丁鱥耗氧率和窒息点的初步研究

实验温度(26.1±0.5)℃,试验鱼平均体长10.60 cm,平均体质量13.09 g。丁鱥耗氧率为0.0849mg/(kg.h),窒息点为0.7598 mg/L。丁鱥的耗氧率呈明显的昼夜变化,白天平均耗氧率为0.0585 mg/(kg.h),夜间平均耗氧率为1.1161 mg/(kg.h)。丁鱥的耗氧量随着体重的增加而增加,耗氧率随着体重的增长而减小。在一定水温范围内,耗氧率随着水温的上升而增大。     

丁(鱼岁)不同组织的同工酶研究

采用聚丙烯酰胺凝胶垂直平板电泳,对丁的晶状体、心脏、脑、肾脏、肝脏、肌肉等6种组织进行了8种同工酶(LDH、MDH、α-AMY、G6PDH、ADH、AKP、EST、POD)的电泳研究,分析了各种酶的同工酶基因位点表达、亚基组成及酶谱表型,讨论了8种同工酶在组织中分布特异性的生理意义。结果表明:8种同工酶都存在不同程度的组织特异性;与其他硬骨鱼类相比,丁的8种同工酶具有明显的种属特异性。     

胭脂鱼幼鱼的耗氧率及窒息点研究

在自制的可控温密封式流水呼吸室内,对0+龄胭脂鱼(Myxocyprinus asiaticus)的耗氧率和耗氧量进行了测定,并对0+龄和1+龄胭脂鱼的窒息点和窒息过程作了分析。结果显示,平均体重6~7 g的0+龄胭脂鱼在15℃时的平均耗氧率和耗氧量分别为0.0585 mg/(g.h)和0.3567 mg/(尾.h);20℃时的平均耗氧率和耗氧量为0.1176 mg/(g.h)和0.8232 mg/(尾.h);昼间耗氧率与夜间耗氧率未显差异。15、20、25和30℃下0+龄胭脂鱼的窒息点分别为0.4921、0.8319、0.9356和1.5144 mg/L,25和30℃下1+龄胭脂鱼的窒息点为1.0738和1.1027 mg/L。     

丁（鱼岁）含肉率及肌肉营养成分分析

对13尾丁（鱼岁）的含肉率及营养成分进行了测定,并将其与国内外部分淡水经济鱼类相比较,对其营养价值作了综合评定.丁（鱼岁）的平均含肉率为72.4%,明显高于同科的鲤鱼和鲫鱼,且差异明显.肌肉中粗蛋白质含量为18.85%,粗脂肪1.73%;17种氨基酸总含量为18.03%,其中9种必需氨基酸的总含量为9.24%,占氨基酸总含量的51.25%;谷氨酸、天冬氨酸、甘氨酸和丙氨酸等四种鲜味氨基酸的总含量为6.97%,低于异育银鲫而高于鳜鱼、黄颡鱼、泥鳅和斑点叉尾鱼回.     

丁(鱼岁)肌肉脂肪酸组成的分析

采用气相色谱仪对丁(鱼岁)肌肉脂肪酸的组成进行了分析,结果显示,该鱼肌肉中可检测到16种脂 肪酸,且以 C16、 C18、 C22三个系列脂肪酸为主;饱和脂肪酸占脂肪酸总量的26． 29%,不饱和脂肪酸占脂 肪酸总量的73． 71%,其中单不饱和脂肪酸占53． 45%,多不饱和脂肪酸占20． 26%。     

丁(鱼岁)的池塘养殖试验

介绍了丁(鱼岁)的池塘养殖、水质调控、病害防治技术;养殖全程投喂自行配制的饲料,采取捕大留小的方法出售尾重400～500 g 的商品鱼,鱼种经过10个月的养殖,平均尾重达0.62 kg,平均产量7 950 kg/hm2,成活率93.4%,饲料系数1.57,养殖投入与产出比为1∶2.2.试验说明:丁(鱼岁)作为新引入的名优品种能适应浙江的地理环境,具有高产、高效的可行性.     

北方地区丁(鱼岁)苗种驯化关键技术研究

北方地区受气候影响,丁(鱼岁)(Tinca tinca L.)繁殖季节滞后,苗种培育期短,驯化困难,越冬前苗种规格过小,常常造成越冬大量死亡,无法提供大规格苗种和满足规模化养殖的苗种需求.为解决北方地区丁(鱼岁)苗种的提早驯化问题,设计了苗种放养密度相同、驯化规格不同,驯化规格相同、放养密度不同,驯化规格不同、放养密度不同3种驯化方法,进行了丁(鱼岁)苗种的驯食试验,比较不同驯化规格、不同放养密度对驯化时间的影响,以及提早驯化摄食对鱼种出池规格和产量的影响.结果表明,在丁(鱼岁)食性转化期(5～8cm)及时驯化更容易驯化成功;增加放养密度是缩短驯化时间的有效措施;提早驯化成功是培育大规格鱼种及增加产量的重要基础条件.     

丁(鱼岁)肠道及肝胰脏组织学研究

以体长4～6cm的丁幼鱼作为试材,用解剖、石蜡切片和显微摄像等组织学研究手段,对其肠道及肝胰脏组织结构进行了观察。比较了前、中、后肠粘膜皱褶的多少、疏密、高低以及杯状细胞的数量变化,说明肠道各段在消化过程中的不同作用;肝胰脏的组织学结构特点与鲤鱼相似,但胰腺细胞大部分都聚集在肝脏外部边缘和肠道的周围,只有一小部分弥散在肝脏之内,胰腺细胞间有较多胰岛。     

关于北方地区丁(鱼岁)Tinca tinca(Linnaeus)一年两次人工繁殖技术的探讨

丁(鱼岁)系欧洲淡水经济鱼类,于2004年4月引进,经过一年的鱼种培育,2005年人工繁殖试验获得成功,2006年一年两次人工繁殖又获成功,本文作扼要的介绍与探讨.     

军曹鱼幼鱼耗氧率与窒息点的研究

对平均体质量为16.0g～18.4g的军曹鱼在不同水温和盐度条件下的耗氧率进行了测定。结果表明,水温对军曹鱼的耗氧率有显著影响。盐度29‰时,水温从17℃上升到32℃,军曹鱼的耗氧率从0.357mg/g·h增加到0.880mg/g·h,水温(X)与耗氧率(Y)的关系可用幂函数表示:Y=0.0045X1.5197。在水温29℃时,军曹鱼的耗氧率随着盐度的变化而变化。此外,军曹鱼的耗氧率表现出较明显的昼夜变化规律,在中午前和傍晚后较高。水温对军曹鱼幼鱼的窒息点有显著影响。水温从21℃升高到33℃,窒息点从0.74mg/L增加到1.44mg/L。盐度对窒息点的影响不显著。     

The effect of feeding on oxygen consumption and ammonia excretion of juvenile tench Tinca tinca (L.) reared in a water recirculating system

The effect of feeding frequency (one, three, and continuous feeding), feed ration (0.2, 0.5, 0.8% of total fish biomass), and feeding per se on the oxygen consumption (OC, mg O₂ kg⁻¹ h⁻¹) and ammonia excretion (AE, mg TAN kg⁻¹ h⁻¹) of juvenile tench (body weight 15–19 g) and variations in these parameters in daily cycles were examined. Fish metabolism was studied in a recirculating system (rearing tanks of 0.2 m³, water temperature 23 °C). It was found that oxygen consumption and ammonia excretion depended significantly on feed ration. An increase of feed ration from 0.2 to 0.8% of fish biomass caused an increase of OC and AE from 126.80 mg O₂ kg⁻¹ h⁻¹ and 1.95 mg TAN kg⁻¹ h⁻¹ to 187.35 mg O₂ kg⁻¹ h⁻¹ and 8.80 mg TAN kg⁻¹ h⁻¹ (p<0.05). There was no dependence between feeding frequency and the mean rate of oxygen consumption. However, the relationship between feeding frequency and ammonia excretion by juvenile tench was statistically significant (p<0.05). Feeding frequency significantly affected daily fluctuations of AE and OC. It was found that diurnal variations in metabolic rates were strictly related to tench feeding, and the daily variations of AE were significantly higher than OC.     

丁(鱼岁)与家鱼混养试验

在家鱼池塘中分别进行了套养丁(鱼岁)鱼鱼种和商品鱼的试验.①鱼种混养:在三个塘中分别进行丁(鱼岁)鱼的鱼种单养、与白鲢鱼种混养和与草鱼鱼种混养,每个塘中平均每667m2放养的总鱼数为3万尾.到年底时,三个塘中的收获结果如下:成活率次序是草鱼塘＞白鲢塘＞单养塘(90.55%＞88.1%＞83.95%);规格大小依次为草鱼塘＞白鲢塘＞单养塘(41.8g＞38.15g＞32.0g).②成鱼混养:在白鲢主养塘和草鱼主养塘两种类型的池塘中平均每667m2放养52g左右的丁(鱼岁)鱼400尾,经12个月的饲养,在上述两种类型的池塘中混养丁(鱼岁)鱼的产量的高低次序依次是草鱼塘＞白鲢塘(222＞198.3kg/亩);成活率次序为草鱼塘＞白鲢塘(97.9%＞95%),平均规格大小的次序依次是草鱼塘＞白鲢塘(0.62kg＞0.599kg).     

Effects of different diets on juvenile tench, Tinca tinca (L.) reared under controlled conditions

In a laboratory experiment at 28 °C, four commercial starters (Carp Starter, Uni Starter, Perla Plus, Asta) were fed intensively to 11-month-old juvenile tench Tinca tinca of initially 41 mm TL and 0.70 g BW, over a period of 120 days. Frozen chironomid larvae were fed to fish below satiation as a reference diet for comparison of the fish body chemical composition. Final survival rates of 99–100% and satisfactory growth were attained with all dry diets, ranging from 73.3 (Carp Starter) to 84.8 mm TL (Asta) and from 5.39 (Carp Starter) to 8.09 g BW (Perla Plus). External body deformities of up to 96.4% specimens appeared in those fed Uni Starter, Carp Starter and Perla Plus, whereas 0% were recorded for Asta and chironomids. Fish in groups with deformities showed significantly elevated lipid content in their bodies, lower ash content and higher condition coefficient values. Juveniles in groups without deformities did not substantially change lipid content, but the ash content increased. Thus, among four dry diets studied, only Asta starter can be fed effectively and safely to juvenile tench reared intensively under controlled conditions.     

Does overfeeding affect tench Tinca tinca (L.) juveniles?

Duplicate groups of tench (Tinca tinca) juveniles (mean weight 0.69 g) were fed at 28 °C for 70 days either a commercial formulated diet, Futura, or frozen Chironomidae larvae at four levels: below satiation, at about satiation, above satiation and well above satiation. These are represented by the feeding groups F1–F4 and C1–C4, respectively. No mortality was observed throughout the experiment. In groups F2–F4 a considerable incidence of uneaten food (>40% observations), deformities of the caudal penduncle, retarded growth, elevated condition coefficient (>1.2), reduced amounts of minerals in the tissue (<10% dry matter), high C/N ratio (>5) and high caloric value of the tissue (>28 J mg⁻¹ dry matter) (the latter two suggesting excessive fat deposits), were found. The combination of these indices was indicative of overfeeding in fish fed the Futura diet at the daily doses ≥2.7% fish biomass. First symptoms of overfeeding: a considerable incidence of uneaten food, retarded growth, and elevated C/N ratio were observed in the group fed Chironomidae larvae at the highest level, (C4, wet Chironomidae 20.7% of the fish biomass daily, that is, 3.9% of dry chironomids per fish biomass and day). Thus, restricted daily doses of formulated diet not exceeding 2.5% fish biomass are recommended for tench juveniles aged 130–200 days post hatch. Safe daily doses of frozen Chironomidae (in terms of larvae dry weight) remain below 3.5% of fish biomass.     

Artificial insemination in tench, Tinca tinca L.

Abstract. The sperm of tench, Tinca tinca L., is characterized by a milky colour and consistency, and is of very low density. After collecting the sperm, motion of spermatozoa was recorded even without water activation. A better motility value (value 4·36 on average) was observed in spermatozoa collected in immobilizing solution (collecting medium) and stored for 3h, when compared with spermatozoa without collecting medium. Average total and relative numbers of spermatozoa were 12·16 × 10⁹ per male and 18·50 × 10⁹ per kg of body weight, respectively. When testing the effect of activating solution in artificial propagation of tench, the highest fertilization rates (81·3 and 85% in two cases) were found for NaCl solution with an osmotic concentration of 34 or 69 mOsmol and for fresh water, respectively. The fertility rate was reduced significantly ( P < 0·01) by any increase above 105 mOsmol in NaCl concentration in the activating solution. In the tests of optimal method of artificial fertilization, the highest hatching rate of sac fry (71·35%) was found in sperm collected into immobilizing solution. The application of immobilizing solution significantly increased the number of sac fry at the levels P < 0·1 and P < 0·01, if compared with intact sperm stored for 3 h and fresh sperm, respectively.     

欧洲丁鲼苗种培育技术研究

<正>欧洲丁鱥(Tincatinca),又名丁桂,广泛分布于欧洲各地,在欧洲有皇家宠鱼之称,在我国仅分布于新疆额尔齐斯河流域。该鱼为淡水底栖鱼类,广温性,食性与鲤相近,杂食性,肉质鲜美,生长速度较快,耐低氧能力强,经驯化能较好地摄食人工配合饵料,易于养殖。福建省清流县三合农渔牧生物科技有限公司自2006年引进该鱼后,先后成功开展了人工繁育及养殖技术研究。2008年采取苗种分级培育技术,培育效果取得了明显提高。现将其苗种培育技术总结如下。     

Studies on sperm of diploid and triploid tench, Tinca tinca (L.)

The tench Tinca tinca is an interesting fish from the viewpoint of polyploidy and related atypical reproduction aspects. Triploid tench were produced artificially. Studies of spermiation as well as of sperm motility and structure were performed on several triploid and diploid males simultaneously with individual experimental crosses with diploid females to define their reproductive capacities. The testes of triploids visually looked less developed in the most of cases with lower sperm production (0.05 cm³ sperm per male), GSI and weight of testes compared to diploids (0.58 cm³ sperm per male). Analysis of variance showed significant influence of ploidy level on the percentage of motile spermatozoa. Triploidy did not change percentage of live spermatozoa and velocity of spermatozoa at the first time of sperm movement. The study of sperm structure by scanning electron microscopy revealed that most sperm cells were of normal structure with some anomalies. Sperm heads of triploid and diploid males were mostly round-shaped, 1.86±0.2 and 1.6±0.18 μm in diameter. The midpiece of triploid spermatozoa was slightly narrower than that of diploid ones with typical cylindrical shape. Flow cytometry revealed sperm cells of triploids to be largely aneuploid (1.47 n) with high mosaic DNA, oscillating from haploid DNA content (1.0 n) to diploid DNA content (1.9 n). Experimental crosses between triploid males and diploid females revealed that these males were capable to stimulate effective development with relatively high level of fertilization and hatching rates from 0 to 70%. In conclusion, triploidization does not seem to guarantee sterility of tench.     

Insemination, fertilization and gamete management in tench, Tinca tinca (L.)

Various procedures for artificial insemination in tench, Tinca tinca (L.) were re-examined with evaluation of fecundity of males and females among different tench strains. The objectives of this study were to enhance fertilization and hatching rates through optimization of the activation solution, the insemination process, the activation of gametes, and the elimination of eggs stickiness. Sperm for all experiments was collected directly into immobilization solution of modified Kurokura solution containing 180 mM of NaCl and stored at 2 °C for 2.5–5 h prior to the experiment. When dechlorinated tap water was used for activation a gamete ratio of 1150 spermatozoa per egg showed the best significant fertilisation and hatching rates. Optimal ratio between eggs (weight in g) and activation solution (in cm³) was 1:1. Different concentrations of activation solutions such as NaCl from 0 to 68 mM (0–136 mOsmol kg⁻¹) without buffer statistically decreased fertilization and hatching rates. The activation solution containing 17 mM of NaCl, 10 mM Tris–HCl, pH 8 and 9 significantly increased fertilization and hatching rates compared to dechlorinated tap water of pH 7 or activation solution containing 17 mM of NaCl, 10 mM Tris–HCl, pH 6 and 7. Adhesiveness of the eggs was successfully removed by incubation in Alcalase and activity: 3.16 Anson units per cm³.     

Dynamics of ammonia excretion in juvenile common tench, Tinca tinca (L.), during intensive rearing under controlled conditions

This paper presents the first data on ammonia excretion by fed and starved juvenile common tench. The aim of the study was to determine the amount of ammonia excretion by juvenile common tench Tinca tinca (L.), fed with a commercial feed under intensive rearing conditions. Rearing was conducted for a period of 4 weeks at a water temperature of 27 °C. On the test day, the amounts of ammonia excreted by starved fish (over 12 h: control group) and fish fed with a morning feed dose (3 % of biomass: experimental group) were determined at 1, 3, 5, 7, 9 and 11 h after feeding. Ammonia excretion measurements were taken in 7-day intervals. Despite the increased growth rate in successive weeks of experiment, the amount of ammonia excreted by the fish was always at a similar level within the control (maximum 0.26 mg g^?1) and the experimental group (maximum 0.39 mg g^?1). This paper presents for the first time reliable amount of ammonia excreted by fed and starved juvenile common tench. The obtained results may also increase the effectiveness of intensive rearing procedures (taking into account stocking density and feeding regime) and allow to design the most effective biofiltration capacity of recirculating aquaculture systems for the commercial production of this species.