中国对虾对Pb、Cr、Zn及其混合物的回避反应

利用“Ｙ”形回避槽,进行了中国对虾（ Ｐｅｎａｅｕｓ　ｃｈｉｎｅｎｓｉｓ） 对Ｐｂ 、Ｃｒ、Ｚｎ 及其混　合物的回避反应实验。计算得出中国对虾对Ｐｂ 、Ｃｒ、Ｚｎ 的５０ ％ 回避率浓度分别为１１ ．４、３３．２ 、和２３８．１ｍｇ／Ｌ。对虾对Ｐｂ － Ｃｒ 及Ｐｂ － Ｚｎ 混合液的回避反应呈相加作用,但当混合液浓度为０．５ 毒性单位Ｐｂ加０ ．５ 毒性单位Ｚｎ 时,回避反应呈协同作用。     

弧菌疫苗对斑节对虾和日本对虾免疫预防的作用

尝试使用免疫学的方法来防治对虾弧菌病。将病原副溶血弧菌制成福尔马林灭活疫苗,在实验条件下分别以浸泡、口服和注射等方式接种于斑节对虾和日本对虾,结果发现,在一定的范围内,对虾的免疫保护率随疫苗浓度的增加而升高。在注射接种的方式中,斑节对虾在１９＾９、１０＾８、１０＾７ｃｅｌｌｓ．ｍＬ＾－１的疫苗剂量下的保护力分别为４０％、５０％和４０％,浸泡组（疫苗浓度分别为１０＾８ｃｅｌｌｓ．ｍＬ＾－１、１０＾７     

斑节对虾幼体链壶菌病的防治试验

在斑节对虾无节幼体池前２～３小时用０．０１５～０．０２０ｍｇ／Ｌ浓度的亚甲基蓝或三氟乐灵作预防，１～２天后发现有链壶菌感染时再用０．０２０ｍｇ／Ｌ浓度的亚甲基蓝或０．０２０～０．０３０ｍｇ／浓度的三氟乐灵治疗。两种药物比较，三氟乐录能有效防治链壶菌病，其有效浓度为０．０２０～０．０５０ｍｇ／Ｌ；而亚甲基蓝在链壶菌感染不严重时才有效，若感染严重或无节幼体下池前未施药预防，待发病后再用药，治疗无效。     

副溶血弧菌对斑节对虾和日本对虾的致病力研究

作为条件致病菌的弧菌，前人对其致病性已作了大量的研究，但不同研究者得出的结果很不一致，有的甚至相互矛盾［1－4］，其差异主要在于浸泡感染能否使健康对虾致病。因此，本实验以不同的感染方式以及不同的实验条件，对斑节对虾体内分离出的副溶血弧菌的致病力进行研究，以便了解对虾弧菌病的发病条件。１材料与方法１.１材料 对虾：体长７～９ ｃｍ的健康斑节对虾（Ｐｅｎａｅｕｓ ｍｏｎｏｎｄｏｎ）和日本对虾（Ｐ．ｊａｐｏｎｉｃｕｓ），直接购于养殖场。 菌株：对虾病原菌一副溶血弧菌（Ｖｉｂｒｉｏ ｐｏｒａ－ｈａｅｍｏｌｙｔｉ…     

弧菌对斑节对虾虾苗致病性的研究

本文用6种弧菌对斑节对虾虾苗进行致病性试验。发现6种弧菌对各阶段幼和仔虾都有很强的致病作用。其中,对蚤状幼体致病性最强,其次是无节幼体、糠虾和仔虾。     

头孢氨苄对斑节对虾幼体发育及育苗水体细菌数量的影响

研究了不同浓度头孢氨苄(Cefalexin)对斑节对虾Penaeusmonodon幼体发育以及对斑节对虾育苗水体中异养菌总数和弧菌数量的影响。在试验初期,无论是对照组还是施用头孢氨苄的各试验组,育苗水体中的总异养菌数量和弧菌数量都呈现出较为明显的上升趋势;在第二次施用头孢氨苄后,各试验组的异养菌总数和弧菌数量的增幅明显低于对照组(或出现异养菌总数和弧菌数量缓慢下降),而对照组异养菌总数和弧菌数量则呈现显著的上升。施用0.5～1.0μL·L-1头孢氨苄对育苗水体中的总异养菌有显著的杀灭及抑制作用,但对弧菌数量杀灭及抑制作用并不显著;施用1.5μL·L-1头孢氨苄对育苗水体中的总异养菌和弧菌数量的杀灭及抑制作用显著。当幼体变态发育至仔虾第8天(P8)时,对照组异养菌总数和弧菌数量分别达6.33×105和3.55×104CFU·mL-1,均远远高于试验组的异养菌总数和弧菌数量增长的幅度。试验组的幼体变态到P1期的时间,比对照组缩短了10h以上;试验组的成苗率也比对照组提高了3.2%～13.1%。     

滩涂围垦养殖斑节对虾技术

斑节对虾（Ｐｅｎａｅｕｓｍｏｎｄｏｎ）俗称草虾 ,具有适盐范围广 ,耐低盐 ,生长快 ,个体大 ,耐干运能力强等特点 ,是我国海水虾类养殖的优良品种之一。目前斑节对虾的苗种繁育技术已经解决 ,成虾价格高而稳定。１９９９年笔者在防城港利用１．３３ｈｍ２ 塘 ,经过９４ｄ养殖 ,每６６７ｍ２ 产斑节虾１３２．４ｋｇ ,获得良好的经济效益。现将主要的养殖技术措施介绍如下。１池塘条件虾塘为滩涂围垦、三面环山、泥沙底质的池塘 ,蓄水塘 ,面积１．３３ｈｍ２ 左右 ,水深１．６ｍ以上 ,海水盐度１０‰～２２‰ ,溶氧在４．０ｍｇ／Ｌ以上 ,…     

非离子氨氮对罗氏沼虾幼体的毒性研究

通过非离子氨氮对罗氏沼虾幼体的急性致毒试验表明：Ⅴ期幼体９６ｈ的半致死浓度（ＬＣ５０）值为１．１４ｍｇ／Ｌ,安全浓度（ＳＣ）值为０．１１ｍｇ／Ｌ;Ⅸ期幼体９６ｈ的ＬＣ５０值为１．４０ｍｇ／Ｌ,ＳＣ值为０．１４ｍｇ／Ｌ,建议在育苗期间加强水质管理,有效地控制水体中非离子氨氮的浓度。     

斑节对虾杆状病毒的检测及感染率调查

本文报告了进境斑节对虾亲虾及其仔虾，成虾中的斑节对虾杆状病毒的包涵体和病毒颗粒的检测方法和病毒的感染率，检测结果显示，亲虾和虾苗的病毒感染率分别为２３．１％和６２．５％。     

墨吉对虾幼体耗氧量的初步研究

以墨吉对虾（ＰｅｎａｅｕｓｍｅｒｇｕｉｅｎｓｉｓＤｅｍｅｎ）为实验对象，测定其无节幼体至仔虾阶段的耗氧量，以及在ｐＨ值、盐度、氨氮浓度变动情况下幼体的耗氧量变化。实验结果显示，幼体各阶段（由Ｎ１～Ｐ１）耗氧量逐渐提高，且在Ｚ２期和Ｍ２期分别出现突跃点，相应递增率也加大。仔虾耗氧量在适宜的ｐＨ值、盐度及无氨氮的情况下呈稳定状态，高于或低于适宜范围耗氧量明显增加；而氨氮浓度由０～２ｍｇ／ｌ，仔虾的耗氧量变化先低后高，这是慢性中毒和死亡挣扎的表现。     

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.     

Studies on the Toxicity of Shrimp (Penaeus vannamei) Fed Diets Dosed with Aflatoxin B1 to Humans

Abstract

The objective of this study was to determine the potential for transmission of aflatoxin B₁ to humans through consumption of shrimp contaminated with this toxin. Pacific white shrimp (Penaeus vannamei) were fed diets dosed with three levels of afaltoxin B₁ (300, 400, and 900 ppb) in an 8 week indoor aquarium feeding trial. The shrimp were analyzed for residues of the toxin in the feces, whole shrimp and tail muscle after concentrating the aflatoxin by monoclonal antibody affinity chromatography, followed by radioimmunoassay. Aflatoxin B₁ was not detected in shrimp feces, whole shrimp or tail muscle within detection limits of 2 ppb. Our study suggests that the possibilities for aflatoxin B₁ toxicity occurring in humans via consumption of shrimp fed on diets contaminated with this toxin are limited.     

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.     

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。     

日本对虾虾苗对若干环境因子的适应性研究

我国日本对虾的养殖业发展历史并不长,有关日本对虾虾苗对环境因子适应性的研究报道较为有限。在育苗和养殖中,环境因子直接影响虾苗成活率和生产效益。为此,本文试图通过参考有限的相关资料,自己设计实验,在实验室利用人工模拟水域环境条件下,就日本对虾虾苗对若干环境因子(如光照强度、温度、盐度、溶解氧、pH值等)进行适应性研究,揭示其适应性规律,为日本对虾虾苗培育和养殖生产技术提供粗浅的参考依据。     

Tolerance of the shrimp Litopenaeus stylirostris, Stimpson 1894, to environmental stress: interindividual variability and selection potential for stress-resistant individuals

Our study showed that osmoregulatory capacity (OC) of shrimp from the same clutch displayed interindividual variability. When environmental salinity decreases, this variability increases. Thus, at isoosmotic point (sea‐water salinity ≈26), the coefficient of variation calculated for measured OC was 2.7%, whereas it was 8.2% for sea‐water salinity ≈1.5. In terms of haemolymph osmolality, the interindividual difference can reach up to 45.8% for the same water salinity level. The mean OC of individuals that have survived a series of salinity and temperature shocks is significantly greater than the mean value recorded within their original population. This increase in OC was maintained beyond the one or two moulting periods that these shrimp experienced during our experiment.     

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 dietary protein levels on growth of Penaeus stylirostris juveniles

The shrimp Penaeus stylirostris is currently produced on a commercial scale in Tahiti and New Caledonia. Both super-intensive (80 animals m⁻²) and semi intensive (25 m⁻²) systems are promoted. Locally produced commercial feed contains 380–400 g kg⁻¹ crude protein (CP) without special consideration for environmental impact. The need for a 'low pollution' diet implies reconsideration of the optimum dietary protein level for this species. Under experimental conditions, six isoenergetic practical diets ranging from 270 g kg⁻¹ to 440 g kg⁻¹ CP were formulated and fed to satiation for 30 days to juvenile P. stylirostris ; average growth rates were between 5.5 and 7.5 g per month with survival rates > 90%.
The lowest protein levels 270–310 g kg⁻¹, gave significantly ( P < 0.05) poorer growth (5.5 g per 30 days) than was observed with 330–430 g kg⁻¹ CP; 330 g kg⁻¹ CP may be recommended, and as it is lower than levels in diets used currently, there is a possibility of reducing nitrogenous waste. In addition to growth response, protein efficiency ratio, protein productive value and food conversion (feed/gain) all supported a recommended dietary protein level of 330 g kg⁻¹. Future prospects for practical feeds with even lower CP levels are considered.