池养尖吻鲈人工繁殖的研究

尖吻鲈Lates calcarifer(Bloch)，又名盲鳍，其生长迅速，肉味鲜美，在东南亚、我国广东省、香港和台湾沿海地区均有养殖。但野生种苗不足成为发展成鱼养殖的障碍。因此，各国致力于尖吻鲈人工繁殖的研究，自1971年泰国在自然产卵场捕获成熟亲鱼进行人工繁殖首获成功以来，东南亚各国，如菲律宾、马来西亚、     

尖吻鲈Lates calcarifer（Bloch）人工繁殖技术现状及其发展前景

尖吻鲈是咸淡水养殖的主要经济鱼类。最近几年来,泰国、新加坡、马来西亚和菲律宾等国家和地区对尖吻鲈养殖已引起极大的兴趣,已深入开展尖吻鲈养殖生物学和繁殖机制的研究。本文着重概述东南亚海洋渔业开发中心研究尖吻鲈Lates calcarifer(Bloch)人工繁殖技术现状及其发展前景。     

池养尖吻鲈和花鲈的生长特性

尖吻鲈（Ｌａｔｅｓｃａｌｃａｒｉｆｅｒ）、花鲈（Ｌａｔｅｏｌａｂｒａｘｊａｐｏｎｉｃｕｓ）为河口性鱼类,可作为池塘养殖的对象。尖吻鲈的适宜生长水温为２５℃～３４℃,快速生长年龄在Ⅰ～Ⅱ龄;花鲈在珠江口地区一年四季均能生长,快速生长年龄在Ⅲ～Ⅳ龄。应用ＶｏｎＢｅｒｔａｌａｎｆｙ方程求得它们在人工饲养条件下体长、体重生长方程：尖吻鲈Ｌｔ＝７０６．５５５３［１－ｅ－０．５１２８（ｔ＋０．２０３２）］,Ｗｔ＝６５５４．４６４９［１－ｅ－０．５１２８（ｔ＋０．２０３２）］３．０３３５;花鲈Ｌｔ＝８８７．４９５８［１－ｅ－０．４０２５（ｔ＋０．０２０９）］,Ｗｔ＝１０８８２．１８８４［１－ｅ－０．４０２５（ｔ＋０．０２０９）］３．１４２７。它们的体重生长拐点分别位于１．９６和２．８２龄处。商品鱼的合理起捕时间应选在生长转折点。参照生物学指标,珠江口地区池养尖吻鲈、花鲈的上市商品鱼应为Ⅰ～Ⅱ龄和Ⅲ～Ⅳ龄,这不仅符合经济原则,也适应当地的消费习惯。     

珠江口沿岸池养尖吻鲈、花鲈的生长特性研究

尖吻鲈(Lates calcarifer Block)分布于泰国、马来西亚、新加坡、印尼、菲律宾以及我国大陆和台湾，是亚洲和太平洋热带、亚热带地区重要经济鱼类。花鲈Latcolabrax japonicus (Cuvier et valencinnes)分布于中国、日本和朝鲜，为我国沿海及河口的名贵经济鱼类。     

尖吻鲈的人工繁殖及种苗培育

尖吻鲈Lates Calcarifey(Bloch)，俗称盲鳕，是东南亚和太平洋热带及亚热带地区的一种重要经济鱼类。其生长迅速，肉味鲜美。目前进行养殖的国家有泰国、印尼、马来西亚、新加坡、菲律宾和我国等，早在80年代，其养殖年产量已近2000吨。东南亚的养殖方式主要是网箱养殖和鱼媪养殖；我国以网箱养殖为主，近几年来发展鱼塘养殖。     

池养尖吻鲈和花鲈的生长特性

尖吻Ｌｕ（Ｌａｔｅｓｃｌａｃａｒｉｆｅｒ）花Ｌｕ（Ｌａｔｅｏｌａｂｒａｘｊａｐｏｎｉｃｕｓ）为河口性鱼类,可作为池塘养殖的对象,尖吻Ｌｕ的适宜生长水温为２５℃～３４℃,快速生长年龄在Ⅰ～Ⅱ龄;花Ｌｕ在珠江口地区一年四季均能生长,快速生长年龄在Ⅲ～Ⅳ龄,应用ＶｏｎＢｅｒｔａｌａｎｆｆｙ方程求得它们在人工饲养条件下体长,体重生长方程,尖吻ＬｕＬｔ＝７０６．５５５３（１－ｅ＾－０．５１２８（ｔ＋０．２０     

世界尖吻鲈养殖及市场

<正> 尖吻鲈(Lates calcarifer)在各国池塘和网箱中广泛养殖。据东南亚渔业发展中心(SEAFDEC)报道,池塘养殖尖吻鲈,当年可收回74％的投资;网箱养殖尖吻鲈,1.4年可收回成本。现将尖吻鲈繁殖、养殖以及国外市场介绍如下。     

江黄颡鱼人工繁殖的初步研究

对江黄颡鱼（Pseudobagrus uachelli Richardson)的人工繁殖进行了初步试验，先用LRH-A2预备针催熟，再用1mgPG 2.5mgDOM 3.5μgLRH-A2混合催产，水温24-27℃下，效应时间为20-24h，产卵率可达97%，采用等渗液稀释磨碎的精巢，经人工授精，受精率达70%，采用塑料网片粘卵，在卵化环道内孵化，孵化率达94%，此外，对江黄颡自然繁殖的生态条件进行了探讨。     

硬壳蛤土池人工育苗技术

本试验对硬壳蛤（Mercenaria mercenaria Linnaeus）进行规模化土池人工育苗,包括亲贝培育、苗池清整、基础饵料培养、人工催产、浮游幼虫及稚幼贝培育、水质监测和敌害防除等。硬壳蛤土池育苗面积60亩,经过近7个月的人工培育,共培育苗种8.25亿粒（平均规格2861粒/kg）,每亩产蛤苗1375.68万粒,亩利润20675元。     

Growth trials for polyculture of hatchery-reared juvenile spotted babylon (Babylonia areolata) and sea bass (Lates calcarifer) in a flow-through sea water system

Juvenile spotted babylon (Babylonia areolata) and sea bass (Lates calcarifer) were cultured in 11.5‐m³ indoor rearing tanks supplied with flow‐through of ambient natural sea water over a 120‐day experiment. Each species, stocked at the following densities for the following treatments, was tested with three replicates per treatment: 5000 B. areolata per tank (Treatment 1); 200 L. calcarifer per tank (Treatment 2); and 5000 B. areolata plus 200 L. calcarifer per tank (Treatment 3),. The average growth (length and weight), feed conversion ratio and total production of spotted babylon and sea bass from Treatment 3 were not significantly different from those of Treatment 1 and 2 (P > 0.05). Average survival rates for both spotted babylon and sea bass exceeded 95% for all treatments.     

Genetic variation of Lates calcarifer in Peninsular Malaysia based on the cytochrome b gene

A 312 bp segment of the mitochondrial cytochrome b gene was sequenced from 132 sea bass Lates calcarifer individuals from nine populations across Peninsular Malaysia. Phylogenetic analysis and analysis of molecular variance within and among populations showed no significant geographical structuring. Several populations formed discrete units while others were of mixed populations. The former group suggests a low gene flow among some populations while the latter suggests that widespread translocations have impacted the other wild and cultured local populations. The data from this study have important implications for fishery management, conservation of sea bass stocks and translocation policy for aquaculture and stock enhancement in Peninsular Malaysia.     

尖吻鲈幼鱼运输密度和时长对运输水质及其复苏率和抗氧化能力的影响

该试验采用塑料袋密闭充氧运输方式,探讨3种运输密度(D1=14 kg·m-3、D2=21 kg·m-3、D3=28 kg·m-3)下模拟运输24 h和运输密度7 kg·m-3下模拟6个不同运输时长(T1=4 h、T2=8 h、T3=12 h、T4=16 h、T5=20 h、T6=24 h)对运输水质、尖吻鲈(Lates...     

滇池金线鲃全人工繁殖研究

用人绒毛膜促性腺激素(HCG)、促黄体素释放激素类似物(LRH—A2 )、马来酸地欧酮(DOM)组成的混合催产剂对滇池金线鲃催产获得成功,用人绒毛膜促性腺激素、鲤鱼脑垂体和人绒毛膜促性腺激素组合的催产失败。采取两次注射催产效果明显,第一次用LRH-A2 2μg /Kg催熟,第二次用LRH-A2 8μg /Kg + DOM 3mg/Kg ＋HCG1000IU/Kg催产,效果较好;采取遮光孵化,孵化率明显提高。     

A quantitative determination of deformities in barramundi (Lates calcarifer; Bloch) fed a vitamin deficient diet

Cultured barramundi, Lates calcarifer, suffer from abnormalities affecting the jaw, opercula and spine. The aim of this study was to quantify for the first time the effects of supplemented dietary vitamin C, vitamin D₃ and ultraviolet (UV) light on the development of jaw, opercula and spinal deformities. Four diets were formulated to contain (i) no vitamin C or vitamin D₃, (ii) only vitamin D₃, (iii) only vitamin C and (iv) both vitamin C and vitamin D₃. In addition, two commercial diets (diets 5 and 6) were also tested. These diets were replicated in the presence, and in the absence, of ultraviolet (UV) light as this may also affect skeletal development. Diets formulated with 170 ± 1 mg kg^?1 and 195 ± 0.5 mg kg^?1 of vitamin C (diets 3 and 4, respectively) and the commercial diets (diets 5 and 6) had significantly lower incidences of spinal deformities (0–2.5%; P < 0.01) and opercula deformities (nil detected). Spinal deformities were ‘broken back’ syndrome, which was found only in the precaudal vertebrae, and lordosis which was only in the caudal vertebrae. UV light and vitamin D₃ did not affect spinal or opercula deformities. There was no change in the occurrence of jaw deformities in vitamin C, vitamin D₃ or UV light treatments.     

Draft genome sequence of scale drop disease virus (SDDV) retrieved from metagenomic investigation of infected barramundi,Lates calcarifer (Bloch, 1790)

Scale drop disease virus (SDDV) is a novel viral pathogen considered to be distributed in farmed barramundi (Lates calcarifer) in South-East Asia. Despite the severity of the disease, only limited genomic information related to SDDV is available. In this study, samples of SDDV-infected fish collected in 2019 were used. The microbiome of brain tissue was investigated using Illumina HiSeq DNA sequencing. Taxonomic analysis showed that SDDV was the main pathogen contained in the affected barramundi. De novo metagenome assembly recovered the SDDV genome, named isolate TH2019, 131 kb in length, and comprised of 135 ORFs. Comparison between this genome and the Singaporean SDDV reference genome revealed that the nucleotide identity within the aligned region was 99.97%. Missense, frameshift, insertion and deletion mutations were identified in 26 ORFs. Deletion of four deduced amino acid sequence in ORF_030L, identical to the SDDV isolate previously identified in Thailand, would be a potential biomarker for future strain classification. Interestingly, the genome of SDDV TH2019 harboured a unique 7,695-bp-long genomic region containing six hypothetical protein-encoded genes. Collectively, this study demonstrated that the SDDV genome can be sequenced directly, although with limited coverage depth, using metagenomic analysis of barramundi sample with severe infection.