Freezing equine semen: the effect of combinations of semen extenders and glycerol on post-thaw motility

Objective   We evaluated combinations of two commercial semen extenders and three concentrations of glycerol to determine the combination that yielded the highest post-thaw sperm motility.
Design   A randomised 2 × 3 block design was used.
Procedure   Semen was collected from four stallions (6 collections per stallion). The sample was diluted with either a dried skim-milk glucose extender (EZ Mixin Original Formula) or a chemically defined, milk-free diluent (INRA 96), and each was used in combination with 2%, 3% or 4% glycerol in standard commercial freezing medium. Sperm motility was assessed by microscopy in fresh and post-thaw semen.
Results   There was a significant difference between the two extenders in the motility of spermatozoa after cryopreservation (48.9% for INRA 96; 38.6% for EZ Mixin OF; P < 0.0001). Glycerol at 4% in freezing medium yielded the highest post-thaw motility, significantly better than 2% ( P < 0.05). Three of four stallions had significantly higher post-thaw motility using INRA 96 relative to EZ Mixin OF ( P < 0.01), and two of four stallions had significantly higher post-thaw motility using 4% glycerol ( P < 0.05). The combination of INRA 96 and 4% glycerol in freezing medium gave the highest average post-thaw motility of 51.5%.
Conclusion   In this study, INRA 96 combined with 4% glycerol yielded an average recovery of progressively motile sperm consistently above the 35% target.     

Incidence of lymphoma in a captive-bred colony of hamadryas baboons (Papio hamadryas)

Objective   To assess the incidence of lymphoma and wasting-related deaths in the National Baboon Colony of Australia and relate it to the presence of simian T-cell lymphotrophic virus 1 (STLV-1) infection.
Design and procedure   The records of all animals that had died since establishment of the National Baboon Colony in Australia were reviewed retrospectively. The clinical signs and histopathological findings were recorded and assessed to determine the involvement of lymphoma in the deaths. The presence of STLV-1 was recorded if known and correlated with the STLV-1 status of the colony.
Results   Of the deaths from disease or illness, 53% were diagnosed as or suspected to be lymphoma, occurring in mature animals with no sex predisposition. The most common presentation was rapidly occurring generalised lymphadenomegaly.
Conclusions   This study has described a relatively high prevalence of lymphoma in a colony of captive-bred baboons, and it is evident that STLV-1 may play a role in the disease. Management practices in baboon colonies need to take into account the possible presence of STLV-1 and aim to reduce the transmission of the virus by preventing sexual contact between positive and negative animals. Lymphoma needs to be considered as one of the more common causes of wasting and death.     

深水网箱箱体用超高强经编网的物理性能研究

2010～2012年期间在东海水产研究所对深水网箱箱体用超高强经编网(以下简称UHSPE经编网)的物理性能进行了研究。结果表明,规格为"UHSPE-267tex×3-45"的3股UHSPE经编网的网目强力、网片纵向断裂强力、网片横向断裂强力、网片纵向断裂伸长率、网片横向断裂伸长率分别为143.6daN、465.2daN、441.6daN、27.1%、50.4%;在具有相同网目长度、网目连接点结构及网片热定型条件的条件下,规格为"UHSPE-267tex×3-45"的3股UHSPE经编网与规格为"PA-23tex×78-45"的普通78股锦纶经编网(以下简称PA经编网)的物理性能有明显差异,前者有较高的网片强力,而后者具有较大的断裂伸长率;使用3股UHSPE经编网比使用78股PA经编网更经济,其在深水网箱的推广应用上具有可行性。     

超高分子量聚乙烯绳索伸长的测定

本研究对绳索伸长测定的原理、设备、试样和2种试验方法的试验步骤及结果的表示进行了探索.对5个试样用2种试验方法所得出的结果进行比较分析.超高分子量聚乙烯纤维的断裂伸长率为常规化纤的1/8左右,制成绳索后产生塑性伸长.超高分子量聚乙烯绳索在拉伸速度不超过250mm/min、分别以额定断裂强力75%和50%的载荷作用下,伸长率平均分别为6.09%和1.91%,平均塑性伸长为4.10%.经回归方程分析得出了超高分子量聚乙烯绳索的伸长率ε与相对强力ψ呈幂函数关系,由此推算得出试样的断裂点伸长率平均为7.5%.     

Effects of protein hydrolysate in weaning diets for Atlantic cod (Gadus morhua L.) and Atlantic halibut (Hippoglossus hippoglossus L.)

The study aims to test whether predigested dietary protein enhances the utilization of formulated diets at weaning, and also whether it stimulates intestinal maturation. In this study, Atlantic cod [ Gadus morhua L.; 41 days posthatch (dph)] and Atlantic halibut [ Hippoglossus hippoglossus L.; 63 days postfirst feeding (dpff)] were weaned onto diets with graded levels of protein hydrolysate. By increasing the inclusion of dietary protein as hydrolysate from 0 to 400 g kg⁻¹, cod increased the rate of survival from 7 ± 1% to 18 ± 2% (82 dph; regression, P =  4*10⁻⁷). In halibut, the survival rate decreased from 57 ± 9% to 22 ± 7% as the inclusion of protein in the form of hydrolysate increased from 0 to 450 g kg⁻¹ (119 dpff; regression, P =  8*10⁻⁵). Growth was not affected in any of the species. Results in specific activities of the intestinal enzymes leucine aminopeptidase (LAP) and alkaline phospatase (AP) supported the results in survival in halibut and partly also in cod, by showing increased activities in groups with increased survival ( anova , P <  0.05). The lower optimal level of hydrolysed protein in halibut than in cod is suggested mainly because of a slower feeding practice in halibut, which allows more extensive nutrient leaching before ingestion.     

椰浆中椰子蛋白的提取、分离和鉴定

为了更好地了解市售椰浆中椰子蛋白质量状况,本研究以市售的10种椰浆为样品,采用反向高效液相色谱（reversed-phase high performance liquid chromatography,RP-HPLC）及十二烷基磺酸钠-聚丙烯酰胺凝胶电泳（sodium laurylsulfonate-polyacrylamide gel electrophoresis,SDS-PAGE）对提取蛋白进行分析,采用基质辅助激光解吸电离飞行时间串联质谱（matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry,MALDI-TOF/TOF-MS）对蛋白进行鉴定。结果表明：椰浆RP-HPLC约在10.4 min和11.9 min分别出现1个色谱峰,大多数样品峰面积大小都与蛋白标签含量一致,SDS-PAGE条带数量和颜色的深浅与RP-HPLC得到的峰面积结果一致,个别样品标签含量高,SDS-PAGE能分离出的蛋白条带数量也较多,但RP-HPLC的椰子蛋白峰面积小,经MALDI-TOF/TOF-MS鉴定,部分条带没有鉴定出椰子有关的肽段或蛋白。研究结果为椰浆蛋白的食品安全与质量控制提供了方法参考和示范。     

浅水湖泊溶存甲烷浓度（dCH4）对气温升高及季节变化响应特征

揭示温度升高对浅水湖泊中溶存甲烷（CH4）浓度的影响,可为全球碳评估提供重要的理论支撑,为更好地应对气候变化对浅水湖泊碳排放的影响提供数据支持。采集梁子湖表层沉积物和湖水,并置于塑料水缸（沉积物厚度为10 cm,注入深度为1 m的湖水）,设置比周围环境温度升高3.5℃的升温组(W)和不进行温度设置的控制组(C),每组6个平行,2022年1月完成系统设置后放置两个月后开始采样,分别在春季（3、4月）和夏季（7、8月）进行,计算甲烷浓度,同时测量水温（T）、pH、电导率（EC）、溶解氧（DO）、总氮（TN）、总磷（TP）、正磷（PO43-）、氨态氮（NH4+）、硝态氮（NO3-）和亚硝氮（NO2-）、Chl-a、溶解性有机碳（DOC）等参数,并分析甲烷浓度和环境因子的相关关系。结果显示,W组的甲烷浓度与C组之间差异不显著,W组的甲烷浓度总体上低于C组;夏季甲烷的浓度显著高于春季,说明温度是影响甲烷排放的重要因素;Spearman相关性分析和逐步回归分析表明甲烷浓度主要与水温、营养盐含量（TP、PO43-、DOC）、pH、DO和电导率（EC）有关,其中,季节性温度变化是影响水体溶存甲烷浓度的最主要环境因子。     

芽期NaCl胁迫下不同基因型芝麻的反应差异研究

通过芽期NaCl胁迫研究了不同浓度NaCl对芝麻种子成苗及幼苗生长的影响,分析了0．4％ NaCl胁迫下不同基因型芝麻的反应差异。结果表明：（1）0～0．4％的NaCl浓度对芝麻种子成苗率影响较小,在NaCl浓度为0．6％～0．8％时表现为成苗率下降;芽长和简易活力指数均随NaCl浓度的增加而不断下降;根长和苗鲜重则因品种不同表现有异,部分品种随NaCl浓度增加呈先升后降趋势,部分品种则表现为不断下降趋势,不同芝麻品种表现差异较大。（2）所有参试品种在0．4％的NaCl浓度胁迫下在根长、芽长、苗鲜重、简易活力指数等测定指标上均表现出下降较为明显,认为0．4％的NaCl浓度胁迫可以作为芝麻种质资源耐盐性筛选鉴定的参考浓度。（3）聚类分析结果将39份种质资源明显聚为两类,即包含12份种质的耐盐类和包含27份种质的不耐盐类。（4）参试的改良品种（系）与地方种质耐盐性差异不大,地方种质的耐盐性指标的多样性指数要大于改良品种（系）,即在NaCl胁迫下地方种质所表现的基因型差异要大于改良品种（系）。     

转基因抗病棉花品系密度与肥料互作效应研究

在田间试验条件下 ,研究了转基因抗病棉品系 960 9不同密度与不同肥料的互作效应。结果表明 :以N2 62 D1 65处理时叶面积系数变化合理 ,单株干物质积累增加 ,并利于向生殖器官的分配 ,产量高 ;同一施肥水平 ,密度的增产效应为 3 .8%～ 1 9.8% ,同一密度下 ,肥料的增产效应为 5.2 %～ 3 1 .5% ,肥料的增产效应大于密度的增产效应。