不同形式钴对凡纳滨对虾生长和组织钴含量的影响

为研究氨基酸鳌合钴对凡纳滨对虾的营养效果．在凡纳滨对虾配合饲料中添加5、10、15mg／kg的氯化钴和蛋氨酸钴。饲养8周．4周末（饲养中期）称重．8周末称重并采集对虾肝胰脏和肌肉．测定肝胰脏和肌肉中的钴含量。结果表明：钴的添加形式和钴水平不影响对虾0～4周增重率．15mg／kg蛋氨酸钴显著提高了对虾0～8周增重率，且两种形式的钴之间差异显著（P〈0．05）。5、10mg／kg的蛋氨酸钴和5、10、15mg／kg的氯化钴不影响8周末对虾的增重率。特定生长率、饲料系数和蛋白质效率的变化趋势与增重率类似。钴的添加形式和钴水平不影响肌肉中的钴含量。15mg／kg的氯化钴组肝胰脏中钴含量显著高于对照组（P〈0．05）．其他各组间无显著差异；蛋氨酸钴各组肝胰脏中钴含量无显著差异；钴的添加形式不影响肝胰脏中钴含量。统计结果表明。促进生长方面，两种钴之间存在显著差异，蛋氨酸钴的营养效果好于氯化钴。饲料中蛋氨酸钴的添加量为15mg／kg时．对虾生长最快．5mg／kg时．可满足需要。     

植酸酶对凡纳滨对虾生长性能和体成分的影响

在凡纳滨对虾饲料中添加不同量微生物植酸酶(0,500,1000,2000 U/kg),观察虾的存活率、增重率、饲料系数及虾体和虾壳成分,研究饲料中添加植酸酶对凡纳滨对虾生长性能的影响。结果表明:饲养8周后,饲料中添加500~2000 U/kg植酸酶对凡纳滨对虾增重率、存活率和饲料利用无显著影响(P>0.05);植酸酶添加各组与对照组虾体的水分、粗蛋白、脂肪、灰分、总钙和总磷含量差异不显著;虾壳中粗灰分和钙含量在500和1000 U/kg组显著高于对照组和2000 U/kg组(P<0.05),虾壳磷含量在各饲料组间差异不显著。血清磷浓度在对照组和2000 U/kg组显著高于500 U/kg组(P<0.05),血清钙浓度在组间差异不显著,血清碱性磷酸酶活性以对照组最高,显著高于500和1000 U/kg组。结果说明,在特定试验条件下,饲料中添加植酸酶对凡纳滨对虾幼虾的虾壳和血清成分有显著影响(P<0.05),对幼虾生长性能影响不显著(P>0.05)。     

大黄对凡纳滨对虾生长和非特异性免疫指标的影响

在凡纳滨对虾饲料中分别添加大黄0、0.5、1.0、5.0、10.0和20.0g/kg,研究大黄对凡纳滨对虾(初始体重为0.34±0.004g)生长及非特异性免疫指标的影响。结果表明,大黄对凡纳滨对虾成活率、增重率、特定生长率、饲料系数、蛋白质效率和蛋白质累积率的影响不显著(P>0.05),对全虾和尾肌肉的灰分、脂肪和粗蛋白含量影响显著,全虾的粗蛋白和粗脂肪含量以1.0g/kg组最高(P<0.05),对凡纳滨对虾血清碱性磷酸酶、酸性磷酸酶、酚氧化酶、超氧化物歧化酶、溶菌酶以及血清总蛋白量等的影响显著,溶菌酶活性以1.0g/kg组最高(P<0.05);细菌感染实验中以1.0g/kg组存活率最高(P<0.05)。以非特异性免疫反应指标及感染实验存活率为指标,凡纳滨对虾饲料中大黄的适宜添加量为1.0g/kg。     

植酸酶对凡纳滨对虾生长性能和体成分的影响

在凡纳滨对虾饲料中添加不同量微生物植酸酶（0，500，1000，2000U／k），观察虾的存活率、增重率、饲料系数及虾体和虾壳成分，研究饲料中添加植酸酶对凡纳滨对虾生长性能的影响。结果表明：饲养8周后，饲料中添加500-2000U／kg植酸酶对凡纳滨对虾增重率、存活率和饲料利用元显著影响（P〉0．05）；植酸酶添加各组与对照组虾体的水分、粗蛋白、脂肪、灰分、总钙和总磷含量差异不显著；虾壳中粗灰分和钙含量在500和1000U／k组显著高于对照组和2000U／kg组（P〈0．05），虾壳磷含量在各饲料组间差异不显著。血清磷浓度在对照组和2000U／kg组显著高于500U／kg组（P〈0．05），血清钙浓度在组间差异不显著，血清碱性磷酸酶活性以对照组最高，显著高于500和1000U／kg组。结果说明，在特定试验条件下，饲料中添加植酸酶对凡纳滨对虾幼虾的虾壳和血清成分有显著影响（P〈0．05），对幼虾生长性能影响不显著（P〉0．05）。     

抗菌肽对凡纳滨对虾生长和机体免疫的影响

基础饲料(对照组)中添加10g/kg抗菌肽制剂喂养体重0.10±0.01g、体长2.17±0.11cm的凡纳滨对虾(Penaeus vannamei)30d,进行10d的水浴攻毒(鳗弧菌10~8/mL),探讨饲料中添加抗菌肽对凡纳滨虾生长、成活率、免疫保护率,以及肌肉中溶菌酶活性、超氧化物歧化酶活性、总抗氧化能力的影响。结果表明:饲料中添加抗菌肽可显著提高凡纳滨对虾相对增重率、成活率和对致病菌的免疫保护率(P<0.05),但对饲料系数无显著影响(P>0.05);未受外界微生物刺激时,饲料中添加抗菌肽对凡纳滨对虾总抗氧化能力有促进作用(P<0.05),受外界微生物刺激后,饲料中添加抗菌肽喂养凡纳滨对虾可提高对虾超氧化物歧化酶活性(P<0.05)和总抗氧化能力(P<0.01)。因此饲料中添加抗菌肽喂养凡纳滨对虾可提高其机体非特异性免疫。     

饲料中添加L-肉碱对牙鲆幼鱼生长、生化组成及血液指标的影响

研究0、300、600、900、1 200、1 500 mg/kg 6个L-肉碱添加水平对牙鲆(Paralichthys olivaceus)幼鱼生长、生化组成和血液指标的影响。结果表明:添加量为1 200 mg/kg的处理组牙鲆幼鱼的增重率和特定生长率显著提高,饲料系数显著降低(P<0.05);随着饲料中L-肉碱含量的增加,肝指数呈现下降趋势,且在添加量为900~1 500 mg/kg时,各组较对照组差异显著(P<0.05);饲料中添加L-肉碱显著降低各实验组脏体比(P<0.05),而对各处理组间存活率和肥满度均无影响(P<0.05);肌肉和肝脏中的脂肪含量与L-肉碱添加量呈负相关,当添加量为1 200~1 500 mg/kg时,较对照组差异显著(P<0.05);肌肉中的蛋白含量与L-肉碱添加量呈正相关,但各组差异不显著(P<0.05);饲料中添加L-肉碱降低血清中的谷草转氨酶、胆固醇、甘油三酯和尿素氮含量,且添加量1 200 mg/kg组各指标含量均显著低于对照组(P<0.05);各处理组的血糖含量较对照组均有所增加,其中1 200 mg/kg组血糖含量较对照组提高41.6%(P<0.05);血清中总蛋白和低密度脂蛋白均随着L-肉碱添加量的增加而呈下降趋势,高密度脂蛋白却得以提升,但差异均不显著(P<0.05)。分析认为,在本实验条件下,饲料中添加L-肉碱可促进牙鲆幼鱼生长,且降脂效果显著。建议L-肉碱最适添加量为1 200 mg/kg。     

斜带石斑鱼幼鱼对羟基蛋氨酸铜的需求

在斜带石斑鱼(Epinephelus coioides)幼鱼基础饲料(铜质量分数2.03 mg/kg)中分别添加6个水平的羟基蛋氨酸螯合铜(hydroxy methionine copper,HMC),制成铜质量分数分别为2.03、4.04、6.20、10.67、13.96 mg/kg的实验饲料,饲喂6周后,探讨HMC对幼鱼生长、非特异性免疫酶活性和组织铜沉积的影响,确定幼鱼饲料中铜的最适需要量。结果表明,饲料中添加HMC,对石斑鱼的增重率、特定生长率(SGR)和饲料系数等生长性能的影响有统计学意义(P0.05),以铜质量分数6.20 mg/kg组增重率和特定生长率最高,饲料系数最低,高于或低于2.03和13.96 mg/kg组,差异有统计学意义(P0.05),与4.04和10.67 mg/kg组差异无统计学意义(P0.05);但对成活率、肝体比影响差异无统计学意义(P0.05)。饲料中添加HMC对全鱼水分和粗蛋白含量影响无统计学意义(P0.05),对全鱼粗灰分和粗脂肪含量影响有统计学意义(P0.05)。石斑鱼血浆铜蓝蛋白(CP)的含量、血清和肝脏总超氧化物歧化酶(T-SOD)及铜锌超氧化物歧化酶(Cu-Zn-SOD)活性均以6.20 mg/kg组最高;饲料中铜的添加对血清谷胱甘肽过氧化物酶(GSH-Px)活性和肝脏硫代巴比妥酸反应物(TBARS)含量影响无统计学意义(P0.05)。与对照组相比,饲料中添加HMC均提高鱼体、肌肉和肝脏中铜含量,差异有统计学意义(P0.05),且以13.96 mg/kg组最高。饲料中添加适量的HMC可提高石斑鱼幼鱼的生长性能,提高抗氧化能力。在本实验条件下,以SGR为判据,通过二次回归方程拟合可得,以HMC为铜源,斜带石斑鱼幼鱼铜需要量为7.09 mg/kg。     

高蛋白棉粕替代鱼粉对凡纳滨对虾生长性能、非特异性免疫指标及抗病力的影响

【目的】研究高蛋白棉粕(High-protein cottonseed meal,HPCM)替代鱼粉对凡纳滨对虾幼虾生长性能、非特异性免疫酶活性及抗病力的影响。【方法】在基础饲料中分别添加质量分数0%、6.25%、9.375%、12.5%、18.75%的HPCM,分别替代饲料中质量分数0%、20%、30%、40%、50%和60%的鱼粉,配制6种等氮等能饲料,投喂初始体质量(0.38±0.01)g的健康凡纳滨对虾8周。【结果】HPCM替代鱼粉对凡纳滨对虾增重率、特定生长率、成活率、饲料系数及蛋白质效率影响均有统计学意义(P0.05),30%和40%替代组增重率和特定生长率最高,与对照组差异有统计学意义(P0.05),饲料系数最低,与对照组差异有统计学意义(P0.05),替代水平高于40%替代组时,蛋白质效率降低(P0.05);对凡纳滨对虾全虾体成分含量影响均有统计学意义(P0.05),随替代水平的增加,全虾中的水分、粗脂肪含量有升高趋势,粗蛋白含量呈先升后降趋势,粗灰分有降低趋势(P0.05);HPCM替代鱼粉对血清酚氧化酶(PO)、总超氧化物歧化酶(T-SOD)、碱性磷酸酶(AKP)、酸性磷酸酶(ACP)活性以及肝胰脏中丙二醛(MDA)含量影响有统计学意义(P0.05);攻毒试验表明,随着HPCM替代鱼粉比例及攻毒时间的增加,凡纳滨对虾存活率逐渐降低(P0.05)。【结论】以对虾增重率为判据,在鱼粉质量分数为25%的凡纳滨对虾基础饲料中HPCM替代鱼粉的适宜比例为37.44%。     

蜕壳素对凡纳滨对虾生长及表观消化率的影响

研究了外源性蜕皮激素对凡纳滨对虾生长和表观消化率的影响，实验时在基础饲料中分别添加0．1％、0．2％、0．4％的两种市售蜕壳素产品，制成6种外源性脱壳素配合饲料，不添加的基础饲料作为对照组，试验在260L玻璃钢循环水养殖系统中，每个剂量组设3个重复，8周生长试验结果表明：市售蜕壳素产品能有效地促进对虾生长，试验结束时，试验组虾体增重分别较对照组增加16．8％、7．52％、5．9％、11．4％、29．07％、16．53％，但是凡纳滨对虾对饲料粗蛋白的表观消化率没有明显地提高，凡纳滨对虾对脂肪的表观消化率较低。推算凡纳滨对虾饲料中最佳蜕皮酮添加量为60mg/kg。     

恩诺沙星在凡纳滨对虾体内的代谢和残留消除规律

在26±2℃水温下,每天投喂含有恩诺沙星药物的饲料,研究恩诺沙星在凡纳滨对虾Litopenaeus vanname肌肉、肠和肝胰脏组织中的代谢和残留消除规律。残留药物用乙腈提取,液相色谱串联质谱仪检测。结果表明:恩诺沙星在凡纳滨对虾体内可代谢为环丙沙星,对虾体内同时有恩诺沙星和环丙沙星两种药物残留;环丙沙星在肌肉、肝胰脏和肠组织中的消除时间分别为6、8、10 d,而恩诺沙星在这三组织中的消除时间则为12、14、16 d。建议把肠作为该药残留监控的靶组织,凡纳滨对虾的休药期不少于16 d。     

复方新诺明在罗氏沼虾中的药代动力学和组织分布

研究了单剂量肌肉注射给药[甲氧苄氨嘧啶(SMZ)0 60 mg/kg]、口灌给药[磺胺甲基异噁唑(SMZ)100 mg/kg]和复方口灌给药(SMZ 100 mg/kg和TMP 20 mg/kg)三种给药方式下,SMZ和TMP在罗氏沼虾中的代谢动力学,分析了SMZ和TMP血淋巴、肌肉和肝胰腺中的分布特征。结果表明,SMZ以肌肉注射方式给药后的血淋巴中,药物经时浓度曲线符合二室开放房室模型,而SMZ&TMP口灌给药后却不能用房室模型拟合。肌注给药后,SMZ的消除半衰期(t1/2β)为24.92 h,单方和复方口灌给药后SMZ的消除半衰期(t1/2β)分别为40.70和47.197 h。复方口灌给药后TMP的消除半衰期(t1/2β)为28.77 h,TMP对SMZ的药代动力学并无显著影响。口灌给药后,SMZ和TMP在肝胰腺中的药物浓度高于同时间肌肉中的药物浓度,但肌肉和肝胰腺中的SMZ消除速度基本一致。     

章丘地区土壤硒的含量分布及影响因素

以章丘地区土壤为对象,系统分析了表层、深层土壤及8条剖面土壤中Se元素的含量水平,研究了土壤中Se的分布特征及其与土壤类型、成土母质、地形地貌和土壤理化性质及组分的关系。结果表明：章丘地区表层土壤中Se含量在0.1～0.8mg/kg之间,以中硒土壤为主,富硒土壤面积173km2。土壤类型中,水稻土Se平均含量水平最高,为0.55mg/kg;成土母质中以石炭—二叠纪泥页岩发育的土壤Se含量最高;剖面土壤中的Se主要在表层富集。影响章丘地区土壤Se含量分布的主要因素是成土母质、地形地貌、土壤pH、有机质及土壤中硫、铁铝氧化物等组分。     

嗜酸小球菌对日本鳗鲡生长和免疫的影响

在饲料中分别添加3.0×108kg-1(A组)、1.5×108kg-1(B组)、1.0×108kg-1(C组)的嗜酸小球菌,制成3种实验饲料,以不添加嗜酸小球菌(D组)作为对照,饲养日本鳗鲡60d,以研究嗜酸小球菌对日本鳗鲡生长和免疫的影响。测定了增重率、饵料系数、成活率、血清中一氧化氮含量以及人工感染后的死亡率,并通过电镜观察了小肠壁细胞的微绒毛结构。结果表明A、B、C组和对照组的相对增重率分别为42.31%、75.42%、89.65%和40.32%,饲料系数分别为1.93、1.12、0.98和1.58,C组的相对增重率显著高于其他组,饵料系数则显著低于其他组,成活率也显著提高。电镜观察发现C组和B组的鳗鲡小肠细胞微绒毛排列整齐、细而长,吸收面积增大,从而提高了对饲料利用率,D组鳗鲡小肠细胞的微绒毛稀疏、短,排列不均匀。血清中NO的含量A、B、C组分别比对照组提高了23%、42%和73%。C组人工感染后的死亡率显著低于其他组。实验结果表明,在鳗鲡饲料中添加嗜酸小球菌可以显著促进鳗鲡的生长,降低饵料系数,增强其免疫力。     

Growth and antioxidant status of oriental river prawn <Emphasis Type="Italic">Macrobrachium nipponense</Emphasis> fed with diets containing vitamin E

A feeding trial was carried out to investigate the dietary vitamin E requirement of the oriental river prawn Macrobrachium nipponense (weight of 0.3–0.4 g) and its effect role on antioxidant activity. Prawns were fed with seven levels of vitamin E (0, 25, 50, 75, 100, 200, and 400 mg/kg diet) for 60 days. The results show that dietary vitamin E supplementation could significantly increased the prawn weight (P < 0.05). The activity of superoxide dismutase (SOD) in the hepatopancreas was significantly higher in prawns fed with diets supplemented with ≤75 mg/kg vitamin E than in those fed with diets supplemented with 100–400 mg/kg vitamin E (P < 0.05). The activity of catalase (CAT) in the hepatopancreas decreased significantly as dietary vitamin E supplementation increased (P < 0.05), and no significant difference was detected in glutathione peroxidase (GSH-Px) activity between different dietary groups (P >0.05). The contents of vitamin E in the hepatopancreas and in the muscle increased with increasing dietary vitamin E. There was a linear correlation between the vitamin E level in diet and that in muscle, and between the vitamin E level in diet and that in the hepatopancreas. All the above results indicated that dietary vitamin E can be stored in the hepatopancreas and muscle and lower both the activities of SOD and CAT in the hepatopancreas, suggesting that it is a potential antioxidant in M. nipponense. Broken line analysis conducted on the weight gains of prawns in each diet group showed that the dietary vitamin E requirement for maximum growth is 94.10 mg/kg.     

Effects of mercuric chloride on antioxidant system and DNA integrity of the crab Charybdis japonica

Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg²⁺) (at two final concentrations of 0.0025 and 0.0050 mg L⁻¹, prepared with HgCl₂) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg²⁺ dose and time in the hepatopancreas and a negative correlation with Hg²⁺ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg²⁺ in three tissues of C. japonica.     

Effect of dietary supplementation of vitamin C on growth,reactive oxygen species,and antioxidant enzyme activity of Apostichopus japonicus (Selenka) juveniles exposed to nitrite

Different amounts of vitamin C were added to diets fed to juveniles(2.5 ± 0.15 g) of sea cucumber Apostichopus japonic u s(Selenka) in an attempt to reduce the stress response of specimens exposed to nitrite stress. A commercial feed was used as the control diet and three experimental diets were made by supplementing 1 000, 1 500, or 2 000 mg vitamin C/kg diet to control diet separately in a 45-day experiment. Sea cucumbers were exposed to three different levels(0.5, 1.0, and 1.5 mg/L) of nitrite stress for 4, 8, and 12 h at four time intervals(0, 15, 30, and 45 d). Growth of the animals was recorded during the experiment. Reactive oxygen species(ROS)(i.e. hydroxyl free radical(-OH), malondialdehyde(MDA) and total antioxidant capacity(T-AOC)) and antioxidant enzyme activities(i.e., superoxide dismutase(SOD) and catalase(CAT)) were measured. Response surface methodology(RSM) was used to analyze the effect of multiple factors on ROS indices and enzyme activities. Weight gain(WG) and special growth rate(SGR) of vitamin C supplementation groups were significantly higher than those of control group( P 0.05). The levels of-OH and MDA increased under exposure time extending and nitrite concentration increasing, whereas T-AOC level decreased. SOD and CAT activities increased at 4 h and 8 h and decreased at 12 h. During the days in which the animal consumed experimental diets, the levels of-OH and MDA decreased and that of T-AOC increased. This result suggests that diets containing vitamin C could reduce the nitrite stress response in the animals and increase their antioxidant capacity. The multifactor regression equation of growth performance, ROS indices, and duration of feeding results suggest that vitamin C supplementation of 1 400–2 000 mg/kg diet for 29–35 days could reduce effectively the effects of nitrite exposure.     

Effect of copper on the growth of shrimps Litopenaeus vannamei: water parameters and copper budget in a recirculating system

Shrimps( Litopenaeus vannamei) were intensively cultured in a recirculating aquaculture system for 98 days to investigate effects of 0.3 mg/L Cu on its performance, Cu budget, and Cu distribution. Shrimps in Cu-treated systems had greater mean final weight(11.10 vs 10.50 g), body length(107.23 vs 106.42 mm), survival rate(67.80% vs 66.40%), and yield(6.42 vs 5.99 kg/m 3), and lower feed conversion ratio(1.20 vs 1.29) than those in control systems but the differences were not significant. Vibrio numbers remained stable(10 4 –10 6 colony forming units/mL) in the rearing tanks of both control and treated systems. Total ammonium-N, nitrite-N, nitrate-N, pH, chemical oxygen demand, 5-day carbonaceous biochemical oxygen demand, and total suspended solids were similar in controls and treatments. Dissolved Cu concentration in the treated systems decreased from 0.284 to 0.089 mg/L while in the control systems it increased from 0.006 2 to 0.018 mg/L. The main sources of Cu in the treated systems were the artificially added component(75.7% of total input), shrimp feed(21.0%), water(2.06%), and shrimp biomass(1.22%). The major outputs of Cu occurred via the mechanical filter(41.7%), water renewal(15.6%), and draining of the sediment trap(15.1%). The foam fractionator removed only 0.69% of total Cu input. Harvested shrimp biomass accounted for 11.68% of Cu input. The Cu concentration of shrimps in the Cu-treated systems(30.70 mg/kg wet weight) was significantly higher than that in control systems(22.02 mg/kg). Both were below the maximum permissible concentration(50 mg/kg) for Cu in seafood for human consumption in China. Therefore, recirculating systems can be used for commercial on-growing of Litopenaeus vannamei without loss of shrimp quality, even in water polluted by 0.30 mg/L Cu. The mechanical filter is the main route for Cu removal.