西藏哲古措2种土著鱼类消化道寄生蠕虫的群落结构及感染状况

为了解西藏哲古措土著鱼类消化道寄生蠕虫的群落结构及季节动态，于2018年9月（秋季）和12月（冬季）、2019年3月（春季）和6月（夏季）对哲古措进行了4个季节的采样调查。共采集到2种土著鱼类，分别为高原裸鲤（Gymnocypris waddellii）和异尾高原鳅（Triplophysa stewartii），与原来的记录不同。在高原裸鲤的消化道中采集到了5种寄生蠕虫，分别为聂氏拟短结绦虫（Parabreviscolex niepini）、新棘吻虫未定种（Neoechinorhynchus sp.）、异肉吸虫未定种（Allocreadium sp.）、对盲囊线虫未定种线虫（Contracaecum sp.）和束首线虫未定种（Streptocara sp.），并对形态特征进行了描述。本研究发现，哲古措土著鱼类消化道寄生蠕虫的物种组成具有一定地域性，大部分为广布性寄生虫，鸟类在其传播过程中起到了重要作用。经过分析，高原裸鲤消化道寄生蠕虫群落的Shannon-Wiener多样性指数为0.70~1.27，显示了较高的群落多样性，Berger-Parker优势度指数为0.38~0.76，优势群为线虫。线虫表现出一定的季节消长规律：秋季为周年最高，冬季下降，春季上升，夏季降至最低，推测与水温、中间宿主的种群数量、线虫的生命周期和鱼类宿主繁殖期的行为等有关。复殖吸虫、绦虫和棘头虫四季的感染率均在10%以内浮动，平均丰度也较低。异尾高原鳅的消化道中未发现任何寄生蠕虫，推测与宿主肠道空间大小、摄食量和分布空间的差异有关。本研究通过对西藏湖泊土著鱼类寄生蠕虫的调查与分析，旨在为深入了解西藏寄生虫的组成特点、研究青藏高原隆升对寄生虫与鱼类宿主协同进化提供基础理论依据。     

叶尔羌高原鳅形态性状与体重的通径分析及曲线拟合

本研究基于叶尔羌高原鳅(Triplophysa yarkandensis)体重(Y)及形态变量(X₁~X₉) 10 个性状, 运用相关性分析、 回归分析、通径分析等开展各形态性状与体重间的相关性及各形态性状间的相关性研究, 量化计算各形态性状对体重的影响, 确定影响其体重的主要形态性状, 进一步确定了 3 个主要形态性状与体重的最佳拟合模型。研究发现, 叶尔羌高原鳅各形态性状与体重之间呈极显著正相关(P＜0.01), 与体重(Y)相关性最大的是体长(X₂), 相关系数为 0.960; 尾柄长(X₅)、眼径(X₇)与眼间距(X₈)之间无显著相关性(P＞0.05), 其他形态性状之间均呈显著正相关(P＜0.05)。 通径分析量化形态性状对体重(Y)的作用, 直接影响最大的是头长(X₄)(0.470), 体长(X₂)通过头长(X₄)对体重的间接作用最大(0.447); 通过回归分析并计算决定系数发现, 头长(X₄)对体重的直接决定系数最大(0.221), 体长(X₂)和头长(X₄)的共同决定系数最大(0.341)。3 个形态性状与体重的多元回归方程为 Y=–2.8+2.94X₂+0.764X₄+0.906X₅ (R² =0.958)。 3 个主要形态性状与体重的最佳拟合模型: 体长(X₂)与体重(Y)的最佳拟合模型为指数函数方程 Y=2.739e^0.158X₂ (R² =0.936); 头长(X₄)与体重的最佳拟合模型为幂函数方程 Y=4.946X₄ ^1.100 (R² =0.931); 尾柄长(X₅)与体重的最佳拟合模型为对数函数方程 Y=9.582+8.876lnX₅ (R² =0.807)。研究结果表明, 叶尔羌高原鳅在选育时, 应以体长(X₂)和头长(X₄)为主要选择性状, 同时辅以尾柄长(X₅)。     

基于ELEFANI和LBB的竺山湖贝氏䱗资源状况评估

为获得竺山湖水域贝氏?(Hemiculter bleekeri)的种群参数, 评价其资源利用状况, 根据 2019 年 10 月至 2020 年 9 月在竺山湖水域收集的贝氏基础生物学数据 ? , 利用基于长度频率数据的 ELEFAN I (electronic length frequency analysis ) Ⅰ 和贝叶斯评估方法(length-based Bayesian biomass, LBB)估算其种群参数。结果显示, 贝氏体长 ? 范围为 44.17~181.87 mm, 体重范围为 0.88~70.30 g; 体长(L, mm)与体重(W, g)关系式为 W=9.0×10^?5L^3.0707 (R2 = 0.8775, n=805); 体长和体重的生长方程分别为 L_t=194.25×[1?e^{?0.36(t+0.46)}], W_t=95.74×[1?e^{?0.36 (t+0.46)}] ^3.0707。运用 ELEFAN I 方法估算的相对自然死亡系数 M/K=2.28, 相对捕捞死亡系数 F/K=4.50, 相对总死亡系数 Z/K=6.78, 开发率 E=0.66。LBB 估算的相对死亡系数 M/K、F/K、Z/K 和开发率 E 分别为 1.88、5.78、7.64 和 0.76。两种方法估算的种群参数基本一致。本研究揭示了竺山湖贝氏的种群生长特性及资源利用状况 ? , 可为太湖的渔业资源科学管理提供依据。     

利用鳍条研究北太平洋长鳍金枪鱼的年龄与生长

根据2013—2014年在大连远洋渔业金枪鱼钓有限公司的超低温金枪钓渔船“天祥”16号船上采集的258个鳍条样品为基础(从845尾长鳍金枪鱼样本中随机选取了258个鳍条样本)，研究了北太平洋长鳍金枪鱼的年龄和生长情况。研究首次采用了3个不同的切割位置(鳍条全长的10%、20%、50%标记段)对鳍条截面进行处理，利用线性函数、指数函数和幂函数分别拟合长鳍金枪鱼叉长和鳍条截面半径之间的关系，采用赤池信息准则(AIC)来获得最优化的函数，并计算其逆算叉长，最后得到北太平洋长鳍金枪鱼的生长方程、生长拐点以及生长率和生长指标。研究表明，北太平洋长鳍金枪鱼的主要年龄段集中在4~6龄，不分雌雄的生长方程为L_t=112.231×[1-e^{-0.277 132×(t+1.435)}]，拐点年龄为2.53，生长率和生长指标随着年龄的增长呈递减的趋势，且年龄越大变化越小。本研究可为北太平洋长鳍金枪鱼的资源状况评估及渔业可持续发展提供生物学信息。     

岱衢洋和官井洋大黄鱼自交与杂交子代生长性能及杂交优势分析

2007年3月至2008年8月对象山港海区网箱养殖的岱衢洋、官井洋大黄鱼自交以及正反向杂交子代进行生长特性观察。结果表明:整个实验过程(0~526 d),官井洋大黄鱼自交子代(GG)和反交子代(GD)(官井洋♀×岱衢洋♂)大黄鱼较岱衢洋自交子代(DD)和正交子代(DG)(岱衢洋♀×官井洋♂)大黄鱼生长快,到526 d实验结束时,GG和GD体重分别达到330.514 g和336.694 g,而DD和DG则仅为278.975 g和243.297 g。对其各阶段生长速度分析,发现虽然一龄DD生长较慢,但过冬后DD生长明显加快,体长增长速度超过其他各群子代,体重增长也达到GG和GD增长水平,即有后期增长潜能。对比各群子代肥满度发现,526 d时,DD肥满度最低(1.675),GD肥满度(1.779)虽高于DD,但显著小于GG(1.933)。鉴于GD生长速度高于DD,与GG相当,而体型又优于GG,认为GD具有较大的经济养殖和优良品种选育的潜力。拟合各阶段体长体重数据,得出各群体生长曲线公式如下,DD:W=0.0206L^2.9427, R²=0.9949;GG:W=0.0139L^3.0994,R²=0.9785;DG:W=0.0229L^2.9136,R²=0.9905;GD:W=0.0177L^3.0079,R²=0.9949,拟合度较好,可通过体长估算体重,应用于实际生产。     

低盐度养殖的凡纳滨对虾体长和体重的增长规律

通过池塘陆基围隔实验，研究了凡纳滨对虾在最适水温、溶氧、pH及低盐度(2～6)养殖环境的生长特性及规律。实验结果，低盐度养殖健康对虾体长和体重平均生长率分别为1.398 mm·d^-1和0.169 g·d^-1，对虾前期体长呈线性生长，中后期体重呈加速增长。非线性拟合结果，对虾体长生长为二次曲线，符合Quadratic模型，体重增长为S型曲线，符合Boltzmann模型，生长观测值与模型拟合相关系数R²均达到0.99；凡纳滨对虾低盐度养殖典型体长和体重生长模型为L=7.843+2.297t-0.0105t²和W=16.541+(-0.621-16.541)/(1+e^{(t-54.809)/15.456})。低盐度养殖，对虾体长与体重呈立方关系，符合幂指数模型W=aL^b，a值范围4.9～9.0×10^-6，b值范围2.9495～3.0716，相关系数R²在0.99以上，典型幂指数模型为W=4.9×10^-6L^3.0716。     

中东太平洋长鳍真鲨年龄与生长

长鳍真鲨(Carcharhinus longimanus)为大洋性中上层鲨类, 由于其全球资源被过度捕捞, 已被列入 IUCN 濒危物种名录。开展长鳍真鲨年龄鉴定与生长规律的研究, 可为其资源恢复及物种保护提供理论依据。本研究以中东太平洋金枪鱼延绳钓兼捕渔获物中的 87 尾长鳍真鲨为样本(雄性 43 尾, 雌性 44 尾), 结合脊椎骨年龄鉴定结果和生物学数据分析该海域长鳍真鲨年龄及生长规律。赤池信息量准则(AICC)分析表明, 长鳍真鲨脊椎骨半径(r)与全长(L)的关系符合线性回归模型。von Bertalanffy (VB)生长模型为总体观测数据最适模型, 表达式为 L_t=398[1-e^{-0.04(t+6.81)}] , 结合反向逆推个体早期全长数据, 雌性逆推全长的最适模型为 VB 模型 L_{t female} =330.8[1-e^{–0.05( t+5.84)} ] , 雄性为 Gompertz 模型L_{t male} = 363e^{–1.49e( -0.08t )} 雌、雄个体 50%性成熟年龄 t₅₀ 分别为(8.8±1.2)龄和(8.6±1.2)龄, 50%性成熟全长 L₅₀ 分别为(191±9.1) cm 和(173±12.9) cm。     

北极茴鱼形态性状对体重影响效果分析

为探明北极茴鱼(Thymallus arcticus)形态性状与体重的关系, 以 1⁺ ~3⁺ 龄北极茴鱼为研究对象, 测定了体重(Y) 和体厚(X₁)、眼间距(X₂)、体长(X₃)、体高(X₄)、头长(X₅)、眼径(X₆)、吻长(X₇)、尾柄长(X₈)、尾柄高(X₉)等 9 个形态性状, 利用相关分析、通径分析和多元回归分析等方法, 筛选出影响北极茴鱼体重的主要形态性状, 并建立回归方程。结果显示: (1) 不同年龄阶段, 与北极茴鱼体重显著相关(P＜0.05)的形态性状种类不同, 且数量也随着年龄的增加而降低。(2) 通径分析在 1⁺ ~3⁺ 龄北极茴鱼中分别保留了 4、4 和 2 个形态性状, 1⁺ 龄北极茴鱼中体长(X3)的直接作用最大(0.345), 尾柄高(X9)的间接作用最大(0.745); 2⁺ 龄北极茴鱼中体高(X4)的直接作用最大(0.473), 体厚(X1)的间接作用最大(0.378); 3⁺ 龄北极茴鱼中体厚(X₁)的直接作用最大(0.635), 尾柄高(X₉)的间接作用最大(0.344)。(3) 通径分析保留的形态性状对 1⁺ ~3⁺ 龄北极茴鱼体重的总决定系数较高, 分别为 0.943、0.778 和 0.997。(4) 多元回归分析拟合出 1+ 龄北极茴鱼形态性状(Xi)与体重(Y)回归方程为 Y=?90.510+15.345X₁+3.638X₃+10.473X₄+16.884X₉, 2+ 龄北极茴鱼形态性状(Xi)与体重(Y)回归方程为 Y=?142.449+29.023X₁+81.082X₂+27.126X₄?47.376X₇, 3⁺ 龄北极茴鱼形态性状(Xi)与体重(Y)回归方程为 Y=?228.922+75.063X₁+107.864X₉。本研究丰富了北极茴鱼基础生物学数据, 同时为将来人工养殖利用过程中北极茴鱼的选择育种提供待选形态性状。     

环境因子对鼠尾藻幼苗叶绿素荧光参数的影响

为了揭示鼠尾藻幼苗的生态适应性,研究了温度(5~34 ℃)、盐度(10~50)和营养盐等环境因子对鼠尾藻幼苗叶绿素荧光参数的影响。结果表明,(1) 氮浓度高于8 mg/L或磷浓度高于1.2 mg/L,或温度高于28 ℃,对鼠尾藻幼苗的光合作用均有显著影响(P<0.05);(2) 短时间的5~15 ℃的低温胁迫或10~50盐度胁迫6 h对鼠尾藻幼苗的F_v/F_m值影响不明显;(3) 氮、磷浓度分别为2~4 mg/L和0.2~0.8 mg/L,且NH⁺₄-N∶NO^-₃-N的比值为1~3时,较利于鼠尾藻幼苗光合作用的进行。     

星康吉鳗形态性状与体重的通径分析及生长曲线拟合

为探明星康吉鳗（Conger myriaster）形态性状和体重的关系，测定了体重（Y）及全长（X₁）、肛长（X₂）、尾长（X₃）、头长（X₄）、吻长（X₅）、眼径（X₆）、眼后头长（X₇）、背鳍前长（X₈）、躯干长（X₉）、头宽（X₁₀）、眼间距（X₁₁）等11个形态性状，通过相关分析、通径分析、回归分析等方法研究了形态性状对体重的影响；通过曲线拟合获得4个形态性状与体重的最佳拟合模型。结果表明，星康吉鳗各形态性状之间以及形态性状与体重之间均呈极显著正相关关系（P< 0.01）。相关分析发现肛长（X₂）与体重的相关系数最大（0.970）；通径分析发现肛长（X₂）对体重的直接作用最大（0.450），头宽（X₁₀）通过肛长（X₂）对体重的间接作用最大（0.431）；决定系数分析发现，肛长（X₂）对体重的直接决定系数最大（0.203），肛长（X₂）和头宽（X₁₀）的共同决定系数最大（0.172）。形态性状（X）与体重（Y）的多元回归方程为Y=-113.859+6.481X₂+49.213X₆+11.514X₇+20.145X₁₀（R²=0.954）。星康吉鳗肛长（X₂）、眼后头长（X₇）、头宽（X₁₀）与体重的最佳拟合模型为指数函数，模型方程分别为Y=1.466e^0.287X、Y=1.435e^1.328X、Y=1.970e^1.974X，眼径（X₆）与体重的最佳拟合模型为线性，方程为Y=-77.460+222.093X。结论认为，在星康吉鳗选育时，应以肛长（X₂）和头宽（X₁₀）为主要选择性状，以眼径（X₆）和眼后头长（X₇）为辅助选择性状。     

Atlantic Fisheries Technological Conference,Moncton, NB,August 21, 1995

No abstract available for this article.     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

Age,growth, maturity and the overfishing of the iconic sciaenid,Argyrosomus japonicus,in south-eastern,Australia

Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L₅₀ of 68 cm, whereas males matured at 2–3 years of age with a L₅₀ of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.     

Surface disinfection of Pacific threadfin, Polydactylus sexfilis, and amberjack, Seriola rivoliana, eggs

The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L⁻¹ H₂O₂ for 5 min. Exposure to 34 230 mg L⁻¹ H₂O₂ for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L⁻¹ PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>10⁴ cfu egg⁻¹), hydrogen peroxide concentrations of at least 11 340 mg L⁻¹, or PVP‐I concentrations higher than 500 mg L⁻¹ for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L⁻¹) concentrations of H₂O₂ was sufficient to result in high apparent levels of surface sterility (<1 cfu egg⁻¹).     

Effects of Mosquitofish,Gambusia affinis,on Channel Catfish,Ictalurus puncatatus,Production Ponds

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.     

Compositional differences,antioxidant activity,angiotensin-converting enzyme inhibition,and sensory characteristics of kamaboko fermented in wheat,rice, brown rice,and soybean koji

Fisheries Science - Fermentation of kamaboko in koji with wheat (KW), rice (KR), brown rice (KB), or soybean (KS) was performed by simulation of tofuyo processing. Moisture and protein content...     

Sperm Motilities in Waigieu Seaperch,Psammoperca waigiensis: Effects of Various Dilutions,pH, Temperature,Osmolality, and Cations

The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl₂ (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl₂ (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch.