杂交鲌"先锋1号"肌肉营养成分分析及品质评价

为探明杂交鲌“先锋1号”与其母本翘嘴鲌(Erythroculter ilishaeformis)(♀)和父本黑尾近红鲌(Ancherythroculter nigrocauda)(♂)的营养品质差异,对三种鲌肌肉营养品质进行了测定和评价。结果显示:杂交鲌水分含量显著高于父本,粗脂肪含量显著低于父本,灰分含量显著低于母本。杂交鲌肌肉的胱氨酸(Cys)含量显著高于母本,必需氨基酸指数(EAAI)高于父本。杂交鲌肌肉中十五碳烷酸(C15∶0)、α-亚麻酸(C18∶3)的相对含量显著高于翘嘴鲌和黑尾近红鲌。杂交鲌肌肉硬度显著高于母本,肌肉弹性显著低于父本;铁含量与父本无显著差异,但显著高于母本。结果表明,杂交鲌“先锋1号”肌肉营养成分兼具双亲的优良性状,表现出一定的杂交优势,是一种优质的营养资源。     

松花江鲤鱼肌肉肌苷酸含量和鱼肉保鲜时间的研究

纸层析法对松花江鲤鱼肌肉肌苷酸含量和鱼肉保鲜时间作了研究，结果表明：室温２０℃下，鲤鱼肌肉存放３小时左右，肌苷酸含量达到了最高值为６．３２６±０．１２μｍｏｌ／ｇ，保鲜时间为９小时。冷冻－１８℃下，鲤鱼肌肉存放１０天，肌苷酸含量达到了峰值为５．９３１±０．１３μｍｏｌ／ｇ，保鲜时间为２０天。     

Effects of Yuzu (Citrus junos) Peel from Waste as an Aquaculture Feed Supplement on Growth,Environmental Load,and Dark Muscle Discoloration in Yellowtail Seriola quinqueradiata

Beneficial utilization of yuzu (Citrus junos) peel was investigated to improve the commercial value of cultured yellowtail fish. The antioxidant effects of grated yuzu peel from pomace (yuzu paste) on prevention of dark muscle discoloration during storage in sliced yellowtail fish were tested. Four diets were prepared, containing 0, 10, 50, and 100 g yuzu paste in a 1,450-g diet (wet basis). Fish were fed one of the four diets for 10 weeks. Growth performance was not significantly different among the dietary groups, but fish fed a diet containing 100-g yuzu paste showed the least average body weight and a significant increase in fecal amount and fat levels in the feces, which suggest low digestibility and low absorption. Dark muscle discoloration was significantly reduced in all yuzu dietary groups compared to the control group during storage at 4°C. The optimal supplementation of yuzu paste in the fish diet is very effective at maintaining fish flesh freshness as a finishing diet without causing additional phosphorus or nitrogen pollution of the sea and inhibiting fish growth. This study provides a new way to utilize waste yuzu peel, which also helps reduce waste from yuzu processing.     

赛里木湖高白鲑和凹目白鲑肌肉、卵的营养分析评价

2003年作对赛里木湖高白鲑和凹日白鲑肌肉、卵的营养成分进行测定。结果表明：高白鲑和凹目白鲑肌肉蛋白质含量分别为18．83％和19．78％(鲜重)；肌肉脂肪含量分别为13．75％和10．40％；氨基酸总量分别为17．48％和17．71％，其中必需氨基酸含量分别为9．16％和9．24％，占氨基酸总量的52．40％和52．17％；高度不饱和脂肪酸占脂肪酸总量的16．08％和22．73％。高白鲑和凹目白鲑卵的蛋白质含量分别为24．16％和24．48％。     

Artificially induced tetraploid masu salmon have the ability to form primordial germ cells

Diploid gametes generated with tetraploid animals are a stepping stone to improving chromosome manipulation techniques. However, artificially induced tetraploid individuals generally die soon after hatching. Diploid gametes could be induced by in vivo cultures of tetraploid primordial germ cells (PGCs) through germ-line chimera. In the present study, characteristics of PGCs were studied in inviable tetraploid masu salmon, Oncorhynchus masou. Histological observation of tetraploid embryos revealed that the same or smaller numbers of PGCs were observed and they migrate into the genital ridges as did diploid PGCs during gonadogenesis. By whole-mount in situ hybridization using vasa messenger RNA (mRNA), 4–35 vasa-positive signals were detected in a pair of genital ridges of tetraploids. By cytological observation of genital ridge cell suspensions, several large round cells were observed, some of which extended pseudopodia. They also contained large nuclei and round granules in their cytoplasm, characteristics of PGCs. As the results suggest that inviable artificial tetraploids have PGCs, we expect to achieve diploid gamete production through surrogate propagation and tetraploid fish production.     

Sodium alginate supplementation modulates gut microbiota,health parameters,growth performance and growth‐related gene expression in Malaysian Mahseer Tor tambroides

This study investigated the effects of sodium alginate supplementation on gut microbiota composition, health parameters, growth performances and growth‐related gene expression of Malaysian mahseer. Five test diets were formulated by supplementing 0%, 0.1%, 0.2%, 0.4% and 0.8% sodium alginate. Triplicate groups of juvenile Tor tambroides (2.19 ± 0.05 g) were stocked in 15 aquaria (20 individuals per aquarium) and fed at 3.0% body weight per day for 60 days. PCoA and UPGMA analysis showed that gut bacterial community were more convergence in higher sodium alginate‐supplemented diets. The percentage of Porphyromonadaceae, Bacteroides, Plesiomonas and Shewanella were substantially higher and Aeromonas, Entomoplasmatales and Prevotellaceae were drastically lower in higher sodium alginate (0.2%–0.8%) diets. Sodium alginate supplementation (≥0.2%) significantly improved the haematocrit value and respiratory burst activity of T. tambroides. Growth performances and feed utilization were significantly higher in 0.2%–0.4% sodium alginate‐supplemented diets. The increased growth rate of T. tambroides was governed by both hyperplastic and hypertrophic muscle growth. Real‐time PCR data demonstrated that most of the growth‐related genes were significantly upregulated in 0.2%–0.4% sodium alginate‐supplemented diet. Finally, it can be concluded that sodium alginate should be supplemented at 2 g/kg in practical fish feed formulation.     

湘华鲮肌肉营养成分分析与品质评价

利用常规方法对湘华鲮(Sinilabeo decorus tungting)的肌肉营养成分进行了测定。结果表明:湘华鲮(鲜样)中粗蛋白、粗脂肪、水分和粗灰分的含量分别为20.03%、0.80%、77.43%和1.31%。肌肉中含有17种氨基酸,占肌肉总量的76.52%(干样),其中7种人体必需氨基酸占肌肉总量的36.22%,占氨基酸总量的47.30%。4种鲜味氨基酸占肌肉总量的25.97%(干样),另外还富含钙、铁、锌等矿物质,微量元素比值合理。结果表明湘华鲮有较高的食用与营养价值。     

Study on the glass transition for several processed fish muscles and its protein fractions using differential scanning calorimetry

ABSTRACT:   The glass transition behavior of processed fish muscles (bonito, tuna, mackerel, sea bream, cod) and its muscle protein fractions (sarcoplasmic and myofibrillar proteins) were studied using differential scanning calorimetry. Each dried processed fish muscle and the extracted protein fractions showed clear glass transition phenomenon. The T _g values of muscles and myofibrillar proteins from red muscle fishes tended to be lower than those from white muscle fishes though there was no difference on T _g of sarcoplasmic proteins. The T _g value of whole muscle was considerably lower than that of extracted protein fractions because of the plasticizing effects of low molecular weight materials contained in the muscle.     

驼背鲈血细胞的超微结构

利用电镜技术对驼背鲈（Cromileptes altivelis）外周血细胞的超微结构进行了研究。结果表明,电镜下可区分6种类型的细胞：红细胞、粒细胞、单核细胞、淋巴细胞、血栓细胞和浆细胞。红细胞呈圆形或椭圆形,可见线粒体、少数囊泡;根据细胞中的颗粒形态大小和细胞核的形态,可将粒细胞分为4种类型：I型粒细胞、II型粒细胞、III型粒细胞和IV型粒细胞。单核细胞圆形,表面较平整,偶有伪足伸出,空泡多见;淋巴细胞的胞质少,仅在细胞核边缘处形成薄薄的一层,细胞器少;血栓细胞异染色质丰富,沿核膜呈带状分布,胞质中有较多大小不等的空泡和少量的线粒体;浆细胞中粗面内质网成层分布包绕在核周围。此外可见到嗜曙红细胞吞噬红细胞、血栓细胞成群聚集分布的现象。