白梭吻鲈3个群体的遗传结构比较

为了加强良种选育工作,切实做好亲本遗传管理,防止近交衰退的发生,利用20个微卫星分子标记对白梭吻鲈(Sander lucioperca)新疆野生群体及山东和苏州2个养殖群体的遗传结构进行检测。结果表明,20个微卫星标记中18个有扩增产物,14个呈现多态性;每个位点的等位基因数为2~6个,平均等位基因数为3.6个,3个群体的平均等位基因数为2.57~3.36,平均观测杂合度为0.5085~0.5621,平均多态性信息含量为0.3931~0.4764,表明3个白梭吻鲈群体的遗传多样性处于中等偏低水平,遗传多样性大小为:新疆群体苏州群体山东群体。群体的Fst为0.1798,表明群体间有一定的遗传分化。在白梭吻鲈人工繁殖与养殖过程中,必须加强亲本遗传结构监测并维持一定数量的亲本规模,以利于其产业的持续发展。     

热胁迫对白梭吻鲈鳃组织结构及抗氧化指标的影响

温度是导致鱼类生理变化的最重要的环境因素之一。热应激导致氧化应激,破坏抗氧化防御系统,并导致脂质和组织病理学的损害。白梭吻鲈(Sander lucioperca)属于亚冷水性鱼类,最适生长水温20～24℃。近年来,由于夏季气温极高,中国池塘出现了大量的白梭吻鲈死亡,白梭吻鲈的水产养殖业一直面临着高温的严峻挑战。鱼鳃参与鱼类许多重要功能,如呼吸,渗透调节和排泄,与外部环境保持密切接触,对水质变化特别敏感。为探究热胁迫对白梭吻鲈鳃组织结构及抗氧化指标的影响,将100尾鱼暴露于28℃,31℃,34℃,36℃热应激2h,以23℃作为对照组。收集鳃用于石蜡切片制备,并将苏木精伊红（HE）染色用于一般组织学观察。测定超氧化歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPX）活性和丙二醛（MDA）等抗氧化指标。结果显示,28 ℃组鳃小片发生充血,31 ℃组部分鳃小片末端卷曲变形、上皮细胞水肿,34 ℃组鳃小片变形加重,且有少量融合,上皮细胞水肿加重、明显隆起,鳃小片之间粘液细胞肥大、增生,36 ℃组相邻鳃小片大量融合且严重变形,卷曲混乱排列,大量上皮细胞坏死、脱落,鳃丝粘液细胞增生、肥大;随着胁迫温度升高,鳃中SOD、CAT、GPX、MDA均整体呈现先升高、后降低的变化趋势,且在36℃时显著下降。这表明在热应激后,鱼体内ROS增加,脂质过氧化增加。由于体内产生大量的ROS和H2O2,机体也增加了GPX和CAT的合成。当暴露在36℃时,胁迫强度超过白梭吻鲈的适应能力,抗氧化系统功能无法正常进行。表明热胁迫对白梭吻鲈鳃组织有损伤,且随着热胁迫温度的升高,其鳃受损情况越发严重。     

氯化钠浓度对鲈鲤精子活力的影响

为了解鲈鲤精子的生理特性,研究了不同氯化钠浓度试验条件下鲈鲤精子的活力情况,结果表明:在0％～0.65％氯化钠溶液中鲈鲤精子均能被激活;当氯化钠溶液浓度为0.35％时,鲈鲤精子激烈运动时间和寿命最长,分别为(66.33±7.99)s、(635.66±95.78)s,而且该组的鲈鲤精子的寿命极显著高于其他处理组(P＜0....     

斜带石斑鱼精子超微结构及盐度、温度、pH对精子活力及寿命的影响

选取健康雄性斜带石斑鱼(Epinepheluscoioides)亲鱼进行人工采精,以日立H-600型透射电镜观察精子超微结构,同时设定盐度梯度、温度梯度和pH梯度,观察其对精子活力的影响。超微观察显示,精子头部呈圆形或卵圆形,核膜与质膜间的空间较大;近端中心粒的长轴与尾部约成120°的夹角;基体位于鞭毛顶端,长轴与精子头部细胞核长轴平行;袖套位于核后端,呈筒状,两侧不对称,分布着数量、大小不等的线粒体和囊泡。尾部细长,长26.0～31.5μm,其主要结构是轴丝,轴丝为典型的"9+2"微管结构。活力实验显示,精子活力的最适盐度为27～35,盐度33时精子寿命最长,为27min;最适pH为6.5～8.7,pH8.4时精子运动时间最长,为20min;最适温度为25～31℃,29℃时精子寿命最长,为37min。     

Na+、K+对高白鲑精子活力影响的初步研究

研究了赛里木湖高白鲑精子在盐度为0-0.8%的NaCl和KCl的溶液中的活动情况。结果显示,高白鲑精子在0.5%-0.6%的NaCl溶液中表现出最好的活力;0.1%的K^ 对精子已有明显的抑制作用,并且抑制效应随K^ 含量的升高而增强。     

阳离子、葡萄糖及渗透压对丁Gui精子活力的影响

利用KCl、NaCl、CaCl2和葡萄糖配制成不同渗透压的溶液，丁Gui精子在453．0kPa KCl溶液、226．5kPaNaCl溶液和葡萄糖溶液中的活力最强，寿命最长；566．3kPa已完全抑制精子在这3种溶液中的活动。葡萄糖能有效延长精子寿命，表明丁Gui精子具有利用外源性葡萄糖的能力。56．7kPa CaCl2已构成对精子的抑制作用，并引起精子聚集，而且随Ca2^2 浓度增高，对精子的抑制作用和聚集程度更严重。     

阳离子、葡萄糖及渗透压对丁精子活力的影响

利用KCl、NaCl、CaCl2和葡萄糖配制成不同渗透压的溶液,丁鱼岁精子在453 0kPaKCl溶液、226 5kPaNaCl溶液和葡萄糖溶液中的活力最强,寿命最长;566 3kPa已完全抑制精子在这3种溶液中的活动。葡萄糖能有效延长精子寿命,表明丁鱼岁精子具有利用外源性葡萄糖的能力。56 7kPaCaCl2已构成对精子的抑制作用,并引起精子聚集,而且随Ca2+浓度增高,对精子的抑制作用和聚集程度更严重。     

不同浓度的K~+、Ca~(2+)和葡萄糖对乌原鲤精子活力的影响

通过观察精子的快速运动时间和寿命,研究了不同浓度梯度的K+、Ca2+和葡萄糖溶液对乌原鲤精子活力的影响。结果表明:不同浓度的K+、Ca2+和葡萄糖溶液对乌原鲤精子运动的诱导效果不同。3种溶液最适于乌原鲤精子运动的浓度分别为:K+100 mmol/L;Ca2+37.8 mmol/L;葡萄糖125mmol/L,且在这3种溶液低浓度时精子活力较强,超过一定浓度精子的运动开始被抑制。     

尖吻和钝吻细鳞鱼(Brachymystax Lenok)精子活力的观察

在不同的激活剂中尖吻细鳞鱼的精子激活率,都显著好于钝吻的;在水和BSS溶液中尖吻细鳞鱼的精子寿命显著高于钝吻的（P〉0．05）;用BSS激活的尖吻细鳞鱼精子的强烈运动时间显著长于钝吻的（P〉0．05）。在不同条件下尖吻细鳞鱼精子的保存时间要长于钝吻的。在4℃条件下保存的精液,尖吻的是钝吻的约3倍;室温下（14℃）精液原浆保存,尖吻的是钝吻的近2倍。     

Pikeperch (Sander lucioperca) spermatozoa motility and volume regulation under different osmotic and ionic conditions

Fish Physiology and Biochemistry - Pikeperch (Sander lucioperca) is a highly profitable commercial species whose economic value has greatly increased in the last decade. As in other species, the...     

The effect of K+, Ca2+, and Mg2+ on sperm motility in the perch,Perca fluviatilis

This study investigated the effect of 0.25–5 mM K⁺, Ca²⁺, and Mg²⁺ on sperm motility in the perch, Perca fluviatilis. In 75 mM NaCl, the used motility-activating solution, motility rate, and swimming velocity decreased within the first 4 min after activation, and the rate of locally motile sperm increased. Thereafter, the motility parameters remained constant for periods >20 min. Based on the decrease in sperm motility, two types of semen samples could be distinguished. Semen samples of type I retained a high motility rate of >65 % after 20 min, and the rate of locally motile sperm was <20 %. In semen samples of type II, the motility rate decreased to values <30 % after 20 min, and the rate of locally motile sperm exceeded >50 %. Ca²⁺ and Mg²⁺ concentrations of 0.25–0.5 mM had no effect on the sperm motility parameters 10 s after activation, while 0.25 mM K⁺ increased the swimming velocity. K⁺, Ca²⁺, and Mg²⁺ concentrations ≥1.5 mM had suppressive effects on the sperm motility 10 s after activation. No differences were found between the two semen types. Twenty minutes after activation, type I semen was not affected by the tested cations. On the contrary, 0.25–2.5 mM K⁺, 0.25 mM Mg²⁺, and 0.25–2.5 mM Ca²⁺ significantly increased the sperm motility rate and/or sperm velocity of type II semen. Therefore, supplementation of saline solution with cations might stabilize the motility of perch sperm, which can be a benefit for experimental purposes and for specific handling procedures in aquaculture.     

The role of Ca2+ and Na+ membrane transport in brook trout (Salvelinus fontinalis) spermatozoa motility

The role of environmental ion composition and osmolality in Ca²⁺ signaled activation was assessed in spermatozoa of brook trout Salvelinus fontinalis. Milt from ten mature males was obtained by abdominal massage. Spermatozoa motility was evaluated in 0, 100, and 300 mOsm/kg NaCl or sucrose solutions, buffered by 10 mM Tris–HCl pH 8.5. For investigation of spermatozoa reaction to external Ca²⁺ concentration, 2 mM ethylene glycol tetraacetic acid (EGTA) was added to the activation media as a calcium ions chelator. For investigation of the effect of external Na⁺ concentration in conditions of low external Ca²⁺, 100 µM amiloride was added to the EGTA-containing solutions as a Na⁺ transport blocker. Low motility was observed in sucrose (Na⁺ free) solutions containing 2 mM EGTA but not in Na⁺ solutions containing 2 mM EGTA. Addition of amiloride led to significantly increased motility (P < 0.05) compared with sucrose (Na⁺ free) solutions containing 2 mM EGTA. We conclude that Na⁺ transport in Ca²⁺-free solutions plays a regulatory role in brook trout spermatozoa activation. The influence of competitive Na⁺ and Ca²⁺ transport on the control of spermatozoa activation requires further study with respect to its application for improvement of artificial activation and storage media.     

河蟹和罗氏沼虾幼体对海水中K+、Ca2+、Mg2+的需要量

河蟹(Eriocher sinensis)、罗氏沼虾(Macrobrachiun rosen-bergii)在发育过程中均需蜕壳变态。壳的主要成分为几丁质,其中含有大量的Ca2 。水体中Ca2 的含量高,则甲壳中沉积的Ca2 也高,使甲壳钙化,难以蜕壳;若水中Ca2 的含量过低,甲壳形成困难,影响其正常生理机能,同样会影响生长发育。K 是维持细胞渗透压的离子之一,参与机体的酸碱平衡调节,过高或过低同样会影响虾蟹类的生长发育[1]。所以,水体中的K 和Ca2 的含量必须满足甲壳类生长发育的要求。水体中K 和Ca2 的含量变动很大,育苗前必须对育苗用水进行水质分析,K 和Ca2 的含量过高…     

葡萄糖、丙三醇和盐对厚唇裂腹鱼精子活力的调控研究

为了探究厚唇裂腹鱼(Schizothorax irregularis)精子活力的调控规律,提高受精率和苗种生产效率,文章采用显著性检验和响应面法,研究了葡萄糖、丙三醇和3种盐对厚唇裂腹鱼精子活力的单项调控和复合项调控作用。结果表明,葡萄糖为433.7 kPa时厚唇裂腹鱼精子的快速运动时间(FT)最大(37.00 s),显著高于其他组(P<0.05);丙三醇为506.7 kPa时厚唇裂腹鱼精子的FT最大(32.33 s),与416.3 kPa组无差异,但显著高于其他组(P<0.05);氯化钠为431.4 kPa时厚唇裂腹鱼精子的FT最大(35.00 s),与348.8 kPa组无差异,但显著高于其他组(P<0.05);氯化钾对精子的激活效果不明显,氯化镁则有抑制效果;建立了厚唇裂腹鱼精子FT与葡萄糖、丙三醇和氯化钠的拟合方程,该方程的一次效应、二次效应均极显著(P<0.01),交互效应显著(P<0.05);模型优化配方为氯化钠164.78 kPa、丙三醇216.55 kPa、葡萄糖208.43 kPa,理论FT为68.24 s。运用响应面法优化的激活液配方,能有效提高该鱼的精子活力。     

Temperature dependent growth and yield of pikeperch, Sander lucioperca, in Finnish lakes

Abstract  A non-linear growth model was used to evaluate the effects of temperature and age on annual length increments of pikeperch, Sander lucioperca (L.), in seven lakes in Finland. Length increments were derived by back-calculation using the Fraser–Lee method. Annual length increments increased from age 1 to age 3 and then decreased, while at the same time length increments and air temperature had positive correlation until age 12. Age- and size-structured yield per recruit models were used in two lakes to evaluate the effects of temperature and gillnet mesh size on pikeperch yield. In these two lakes maximum yield could be obtained with 60 and 70 mm (bar length) gill nets. In the second lake, as typically in Finland, 45–50 mm gill nets are the most frequently used. The use of larger mesh size gill nets would increase pikeperch yield from 685 to 1000 g per recruit based on the present mean temperature. In both lakes increase in temperatures would increase yield if mesh size is simultaneously increased. Higher pikeperch yield can be expected in the future because of climate warming.     

Effects of hormonal manipulation on stress responses in male and female broodstocks of pikeperch Sander lucioperca

This study was designed to determine the effects of hormonal manipulation on stress responses in female and male pikeperch. Two-year-old cultured female and male broodstocks with an average weight of 337.4 ± 20.1 (mean ± SE; n = 16) and 318.7 ± 15.1 g (n = 16), respectively, were randomly allocated into four hormonal treatments each containing 4 fish. Two sexual groups of 16 fish for each gender were considered. Sexually mature male and female pikeperch were injected with either physiological saline solution (as control group), common carp pituitary extract (CPE), human chorionic gonadotropin (hCG) and or luteinizing hormone-releasing hormone analog (LHRHa₂). The blood samples were taken before hormonal injection and after ovulation and spermiation. Then the plasma levels of stress indices (cortisol, glucose, and lactate) were determined. The results showed that all CPE-, HCG-, and LHRHa_2- injected males produced sperm. In females treated with CPE and hCG, three of four ovulated, but none of LHRHa_2- and saline-injected fish spawned. Significant changes in cortisol, glucose, and lactate levels were observed among the females injected with different hormones. Plasma cortisol and glucose levels increased significantly in males injected with CPE and females injected with hCG, but no significant change was observed in lactate levels before and after hormonal induction. Comparison of two sexes revealed significant differences in glucose levels for females in some groups before injection, while CPE-injected sexes showed significant changes in cortisol and lactate concentrations. The results indicated that the induction of ovulation or spermiation stimulated stress responses especially in female pikeperch, and therefore, all the procedures should be made to minimize the disturbance during the artificial spawning.     

Effects of turbidity on feeding of the young-of-the-year pikeperch (Sander lucioperca) in fishponds

The effect of water turbidity on the prey selection and consumption of the young-of-the-year (YOY) pikeperch in the planktivorous feeding stage was studied. Attention was paid particularly to the question of how the food selectivity depends on the size of YOY pikeperch and how the turbidity affects feeding in different size classes. Studies were carried out in ponds of two fish farms in Estonia over 4 years. Small cladocerans were the most preferred prey in the smallest pikeperch size class. In larger size classes, the most selected prey were the large cladocerans. Water turbidity affected the prey selection of the planktivorous pikeperch significantly. In more turbid environments, the larger zooplankters were more positively selected than the smaller ones. Turbidity decreased both total zooplankton consumption and Fulton's condition factor of fish only in the largest size class of pikeperch. The effect of turbidity on foraging and growth, and thus on the size of juvenile pikeperch of a particular year class is substantial under conditions where juveniles cannot shift from planktivory to piscivory.     

铜、锌对褐牙鲆鳃丝Na↑（+）-K↑（+）-ATPase活力的影响

以幼体褐牙鲆(Paralichthys olivaceus)为研究对象.Cu2+浓度梯度设置为0.10 mg/L、0.20 mg/L、0.50 mg/L和1.00 mg/L;Zn2+浓度梯度为1.00 mg/L、2.00 mg/L、5.00 mg/L和10.00 mg/L.实验周期为20 d.结果表明,在6 d内Cu2+(除1 mg/L处理组外)、Zn2+各处理组褐牙鲆鳃丝Na+-K+-ATPase活力随取样时间变化显著(P<0.05),且呈峰值变化,在24 h时达到最大值,然后缓慢下降;6～15 d,各处理组酶活力趋于稳定;而1 mg/L Cu2+处理组在12 h时酶活力达到最大值,3～15 d酶活力趋于稳定.2种重金属离子各处理组对鳃丝Na+-K+-ATPase活力的影响在同一取样时间差异显著(P<0.05),其影响程度与重金属离子浓度呈负相关,且1 mg/L Cu2+和10 mg/L Zn2+处理组在6～15 d酶活力与对照组差异不显著(P＞0.05).同时2种重金属离子在1～15 d内对褐牙鲆鳃丝Na+-K+-ATPase活力的诱导率表现为Zn2+(1 mg/L)＞Cu2+(1 mg/L).