市售皮蛋、咸蛋卫生质量调查研究

为调查市售蛋制品的卫生质量,试验采用感官检验、半微量定氮法分别对某地区市售皮蛋、熟咸鸭蛋进行了抽样检测,并测定了皮蛋的pH值。结果表明:熟咸鸭蛋的新鲜度合格率只达到80%;皮蛋的pH合格率为93.3%,而感官检查合格率只有73.4%,皮蛋的挥发性盐基氮值在9.43～23.10mg/100g范围内。     

虎斑乌贼喷墨卵与正常卵的比较

为了探明虎斑乌贼喷墨卵对孵化及胚胎发育的影响,采用单因子实验研究了喷墨卵与正常卵的孵化率、培育周期、孵化周期、初孵幼体体质量,并比较了剥膜喷墨卵、剥膜正常卵、喷墨卵、正常卵4种类型卵的幼体生长和存活率。结果显示,虎斑乌贼喷墨卵和正常卵的孵化率无显著差异,喷墨卵的孵化率为90.1%±1.5%,正常卵的孵化率为87.9%±0.7%;两种卵的初孵幼体体质量也无显著差异,喷墨卵的初孵幼体体质量为(0.18±0.01)g,正常卵的初孵幼体体质量为(0.17±0.01)g;两种卵的培育周期、孵化周期均无显著差异,喷墨卵的培育周期为(34.67±0.89)d,孵化周期为(14.33±0.44)d,而正常卵的培育周期为(35.33±0.44)d,孵化周期为(14.67±0.67)d。而剥膜喷墨卵、剥膜正常卵、喷墨卵、正常卵4种类型卵的幼体存活率差异显著,剥膜喷墨卵和剥膜正常卵的存活率明显小于喷墨卵和正常卵,而剥膜喷墨卵和剥膜正常卵之间、喷墨卵和正常卵之间的存活率无显著差异;4种类型的幼体日均增长量和增重量差异显著,剥膜喷墨卵和剥膜正常卵的幼体日均增长量和增重量明显小于喷墨卵和正常卵,而剥膜喷墨卵和剥膜正常卵之间、喷墨卵和正常卵之间的幼体日均增长量和增重量无显著差异。     

Disinfection of Sparus aurata eggs with glutaraldehyde

This study was conducted to determine suitable conditions fordisinfecting eggs of gilthead sea bream (Sparus aurata)with glutaraldehyde. Effects of the developmental stage (4–8 cells,morula, blastopore closure or heart beating), of the concentration (C = 200,300or 400 ppm) and of the duration of the glutaraldehyde treatment (T= 2 to 10 min) were investigated. Before the blastopore closurestage, egg manipulation and treatment induced mortality. After this stage, thetoxicity of the glutaraldehyde treatment was negligible if the value of theproduct C × T was less than 1000. Above this value, the percentage ofhatching and of normal larvae decreased and the percentage of imprisoned larvaeincreased. Toxic effects of glutaraldehyde varied according to the egg qualityat the time of the treatment. It was concluded that 200 ppmglutaraldehyde for 4 min, at the blastopore closure stage or attheheart beating stage, were acceptable conditions for disinfecting gilthead seabream eggs at 18 °C.     

Elimination of adhesiveness in eggs from the white sturgeon,Acipenser transmontanus: Chemical treatment of fertilized eggs

Chemical elimination of the adhesive jelly coat in live Acipenser transmontanus eggs was investigated. Following fertilization, urea/sodium chloride (NaCl) or sodium sulphite (Na₂SO₃) treatment followed by a tannic acid wash, successfully removed the adhesive layer. In hatchery incubators, urea/NaCl-tannic acid treatment resulted in an increase in the number of hatched larvae over Na₂SO₃-tannic acid treatment. This treatment resulted in a hatch at least as great as silt-treated control eggs. The decrease in manual labor and time required for de-adhesion of sturgeon eggs as well as the high percentage of hatched larvae indicate that the urea/NaCl treatment is superior to the manual silting method.     

Disinfection of Sparus aurata eggs with glutaraldehyde

This study was conducted to determine suitable conditions fordisinfecting eggs of gilthead sea bream (Sparus aurata)with glutaraldehyde. Effects of the developmental stage (4–8 cells,morula, blastopore closure or heart beating), of the concentration (C = 200,300or 400 ppm) and of the duration of the glutaraldehyde treatment (T= 2 to 10 min) were investigated. Before the blastopore closurestage, egg manipulation and treatment induced mortality. After this stage, thetoxicity of the glutaraldehyde treatment was negligible if the value of theproduct C × T was less than 1000. Above this value, the percentage ofhatching and of normal larvae decreased and the percentage of imprisoned larvaeincreased. Toxic effects of glutaraldehyde varied according to the egg qualityat the time of the treatment. It was concluded that 200 ppmglutaraldehyde for 4 min, at the blastopore closure stage or attheheart beating stage, were acceptable conditions for disinfecting gilthead seabream eggs at 18 °C.     

Sperm-activating proteins obtained from the herring eggs

Spermatozoa of the Pacific herring, Clupea pallasii, were immotile in a solution of isotonic to seminal plasma, but swimming was initiated in a hypertonic solution such as 60% water. The motility of herring spermatozoa became active in the presence of freshly ovulated eggs, suggesting that ovulated eggs release the sperm-activating proteins, which are prerequisite to successful fertilization. Five species of herring sperm-activating proteins (HSAP) with different pI values (4.8, 4.9, 5.0, 5.1 and 5.4) were purified from the egg-conditioned medium by gel filtration and isoelectric focusing. Molecular mass of the HSAP (pI=5.1), the major species of the five HSAPs, was determined to be 8.1 KDa by mass spectrometry. Complementary DNA clones encoding herring sperm-activating proteins were isolated from a herring ovarian complementary DNA library and amino acid sequences were deduced. The herring sperm-activating protein(s) is a secretory product(s) with strong homology to Kazal-type trypsin inhibitors, such as mammalian acrosin inhibitors. The sperm-activating proteins were globally distributed in the outermost layer of the egg chorion and its gene was expressed in the follicle cells that surround developing oocytes. Both HSAPs and HSAP fragment (HSAP-E) could induce the membrane depolarization and increase in the intracellular Ca²⁺ concentration of herring spermatozoa. These results suggest that, in the Pacific herring, trypsin inhibitor like proteins are synthesized in the follicle cells, secreted, accumulated in the egg chorion during oocyte development and released into the milieu at spawning to activate the motility of spermatozoa at the time of gamete interaction.     

The toxicity of iodophors to salmonid eggs

Investigations made into the toxic effects of iodophor treatment of salmonid eggs confirm that presently recommended iodophor treatments are well within safety limits. The toxicity levels of one iodophor were established for eyed eggs over a wide range of concentrations and pH. With newly fertilized eggs it was shown that, provided the manufacturer's recommended methods are followed, no significant losses are to be expected. However, with higher concentrations of iodophor, a differential toxicity occurred that depended on the hen fish used. The cause of the differential toxicity may be related to the ‘age’ of the egg within the hen.     

Induced maturation and development of pinfish eggs

Pelagic eggs of pinfish (Lagodon rhomboides), a common marine teleost found along the Atlantic coast of the southeastern United States, were induced to mature with mammalian gonadotropins and steroid hormones. The eggs were artificially fertilized and subsequent development of the eggs and yolk-sac larvae appeared normal. Yolk-sac larvae at 18°C utilized 50% of the yolk stores in 15 h, and of the oil droplet in 17.4 h.     

Development of wolffish eggs at different temperature regimes

Embryonic development of common wolffish (Anarhichas lupus L.) was studied at constant temperatures 5.0, 7.0, 9.0, 11.0, 13.0 and 15.0°C. Duration of development from egg activation to several morphological stages including 50% hatching was determined. At 5.0–11.0°C, the survival rate of eggs to hatching ranged from 51 to 88% with a tendency to increase at 5.0 and 7.0°C. Morphological anomalies, bacterial contamination and large mortalities were observed in eggs incubated at 13.0 and 15.0°C. The period of hatching lasted from 10 to 50 d in different egg groups. Embryo length and yolk sac volume at identical morphological stages of development showed only slight relation to temperature. At lower temperatures newly hatched larvae were longer and at more advanced stages of ontogeny. Normal numbers of fin rays in larvae (mean values 74 for dorsal fin and 46 for anal fin) were observed at 5.0 and 7.0°C and in most larvae at 9.0°C. At 11.0 and 13.0°C, many rays were absent, with mean values for dorsal fin 60 and 39 respectively and for anal fin 28 and 4 respectively. The approximate upper limit for normal development of fin rays appeared to be 9.0 °C.     

Chemical treatment of lobster eggs against epibiotic bacteria

Eggs of the European lobster, Homarus gammarus (L.), were exposed to malachite green (5, 10, 15 mg 1^–1: 10 min), glutaraldehyde (50, 100, 150 mg 1^–1: 3 min) and iodine as Buffodine^TM (50, 100, 150 mg 1^–1: 10 min). The efficiency of the treatments was tested by incubating eggs individually in wells of multiwell dishes with TSB agar for 14 days after exposure. In order to find any effect on viability, batches of 30 eggs from each of three females were incubated artificially in a recirculation system for 19 days and repeatedly exposed to the disinfectants. Iodine as Buffodine (150 mg 1^–1) was the only treatment that resulted in a significant decrease of the bacterial growth on lobster eggs, but the treatment also resulted in inhibited hatching compared with the control group. Thus, our results indicate that treatment with 150mg^–1 iodine as Buffodine could be a strategy for reducing bacterial growth on lobster eggs when massive egg mortality due to bacteria is otherwise unavoidable. The treatment could, however, lead to decreased viability of larvae due to inhibited hatching.     

Flat fish eggs,larvae and their development

Studies on development of eight species of flat fishes (Psettodes erumei, Brachypleura novae-zeelandiae, Pseudorhombus arsius, Bothus myriaster, Synaptura albomaculata, S. commersoniana, Cynoglossus arel and C. monopus) were carried out with plankton collections and with laboratory reared larvae. The development stages of Cynoglossus arel and C. monopus from egg to metamorphosis are described.     

大眼鰤鲈鱼的长途运输

１９９３年５月２４日从加拿大萨斯卡切温省环境及资源管理Ｆｏｒｔ所属ＦｏｒｔＱｕ，ＡＰｅｌｌｅ鱼苗孵化场移运大眼　鲈发眼鱼卵１００万粒，鱼苗４万尾，采用尼龙袋充氧气，低温保存等方法，途经４４小时的长途空运，到哈尔滨市水产研究所，发眼鱼卵运输成活率４０％，鱼苗运输成活率９０％。     

Impact of bacteria on short-term storage of salmonid eggs

Unfertilized eggs of steelhead, Oncorhynchus mykiss (Walbaum 1792), were stored at a low temperature (～0°C) with antibiotics (penicillin and streptomycin) for up to 22 days and fertility assessed. Unfertilized eggs of chinook salmon, Oncorhynchus tshawytscha (Walbaum 1792), were stored at a low temperature (～0°C) either with or without antibiotics for up to 24 days and fertility assessed. There were no significant decreases in fertility under these conditions. Steelhead eggs were maintained at 4°C for up to 15 days with or without added bacteria and with or without gentamicin. Gentamicin inhibited bacterial growth during storage at 4°C and its use resulted in a less pronounced decline in fertility with storage. These results suggest that low temperatures and antibiotics play an important role in extending the period over which salmonid eggs can be successfully stored.     

海水鱼卵子石蜡切片的方法改进

利用戊二醛作固定液,通过对脱水、透明、透蜡、染色技术的改进,在海水鱼卵子石蜡切片过程中,省略了卵膜剥离程序,获得了良好的切片效果。     

合浦珠母贝三倍体的卵诱导四倍体

将合浦珠母贝三倍体的卵与二倍体的精子授精,用０．５μｇ／ｍＬ细胞松弛素Ｂ抑制精卵第一极体的释放诱导四倍体。研究了处理起始时间及持续时间对胚胎孵化率和四倍体诱导率的影响及幼虫的生长及存活。实验结果表明：持续时间与胚胎孵化率呈负相关,而与四倍体诱导率呈正相关,持续时间一般为１５￣１８ｍｉｎ,处理起始时间一般在第一极体出现前３￣５ｍｉｎ。在胚胎期,四倍体诱导率平均为２０％。在幼虫培养阶段,幼虫死亡严重,     

虹鳟鱼卵形态观察初步研究

2001年8、9、10、11、12月和2002年12月进行了不同时间虹蹲鱼卵卵径的变化和不同颜色虹蹲鱼卵的吸水前后变化、采卵数、受精率的观察研究。结果表明：经方差分析体长、体重与卵径无相关性，而卵径与时间、水温有一定的相关性(r＝0．8354，r=—0．7634)；橘红色、淡黄色卵在吸水前后变化、采卵数、受精率等差异不大，橘红色卵的质量略高于淡黄色卵。     

鲑鳟鱼类养殖技术之三花羔红点鲑发眼卵长途运输技术

花羔红点鲑是原产于黑龙江省东南和吉林东部长白山区的野生鲑科红点鲑属鱼类,目前正在进行家化养殖试验,本文初步探讨了其发眼卵长途运输技术.     

Fatty acid analysis of fish eggs without solvent extraction

Two techniques for preparing samples of Coryphaena hippurus fish eggs for fatty acid analysis were compared. The first technique involved direct methylation of samples containing either 50 or 100 fresh eggs. The second involved methylation of the solvent-extracted fat from samples containing 1000 eggs each that had either been freeze dried or oven dried. The fatty acid profiles of small samples of fresh eggs were similar to profiles obtained from the solvent-extracted fat of much larger samples of dried eggs. In addition, the fatty acid profiles of 100 fresh egg samples were higher in both saturated and unsaturated fatty acids than the profiles obtained from 100 freeze-dried or oven-dried eggs. The technique of using direct methylation of fresh egg samples without solvent extraction has three main advantages: it requires less preparatory and analytical work, it can be used with much smaller samples, and it is less destructive to the material being analyzed. Direct methylation can also be used to prepare samples of small organisms such as algae, rotifers (Brachionus sp.), and brine shrimp (Artemia sp.) for fatty acid analysis.     

抱卵青虾的选购、暂养和运输

人工繁育青虾苗种的最佳时间是每年的5月中下旬至6月份，但此时气温偏高，不利于抱卵虾的选购、暂养和运输。笔者在近几年的青虾育苗实践中，深感这项工作既烦琐又重要，须耐心细致地解决好每一环节的问题方能保证育苗工作的顺利进行。现就2003～2004年相关工作总结如下。