室内模拟条件下的胃含物法测定玉筋鱼摄食与生态转换效率

研究在室内大型玻璃钢水槽中进行 ,在流水条件下 ,以卤虫幼体为饵料 ,应用Eggers模型研究了黄、东海主要小型经济鱼类玉筋鱼(Ammodytespersonatus)的摄食、生长和生态转换效率等生态能量学特征。结果表明 ,玉筋鱼体重与空消化道重量的关系可用指数函数W =0 .2 71e79.984·ESW加以定量描述 ,通过这一定量关系 ,可推导出其瞬时全消化道内含物量计算公式为St=1 0 0× [SW -(LnW +1 .30 5) / 79.984] /W ;全消化道内含物随时间变化的拟合曲线为St=1 .784e 0 .2 1 4t,公式两边取负对数可求得瞬时排空率为 0 .2 1 4g/ 1 0 0 g·h (W .W .) ;按Eggers模型可求得日摄食量为 2 2 .53g/ 1 0 0g·d (W .W .)或 60 .1 4kJ/ 1 0 0 g·d ;从玉筋鱼的平均日生长量实测值为 3.45g/ 1 0 0 g·d (W .W .)或 2 2 .94kJ/ 1 0 0 g·d,可求得其生态转换效率为 1 5.34 % (W .W .)或 38 1 4 %kJ。     

现场胃含物法测定鲐的摄食与生态转换效率

2000年7月至9月在山东半岛南部沿海鲐繁殖海域的鱼类养殖网箱中,应用胃含物法测定了渤海优势鱼种鲐的摄食、生态转换效率等生态能量学参数。结果表明,(1)在饵料不受限制时,鲐的摄食量和生长呈不规则波浪式变化,其波距比较恒定,但波高变化较大;(2)鲐的瞬时胃含物重量随时间变化可用指数模型St=9.0876e-0.1868t描述,瞬时排空率Rt=0.1868g·(100g)-1·h-1(按湿重计算);(3)按Eggers公式可求得鲐日摄食量Cd=(15.60±2.55)g·(100g·d)-1(按湿重计算)或(69.84±11.42)kJ·(100g)-1·d-1;(4)实验期间鲐体重随时间的变化可用线性方程Wt=2.23t+16.71描述,由该式可求得其相对平均日生长量Gd=3.72g·(100g)-1·d-1或30.00kJ·(100g)-1·d-1;(5)由于已知的平均日摄食量和平均日生长量,可求得鲐生态转换效率Eg=23.85%(按湿重计算)或42.96%kJ。     

大菱鲆正常代谢水平及节律性的研究

对工厂化养殖的不同规格大菱鲆(Scophamus maximus Linnaeus)的日常代谢进行了研究。结果表明,4种规格的大菱鲆表现出相同的代谢规律性,摄食对大菱鲆的代谢有明显的影响,摄食后代谢率呈迅速上升的趋势。在摄食后3～9 h内代谢率出现第1高峰值,在凌晨3:00～6:00(摄食后21-24 h)出现第2高峰值,代谢率昼、夜之间的差异不显著(P>0.05)。体重对大菱鲆的代谢有着显著的影响,4种规格9.69±3.35g、33.34±8.34g、130.18±26.75g和264.11±35.79g的大菱鲆日平均耗氧率分别为0.2702±0.0225、0.1880±0.0189、0.1592±0.0436、0.1033±0.0184mgO2/g·h,日平均氨氮排泄率分别是0.6496±0.0303、0.4560±0.0669、0.3744±0.0320、0.2831±0.0662mgN/100g·h,随着体重的增加,单位体重的代谢率呈下降的趋势(P<0.05)。     

暗纹东方鲀鱼苗耗氧率和窒息点的初步研究

对暗纹东方鱼屯两个规格鱼苗的耗氧量、耗氧率和窒息点进行了测定。结果显示 :在水温 31～34℃ ,pH 6 5～ 6 8条件下 ,平均全长 2 36cm、体重 0 4 2 9g的鱼苗 2 4h平均耗氧量 0 32 1mg/ (尾·h) ,耗氧率 1 14 9mg/ (g·h) ,窒息点 1 30 9mg/L ;平均全长 3 4 9cm、体重 0 5 6 9g的鱼苗 2 4h平均耗氧量 0 837mg/ (尾·h) ,耗氧率 0 96 8mg/ (g·h) ,窒息点 1 4 86mg/L。     

三疣梭子蟹幼蟹的摄食和碳收支

20 0 2年 6～ 9月 ,在自然水温 (2 4 0、2 4 9和 2 6 3℃ )和投喂鹰爪虾虾仁的条件下测定了 3个体重组 (0 73± 0 15 g、1 5 5± 35 g和 3 75± 0 5 2g)三疣梭子蟹幼蟹的摄食和碳收支。结果表明 ,温度和体重对三疣梭子蟹幼蟹的摄食量均有明显影响 ,其中体重的影响更为显著。以湿重和干重(比能值 )计算得到三疣梭子蟹幼蟹的特定生长率 (SGR)和生态转换效率 (Eg)分别为 2 5± 1 33～3 0± 0 95和 19 4± 4 8～ 5 9 4± 2 2 9,2 8± 0 73～ 4 3± 2 2 8和 10 1± 2 3～ 2 9 1± 12 4。在三疣梭子蟹幼蟹的C收支模式中 ,代谢C所占的比例最大 ,占总摄食C的 5 0 %以上 ,其次是生长C ,约占总摄食C的 2 8% ,蜕壳和排粪消耗的C的比例较小 ,一般少于 5 %。三疣梭子蟹幼蟹的个体大小和水温是影响C收支的重要因素 ,其中温度是主要因子。随个体的增大和试验水温的升高 ,三疣梭子蟹生长C占总摄食C的比例减少 ,代谢C的比例增加 ,蜕壳C和排粪C所占的波动较小。     

斑鰶的摄食与生态转换效率

1998年9月在山东省莱州市过西镇,对养虾池中斑鰶(Clupanodon　punctatus)(叉长49.0～130.0mm,体重1.38～27.39g)的摄食与生态转换效率进行了研究。采用ElliottPersson(1978)方法,从研究斑鰶的摄食周率出发,对其排空率、摄食率以及食物转换效率进行了定量。结果显示,斑鰶属白天摄食类型,摄食高峰在每日的15∶00～18∶00时。从18∶00时至翌日3∶00时,全消化道内含物(占体重的百分比)随时间的变动为DCW=3.086 2·e0.270 9T,排空率为0.270 9gw.w./100gw.w.·h。用指数函数能更好地描述斑鰶的摄食率与体重的相关关系,C=4.162 7·e0.120 4W,Ｒ2=0.844 8。斑鰶个体日均摄食量为0.904 6g,生长率为0.149 4g/d,食物转换效率为16.5%,能量转换效率>30%。研究结果表明,应用ElliottPersson模型研究某些白天摄食类型的鱼类摄食时,可以只利用从傍晚到黎明这段时间的全消化道(或胃)内含物的变动资料。根据日粮和季节生物量,计算出渤海斑鰶的年饵料需求量约为16万t,这意味着渤海斑鰶每年可把大约16万t的海洋沉积物通过摄食搬运离开海底,对生态系统的沉积物再悬浮以及水底物质交换具有重要意义。作者认为,斑鰶的沉积碎屑食性和杂食性,使它对食物环境的变化(如浮游动物大量减少)具有灵活适应性,保证了种群的大量增     

中华倒刺鲃鱼种耗氧率和窒息点的初步研究

在一定水温条件下 ,对中华倒刺鱼种 (1 5 5～ 7 2 8g)进行了耗氧率和窒息点的测定 ,结果表明 :耗氧率随鱼体体重的增加而降低。平均体长 4 35cm ,均重 1 5 5 g的个体 ,平均耗氧率为 0 42 0 2mg/g·h ,窒息点为0 441 2mg/L ,平均体长 7 2 2cm ,均重 7 2 8g的个体 ,平均耗氧率为 0 2 2 2 2mg/g·h ,窒息点为 0 8831mg/L。水温与耗氧率呈正相关。     

栉孔扇贝生理能量学研究

在室内实验条件和现场模拟条件下对栉孔扇贝的耗氧率、排泄率、摄食率、同化率和能量收支进行了较为系统的研究。结果显示 ,在适宜的温度范围内 ,栉孔扇贝的耗氧率、排氨率和摄食率均与温度成正比 ,与体重成幂函数关系 ,体重与耗氧率、排氨率和摄食率的关系均可用幂函数关系式Y=aWb表示。在 8～ 2 8℃温度范围内栉孔扇贝的耗氧率、排氨率和摄食率均随温度的升高而增大 ,2 3℃时耗氧率和摄食率达到最高值 ,2 8℃时下降 ,而排氨率则呈持续升高的趋势 ,其变化幅度分别为 0 4 8～ 9 0 9mg/ g·h、0 0 5～ 1 0 1mg/ g·h和 1 0 7～ 11 6 6mg/ g·h。栉孔扇贝的摄食率随藻类密度的增加而增加 ,符合关系式 :IR =4 78C0 36 6 (R2 =0 97,P <0 0 5 )。栉孔扇贝的同化率与饵料密度呈负相关关系 ,而与饵料质量呈正相关关系 ,其相关关系分别为 :AE =4 7 6 5C- 0 30 9(R2 =0 96 )和AE =5 1 6 8lnX - 112 38(R2 =0 97)。栉孔扇贝的个体大小是影响能量收支各组分比例的主要因素 ,随个体增大呼吸能增大 ,生长能减小。在能量收支方程中 ,呼吸能占总摄食能的 4 4 2 %～5 1 7% ,排粪能为 31 4 %～ 36 8% ,生长能为 12 7%～ 2 1 7% ,排泄能小于 2 %。     

全雄太阳鲈耗氧率与窒息点的研究

平均体重0 68g的全雄太阳鲈24h平均耗氧率为0 830mg/g·h,平均体重6 45g的全雄太阳鲈的平均耗氧率为0 416mg/g·h,全雄太阳鲈的耗氧率随体重的增加而减少。不同规格的全雄太阳鲈的窒息点不同,3cm以下全雄太阳鲈的窒息点为1 101mg/L,3～5cm为0 697mg/L,5～6cm为0 402mg/L,6～7cm为0 232mg/L,8～9cm的为0 175mg/L。     

方氏云(鱼尉)的排空率研究

在实验室内约 15℃水温下 ,投喂以细长脚 (Themisto gracilip es)为主要成分的天然饵料 ,对成体方氏云 (Enedrias fangi)进行了排空率研究。对 3种排空模型拟合效果的分析显示 ,平方根模型最符合方氏云的排空。在不摄食阶段 ,全消化道内含物的量 (CDW)随时间 (TIME)的变化可以下式描述 :CDW0 .5=3.890 - 0 .175· TIME(R2 =0 .939,p<0 .0 0 0 1)。方氏云的排空率为 0 .175g/10 0 g wet· h。     

大海马在人工养殖条件下的生长速率

报道了在人工养殖条件下,大海马(Hippocampus kuda Bleeker)的体长与体重的相对生长率、生长比率及生长速度与饵料、水温等环境因子的关系。结果表明，大海马生长高峰期为5～11月，群体体长月平均增长率为12.20％，体长特定增长率为15.92％；体重月平均增重率为15.87％，体重特定增重率为27.70％，群体增重倍数为13.8。大海马体长呈逻辑斯蒂曲线增长，关系式为L＝192.3460／(1＋e     

海马网箱养殖试验

本文报道海马网箱养殖试验。海马可以进行网箱养殖，需要选择合适的养殖水环境，改进网箱设置，采用适当的饵料和投喂方式，防治病害，提高成活率。     

Feed intake, growth and feed conversion efficiency of Atlantic halibut, Hippoglossus hippoglossus (L.)

The individual food intake of each fish in each of four groups of Atlantic halibut, Hippoglossus hippoglossus (L.) (mean weight: 422 g) was monitored by direct observation over a period of 21 days. Gross feed conversion efficiency (= growth·feed intake^?1), net feed conversion efficiency and maintenance ration were estimated by regression analysis. Specific growth rates were found to be linearly related to weight-specific consumption at a temperature of 8–9°C: growth = 1.922· feed intake ? 0.242. Maintenance ration was 0.126% of body weight day^?1. The gross feed conversion efficiency increased asymptotically with increasing feed intakes and growth rates, and was found to approach 1.9 at high growth rates (0.5 on a dry weight basis). One feeding per day seemed to be sufficient for maximum food intake and growth rate.     

温度对大海马摄食行为及生长速率的影响

选取体质良好、活力强的大海马(Hippocampus kuda Bleeker),体重(3.075 g±0.16 g)、体全长(11.55 cm±0.31cm)。设置18℃、23℃、28 3℃个实验组和1个对照组(CT组:自然变温),每组3个重复,实验周期28 d。结果显示,大海马在23℃时生长速率最快,摄食活跃;28℃大海马反应最迅速(5.8 s±0.74 s),摄食量最大(153.92 g±10.33 g),活动频繁,泳速大;而18℃和自然变温条件下对食物的反应不敏感,多缠绕在附着物上,摄食时呈聚集式分布;23℃和28℃时,相对活跃,会主动游向饵料摄食,摄食效率较高。综上所述,温度的改变对大海马的生长速率及摄食行为均有一定影响;在适宜温度下,大海马的活力大,摄食量多,生长速率相对较快。本研究旨在为大海马饵料开发和养殖环境优化提供科学数据。     

Growth of cultured seahorses (<Emphasis Type="Italic">Hippocampus abdominalis</Emphasis>) in relation to feed ration

This investigation examined the effect of varying feed ratios on cultured seahorse (Hippocampus abdominalis) growth and survival using frozen mysids (Amblyops kempii) at daily feed rations of 5, 10, 15 or 20% wet body weight. Feeding these different feed rations did not result in any significant difference in seahorse standard length after 3 months. However, seahorses fed the 10–20% rations were heavier and with higher condition factor (CF). Based on the total amount of frozen mysids offered to the seahorses, the food conversion ratio (FCR) became less efficient with increasing feed ration. However, when the actual mysid consumption was factored in there were no significant differences in FCR. There was a significant difference in daily specific growth rate (SGR), with the 5% ration having the lowest SGR. On a cost/benefit basis, based on the total amount of mysids offered the most cost effective ration for daily length and weight increase was the 5% ration. With actual mysid consumption taken into account, cost/benefit value favoured the 5 and 10% feed rations. Survival was 100% across all treatments. Based on this, a feed ration of 5–10% wet body weight per day of frozen mysids is recommended for cultured H. abdominalis     

Biochemical composition of the wild and cultured seahorses, Hippocampus kuda Bleeker and Hippocampus trimaculatus Leach

The biochemical composition of wild and cultured seahorses Hippocampus kuda Bleeker and Hippocampus trimaculatus Leach was analysed in this study. The crude protein contents (% dry weight) of wild seahorses were high: 72.7±2.5% in H. kuda and 78.5±4.2% in H. trimaculatus . The crude lipid contents (% dry weight) of wild and cultured seahorses (1.1±0.1 vs. 1.4±0.2 for H. kuda and 1.2±0.1 vs. 1.2±0.2 for H. trimaculatus ) were low and did not differ significantly ( F _3, 12=1.461, P =0.12). The essential amino acids and flavour-enhancing amino acids in wild seahorses were higher than those in cultured seahorses, although the essential amino acid index in wild and cultured H. kuda and H. trimaculatus were generally low. The total amino acid content decreased with growth in cultured H. trimaculatus ( F _3, 12=14.927, P <0.05). The poly-unsaturated fatty acid (PUFA) contents in wild and cultured H. kuda and H. trimaculatus were 21.69%, 37.72%, 21.39% and 33.89% respectively. The fatty acid content in seahorses first decreased and then increased with growth both in wild and in cultured H. trimaculatus . The PUFA/saturated fatty acid ratio was 1.31 in cultured H. kuda and 0.87 in cultured H. trimaculatus . The trace metal concentrations in the wild seahorses were relatively low. The results presented in this study provide biochemical information necessary for understanding the medicinal value of H. kuda and H. trimaculatus and for elucidating the potential dietary requirements for their culture.     

Grow-out of juvenile seahorse Hippocampus kuda (Bleeker; Teleostei: Syngnathidae) in illuminated sea cages

This paper examines the feasibility of rearing 10–15-day- and 0.7–1.5-month-old seahorse Hippocampus kuda in illuminated sea cages to continue existing hatchery protocols to mass produce H. kuda for trade and enhance depleted wild stocks in their natural habitats. Thawed Acetes (a planktonic crustacean abundant in inshore seas) was fed to juvenile seahorses in lighted and unlighted sea cages while one group in lighted cages was not fed Acetes . After 10–12 weeks of rearing, both mean body weight and stretch height increased in all treatment groups, with lighted cage-reared seahorses fed Acetes being heavier (2 g) and longer (8 cm) than the other two treatment groups. Although instantaneous growth rates declined during the rearing period, these were generally higher among Acetes -fed seahorses in lighted cages (0.02–0.07) compared with those in the unlighted cages with Acetes and lighted cages without Acetes feeding. Mean survivorship in all groups ranged from 9% to 74% after the trials, but mean survivorship of juveniles in lighted cages with Acetes feeding (9–74%) was consistently lower than the two treatment groups as a likely result of crustacean and piscine predators being attracted by light and the odour of leftover Acetes in the lighted cages. These results demonstrate that light-attracted zooplankton prey supplemented by Acetes feeding may provide essential nutrients for the growth of H. kuda juveniles in illuminated sea cages. With further improvement in the grow-out protocol, it may provide a possible alternative livelihood to seahorse fishers and sufficient seed to re-populate depleted wild stocks of H. kuda .     

投喂频率对雌雄分化后灰海马生长发育、饵料转换效率及消化酶活力的影响

以外形刚可辨别雌雄的灰海马(Hippocampus erectus)为研究对象,冰冻糠虾(Mysis spp.)为饵料,研究不同投喂频率(A:1次/d、B:2次/d、C:3次/d和D:4次/d)对雌雄分化后灰海马生长、发育、饵料转换效率及消化酶活力的影响。结果表明,整个实验期间灰海马的体质量特定生长率(WSGR)和体高特定生长率(HSGR)均随投喂频率的增加而增加,其中A、B和C3组雄海马的WSGR和HSGR均高于雌海马,而D组雌雄间差异不显著(P>0.05);随时间的推移,D组雌海马的WSGR和HSGR均呈先增后减趋势,而其它3组均呈下降趋势,且第1周的WSGR和HSGR均显著高于第5周(P<0.05)。B组灰海马的饵料转换效率(FCE)显著高于其它各组(P<0.05)。A组雌海马的性腺发育早于其它各组。A组灰海马的脂肪酶、淀粉酶和胃蛋白酶活力均显著高于其它各组(P<0.05),且该组雌海马的上述3种酶活力均显著高于雄海马(P<0.05);各组灰海马的胰蛋白酶活力相互之间差异不显著(P>0.05)。因此,在灰海马的商业养殖中应综合考虑养殖效益,根据不同发育阶段选择不同的投喂方式。而在亲体培育时,选择4次/d的投喂频率最佳。     

Biochemical Composition of Six Seahorse Species, Hippocampus sp., from the Chinese Coast

The biochemical composition of six seahorse species from the Chinese coast was analyzed in this study. The crude protein content (% dry weight) of Hippocampus kuda, Hippocampus trimaculatus, Hippocampus kelloggi, Hippocampus spinosissimus, Hippocampus histrix, and Hippocampus comes was 70.70 ± 2.12%, 77.59 ± 1.06%, 78.31 ± 1.74%, 71.15 ± 1.32%, 68.07 ± 1.96%, and 76.59 ± 3.25%, respectively. The major amino acids (>5% of the total) in seahorses were arginine, aspartic acid, glutamic acid, alanine, and glycine, and there were significant differences in essential amino acids (EAA) (as % of total protein) among the six species (P < 0.05). The scores of EAA were balanced in the seahorse species, and the essential amino acid indexes of the six species were 41.63, 40.89, 44.84, 39.60, 39.31 and 45.45, respectively. The content of flavor‐enhancing amino acids of the six seahorse species was generally high, ranging from 28.16 ± 1.12% in H. histrix to 32.90 ± 2.17% in H. kelloggi (P < 0.05). The total lipid content was generally low, ranging from 0.96 ± 0.08% in H. histrix to 2.02 ± 0.24% in H. comes. The most abundant fatty acid was C16:0, ranging from 15.04 ± 0.67% in H. trimaculatus to 31.04 ± 4.32% in H. spinosissimus. The combination of eicosapentaenoic acid and docosahexaenoic acid as the fraction of the total fatty acids was high (0.14–0.35). The polyunsaturated fatty acid/saturated fatty acid ratio ranged from 0.40 in H. kuda to 1.19 in H. histrix. The trace metal concentrations in the seahorses were generally low. The six seahorse species examined provide a food source for humans with low fat, high protein, good levels of EAA, and high beneficial trace elements. These results are valuable in developing diets for culturing seahorse species.     

Frozen mysids as an alternative to live Artemia in culturing seahorses Hippocampus abdominalis

This investigation examined the effects on growth and survival of seahorses Hippocampus abdominalis Leeson 1827 fed a 25% body weight (wet weight) daily ration of live Artemia sp. enriched with Algamac‐3050, frozen mysids Amblyops kempi or a combination of live enriched Artemia and frozen mysids. After 3 months there was no difference in seahorse length, wet weight, condition factor (CF), or food conversion ratios (FCR) between the treatments. Mean daily specific growth rate (SGR) was higher for the Artemia‐only treatment than for the mysid‐only treatment (P<0.05). FCRs ranged from 6.14 g to 8.72 g dry weight of food required to give a 1‐g dry weight increase in seahorses. There was no difference in survival between treatments. Fatty acid analysis revealed that mysids had a higher percentage composition of EPA, 20 : 5n‐3, and DHA, 22 : 6n‐3, but a lower composition of AA, 20 : 4n‐6, than enriched Artemia. Percentage n‐3 highly unsaturated fatty acids (HUFAs) in mysid levels were approximately twice that of Artemia. Proximate analysis revealed mysids to be higher than the enriched Artemia in protein and fats, and lower in water content. This experiment demonstrates that, although no growth advantage was derived from the use of frozen mysids, they can be used successfully as an alternative food to live enriched Artemia for H. abdominalis. The use of frozen mysids is highly recommended in commercial seahorse culture if the seahorses are to be sold into the live aquarium trade, as this may increase their chances of survival after sale.