Production Methods and Resource Use at Litopenaeus vannamei and Penaeus monodon Farms in India Compared with Previous Findings from Thailand and Vietnam

Shrimp farms in India had average yields (pond surface basis) of 7.86 ± 1.04 (SE) m.t./ha/yr for Litopenaeus vannamei (n = 89) and 3.88 m.t./ha/yr for Penaeus monodon (n = 11). Average feed conversion ratio was 1.48 ± 0.04 for L. vannamei and 1.24 ± 0.12 for P. monodon. Land use for production ponds, supporting area, and feed ingredients averaged 0.634 ± 0.053 ha/m.t. for L. vannamei and 0.716 ± 0.087 ha/m.t. for P. monodon. Saline water volume used at farms without water exchange was 18,522 ± 4065 m³/m.t. for L. vannamei and 9528 m³/m.t. for P. monodon. Farms exchanging water used 149,188 m³/m.t. for L. vannamei and 191,500 m³/m.t. for P. monodon. Freshwater embodied in feed was 1678 ± 508 m³/m.t. for L. vannamei and 1401 ± 137 m³/m.t. for P. monodon. Average energy use for farm construction and repair, farm operations, and embodied in feed and liming materials was 82.14 ± 9.08 GJ/m.t. for L. vannamei and 59.03 ± 24.92 GJ/m.t. for P. monodon. Wildfish used to make fishmeal included in feed was 1209 kg/m.t. for L. vannamei and 1611 kg/m.t. for P. monodon. Farm infrastructure, pond management methods, yields, and resource use in India were similar to those previously reported for shrimp farms in Thailand and Vietnam.     

Moult cycle of laboratory-raised Penaeus (Litopenaeus) vannamei and P. monodon

This study was carried out to gather quantitative data on the moult cycle and stages in laboratory-raised shrimp, kept at a constant temperature of 27°C. The stages of the moult cycle were differentiated and characterised by microscopic analysis of cuticle, epidermis and moulting processes in the uropods of P. vannamei and P. monodon. Five major moult stages were defined: early- and late post-moult (A and B), inter-moult (C) and early- and late pre-moult (D1 and D2). Total moult cycle duration was around 5 and 6.5 days for 2-g P. vannamei and P. monodon and 11 and 12 days for 15-g P. vannamei and P. monodon, respectively. Overall, the relative duration of the moult stages within the cycle was 5–10% for A, 9–16% for B, 12–20% for C, 28–36% for D1 and 30–38% for D2 stage. It was concluded from this study that the pre-moult stages comprised the dominant phase of the cycle and that P. monodon moulted at a significantly slower rate than P. vannamei, under the given conditions. Without the use of invasive techniques, the moult process was charted in laboratory-raised shrimp in Europe, providing a tool for taking into account this important physiological factor in further experiments.     

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.     

南美蓝对虾和南美白对虾混养试验

南美蓝对虾 ( Penaeus stylirostris)原产于拉丁美洲太平洋沿岸水域 ,它具有生长速度快、适应盐度范围广、人工繁殖较南美白对虾容易、抗病毒能力较强 ,易于集约化饲养等优点。 2 0 0 1年 4～ 5月 ,福建省漳州市出现了大规模的南美白对虾流行性虾病 ,其中海水养殖的南美白对虾发病率达60 %以上 ,兑淡养殖的南美白对虾发病率也在30 %以上 ,严重制约对虾养殖业的发展。为了探索南美蓝对虾的兑淡养殖技术 ,我场于今年 6月 5日开始进行南美蓝对虾和南美白对虾混养试验 ,并取得较好的经济效益 ,平均单产为 2 34kg/1 0 0 0 m2。一、池塘条件利用…     

Nitrogen and Phosphorus Dynamics in the Biofloc Production of the Pacific White Shrimp,Litopenaeus vannamei

A study evaluating nitrogen and phosphorus dynamics was carried out using biofloc technology (BFT) systems employed to raise Litopenaeus vannamei juveniles. The study was carried out for 42 d in three fiberglass tanks with 210 L useful volume with no water exchange. Salinity, temperature, dissolved oxygen, pH, nutrients, suspended solids, and chlorophyll‐a were monitored every 3 d. At the completion of the experiment, the shrimp had absorbed 39.1 and 35.0% of the total nitrogen (N) and phosphorus (P) inputs, respectively, while 39.0% of the N and 34.1% of the P remained in the system in dissolved forms. The dominant process of ammonium immobilization in the system was oxidation by nitrifying bacteria. On Day 42, the nitrate concentration represented more than 80% of the total dissolved inorganic nitrogen in all tanks. However, most of the dissolved nitrogen present in the tanks (80%) was organic. Phosphate and organic nitrogen and phosphorus continuously accumulated in the system throughout the experiment. The removal of these nutrients should be the focus of future studies because they may enhance the growth of harmful algae in tanks and in the water bodies that collect the post‐crop wastewater.     

南美白对虾池塘海水养殖稳产高效技术

近两年来,南美白对虾以生长快、饵料系数低、适盐广、规格整齐、单位产量高等优良特性已在全国沿海乃至内陆等许多地区养殖并推广开来。笔者2001年在海南省文昌市翁田镇养殖南美白对虾,该镇上半年南美白对虾单产最高的达2000kg/亩(1亩=667m~2)以上,一般的养殖户正常的养殖单产平均也达1000kg/亩左右,经济效益十分显著,但下半年整个海南省南美白对虾病害开始流行,几乎每家养殖场无一幸免地发生虾病,有     

Production of Tiger Shrimp (Penaeus monodon) in Potassium Supplemented Inland Saline Sub-Surface Water

Abstract

Potassium deficient inland saline (10 g L^?1 salinity) well water was supplemented with muriate of potash to achieve 50% (57 mg L^?1) and 100% (114 mg L^?1) of seawater potassium concentration and used for the production of tiger shrimp (Penaeus monodon). Total mortality was observed in non-supplemented water within 6 days compared to 88.0% survival in K⁺100% and 85.3% survival in K⁺50% up to 60 days. P. monodon were subsequently cultured for 110 days in two identical 0.25-ha ponds supplied with water of 10 g L^?1 and supplemented with the potassium equivalent of 35% of seawater. Survival and production were 55.8% to 64.25% and 157.70 kg (630.8 kg ha^?1) to 172.75 kg (691 kg ha^?1), respectively.     

Growout of Pacific White Shrimp, Litopenaeus vannamei, Stocked into Production Ponds at Three Different Ages

This study was designed to determine the production characteristics of the Pacific white shrimp, Litopenaeus vannamei, stocked into grow‐out ponds at three different sizes and ages. To meet this goal, three groups of postlarvae (PL) were obtained. The first group was placed in a nursery system for 21 d (N21), the second for 14 d (N14), and the third was stocked directly into ponds (DS). Shrimp from each nursery treatment (three tanks per treatment) were pooled and then subdivided for stocking into four replicate 0.1 ha ponds per treatment, another four ponds were stocked directly (DS) with PL₈. All 12 ponds were stocked on the same day at a density of approximately 35 PL/m², and cultured over a 16‐wk period and then drain harvested. After harvest, mean average weights (15.4, 16.9, and 14.9 g), survivals (63, 62, and 64%), FCRs (2.7, 2.5, and 2.7), and average yields (3592, 4005, and 3374 kg/ha) were determined for N21, N14, and DS, respectively. No significant (P > 0.05) differences were observed among treatments. Regardless of nursing time, nursed juveniles did not differ significantly in production characteristics from shrimp stocked directly from the hatchery.     

渔业简讯

南美白对虾养殖业是上海市奉贤区的一大优势产业,但受气候条件的影响,虾类在上海的养殖期只有半年,从而造成虾产品主要集中在8、9月份上市.     

南美白对虾养殖技术

南美白对虾原分布于西太平洋沿岸,是北美和中南美洲的重要养殖虾类之一,也是世界上养殖产量最高的虾类之一。我国南方省份近年来引进该品种养殖取得较好的经济效益。该虾甲壳薄、出肉率高,具有适应性强、抗病性好、个体大、生长快、离水存活时间长、养殖周期短等特点。霞     

南美白对虾含肉率及肌肉营养价值的评定

取52尾南美白对虾作样品，测定其含肉率和肌肉的营养成分，得出的结果是：含肉率为53.53％；肌肉（干样）中含粗蛋白90.97%，粗脂肪1.22%，粗灰分6.41%，无氮浸出物1.40%，钙151.79mg/100g，磷1406.75mg/100g；水解氨基酸总量为83.21%，必需氨基酸含量31.86%，游离氨基酸总量9133.18mg/100g，必需氨基酸指数47.79%。南美白对虾是一种营养价值较高的虾类，具有良好的养殖开发前景。     

Delivery of Bioencapsulated Oxytetracycline to the Marine Shrimp Penaeus monodon

Abstract Post larvae of shrimp Penaeus monodon were fed Artemia sp. enriched with oxytetracycline (OTC). The amounts of this antibiotic in the Artemia sp., the shrimp, and the water of the experimental system were measured by radial diffusion bioassay. The results indicated that 11% of the OTC was taken up by the Artemia sp. After 8 d of being fed OTC-enriched Artemia sp., the shrimp were found to contain 3.12 μg OTC/shrimp, which is twelve times greater than the average minimum inhibitory concentration (MIC) cited in the literature for sensitive strains of Vibrio spp. The recommended therapeutic dose for treatment of bacterial infections is four times the MIC.     

Use of Grain Distillers Dried Yeast in Practical Diets for Juvenile Pacific White Shrimp,Litopenaeus vannamei

Grain distillers dried yeast (GDDY) is a yeast‐based protein source that is obtained from the bioethanol industry. A range of yeast‐based products has been evaluated as nutritional supplements in fish diets, yet there is limited information in shrimp. Therefore, the objective of this study was to evaluate the production response of Litopenaeus vannamei fed diets containing increasing levels of GDDY in two growth trials. In trial 1, five diets formulated to contain 360 g/kg crude protein, 80 g/kg lipids, and up to 300 g GDDY/kg were evaluated under laboratory conditions with juvenile shrimp (1.90 ± 0.10 g, initial weight). In trial 2, juvenile shrimp (0.40 ± 0.01 g, initial weight) were fed similar diets where lysine was supplemented in diets with high levels of GDDY (200 and 300 g/kg of diet). The results from this study demonstrate that inclusion of GDDY up to 300 g/kg of diet did not cause negative effects on final biomass, mean final weight, feed conversion ratio, and survival. Furthermore, the addition of lysine to diets with high levels of GDDY (200 and 300 g/kg of diet) did not enhance growth performance under the reported conditions, confirming lysine was not limiting. Consequently, these results indicate that up to 300 g GDDY/kg of diet can be used in practical diets for L. vannamei in a clear water system.     

斑节对虾与凡纳对虾幼体对卤虫无节幼体摄食量的比较试验

用1000ml小水体进行斑节对虾和凡纳对虾各期幼体对卤虫无节幼体摄食量的比较实验，结果表明，二种对虾的卤虫摄食量与卤虫密度有关，在相同密度下，糠虾期凡纳对虾卤虫日摄食量明显高于斑节对虾，而卤虫密度对摄食量的影响凡纳对虾略低于斑节对虾，仔虾期卤虫摄食量差异日渐减小，P5-P6已很接近。     

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.     

Sperm Quality of Pond-Reared and Wild-Caught Penaeus monodon in Thailand1

Sperm quality, as determined by visual examination and by reaction with “egg-water” was not significantly different (P > 0.05) for sperm obtained by electro-ejaculation from ablated or non-ablated pond-reared Penaeus monodon. Nor was sperm quality different between pond-reared and wild-caught prawns. Normal sperm, determined by appearance, ranged from 17.1 to 21.0%, while reactive sperm ranged from 1.5 to 3.0%. There were, however, significant correlations (P < 0.01) between spermatophore weight and prawn weight (r= 0.73, N= 434). Male prawns weighing 4150 g produced on average spermatophores weighing 22.7 mg and containing 0.8 million sperm, while prawns weighing 61-90 g produced on average spermatophores weighing 56.6 mg with 2.5 million sperm. Ablation did not increase spermatophore size or sperm quality, although it significantly increased mortality of ablated males. Male prawns could be re-ejaculated at about weekly intervals with no change in sperm quality. Wild-caught female prawns artificially inseminated with spermatophores from electro-ejaculated males produced normal spawns with 51% average egg fertilization, and 41% nauplii hatch success. Nauplii hatch success following spawning increased from >60% for newly inseminated females to near zero after 30 days post-insemination, indicating spermatophore depletion and/or deteriorated sperm quality during spermatophore storage in the thelycum. The findings of the present study indicate that electro-ejaculation and artificial insemination are relatively simple and practical methods for improving captive reproduction performance of closed-thelycum prawns such as P. monodon, and that pond-reared and wild-caught males produced sperm of similar quality.     

南美白对虾育苗及淡化试验

南美白对虾为世界养殖产量最高的三大优良虾种之一,具有繁殖季节长,营养要求低,适应性强等特点。为开发南美白对虾的淡水池塘养殖,进行了南美白对虾的育苗及虾菌淡化试验。本试验在12．6m^3水体中投入120万尾南美白对虾无节幼体(N3)撞育至仔虾P5,经逐步淡化至P13,获淡化虾菌39．39万尾。单位水体产量3．13万尾,m^3,最高产量为4．28万尾/m^3,由N3至淡化虾菌P13成活率为32．8％,经14h运输,成活率为98．5％。     

斑节对虾性腺组织、细胞的原代培养条件优化

通过观察不同成分培养基及不同培养方法培养的斑节对虾性腺组织及细胞原代培养生长情况,分析细胞活力及生长相关基因表达情况,判断3种改良培养基的适用条件,为进一步细胞培养试验提供支持。试验结果表明,以L-15培养基为基础培养基,不同配方的培养效果差距较大,其中机械分离法可成功培养离体斑节对虾性腺组织,而酶解法与3号培养基结合效果较好;在培养过程中可见离体卵母细胞多呈悬浮生长,部分可见分裂相,离体精原细胞多呈贴壁生长,1号、2号培养基中的细胞可维持良好生长状态达一周以上;CCK测试结果表明,机械分离的性腺组织和酶解法分离的性腺细胞分别在1号、3号培养基中有更高的细胞活力,而2号培养基中的性腺组织及细胞在两种培养方法下的活力差别不大。进一步的荧光定量PCR检测了离体培养过程中MAPK信号通路相关基因的表达变化情况,结果表明,Ras、c-Mos、MEK1、ERK基因在卵母细胞中表达变化更显著,且c-Mos基因与离体细胞生长发育情况呈正相关。本试验系统性地筛选了适宜斑节对虾性腺组织、细胞的原代培养方法,为了解培养过程中的生理过程变化提供了相关参考数据。     

Use of Porcine Meal in Plant‐based Practical Diets for Pacific White Shrimp,Litopenaeus vannamei

Two growth trials were conducted to evaluate and confirm the efficacy of a porcine meal (PM) with high protein content (>90%) as an alternative feed ingredient in commercial‐type feed formulation for Pacific white shrimp, Litopenaeus vannamei. Six experimental diets were formulated for the two growth trials. The first five diets contained increasing levels (0, 1, 2, 4, and 6%) of PM as a replacement for soybean meal in a plant‐based diet with low inclusion level (6%) of fish meal (FM). The last experimental diet was produced utilizing 4.2% PM to completely replace FM. In Trial 1, shrimp (1.5 g initial mean weight, 20 shrimp/tank, n = 4) were offered test diets for 6 wk in a semirecirculation system. At the end of Trial 1, shrimp fed with the diet containing 6% PM exhibited significantly enhanced weight gain (WG), feed conversion ratio (FCR), and survival compared to those fed with the diet devoid of FM. As survival was poor across all treatments and different densities could mask growth results the trial was repeated. In Trial 2, shrimp (0.85 g, 15 shrimp/tank, n = 4) were offered diets for 6 wk. Dietary supplementation of PM at 6% significantly improved WG, FCR, and apparent net protein retention in contrast with the treatment devoid of FM, confirming the same trends in Trial 1. No significant difference was detected in protein, lipid, moisture, and mineral profiles of whole‐body shrimp as well as survival across all the treatments. Results of this study indicate that PM is a good high protein source in shrimp feeds, which can be included up to 6% in the low FM‐based diet without compromising the growth of shrimp.