凡纳滨对虾饲料添加剂的研究进展

凡纳滨对虾(Litopenaeus vannamei)俗称南美白对虾,是目前世界养殖产量最高的三大虾种之一,具有对水环境抗逆能力强、营养要求低、生长速度快,虾体含肉量大、肉质鲜美、营养丰富等诸多优点,自1998年来,在广东、广西、海南等省(区)广为     

Effect of Diet Size on Feeding Behavior and Growth of Pacific White Shrimp,Litopenaeus vannamei

Abstract

Six diet sizes, manufactured from crumbling large pellets, were investigated for their effect on the feeding behavior and growth of Pacific white shrimp, Litopenaeus vannamei. These diets containing 44.7% protein and 8.2% lipid were fed to 0.9 g shrimp for a period of eight weeks under indoor controlled laboratory conditions. Shrimp were stocked at a density of 12 animals per 52 L aquarium (50/m²) and were evaluated for feeding behavior, final weight, growth rate, feed conversion ratio (FCR), and survival. Feeding behavior was observed weekly starting at the beginning of the 4th week until the end of the trial. Results indicated that the variation in diet sizes did not produce significant differences in shrimp growth, FCR or survival. However, shrimp feeding behavior (in terms of total attacking incidents during feeding) was significantly different among diet sizes. This shrimp behavior was observed more frequently in aquaria fed larger diet size (3.0 mm pellet) as compared with those fed smaller diet sizes (0.7 mm and 1.2 mm crumbles). When shrimp were fed larger pellets, some of the individuals obstruct other individuals and monopolize the diet. Such “selfish” behavior of shrimp could result in considerable size variation and severe mortality of smaller individuals, which could be the case when shrimp are reared to market size. The effect of diet size on shrimp feeding behavior deserves further investigation and the use of a continuous monitoring device such as a video camera is strongly recommended. Future study should also consider various shrimp and pellet sizes more meaningful to aquaculture producers.     

Effects of Diet and Water Source on the Nursery Production of Pacific White Shrimp Litopenaeus vannamei

Penaeid shrimp reared in eutrophic pond water grow significantly faster than shrimp in clear well water, and this growth enhancement is especially pronounced in postlarval shrimp. The objective of this study was to determine if the nutritional benefits of pond water could supplement a lower protein feed for postlarval Pacific white shrimp Litopenaeus vannamei . Sixteen 230-L tanks were stocked with 10-d postlarvae at a density of 350 shrimp/tank. Four treatments (four replicates/treatment) were tested for 6 wk and consisted of: 1) shrimp grown in well water and fed a commercially available 45%-protein feed (W/45); 2) shrimp grown in pond water and fed the same 45%-protein feed (P/45); 3) shrimp grown in well water and fed a commercially available 52%-protein feed (W/ 52); and 4) shrimp grown in pond water and fed the same 52%-protein feed (P/52). At the end of the experiment. mean weight gain (± SE) for shrimp in pond water (1.85 ± 0.03 g) was significantly greater ( P > 0.0001) than shrimp in well water (0.98 ± 0.10 g). Mean weight gain for shrimp fed the 52%-protein feed (1.56 ± 0.13 g) was significantly greater ( P > 0.0001) than shrimp fed the 45%-protein feed (1.26 ± 0.20 g). In addition, there was a significant interaction effect between water source and feed ( P > 0.0001). Mean weight gain for shrimp in the W/52 treatment (1.23 ± 0.04 g) was 68% greater than shrimp in the W/45 treatment (0.73 ± 0.03 g). However, mean weight gain for shrimp in the P/52 treatment (1.90 ± 0.03 g) was only 5% greater than shrimp in the P/45 treatment (1.80 ± 0.04 g). These results suggest that organically rich pond water provides postlarval shrimp with sufficient nutrients to compensate for nutritional deficiencies associated with a lower protein feed.     

益生菌对凡纳滨对虾免疫功能及肠道菌群的影响

以类芽孢杆菌和双歧杆菌为益生菌,添加到凡纳滨对虾(平均体质量3.45g)的饲料中,饲养28d(水温25~27℃,盐度25~26,pH 7.8~8.1,溶解氧6mg/L),采用南京建成试剂盒和变性梯度凝胶电泳技术,研究益生菌对凡纳滨对虾免疫功能及肠道菌群的影响。结果表明,益生菌能够显著提高对虾血清过氧化物酶(对照组43.22U/mL,试验组76.33U/mL)、超氧化物歧化酶(对照组60.61U/mL,试验组101.18U/mL)、一氧化氮合酶(对照组7.54U/mL,试验组12.44U/mL)、酸性磷酸酶(对照组0.0446U/mL,试验组0.0574U/mL)和碱性磷酸酶(对照组0.0183U/mL,试验组0.0236U/mL)的活性(P0.01),明显改善对虾肠道的菌群组成,从而提高对虾抵抗疾病的能力。     

凡纳滨对虾感染白斑综合症病毒后的新症状

2007年6-7月,辽宁营口地区凡纳滨对虾养殖场陆续出现死虾现象,通过组织病理观察和PcR检测,确定为白斑综合症.患病初期,对虾并未表现出典型白斑、甲壳易剥离等症状,而在鳃区头胸甲内侧滋生一种囊状胶状物,导致头胸甲内侧肿胀,病理观察发现该滋生物为对虾感染白斑综合症病毒后,皮下组织"胶质化"的结果,同时胃和皮下组织的结缔组织中有大量的典型性病变核;细菌分离结果显示,伴随着弧菌和假单胞菌的混合感染.     

拟诺卡氏菌骨架对凡纳滨对虾生长及免疫功能的影响

将研究室分离纯化的卢森坦拟诺卡氏菌扩大培养,发酵液经过超声波破碎、离心、胰蛋白酶酶解、脱脂、冷冻干燥,得到白色细胞壁骨架。在基础饲料中添加0.1%和0.2%的拟诺卡氏菌细胞壁骨架,饲喂凡纳滨对虾幼虾[体质量(4.21±1.28) g],养殖周期为4周,测定各处理组对虾体质量,统计各组存活率,使用南京建成试剂盒测定对虾血淋巴和肝胰腺组织中的一氧化氮合酶、超氧化物歧化酶、酚氧化酶、溶菌酶、谷胱甘肽过氧化物酶活性及丙二醛的含量,佛波豆蔻酸乙酯法检测对虾血淋巴中呼吸爆发活性,采用副溶血弧菌对剩余对虾进行攻毒,统计对虾死亡率。试验结果显示,拟诺卡氏菌细胞壁骨架能够明显促进凡纳滨对虾的生长,显著提高对虾血淋巴和肝胰腺中的超氧化物歧化酶、一氧化氮合酶、酚氧化酶、溶菌酶、谷胱甘肽过氧化物酶的活性( P <0.05, P <0.01),显著降低丙二醛浓度( P < 0.01 ),显著增强对虾血淋巴的呼吸爆发活性( P <0.05, P <0.01),可提高对虾的免疫保护率,从而提高凡纳滨对虾的存活率。研究结果表明,拟诺卡氏菌细胞壁骨架的适宜添加量为0.1%。     

Effects of Artificial Substrate and Stocking Density on the Nursery Production of Pacific White Shrimp Litopenaeus vannamei

Nursery production may be enhanced by the addition of artificial substrate to increase the surface area upon which shrimp graze and to serve as refuge. The objective of this study was to assess the effects of the artificial substrate, AquaMats^TM, on the performance of postlarval Pacific white shrimp Litopenaeus vannamei stocked at three densities. Eighteen 230-L tanks were stocked with 10-d postlarvae (mean weight < 0.01 g). Six treatments were evaluated and consisted of shrimp stocked at three densities (778 shrimp/m², 1,167 shrimp/ m², and 1,556 shrimp/m²) with and without access to artificial substrate. Shrimp in all treatments received a commercial diet ad libitum . After 6 wk, shrimp were harvested from each nursery tank, counted, and batch weighed. Mean final weight, survival, production, feed conversion ratio, and water quality parameters were analyzed by 2-way ANOVA. There were highly significant ( P < 0.001) density and substrate effects on final weight, but there was no significant interaction effect. Final weight was 26.0, 17.4, and 34.5% greater in treatments with substrate than without substrate when stocked at 778, 1,167, and 1,556 shrimp/m², respectively. There was no significant density, substrate, or interaction effect on survival or water quality. Mean survival was ± 89.1% for all treatments. Increased shrimp growth in the presence of added substrate was likely due to the availability of attached particulate organic matter on the AquaMats^TM that served as an additional food source. Results from this study indicate that artificial substrate can be used to mitigate the potential negative effects of high stocking density on growth of L. vannamei in nursery systems.     

南美白对虾高位池养殖模式最适放养密度的调查

2003年1～6月,对海南琼山、文昌、万宁和三亚地区的51口高位虾池进行了跟踪调查。结果表明:放养密度与养殖周期、产量和饵料系数成正相关,其相关系数分别为:0.897、0.91和0.864。放养密度和饵料系数是影响养殖成本的两个主要因素,其关系可用线性回归方程:S=7.04 0.421X 1.209C来表示。高位池最适放养密度为210～255万尾/hm2。     

凡纳滨对虾α-淀粉酶基因的SNPs检测

利用PCR产物直接测序法,对凡纳滨对虾SPR和SPF 2个品种共40个样本的α-淀粉酶基因(GenBank序列号:AJ133526)的单核苷酸多态性(SNP)进行了研究。找到9个SNPs,分别为:C127T、A138G、T951C、T1083C、C1457T、A2147C、A2226G、A2297G和T2306C。其中1个SNP是第4外显子中的错义突变,2个SNPs分别是第5和第7外显子中的同义突变,6个SNPs是内含子中的突变。这些结果可为凡纳滨对虾的研究提供遗传学依据。     

Sperm Quality Over Consecutive Spermatophore Regenerations in the Pacific White Shrimp Litopenaeus vannamei

The reproductive potential of males plays an important role in the productivity of captive penaeids. Males present a large variability in their reproductive potential, and thus the selection of appropriate males for reproduction is highly desirable. The present study compares sperm quality at the beginning of the experiment (baseline values) with variations in sperm quality as a result of consecutive spermatophore regenerations. This was done to evaluate possible predictive criteria for optimal sperm quality based on morphological and biochemical criteria in pond-reared Pacific white shrimp Litopenaeus vannamei males. Sperm quality was similar between left and right spermatophore. Sperm count and proportion of normal sperm increased by 86 and 65% (P < 0.05) respectively, from baseline values to third spermatophore regeneration. Proportion of dead sperm progressively decreased with consecutive regenerations, attaining values 33% lower by the third regeneration, compared to baseline values. This indicates that no decrease in sperm quality occurs in L. vannamei during consecutive regenerations and that the existing spermatophores at stocking of males should be expelled to have higher sperm quality in regenerated spermatophores. Furthermore, this procedure allows selecting individuals with high baseline sperm quality based on significant correlations between baseline and regenerated sperm quality observed in the present work. Baseline values of glucose concentration in the hemolymph were positively correlated to baseline values of sperm count (r = 03, P < 0.05). In contrast, baseline values of several lipids in the hemolymph were negatively correlated to several traits of sperm quality at first sampling (baseline values) or at first regeneration. These results are discussed in terms of nutritional requirements of males and of possible predictive criteria of sperm quality.     

凡纳滨对虾消化液对4种饲料蛋白质的酶解研究

用离体消化方法研究了凡纳滨对虾胃、肝胰脏和肠道的粗酶液对鱼粉、豆粕、菜粕和花生粕酶解8 h的体外消化率及0～4 h 4种饲料蛋白质酶解液中氨基酸的生成量.试验结果表明,凡纳滨对虾胃、肝胰脏和肠道对鱼粉、豆粕、菜粕、花生粕的干物质和粗蛋白质总消化率分别为36.50%、50.78%、42.02%、39%和46.28%、56.45%、43.28%、60.40%;0～4 h,4种饲料酶解液的氨基酸生成量随时间变化的线性关系较好.对于同一原料,肝胰脏粗酶液的酶解速度最大,其他依次为肠道、胃粗酶液,表明肝胰脏对饲料蛋白质的酶解能力强于胃和肠;对于不同原料,以花生粕酶解氨基酸生成速度最大,其他依次为鱼粉、豆粕、菜粕,表明凡纳滨对虾对花生粕酶解消化的能力较强.饲料原料种类的差异和饲料蛋白质组成与性质的差异使其酶解氨基酸生成量和生成速度有差异.     

凡纳滨对虾白便综合征的组织病理学观察

本文比较观察了不同规格的健康和患白便综合征凡纳滨对虾Litopenaeus vannamei肝胰腺、中肠、后肠、后盲囊等的组织结构。组织病理显示:白便综合征凡纳滨对虾肠道严重病变,肠腔空,环肌两侧增生大量成纤维细胞,这些增生细胞取代了肠上皮,而不见正常柱状上皮细胞;肝胰腺有不同程度和性质的病变,如腺管萎缩、崩解、坏死等。凡纳滨对虾患白便综合征的组织病变演变过程为:最初肠上皮基膜下出现一圈增生细胞,肠上皮柱状细胞脱离基膜;增生细胞持续增生增多,肠上皮崩解脱落至肠腔,增生细胞完全取代肠上皮;增生细胞不断增生,增生细胞层逐渐变厚,随着时间的推移,增生细胞层近腔端的一圈增生细胞坏死,出现一圈棕黄色物质,最终坏死细胞连同棕黄色物质脱落至肠腔。脱落至肠腔的腺管细胞、上皮细胞、增生细胞排出体外即为肉眼可见的白便。     

不同种群凡纳滨对虾形态性状对体质量的影响

采用单因素方差分析、通径分析和多元回归分析等方法,比较取自美国塞班岛凡纳滨对虾养殖基地V101、OS、G24、NS 4个凡纳滨对虾种群的头胸甲长、第1~6腹节长、尾节长、体长、全长、头胸甲宽、第1~6腹节宽、头胸甲高、第1~6腹节高等24项形态性状和体质量(m)及其所有性状的比例参数,分析各群体形态差异以及主要形态性状对体质量的影响,并建立回归方程。试验结果表明,4个群体大部分形态差异显著(P0.05),V101和G2群体属于瘦长型,OS和NS属于高胖型。相关分析、通径分析、决定程度分析结果表明,V101群体头胸甲长和头胸甲高与体质量正相关,第2腹节高与体质量负相关;OS群体体长、第2腹节长、头胸甲宽与体质量正相关,第6腹节长与体质量负相关;NS群体头胸甲长、第6腹节高与体质量正相关,头胸甲宽与体质量负相关;G2群体头胸甲长、全长与体质量正相关,体长与体质量负相关。4个群体的多元回归方程经方差显著性检验均达到极显著水平(P0.01),且复相关指数均0.85,表明头胸甲部位在凡纳滨对虾良种选育中占重要地位。     

Inbreeding Effects on Hatchery and Growout Performance of Pacific White Shrimp, Penaeus (Litopenaeus) vannamei

In animal breeding programs, selection coupled with a narrow genetic base can cause high levels of inbreeding to occur rapidly (in one or two generations). Although the effects of inbreeding have been studied extensively in terrestrial animals and to a lesser extent in aquaculture species, little is known about the effects of inbreeding on penaeid shrimp. The objective of this study was to investigate the effects of inbreeding on hatchery and growout performance of the Pacific white shrimp, Penaeus vannamei. The experiment was conducted over 2 yr, and data from two successive generations (G₂ and G₃) of inbred (sibling–sibling mating) and outbred families were analyzed. There were 11 inbred and 12 outbred families in G₂ and 9 inbred and 10 outbred families in G₃. Inbreeding coefficients (F) for outbred and inbred families were 0.00 and 0.25, respectively, for G₂ and 0.00 and 0.375, respectively, for G₃. Growth rates for outbreds and inbreds were similar in both G₂ and G₃. Hatch rate for inbred families was 33.1% lower than for outbred families in G₂ and 47.1% lower in G₃. Inbreeding depression (IBD) (relative change in phenotype per 0.1 increase in F) ± 95% CI for hatch rate was ?12.3 ± 10.1%. Hatchery survival for inbred families was 31.4% lower than for outbred families in G₂ and 38.8% lower in G₃. IBD for hatchery survival was ?11.0 ± 5.7%. Growout survival was 1.9% lower for inbred families than for outbred families in G₂ and 19.6% lower in G₃. IBD for growout survival was ?3.8 ± 2.9%. There was also a significant linear relationship between IBD estimates for survival traits and mean outbred survival. At high outbred survival, IBD was low (e.g., growout survival in G₂), but IBD appeared to become more severe when outbred survival was lower. This suggests that stress (related to environment and/or life stage) may worsen IBD for survival traits. Results also indicate that moderate to high levels of inbreeding (>10%) should be avoided in commercial shrimp hatcheries because the cumulative effect of IBD on hatch rate and hatchery survival will significantly reduce postlarvae production. Thus, IBD can be significant enough to justify the use of inbreeding as a germplasm protection strategy (under certain scenarios) for genetic improvement programs.     

Effects of Dietary Carbohydrase Supplementation on Performance and Apparent Digestibility Coefficients in Pacific White Shrimp,Litopenaeus vannamei

A growth trial and a digestibility trial were conducted to evaluate the efficacy of carbohydrase supplemented to practical shrimp feeds. The 5‐wk growth trial investigated the effects of carbohydrase supplementation at 0, 0.01, 0.02, 0.03, 0.04, and 0.05% in soybean‐based diets on the performance of juvenile Pacific white shrimp, Litopenaeus vannamei. No significant differences were observed in final biomass, final mean weight, weight gain, feed conversion ratio, and survival across all treatments. The digestibility trial was conducted to evaluate the effects of carbohydrase supplementation at 0.02%, which is the recommended dose by the company that developed the carbohydrase on apparent digestibility coefficients of dry matter, protein, and energy of Pacific white shrimp. Protein digestibility was significantly improved when fed diets contained 0.02% carbohydrase in contrast with the basal diet. No significant differences were found in apparent digestibility coefficients of dry matter and energy. Based on the positive results on protein digestibility, further research regarding the efficacy of exogenous enzymes and their application is warranted.     

三种对虾病毒在浙江省凡纳滨对虾中的流行性调查研究

对虾白斑综合症病毒、桃拉综合症病毒及传染性皮下与造血组织坏死病病毒是目前威胁对虾养殖业较为严重的3种病毒.分别从浙江省6个凡纳滨对虾的主养殖区随机采样对虾699尾,通过PCR检测对虾的病毒携带情况.检测结果显示,6个养殖地区传染性皮下造血组织坏死病病毒检测结果均呈阳性,总阳性率达100％;萧山、舟山、象山养殖场的对虾白斑综合症病毒检测结果有阳性,总阳性率为5.58％;6个养殖场均未检测出桃拉综合症病毒.表明浙江省凡纳滨对虾养殖区域的桃拉综合症病毒得到了有效控制,传染性皮下造血组织坏死病病毒和对虾白班综合症病毒有较高的感染率,而且存在混合感染的情况.