铬在渔业中应用的研究进展

综述了铬在渔业中应用的研究进展,包括铬作为水产养殖饲料添加剂,对水生生物生长、毒性和生理活性的影响,及铬对养殖水体的污染、对渔业生物的危害以及检测方法等等,并提出了今后的研究展望。     

拟除虫菊酯和有机磷农药对三种扇贝稚贝的急性毒性效应

采用静水实验法测定拟除虫菊酯类和有机磷类农药对三种扇贝稚贝的急性毒性效应.结果表明:联苯菊酯对海湾扇贝、栉孔扇贝和虾夷扇贝稚贝24 h的LC50的分别为1.460、1.662和2.909 mg/L;辛琉磷对海湾扇贝、栉孔扇贝和虾夷扇贝稚贝24 h的LC50的分别44.598、182.167和39.334 μg/L;马拉...     

天津港口疏浚淤泥悬浮物对海洋动物的急性毒性效应

研究了不同浓度的悬浮物对鲈鱼和梭鱼幼体的毒性效应。实验结果表明:疏浚淤泥悬浮相对其效应明显。21℃和24℃试验水温时,悬浮物对鲈鱼幼苗的急性毒性实验结果分别为:96hLC50为1 711.2mg/L、1 052.8mg/L;安全浓度分别为:171.12、105.28mg/L;悬浮物对梭鱼幼苗的急性毒性实验结果分别为:96h LC50为453.6、168.1mg/L;安全浓度分别为:45.36、16.81mg/L。随温度、悬浮物浓度的升高,毒性效应呈增强趋势。     

巢式PCR法鉴定猪早期胚胎性别的研究

根据猪SRY基因序列设计合成2对巢式PCR引物作为性别鉴定引物,根据猪β-珠蛋白基因序列设计了一对引物作为内标引物建立了猪胚胎性别鉴定的PCR反应体系。公猪可以扩增出187bp的SRY基因片段和255bp的β-珠蛋白基因片段,母猪只能扩增出255bp的β-珠蛋白基因片段。由于巢式PCR只需3～8个细胞就可以在紫外灯下看到扩增结果,而常规PCR则需要较多的细胞,所以胚胎性别鉴定时使用巢式PCR效果更好。     

鲍活体倍性检测技术的研究

在生物有机体中,一个细胞核中所含的DNA总量对于某种类有机体是一定的。利用流式细胞仪(FCM)测量细胞中的DNA含量,可以用来鉴别有机体的倍性。本研究分别取杂交鲍[即皱纹盘鲍(Haliotis discus hannai)×盘鲍(Haliotis.discus discus)]的一小块触手、足肌,设计不同的振荡时间、不同的DAPI染色时间、不同的取样部位,制备成不同的细胞悬液检查样品;用PA-Ⅱ型倍体分析仪测定其倍性,以探讨其对倍性检测效果的影响。试验结果表明:振荡的最适时间为1.5～2.0 min,染色的最适时间为4.0～5.0 min;取材部位的不同对检测结果无显著影响。     

中华鳖群体间编码MHCⅠ类分子α2结构域基因的克隆及序列分析

2004年1月至2005年4月在江苏靖江市的长江沿岸用定置张网采集刀鲚261尾。清洗后的矢耳石在60℃烤箱中烘烤24h，干燥冷却后用电子天平称重，精确到0．01mg。成对t检验显示，左右矢耳石间的重量无显著差异（P〉0．05），选用左矢耳石为研究对象。用直线、幂函数和多项式等确定各类参数间的最佳拟合公式。结果表明，长江口刀鲚的耳石重量在不同年龄组间的重叠相对较少，大小相近的个体，年龄大即生长慢的比年龄小即生长快的耳石重量大，不同龄组间耳石重量有显著的差异（P〈0．05）。按年龄组以耳石重量与相应的体长作图，可初步判断所观测年龄的可靠性。分析耳石重量的频率分布，能分离出体长相近但年龄不同的个体，其结果与依据耳石年轮观测的基本一致，耳石重量与年龄呈显著的线性相关性（P〈0．05）。用该相关性估算年龄，与从耳石上直接读取的年龄并无显著差异（P〉0．05）。因此，矢耳石重量可以作为直接确定长江口刀鲚年龄或作为验证依据钙化组织判断年龄准确性的有效手段。     

黄鳝的年龄鉴定和生长

用黄鳝的耳石,脊椎骨和舌骨三种材料相对照,对其年龄进行了鉴定。认为舌骨是黄鳝年龄鉴定比较理想的材料,并首次提出尾舌骨也可以作为年龄鉴定的材料。分析了体长,体重的分布,分别用幂函数关系和直线回归方程计算体长与体重的关系式,并进行比较。     

Litopenaeus vannamei (Boone) post-larval survival related to age, temperature, pH and ammonium concentration

Transport of post‐larvae shrimp used in aquaculture is an important element of successful cultivation because of the potential for stress during stocking procedures. To find optimum transport conditions, several bioassays were performed in the laboratory to evaluate survival of whiteleg shrimp Litopenaeus vannamei 5–30‐day‐old postlarvae under conditions similar to those encountered during transport from the hatchery to nursery and shrimp ponds. Postlarvae were exposed for 4 h to different temperatures and pH levels ammonia concentrations. Survival was significantly reduced after a 4 h exposure to pH 9 and was inversely related to temperature with or without 7 mg L^?1 of ammonia. The 15‐ and 20‐day‐old postlarvae had higher survival rates than other ages. The lowest survival occurred in alkali conditions (pH 9), with 7 mg L^?1ammonia at 30 and 32°C. To assure optimal survival of postlarvae during transfer from the hatchery to the nursery and shrimp ponds, we recommend temperatures below 28°C, pH no higher than 8, no ammonia and post‐larval age at least 15 days.     

Gene Expression in Black Tiger Prawns Following Intramuscular Injection of β-gal Plasmid

Gene expression in black tiger prawns (Penaeus monodon) was studied following intra-muscular injection of CMVGal plasmid into the second abdominal segment. We used an in situ staining technique to detect -gal expression in one- and three-month-old injected prawns. We found that only one of the three-month-old prawns expressed the marker gene (2 days after injection), and the site of expression was confined to the sixth abdominal segment away from the injection site. We repeated the experiment on a new batch of three-month-old prawns, but using fluorometric determination technique. This time we found that -gal expression was detected (6/42) at the site of injection after 2, 7, and 14 days. In two other test samples, transgene expression was detected in the sixth abdominal segment only, further confirming the possibility of injected DNA dispersal. The results of the study also suggest that direct gene transfer is a feasible technique in black tiger prawns.