对虾养殖的曙光

本文综述了我国在虾病病原、病理及诊断方面的进展,例举了一些虾病防治方面的成功经验,并认为对虾养殖业的发展出现了曙光。     

中国对虾产业现状及相关研究综述

中国对虾产业在国际上具有重要地位，但近年来中国对虾出口形势面临从未有过的巨大挑战，因此，了解我国对虾产品、产业的现状，加大我国对虾产品与产业的研究，对我国对虾产业增强竞争能力和可持续发展具有一定意义。     

Effects of Feeding Diets Containing 34 or 38% Protein at Two Feeding Frequencies on Growth and Body Composition of Channel Catfish

Channel catfish, Ictalurus punctatus, fingerlings were stocked (13,585 fish/ha) in twelve 0.04-ha earthen ponds and fed to satiation with diets containing either 34 or 38% protein (79.1 or 88.8 mg protein/kcal), either once or twice daily for 170 days. Experimental diets with the proper levels of essential amino acids, vitamins, and minerals were formulated by a commercial feed mill. No significant differences (P < 0.05) in growth and body composition of channel catfish were found when analyzed by protein level, feeding frequency, or their interaction. Average individual fish weight at harvest was 461 g. Net production was 4,152 kg/ha. Percentage protein, fat, and ash in the waste (head, skin, viscera, and frame) were 41.5, 41.4, and 12.2%, respectively, while fillet had 65.7, 30.4, and 4.0%, respectively.     

海水和淡水养殖凡纳滨对虾呈味物质的比较分析

对使用同种饲料喂养的海水和淡水养殖凡纳滨对虾(Litopenaeusvannamei)进行了感官评价、一般成分和呈味物质分析。海水养殖对虾感官评价总体得分高于淡水养殖对虾,海水养殖对虾在鲜味、甜味上优于淡水养殖对虾,而淡水养殖对虾带有明显的土腥味(P<0.01)。海水养殖对虾的灰分高于淡水养殖对虾,粗蛋白、水分及有机酸含量两类对虾差异不大。通过分析氨基酸、核苷酸、甜菜碱和有机酸等呈味物质,发现主要是谷氨酸、AMP、IMP、甜菜碱这几种物质对两类对虾的口味差异起着重要作用,其他成分作用不明显。     

Biosecure Shrimp Feeds and Feeding Practices: Guidelines for Future Development

For the purposes of this paper, biosecure shrimp feeds and on‐farm feeding strategies refer to the “feed, whether live, fresh, or formulated, and the management of the feed on the farm, should not be an entry point of potential pathogens to the shrimp and/or to the culture system.” The paper reviews the different feeds commonly used for the production of farmed shrimp and discusses their potential risks from a disease perspective, including the use of live hatchery and nursery feeds, the use of live and/or fresh food organisms for the production of broodstock, and the use of dry formulated shrimp feeds for shrimp growout operations. In addition, the paper discusses the critical role played by feed‐processing techniques for the pasteurization and destruction of pathogens within shrimp feeds and the need for nutritionists to formulate feeds for optimal nutrition and health, and not just for optimal growth. The importance of the development and implementation of good on‐farm feed management practices by farmers is discussed, including the prohibition of the top‐dressing of pelleted feeds on farm by farmers with unapproved feed additives such as antibiotics. Finally, the paper discusses the responsibilities of farmers, feed manufacturers, and traders regarding the development and use of recommended biosecure shrimp feeds and feeding practices.     

Water quality and plankton densities in mixed shrimp-mangrove forestry farming systems in Vietnam

Water quality and plankton densities were monitored in shrimp ponds at 12 mixed shrimp‐mangrove forestry farms in Ca Mau province, southern Vietnam, to detail basic water chemistry and assess whether conditions are suitable for shrimp culture. In general, water quality was not optimal for shrimp culture. In particular, ponds were shallow (mean ± 1SE, 50.5 ± 2.8 cm), acidic (pH < 6.5), had high suspended solids (0.3 ± 0.03 g l^?1), low chlorophyll a/phytoplankton concentrations (0.2 ± 0.05 µg l^?1 and 8600 ± 800 cells l^?1 respectively) and low dissolved oxygen (DO) levels (3.7 ± 0.15 mg l^?1). Eight out of the 12 farms sampled had potentially acid sulphate soils (pH < 4.2). Salinity, DO and pH were highly variable over short time‐periods (hours); DO in particular was reduced to potentially lethal levels (1–2 mg l^?1). Seasonal variations in water chemistry and plankton communities (i.e. salinity, DO, phosphate, temperature, phytoplankton and zooplankton densities) appear to be driven by differences in rainfall patterns. The presence or absence of mangroves on internal pond levees (‘mixed’ versus ‘separate’ farms) and the source of pond water (rivers versus canals) were of lesser importance in determining water quality patterns and plankton biomass. Zooplankton and macrobenthos densities were sufficient to support the current (low) stocking densities of shrimp. However, natural food sources are not adequate to support increases in production by stocking hatchery reared post larvae. Increasing productivity by fertilization and/or supplemental feeding has the potential for adverse water quality and would require improvements to water management practices. Some practical strategies for improving water quality and plankton densities are outlined.     

Effects of ammonia on growth and molting of Litopenaeus vannamei postlarvae reared under two salinity levels

ABSTRACT

Litopenaeus vannamei postlarvae were exposed to 0, 6, 13, and 19 mg/L total ammonia nitrogen (TAN) treatments. After 45 days, shrimp weight and length were lowest under TAN concentrations of 13 and 19 mg/L (P ≤ 0.05). Maximum weight gain was observed in control and 6 mg/L treatments. Mortality was highest (80.55 ± 4.80%) under 19 mg/L reared in 35 ppt salinity. Average intermolt periods of PLs exposed to 0, 6, 13, and 19 mg/L TAN were 11.5 ± 0.7, 10.8 ± 1.3, 9.4 ± 1.0, and 8.7 ± 0.6 days under 35 ppt and 11.1 ± 0.5, 10.7 ± 0.6, 10.1 ± 0.5, and 9.5 ± 0.2 days under 45 ppt salinity. Although TAN increased postlarvae molting frequency, its negative effects on the shrimp growth and survival of PLs was directly linked to its concentration and exposure duration. Higher salinity reduces the effects of ammonia and increases the survival.     

跑道式南美白对虾养殖池中弧菌的数量动态

采用TCBS平板计数法对南美白对虾跑道式养殖池和土塘养殖塘水样弧菌数量进行了一个养殖周期的连续监测。结果表明:跑道式养殖池水体中弧菌数在放苗后的前70 d均较低,随后迅速增加并维持在一个较高水平,变化幅度为15.0~1.42×104cfu/ml,平均3.96×103cfu/ml,平均数比土塘高2倍。跑道式养殖对虾始终未发病,跑道式养虾病害少,产量高。     

Substituting fishmeal with mixtures of wheat,corn and soya bean meals in diets for the white leg shrimp,Litopenaeus vannamei (Boone): effect on production parameters and preliminary economic assessment

We analysed the effect on production and economic performance of juvenile Litopenaeus vannamei of isoproteic diets substituting fishmeal by 25%, 50%, 75% and 100% with mixtures of wheat, soya bean and cornmeals. In a laboratory trial, 10 juveniles m^?2 (1.1 ± 0.1 g) were reared in 60‐L plastic containers using a recirculation system for 90 days. Three replicates were used to test each diet. A commercial diet serving as a reference and the diet with the highest content of essential amino acids (50% substitution, 6.46 ± 1.1 g) produced significantly higher shrimp final weight (7.12 ± 0.9 g, P < 0.05). There were not significant differences in specific growth rate and mean survival (85.9 ± 0.2%, P > 0.05). In a pond trial, 10 shrimp m^?2 (1.08 ± 0.3 g) were cultivated in 1.5 m^?3 cages for 35 days, testing the diets in triplicate. Final weight was significantly higher (P < 0.05) when 100% substitution was used (10.89 ± 0.24 g), while survival did not differ significantly among diets (P > 0.05). The optimal level of substitution was estimated at 86.0%. Apparently, nutrients contained in the diets combined well with natural feed available in the pond, up to a point where 7.3% of fishmeal inclusion is recommended. An economic analysis showed that 100% substitution produced the best results. We conclude that mixtures of wheat, corn and soya meals are potential alternatives to replace fishmeal effectively in diets for L. vannamei.     

Dietary protein level and natural food management in the culture of blue (Litopenaeus stylirostris) and white shrimp (Litopenaeus vannamei) in microcosms

The effect of dietary protein level and natural food management on the production parameters of blue and white shrimp, as well as on water quality, was evaluated in a microcosms system (plastic pools simulating aquaculture ponds). Two experimental trials were carried out in the facilities of DICTUS, University of Sonora, Northwest México. Treatment with low protein diet (LP) consisted of a low protein input (diet with 250 g kg^?1 crude protein) through the culture period; treatment with high protein diet (HP) consisted of a high protein input (diet with 400 g kg^?1 crude protein) through the trial, and finally treatment VP consisted of an adjustment of protein input (diets with 250, 350 or 400 g kg^?1 crude protein), depending on the abundance of biota (zooplankton and benthos) in the system. Each species responded differently to the treatments. For blue shrimp, low protein input resulted in the lowest final body weight (12.9 ± 0.6 g) and biomass (696.0 g pool^?1). Survival and feed conversion ratio were similar in the three treatments. For white shrimp, the best growth, biomass and food conversion ratio were obtained in the low protein input treatment. Water quality parameters such as nitrate, ammonia and organic matter during the two trials, were better for LP and VP treatments. White shrimp seems to have lower protein requirements than blue shrimp. For the blue shrimp culture, adjusting protein input according to natural food abundance (zooplankton and benthos) in the system, seems to be advantageous because of the possibility of getting a production similar to that obtained with a high protein input through the farming period, but at lower feed cost, and with a lower environmental impact. It is concluded that a high protein input through the whole farming period is not the best feeding strategy for any of the two species.     

虾池水环境因子与虾病爆发的相关性分析

2001～2002年在对瓦房店市和庄河市等虾池水环境因子的连续监测中,运用多元分析研究了水环境因子与对虾病害爆发的相关性,主成分分析结果表明,NO3-N、COD、NO2-N、盐度、NH3-N和水温是显示对虾疾病爆发的关键因子。     

南美白对虾绿色养殖试验报告

本文报告了在不使用任何药物的基础上,采用环保型的“福寿牌”饲料、生物过滤池,有益微生物EM和PsB及科学的日常管理,南美白对虾经过75d的养殖,平均体长达10．3cm,平均体重达10．2G,每平方米水面平均产量0．668kg,饲料系数为0．9,投入产出比为1．253。     

Effect of promoted natural feed on the production,nutritional, and immunological parameters of Litopenaeus vannamei (Boone, 1931) semi‐intensively farmed

The effect of promoted biota on the production parameters, water quality, nutritional and immunological condition of Litopenaeus vannamei was assessed in semi‐intensive ponds. Earthen ponds were used as experimental units: three with formulated + natural promoted feed + shrimp (T1), three with formulated feed + shrimp (T2), and three with promoted natural feed without shrimp (Control). The dissolved oxygen (DO) levels were optimal for all treatments (≥6 mg L^?1) as well as the pH (8.4–8.6). Total ammonia nitrogen was greater in T2 (0.10 mg L^?1) than T1 (0.07 mg L^?1) and the Control (0.06 mg L^?1). Phytoplankton, zooplankton and benthos were more abundant in T1 and the Control. The promotion of natural feed had a positive effect on all the production parameters of shrimp with an increase of 19.0%, 3.5% and 23.9% in weight gain, survival, and final biomass, respectively; also it was observed a decrease of 13.9% in feed conversion ratio. No differences in haemolymph parameters were observed for nutritional indicators (glucose, cholesterol, proteins, and triglycerides) nor for immunological response (phenoloxidase and prophenoloxidase). The results indicate that the promotion of biotic communities enhances the production parameters of farmed shrimp, without affecting the nutritional and immunological status. Also the water quality was improved by the presence of biota.     

高效液相色谱法测定卤虫无节幼体中精胺含量

本研究建立了高效液相色谱法测定卤虫无节幼体中精胺含量的方法。样品经5％三氯乙酸溶液提取,提取液采用丹璜酰氯柱前衍生,以甲醇一水为流动相,经C18反相色谱柱分离后用紫外检测器检测。精胺的线性范围为0．1～1000μg/ml,线性相关系数为0．9999,检出限为0．06μg/ml。3个添加浓度（0。1、1．0和5.0μg/m1）的平均回收率为86．3％～96.39/6,相对标准偏差皆小于59/6。采用此方法对卤虫中精胺进行检测,其精胺含量为0．077mg/g。本方法具有分析时间短、线性范围宽、灵敏度和精密度高等优点,适合于卤虫中精胺的检测．     

养殖对虾新品种培育技术研究进展

本文介绍了国内外有关养殖对虾遗传改良研究的现状，并对选择育种、杂交育种、多倍体育种、人工雌核发育和转基因育种等手段研究进展进行了详细分析。提出利用现代生物学的新技术、新方法改造传统养殖业，将传统的育种研究技术与现代生物学技术相结合，加快培育优质、抗逆对虾养殖新品种是从根本上解决困扰对虾养殖业发展的重要研究方向。     

季铵盐类对对虾毒性和对弧菌杀灭效果的研究

国外及我国台湾等地普遍应用季铵盐类（ＢＫＣ）防治虾病,作者以国内生产的ＢＫＣ对斑节对虾Ｐｅｎａｅｕｓｍｏｎｏｄｏｎ、新对虾Ｍｅｔａｐｅｎａｅｕｓｓｐ．幼体及成虾的毒性和对弧菌的杀灭效果进行检测,以解决对虾养殖中药物的应用技术问题。实验表明,ＢＫＣ对斑节对虾各期幼体及成体的毒性存在着明显的差异,无节幼体对ＢＫＣ的敏感性特别高;弧菌及细菌对ＢＫＣ并不十分敏感,在２～３ｍｇ．Ｌ－１的浓度条件下才能杀灭水中７５％～９０％的弧菌。对成虾的细菌病,建议使用的ＢＫＣ浓度为０．５～１ｍｇ．Ｌ－１。     

野生及人工养殖的中国对虾（Penaeus Chinensis）的脂肪酸组成的分析及比较研究

通过对野生及人工养殖的中国对虾的肌肉、肝胰脏、性腺及卵的脂肪酸的分析比较，结果显示野生及人工养殖的中国对虾都含有大量的ω－３系列高度不饱和脂肪酸，这与其它海洋甲壳类的脂肪酸组成相类似；与野生的中国对虾相比较，人工养殖对虾的各组织及卵含有较高比例的亚油酸及较低比例的二十二碳六烯酸（ＤＨＡ）。野生与人工养殖的中国对虾在脂肪酸组成上的这一差异，是由于它们的生态环境及所摄食物的不同所造成的。从我们先前的实验证明ω－３系列和ω－６系列长链高度不饱和脂肪酸是中国对虾的必需脂肪酸，其中尤以ＤＨＡ最为重要，对于幼虾的生长及亲虾的成熟都是必需的。可见在人工养殖中国对虾的配饵中添加富含ＤＨＡ的脂肪源将是提高人工养殖对虾产量和质量的一个重要途径。     

The effects of variation in feed protein level on the culture of white shrimp, Litopenaeus vannamei (Boone) in low-water exchange experimental ponds

The present study was conducted to evaluate the effect of varying dietary protein level on pond water quality and production parameters of white shrimp Litopenaeus vannamei (Boone). Experimental units consisted of nine 400‐m² earthen ponds with a low water exchange. Two treatments were tested: treatment HP consisted of shrimp fed a high‐protein diet (40%) during the whole grow‐out, and treatment LP consisted of the use of a low‐protein diet for the complete farming period. No differences on any of the water quality parameters were observed among treatments. Excellent survival (over 85%) and feed conversion ratios (around 1.6), and acceptable growth (over 12 g) and biomass (from 1721 to 1793 kg ha^?1) were recorded in all experimental ponds. No significant differences in any of the production parameters were found among treatment groups.