20％，总能水平18104．4kJ/kg)中能量、粗蛋白质、干物质、粗脂肪、无氮浸出物和粗纤维的代谢率进行了测定，其结果分别是：81．72％、59．80％、75．46％、46．73％、88．55％和58．71％。     

Characterization of β-N-Acetylhexosaminidase from rhizostomous jellyfish, Rhopilema asamushi, Mesogloea

β-N-Acetylhexosaminidase (EC 3.2.1.52) was purified from rhizostomous jellyfish mesogloea and characterized. Using two purification steps, this enzyme was purified up to 27.4-fold with a recovery rate of 46% compared with crude extract. The molecular weight of the enzyme was estimated to be about 136 kDa, composed of subunit molecular weights of 68 kDa. The enzyme activity was inhibited by SH-reagents, indicating that it contains a SH-group in its active site. The enzyme has a high affinity for pNPGlcNAc with Km value of 0.021 mM. The rate of hydrolysis of N-acetylchito-oligosaccharides tended to decrease with increasing degree of polymerization of the substrate. The parameters of k _cat were 92.0 s⁻¹ for pNPGlcNAc, 38.2 s⁻¹ for GlcNAc₂, 14.0 s⁻¹ for GlcNAc₃, 4.1 s⁻¹ for GlcNAc₄, 1.6 s⁻¹ for GlcNAc₅, 0.9 s⁻¹ for GlcNAc₆, respectively. These results suggest that this β-N-acetylhexosaminidase is an exo-fashion hydrolytic enzyme involved in chitin degradation. This revised version was published online in August 2006 with corrections to the Cover Date.     

兔眼越橘新梢转录组测序与分析

为研究兔眼越橘新梢中基因转录和抗氧化物代谢相关通路的基因表达,利用Illumina Solexa技术和生物信息学方法对兔眼越橘品种‘粉蓝’新梢进行转录组测序分析。结果表明,测序数据组装后共获得64 185条单体序列;将其与COG、KEGG、GO、NR和Swiss-Prot数据库比对后发现,共有37 900条单体与葡萄、桃、番茄、蓖麻、毛果杨、草莓等物种的基因具有同源性;基于COG数据库分析后可见,12 559条序列可归属其中,而转录类、复制-重组-修复类、翻译后修饰-蛋白质周转-分子伴侣类位居前列;基于KEGG数据库分析发现,19条抗氧化相关代谢通路中,黄酮类、苯丙素类代谢通路是活跃通路,叶酸类、类胡萝卜素、二苯乙烯类、二芳基庚酸类、姜酚、二萜类化合物的合成通路是部分支路活跃,而其他抗氧化相关通路基本无法产生预期功能成分。     

幼林间作大豆高产栽培技术

幼林间作大豆的关键技术是:选用适合幼林间作的春大豆早中熟高产和夏大豆高产类型新品种,在最佳间种时期播种,合理间作,增施肥料,加强田间管理,及时收获晾晒和脱粒,确保大豆优质高产高效.     

不同日龄幼獐活体取乳量与术后存活率的关系

[目的]探讨幼獐活体取乳的最佳日龄.[方法]2014年6～7月,在杭州富阳市养獐场开展幼獐活体取乳试验研究.[结果]随着幼獐日龄的增加,取乳量也随之增加,但相邻日龄之间差异不显著,相隔2d以上的幼獐取乳量存在显著差异.幼獐术后存活率呈现“两头低中间高”的特征.[结论]幼獐的最佳取乳时期是18 ～ 19日龄,而最佳取乳量为133～146 g.     

Chicory (Cichorium intybus L.) and cereals differently affect gut development in broiler chickens and young pigs

Dietary fiber, resistant to host-mediated digestion in the small intestine due to lack of endogenous enzymes, impacts many facets of animal health and is associated with gut development especially in young monogastrics. Furthermore, it can be used as in-feed antibiotic alternative. Chicory (Cichorium intybus L.) forage with high content of pectin (uronic acids as building blocks) is a novel class of dietary fiber that is chemically different from cereal grains (with high content of arabinoxylans). In the present study, we investigated effects of dietary inclusion of chicory forage on digestibility, gut morphology and microbiota in broilers and young pigs. In the chicken experiment, 160 1-d old broiler chicks were fed 3 nutritionally balanced diets for 30 d including a cereal-based diet and 2 diets with part of the cereals substituted with 60 and 120 g/kg chicory forage (CF60 and CF120), whereas in the pig experiment, 18 seven-wk old Yorkshire pigs were fed 3 diets for 18 d including a cereal-based diet and 2 diets with 80 and 160 g/kg chicory forage inclusion (CF80 and CF160). Our results showed that young pigs were capable to utilize chicory forage well with higher total tract apparent digestibility (TTAD) of all fiber fractions, particularly uronic acid, compared with the control (P < 0.01). In contrast, a decreased TTAD of all fiber fractions was observed in chickens fed on diet CF120 (P < 0.05). Moreover, diet induced changes in gut morphology were observed in the large intestine of chickens. The alteration of cecal mucosal thickness was further positively correlated with TTAD of non-starch polysaccharides (NSP) and its constituent sugars (P < 0.05). In addition, in pigs, terminal restriction fragment length polymorphism (T-RFLP) analysis of intestinal microbiota revealed substantial dietary effects (cereal control diet vs. chicory forage inclusion) on the relative abundance of 2 dominant bacterial phylotypes (Prevotella sp. vs. Roseburia sp.) respectively (P < 0.05). In conclusion, our data showed that chicory forage (Cichorium intybus L.), a novel dietary fiber source in animal nutrition, have potential beneficial properties as fiber ingredient in diets for both pigs and chickens.