Chemical Characterization of Testes Meals Made from Alaska's Seafood Processing Byproducts

ABSTRACT

Our objective was to produce a unique feed ingredient from underutilized walleye pollock (Theragra chalcogramma) and pink salmon (Oncorhynchus gorbuscha) testes. Protein content in meals from both species (72% and 80%, respectively) were above the values found in high quality herring meals (～70%), but both were poor in some essential amino acids, e.g., methionine. Additionally, both were good sources of the amino acid taurine (1.7 and 2.2% of meal, respectively). Pollock meal was very rich in phospholipids (82% of total lipids) and in DHA (28 mg/g meal) and EPA (18 mg/g meal), indicating potential as an ingredient in larval starter diets. The purine contents in both pollock and salmon testes meals were more than 10 times the concentrations found in other fish byproducts or commercial fishmeals. The high concentrations of purines found in these testes, especially in the salmon meal, make it an ideal candidate for an immune system stimulant when added to dietary formulations.     

Constructing the Ontology for Modeling the Fish Production in Pearl River Basin

This paper puts forward a construction method based on ontology for the Pearl River Basin fish production,to facilitate the domain knowledge analysis and information retrieval.By converting the concept...     

Nursery areas of Micromesistius poutassou and Sardina pilchardus unveil their reproductive strategies in the northwestern Mediterranean Sea

Winter conditions in the NW Mediterranean cause instability of the water column and non-geostrophic dynamics, such as vertical mixing and convection are significant. These events involve nutrient supply to the photic zone that can sustain high productivity. In this study, we aim to investigate the role of winter hydrodynamics on the spawning strategies of Sardina pilchardus and Micromesistius poutassou. Data were obtained on two oceanographic cruises (February 2017 and 2018) off the Catalan coast. The occurrence of S. pilchardus eggs very close to the coast indicated a clear preference of the species for spawning in coastal areas. Preflexion and postflexion larvae exhibited a slightly wider distribution showing a clear association with the cold, less saline and more productive coastal waters. Preflexion larvae of M. poutassou were found on the upper slope and over the shelf, being offshore limited by the shelf/slope front present all along the slope. The front would act as a barrier preventing their dispersion towards the open sea. M. poutassou larvae in advanced developmental stages were located close to the coast in the productive shelf waters, with instabilities of the front contributing to larval transport from offshore waters to the coast. The vertical distribution of both species showed high variability, not only related with the daily cycle or developmental stage, but also with the vertical structure of the water column. Overall, the results provide some clues on how the spawning strategies of both species may evolve under future scenarios of higher winter-stratification, because of the global warming.     

文洛型温室在工厂化养鱼系统的应用

文洛型温室采用三屋脊型钢结构、屋面四层结构(外遮阳幕布、聚碳酸酯中空板、内遮阳幕布和内保温幕布)、平板式彩钢复合板围护结构等,较好地解决了以往水产温室材料和结构中存在的肥梁、胖柱、重盖等问题;温室采用湿帘风扇室温调节系统,温水井补充加热和水处理系统,较好满足引种、育种、养殖和越冬管理等方面要求,实现了全年候养鱼生产。该温室生产运行3年证明,安全可靠,在山东尚属首创。该温室应用功能和经济技术指标较好,具有很高的应用推广价值。     

杂交鳜与鳜鱼、斑鳜肌肉营养成分和氨基酸含量比较

通过测定鳜鱼、斑鳜和杂交鳜的肌肉营养成分和18种氨基酸含量,结果表明：杂交鳜、斑鳜和鳜鱼的肌肉水分、脂肪、灰分的含量无显著差异（P〉0．05）,杂交鳜与斑鳜的肌肉蛋白质含量无显著差异（P〉0．05）,但均显著高于鳜鱼肌肉的蛋白质含量（P〈0．05）;鳜鱼、斑鳜和杂交鳜的18种氨基酸含量及其组成、18种氨基酸总量（TAA）、人体所需8种必须氨基酸总量（HEAA）及4种呈味氨基酸（天门冬氨孽、谷氨酸、甘氨酸和丙氨酸）的总量（FAA）均无显著差异（（P〉0．05）。     

Influence of mapping resolution on assessments of stream and streamside conditions: lessons from coastal Oregon,USA

• 1. Digital hydrographic data are commonly employed in research, planning, and monitoring for freshwater conservation, but hydrographic datasets differ in spatial resolution and accuracy of spatial representation, possibly leading to inaccurate conclusions or unsuitable policies for streams and streamside areas.
• 2. To examine and illustrate the potential for different hydrographic datasets to influence in‐channel and streamside characterizations, a study area in the US Pacific Northwest was chosen because 1:100 000, 1:24 000, and densified 1:24 000 hydrography are available and widely used in research and management for several species of Pacific salmon and trout at risk. The potential was examined for differences among the digital hydrographic datasets in: (1) spatial extent to influence estimated abundances of fish habitat, streamside buffer conditions, and fish distributions; and (2) spatial position to influence estimated streamside buffer conditions and estimated stream gradient.
• 3. The analysis of spatial extent found the total stream length represented by the 1:100 000 hydrography was approximately one half that of 1:24 000 hydrography and only one fifth that of densified 1:24 000 hydrography. The 1:100 000 and 1:24 000 networks differed significantly for 13 out of 18 fish habitat attributes, and the three hydrographic datasets differed significantly for many characteristics in streamside buffers; fish distributions mapped at 1:24 000 added 6–14% of stream length to 1:100 000 distributions. The analysis of spatial position found few differences between the 1:100 000 and 1:24 000 hydrography in streamside buffer characteristics but significant differences in channel gradient.
• 4. Overall, hydrographic datasets differed only slightly in spatial position but differed in spatial extent to the point of representing different populations of streams. If species inhabiting larger streams (greater mean annual discharge) are of interest, then results derived from studies based on 1:100 000 hydrography should prove useful. However, higher‐resolution hydrography can be critical when designing and implementing strategies to protect fish and other aquatic species at risk in smaller streams.

Copyright © 2008 John Wiley & Sons, Ltd.     

Effects of entrance design on catch efficiency of arabesque greenling traps: a field experiment in Matsumae, Hokkaido

ABSTRACT:   A field experiment was conducted in the Matsumae area of Hokkaido, Japan, during June and July 2002, to investigate the effects of different entrance designs on the catch efficiency of fish traps by fishing with commercial traps (entrance inclination angle [α] = 37°; funnel length of entrance [ L _f ] = 22 cm) and experimental traps. The experimental traps were of the same size and similar design as commercial traps, with different entrance inclination angles (trap E1: α = 46°; E2: α = 27°; E3: α = 0°; all L _f  = 22 cm) or funnel lengths (E4: α = 37°, L _f  = 8 cm). In total, 2200 fish during 200 trap hauls were captured. The catch was significantly higher using both traps E2 and the commercial trap than with trap E3 ( P  < 0.05), and the catch of trap E2 was higher than that of the commercial trap. There were no significant differences in mean fish body length or the frequency distributions of body length among trap types (E1, E2, E3 and commercial). The funnel length of the entrance also affected the catch of traps. Trap E4 had significantly higher catches than the commercial trap ( P  = 0.04) when traps were deployed for a 1-day soak time. Fish body length frequency distributions did not differ between trap E4 and the commercial trap. The results showed that catch can be greatly affected by trap entrance designs.     

气质联用法测定咸鱼中N-二甲基亚硝胺含量

建立了咸鱼中N-二甲基亚硝胺含量的气质联用分析方法。样品用丙酮/二氯甲烷(1∶2)提取,采用选择离子法(SIM)进行定性定量检测。本检测方法前处理简单快捷;线性范围宽,可达0~500μg/mL;重现性良好,回收率为84%~90.3%,相对标准偏差为2.4%~4.0%;灵敏度高,检测限为0.6 ng/g。     

布氏哲罗鲑年龄与生长的初步研究

本文根据鳞片生长环纹的计数,并同鳞片、脊椎骨、鳃盖骨等上的年轮相对照,对4龄内的布氏哲罗娃的年龄与生长进行了研究。其结果摘要如下:(1)布氏哲罗鲑鳞片上的环纹随年龄而变化:每月长出二圈生长环线。鳞片上具有明显的“切割”年轮特征;脊椎骨、鳃盖骨上具有明带与暗带(线)形成的年龄特征。(2)布氏哲罗鲑在4龄内,体长在年龄上的回归方程为L=189.9468t+26.7934(r=0.991,df=35);体重年龄的回归方程为W=6.2451.e~(21219t)(r=0.978,df=35);鳞片半径与年龄的回归方程为R=0.7425t—0.1596(r=0.980,df=35);体重和体长的回归方程为W=6.7717357×10~(-6)L~(3.0740)(r=0.999,df=35);体长与鳞片半径的回归方程为L=251.0540R+71.2288(r=0.991,df=35)。(3)布氏哲罗鲑在4龄内,体长平均年增长为189.95mm;并随年龄增大而下降;生长常数、生长指标、肥满度系数等随年龄增大而增大。     

鱼在腌制过程中水份活度和有关参数的变化关系

本文研究了腌制鱼的水分活度(Aw值)变化及其与其他有关参数的关系。以鲳鱼作为试验原料,用混合腌渍法对鱼品进行不同时间的腌制,然后观察鱼体中水分活度、盐分含量和水分含量的变化情况,并进一步探索这些参数之间相互的变化关系。实验结果表明,鱼体中水分活度和水分含量的降低,盐分的增加均在开始腌制至18小时时为最快;18小时后变化缓慢;34小时后基本趋向平衡。实验表明,水分活度,盐分含量与水分含量之间存在简单的线性关系,因此在腌制过程中,测定出水分和盐分含量就可以计算出水分活度Aw值,从而达到控制鱼品质量的目的。此方法在提高鱼品的保藏效果上具有一定的实用价值。