Juvenile Pacific White Shrimp Research Articles

Effect of dietary macro-algae in diet of juvenile Pacific white shrimp Litopenaeus vannamei

An 8-week feeding trial was conducted to evaluate the effect of dietary macro-algae in diet of juvenile Pacific white shrimp, Litopenaeus vannamei. The five macro-algae ingredients, including Saccharina japonica, Porphyra dioica, Gracilariopsis lemaneiformis, Ulva lactuca, and Undaria pinnatifida, were used for test diets, named SJD, PDD, GLD, ULD, and UPD, respectively. A reference diet (RD) and five test diets (30% test ingredients and 70% RD) were formulated. Each diet was randomly assigned to triplicate groups of 40 shrimp (initial body weight, 2.00 ± 0.01 g) and the shrimp were hand fed four times a day to apparent satiation. During the last 2 weeks, the fecal samples were collected by siphoning. The results showed that among five test diets, shrimp fed the SJD had the highest weight gain and the lowest feed coefficient, shrimp fed the SJD and GLD shared the same survival ratio and were significantly higher than shrimp fed the PDD and UPD (p < 0.05). For the composition of whole body, shrimp fed the SJD had the highest protein and lipid content compared with the shrimp fed other test diets. Apparent dry matter digestibility from high to low was: P. dioica, S. japonica, G. lemaneiformis, U. lactuca, and U. pinnatifida. Apparent protein digestibility of five macro-algae was highest in U. pinnatifida and lowest in G. lemaneiformis. Additionally, the highest apparent digestibility of gross energy was found in P. dioica. Apparent digestibility of total phosphorous in five ingredients was generally low and highest in S. japonica which was significantly higher than other ingredients (p < 0.05). These results indicated that S. japonica is more suitable for feed ingredient than other four kinds of macro-algae.

Evaluation of a fish meal analogue as a replacement for fish meal in practical diets for Pacific white shrimp Litopenaeus vannamei

Three six-week growth trials and a digestibility trial were conducted to evaluate a fish meal analogue (FMA) as a replacement for fish meal (FM) in shrimp feeds. Trials 1 and 2 evaluated and confirmed the potential of FMA supplementation (0, 48.5, 97, 145.5 and 194 g/kg) as a replacement for FM up to 200 g/kg without balancing for phosphorus (P) in practical diets for juvenile Pacific white shrimp L. vannamei. At the end of trial 1, shrimp offered diets containing 48.5 g/kg FMA exhibited significantly higher weight gain (WG) than those fed with the diet containing 145.5 g/kg FMA. At the end of trial 2, dietary FMA inclusion at 48.5 and 97 g/kg significantly improved WG and protein retention (PR), while reducing FCR and protein content of shrimp body compared to the diet containing 194 g/kg FMA. To determine whether P deficiency is the cause of reduced growth, the third trial was conducted utilizing equivalent diet but balanced for P. At the end of trial 3, shrimp fed diet containing 48.5 g/kg FMA+P showed significantly higher WG and PR than those fed diet containing 145.5 g/kg FMA+P. No decreasing trend of growth was detected in the diets containing FMA compared to the FM-based diet. Apparent digestibility coefficients of dry matter, energy, protein and amino acids of FMA were determined using chromic oxide as an inert maker and the 70:30 replacement technique. The energy, protein and individual amino acid digestibility of FMA were significantly lower than those of soybean meal and FM which were run at the same time. Results of this work indicate that FMA can replace up to 200 g/kg FM in shrimp diets with supplemental inorganic P. Given the good growth across the range of inclusion without any indication of a growth depression, the low nutrient digestibility of FMA may be due to an atypical response or the product simply does not work with the testing technique.

Chlorella vulgarismeal improved growth performance, digestive enzyme activities, fatty acid composition and tolerance of hypoxia and ammonia stress in juvenile Pacific white shrimpLitopenaeus vannamei

<i>Chlorella vulgaris</i>meal improved growth performance, digestive enzyme activities, fatty acid composition and tolerance of hypoxia and ammonia stress in juvenile Pacific white shrimp<i>Litopenaeus vannamei</i>

Effects of Dietary Lactobacillus plantarum on Growth Performance, Digestive Enzymes and Gut Morphology of Litopenaeus vannamei

A 15-day feeding trial was conducted to investigate the effect of dietary Lactobacillus plantarum on growth performance, digestive enzyme activities and gut morphology of juvenile Pacific white shrimp, Litopenaeus vannamei (initial body weight=7.96±0.59g). Four microbound diets were formulated to contain fermentation supernatant (FS), live bacteria (LB), dead bacteria (DB), and cell-free extract (CE) of L. plantarum. Results indicated that final weight was significantly higher in FS, DB, and CE group in comparison to the control group (P<0.05). The maximum weight gain rate (WGR) and specific growth rate (SGR) of the CE diet group were significantly higher than that of other groups (P<0.05). The FCR of CE diet group was lower than that of the control, LB, DB, and FS diets groups (P<0.05). The highest digestive enzyme activities (amylase, lipase, and pepsin activity) in the hepatopancreas and gut of shrimp were observed in the CE diet group. Histological study revealed that dietary CE diet could significantly increase the enterocytes height of shrimp. The administration of cell-free extract of L. plantarum could effectively improve the growth performance of L. vannamei via the improvement of digestive enzyme activities and the enterocytes height of shrimp. The results of this study will be essential to promote application of probiotics in shrimp aquaculture.

Evaluation of dried fermented biomass as a feed ingredient in plant-based practical diets for juvenile Pacific white shrimp Litopenaeus vannamei

Two growth trials were designed to evaluate the utilization of dried fermented biomass (DFB) in commercial type feed formulation for Pacific white shrimp, Litopenaeus vannamei. In trial 1, four experimental diets were formulated to utilize increasing levels (0, 25, 50 and 100 g/kg) of spray-dried fermented biomass (SDFB) as a replacement of fish meal (FM). Results indicated that SDFB can be utilized up to 50 g/kg as a substitution for FM without causing growth depression in shrimp. However, dietary SDFB supplementation at 100 g/kg significantly reduced the weight gain (WG) of shrimp and increased feed conversion ratio (FCR). This reduction in performance is likely due to palatability or nutrient imbalances of the feed. In trial 2, nine experimental diets were formulated with increasing levels (0, 20, 40, 60 and 120 g/kg) of spray-dried (S) or granular (G) DFB to replace soy protein concentrate (SPC) or SPC + corn protein concentrate (CPC). This allowed the comparison between spray-dried and ring-dried products. Ring drying produced a granular product, reducing dust and increasing product particle size. Shrimp fed with diet containing 20 g/kg GDFB performed the best in terms of final mean weight, WG and FCR. Significantly reduced growth and increased FCR were observed in shrimp fed diets containing 60 and 120 g/kg SDFB. Lipid content of whole body was significantly reduced when GDFB was incorporated at 120 g/kg. No significant differences were detected in survival, protein retention efficiency as well as protein and ash contents of the whole shrimp. Results from analysis of covariance indicated that the processing method (covariant) had a significant effect on final mean weight, WG and FCR. In general, shrimp fed with diet containing granular product performed better as compared to those fed with diets utilizing spray-dried product. GDFB can be utilized in the diets up to 120 g/kg in practical shrimp feeds as a substitute for SPC and CPC without compromising the growth of shrimp. However, a significant reduction in WG was observed in the diets containing 60 and 120 g/kg SDFB. The results in the current study demonstrate that processing changes to produce a granular product produced an improved feed ingredient for shrimp.

Growth of Pacific White Shrimp Fed Diets Containing a Mixture of Soybean Meal and Tuna Silage

AbstractThis study evaluated the use of tuna by‐product silage (TBS) in diets based on soybean meal (SBM) for the Pacific white shrimp Litopenaeus vannamei. A diet based on fish meal (FM, positive control) only was compared with five isonitrogenous formulations (35% crude protein) based on SBM containing increasing dietary levels of TBS (0, 14.9, 29.8, 44.7, or 59.6%) replacing 0% (TBS0, negative control), 25% (TBS25), 50% (TBS50), 75% (TBS75), or 100% (TBS100), respectively, of the protein derived from SBM. A diet containing tuna by‐product meal (TBM) as the sole protein source and one using a commercial feed as reference were also included. Each diet was tested on shrimp in triplicate over 41 d using 70‐L fiberglass tanks in a closed recirculating system. Each tank was stocked with 10 juvenile shrimp (mean initial weight, 1.09 g). Shrimp fed diet TBS25 grew as well as those fed diets with 100% of the protein from FM. The growth differences were mainly attributable to differences in the nutritional quality of diets. Whole‐body composition was significantly affected by diet. The broken‐line regression model using thermal growth coefficient data allowed us estimate that the maximum inclusion level of TBS in shrimp fed the SBM‐based diet was 26.31%. To reduce the cost of shrimp feed, the ratio of 75% SBM and 25% TBS proteins seems to be the best formulation for juvenile Pacific white shrimp diets.

Effects of various levels of dietary copper supplementation with copper sulfate and copper hydroxychloride on Pacific white shrimp Litopenaeus vannamei performance and microbial communities

A 42–day trial was conducted to evaluate the performance of juvenile (0.30g initial weight) Pacific white shrimp Litopenaeus vannamei offered diets containing various levels of copper hydroxychloride (Cu2(OH)3Cl) containing 58.8% copper (Cu) or Cu sulfate (CuSO4) containing 25.5% Cu. The basal diet (360g/kg protein, 80g/kg lipid) was primarily composed of soybean meal, fish meal, corn protein isolate and whole wheat and was formulated to be deficient in Cu (approximately 10mgCu/kg). The basal diet (B10) was supplemented with 30, 90, 150, and 210mgCu/kg from each Cu source. With the exception of 1 treatment (H220, Cu supplemented diet with dietary copper 210mg/kg from Cu hydroxychloride, n=4), five replicate groups of 15 shrimp per tank (initial weight 0.30g) were offered the test diets in slight excess. At the end of the trial, no significant differences were observed in final biomass (53.20–64.40g), final mean weight (4.34–4.87g), weight gain (1349–1544%), feed conversion ratio (FCR, 1.61–1.82), survival (81.3–96.0%), and thermal growth coefficient (0.082–0.087). The carapace, hepatopancreas, and whole shrimp Cu were significantly increased with dietary Cu levels from either source. No significant differences in hemolymph Cu contents were observed between the two sources. The Cu concentrations of hepatopancreas and whole shrimp were significantly lower in shrimp fed diets with Cu hydroxychloride than those in shrimp fed diets with Cu sulfate. The Cu contents of final whole body significantly increased with dietary Cu levels from either source and corresponded to a decreased trend in whole body Cu retention as dietary Cu increased regardless of source. Sequencing of intestinal and fecal microbiomes (16S V1–V3) captured distinct microbial communities based on source but not copper treatment group. However, the abundance of several specific family and genera of bacteria did appear to respond to different types and doses of dietary copper. Among these we observed a trend of decreased abundance of particular species of Vibrios, including V. harveyi, V. sinaloensis and V. orientalis. Results of this study confirm that both copper sources are utilized efficaciously by Pacific white shrimp, however, differential deposition patterns indicated the two sources of Cu are metabolized differently. Hence, additional studies to assess the specific metabolic pathways of various Cu sources as well as possible effects of high copper levels on resistance to infection should be undertaken in the future. Statement of relevanceIn this study, we assessed the efficacy of various levels of dietary copper supplementation with copper sulfate and copper hydroxychloride in Pacific white shrimp. Our finding shows that both copper sources are utilized efficaciously but metabolized differently by shrimp. This manuscript provides valuable information about effects of high copper levels from two copper sources in shrimp.

Effect ofl-ascorbyl-2-polyphosphate supplementation on growth performance, body composition, antioxidative capacity and salinity stress tolerance of juvenile Pacific white shrimp,Litopenaeus vannamei

An 8-week feeding trial was conducted to evaluate the effects of ascorbic acid (AsA), in the form of l-ascorbyl-2-polyphosphate (LAPP) on growth performance, body composition, antioxidative capacity and salinity stress tolerance of juvenile Pacific white shrimp, Litopenaeus vannamei. Five practical diets (46% crude protein and 7.6% lipid) supplemented with graded levels of AsA (14.64, 48.55, 84.98, 308.36 and 639.27 mg kg−1 diet) were fed to five replicate groups of L. vannamei (mean initial wet weight 0.57 g). No significant differences were found on growth performance among all treatments. However, whole body lipid content significantly decreased with dietary AsA levels increasing. Activities of total antioxidant capacity, glutathione reductase and glutathione peroxidase were significantly affected by dietary AsA levels. Shrimp fed LAPP-free diet had higher malondialdehyde content than those fed the diets supplemented with LAPP. Dietary AsA levels higher than 308.36 mg kg−1 diet increased the survival of shrimps after 1, 2 and 3 h of acute salinity change. Broken-line regression analysis on survival after 3 h of salinity stress and second-degree polynomial regression analysis on glutathione reductase data indicated that the optimal dietary AsA requirement of L. vannamei was estimated to be 306.39, 319.75 mg kg−1 diet respectively.

Evaluation of black soldier fly (Hermetia illucens) larvae meal as partial or total replacement of marine fish meal in practical diets for Pacific white shrimp (Litopenaeus vannamei)

Black soldier fly larvae (BSFL) meal, produced from the larvae of Hermetia illucens, has shown promise as a fish meal (FM) replacement in diets for rainbow trout, catfish and tilapia, but has not been examined as an alternative protein source in shrimp diets. Six isonitrogenous (35% crude protein, as fed) and isoenergetic (16.7kJ available energy g−1 of diet) diets containing graded levels of BSFL as replacements for protein from menhaden FM were fed to juvenile (1.24g±0.01; mean±SE) Pacific white shrimp, Litopenaeus vannamei. Diet 1 (the control) was formulated similar to a commercial shrimp diet containing 25% menhaden FM and 23% soybean meal. Diets 2–6 were formulated as a dose-response series that progressively replaced protein from menhaden FM with BSFL meal at inclusion rates of 7%, 14%, 21%, 28%, and 36% of diet; this equated to progressively replacing 16.5% of dietary protein provided by menhaden FM. Diets were fed to juvenile shrimp stocked into eighteen 110-L saltwater aquaria (30ppt) (three replicates per dietary treatment) at a density of 15 shrimp per aquarium (50/m2) for 63days. Nonlinear and spline regression analysis of responses indicated that the maximum level of BSFL meal inclusion varied significantly with the response being modeled. Generally, without modification of the ingredient or replacement diet nutrient profiles, 95% to 100% of most growth responses, i.e., shrimp final weight, weight gain, specific growth rate, and food conversion, could be obtained if replacement of FM by BSFL meal was limited to <25% of the diet, depending on performance measure. Similarly, 95% or greater of maximum whole-body protein and lipid content could be achieved when BSFL inclusion was restricted to <29% and 15%, respectively. Comparison of amino acid profiles in the test diets with recent requirement estimates for limiting amino acids in BSFL meal also suggest future strategies for increasing dietary substitution of FM with BSFL.

Evaluation of flash dried yeast as a nutritional supplement in plant-based practical diets for Pacific white shrimp Litopenaeus vannamei

Growth and digestibility trials were conducted to evaluate the use of flash dried yeast (FDY) as a supplement in practical shrimp feeds. The six-week growth trial evaluated the effects of FDY supplementation (0, 10, 20, 40 and 60 g kg–1) in the plant-based practical diet on the performances and proximate compositions of juvenile Pacific white shrimp, Litopenaeus vannamei. Final biomass, final mean weight, per cent weight gain (WG), feed conversion (FCR) and protein retention efficiency (PRE) of Pacific white shrimp were not significantly influenced when FDY was added up to 40 g kg–1 of the diet. However, 60 g kg–1 FDY supplementation significantly reduced growth, feed utilization and protein retention. Supplementation of FDY in the practical diets of Pacific white shrimp did not affect protein, moisture, lipid, crude fibre, and ash content of whole shrimp body. Apparent digestibility coefficients of energy, protein, and amino acid (AA) for FDY were determined using chromic oxide as an inert marker and the 70:30 replacement technique. The energy and protein digestibility of FDY were 38.20% and 53.47%, respectively, which were significantly lower than fishmeal (FM) and soybean meal (SBM) that were run at the same time. Most amino acid digestibility of FDY was lowest among the three ingredients tested. Results of this work indicated that energy, protein and amino acid digestibility of FDY are lower compared to SBM and FM, and high levels supplementation (≥60 g kg–1) of FDY can cause negative effects to the growth response of Pacific white shrimp. Based on these results, further research regarding the effects of the low level inclusion of FDY in practical diets on immune responses of Pacific white shrimp is warranted.

Green Water Meal as Protein and Carotenoid Sources in Grow-out Diets for Pacific White Shrimp, Litopenaeus vannamei

The present study was conducted to evaluate the potential of green water meal (GWM) as an alternative dietary ingredient for juvenile Pacific white shrimp, Litopenaeus vannamei. Five isoproteic and isolipidic diets were formulated with 0% (GWM0, control diet), 10% (GWM10), 20% (GWM20), 30% (GWM30) and 40% (GWM40) of GWM replacing fishmeal protein and fed five times daily to triplicate groups of shrimp with an average initial weight of 6.42±0.02 g. In general, growth performance and feed utilization of shrimp fed with GWM10 did not show any significant differences with the control diet. Survival rate was above 88% and not affected by the dietary treatments. The whole-body protein and lipid of the shrimps decreased with the increasing GWM level in the diets. The shrimps fed with the GWM-based diets (GWM10, GWM20, GWM30 and GWM40) presented more intense red/orange colour and contained higher total carotenoid concentration compare with the control diet. The present findings suggested that GWM is an excellent source of carotenoid for shrimp pigmentation and able to replace fishmeal protein at up to 10% replacement level.

Dietary tryptophan requirements of juvenile pacific white shrimp, Litopenaeus vannamei (Boone) reared in low-salinity water

An 8-week growth trial was designed to study the effect of dietary tryptophan on juvenile Pacific white shrimp Litopenaeus vannamei (Boone) in low-salinity water (0.50–0.80 g L−1). Six diets with different concentration of l-tryptophan (2.61, 3.11, 3.61, 4.11, 4.61 and 5.11 g kg−1 dry diet, defined as diet T1, T2, T3,T4, T5 and T6, respectively) were randomly assigned to triplicate groups of 30 shrimps (0.43 ± 0.005 g). The results indicated that 3.61 g kg−1 dietary tryptophan (diet T3) treatment gained the maximum weight gain, the highest protein efficiency ratio and body protein deposition, the relative muscle weight, and the lowest feed conversion ratio, hepatosomatic index, haemolymph urea nitrogen concentration and AST and ALT activities (P < 0.05). The polynomial regression calculated using weight gain, feed conversion ratio and body protein deposition indicated that the optimal dietary tryptophan requirement for L. vannamei reared in low-salinity water was 3.65–3.95 g kg−1 tryptophan of dry diet, correspondingly 8.90–9.63 g kg−1 of dietary protein. To identify the mechanism underlying tryptophan requirement, haemolymph metabolites with different treatments were analysed. The results revealed that lack or excess dietary tryptophan led to significant different metabolite profiles.

In vitro prediction of digestible protein content of marine microalgae (Nannochloropsis granulata) meals for Pacific white shrimp (Litopenaeus vannamei) and rainbow trout (Oncorhynchus mykiss)

Digestible protein (DP) contents of novel feed ingredients are required for test diet formulation and commercial feed production. Species-specific in vitro pH-Stat protein hydrolysis was used to predict the DP contents of three algal meals produced from a common lot of the marine eustigmatophyte microalga, Nannochloropsis granulata, for juvenile Pacific white shrimp (Litopenaeus vannamei) and rainbow trout (Oncorhynchus mykiss). Protein degree of hydrolysis (DH) and predicted protein apparent digestibility coefficients (ADCs) for Pacific white shrimp were statistically similar for all meals with average DH of 2.09% (P=0.052) and predicted ADC of 74.6% (P=0.053). Alternatively, meals processed by supercritical fluid extraction at 70 and 90°C showed significantly (P<0.001) higher DH and predicted ADC than the untreated base material for rainbow trout with average DH of 4.79% and predicted ADC of 87.0%, compared to 2.53% and 79.1%, respectively. Predicted protein ADC for all N. granulata meals was moderate for Pacific white shrimp (69–78%) and high for rainbow trout (79–88%) and therefore indicates their potential for use in fish and shrimp diets. Based on our results, we suggest DP values (dry matter basis) for similar N. granulata meals of 26% for Pacific white shrimp and 29% for rainbow trout.

Effects of dietary phytase supplementation on growth performance and apparent digestibility coefficients of Pacific White ShrimpLitopenaeus vannamei

A growth trial and a digestibility trial were conducted to evaluate the efficacy of phytase supplemented to practical shrimp feeds. The 5 weeks growth trial evaluated the effects of phytase supplementation in replete phosphorus (P) diets on the performances and compositions of juvenile Pacific white shrimp, Litopenaeus vannamei. No significant differences were observed in final biomass, final mean weight, weight gain, feed conversion ratio (FCR), protein retention and survival across all the treatments. Shrimp reared on the P deficient diet had significantly higher P retention and lower whole body P levels as compared to shrimp fed the other diets. Copper content in the whole shrimp body was significantly increased in the treatment supplemented with 1,000 IU kg−1 feed phytase. The digestibility trial was conducted to study the combined effects of phytase supplementation levels and diet type (plant-based versus fishmeal-based) on apparent digestibility coefficients of Pacific white shrimp, Litopenaeus vannamei. There were no effects of diet type so the data was combined. Phytase incorporation at both 500 and 2,000 IU kg−1 significantly improved protein digestibility, whereas P digestibility was enhanced when 2,000 IU kg−1 phytase was supplemented to the diet. Apparent digestibility coefficients of alanine, arginine, aspartic acid, cysteine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tyrosine and valine were significantly increased when fed diets contained 500 and 2,000 IU kg−1 phytase supplementation. Results of this work demonstrate that under the conditions of the study growth was not enhanced by phytase supplementation in P replete diets. However, nutrient retention for Cu and digestibility of P, protein and a number of amino acids were enhanced.

Partial replacement of fish-meal by soy protein concentrate and soybean meal based protein blend for juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to evaluate the effect of fish-meal replacement on growth performance, whole body composition, apparent digestibility coefficients and anti-oxidative ability of juvenile Pacific white shrimp, Litopenaeus vannamei. Five practical diets were formulated to contain graded levels (5, 10, 15, 20 and 25%) of fish-meal. Soy protein concentrate and soybean meal based protein blend was used to replace fish-meal, amino acids were supplemented in the low fish-meal diet to get similar amino acid profile as the high fish-meal diet. Weight gain, survival, feed conversion rate (FCR), feed intake and protein efficiency ratio (PER) did not show any significant differences between any of the groups. Alanine ratio in whole body were higher in shrimp fed high fish-meal diets while arginine decreased with the increasing fish-meal levels. The Fe content in whole body was significantly lower in shrimp fed the low fish-meal diets, while the other minerals showed no difference among all the groups. Apparent digestibility coefficients (ADC) of dry matter, protein, Ca, P, Cu, Zn and Mg were equal in all the treatments, while ADC of Fe decreased with the decreasing fish-meal levels. When dietary fish-meal decreased, the anti-oxidant related enzymes activity (Total antioxidant capacity (T-AOC) and Catalase (CAT)). Superoxide dismutase (SOD) was unaffected by treatments. Nitric oxide (NO) contents in hemolymph significantly decreased with the decreasing fish-meal levels, while Phenoloxidase (PO) was unaffected. The results indicated that growth performance and apparent digestibility coefficients of nutrients were not affected when fish-meal was replaced from 25% to 5%, but anti-oxidative ability and immune response were damaged after fish-meal level decreased to 15%. Statement of relevanceThe results of this manuscript contribute to the commercial feed industry of white shrimp, it will be helpful in fish meal replacement, which is very important to the sustainable development of aquaculture.

Some Limiting Factors in Superintensive Production of Juvenile Pacific White Shrimp, Litopenaeus vannamei, in No‐water‐exchange, Biofloc‐dominated Systems

AbstractSuperintensive shrimp culture in zero‐exchange, biofloc‐dominated production systems is more biosecure and sustainable than traditional shrimp farming practices. However, successful application of this technology depends upon optimizing dietary formulations, controlling Vibrio outbreaks, and managing accumulative changes in water quality and composition. A 49‐d study investigated the effect of two commercial feeds of differing protein content and an indoor limited‐exchange, biofloc‐dominated culture environment on Litopenaeus vannamei performance and tissue composition, water quality and ionic composition, and Vibrio dynamics. Juveniles (5.3 g) were stocked at 457/m3 into four 40 m3 shallow raceways containing biofloc‐dominated water and fed one of two commercial feeds with differing protein content, 35 or 40%. Shrimp performance, Vibrio populations, and changes in shrimp and culture water composition were monitored. There were no significant differences (P &gt; 0.05) in shrimp performance (survival, weight, growth, specific growth rate, total biomass, yield, feed conversion ratio, and protein efficiency ratio) or proximate composition between feed types. The 40% protein feed resulted in higher culture water nitrate and phosphate concentrations, alkalinity consumption and bicarbonate use, and higher phytoplankton density. The presence of Vibrio, specifically Vibrio parahaemolyticus, reduced shrimp survival. This survival decrease corresponded with increased culture water Vibrio concentrations. Culture water K+ and Mg2+ increased significantly (P &lt; 0.05), and Sr2+, Br−, and Cl− decreased significantly (P &lt; 0.05) over time. While Cu2+ and Zn2+ did increase in shrimp tissue, no heavy metals accumulated to problematic levels in culture water or shrimp tissue. These results demonstrate the importance of monitoring Vibrio populations and ionic composition in limited‐exchange shrimp culture systems.

Efficacy of inorganic and chelated trace minerals (Cu, Zn and Mn) premix sources in Pacific white shrimp, Litopenaeus vannamei (Boone) fed plant protein based diets

The present experiment was conducted to evaluate the efficacy of trace minerals (Cu, Zn and Mn) premixes from inorganic and chelated (chelated to 2-hydroxy-4-methylthiobutanoic acid or hydroxy analog of methionine; Mintrex™) sources, in juvenile Pacific white shrimp, (Litopenaeus vannamei) fed plant protein based practical diets. Eight experimental diets comprising a trace minerals (Cu, Zn and Mn) deficient Basal control, and diets supplemented with the trace mineral premixes at four different levels of 2.5 (M2.5), 5 (M5), 7.5 (M7.5) and 8.5g/kg (M8.5) from chelated source and at three different levels of 5 (I5), 8.5 (I8.5) and 20g/kg (I20) from inorganic source were formulated. Eleven numbers of juvenile shrimp averaging 0.6±0.01g (mean±SD) were fed one of the eight experimental diets in triplicate groups for 8weeks. At the end of the feeding trial, shrimp fed M2.5 and I8.5 diets exhibited the similar final weight (FW) and weight gain (WG) (P<0.05). Performance for Cu and Zn content in the hepatopancreas tissues and whole body showed equal efficiency of M5 compared to I8.5 diet (P<0.05). Whereas, nonspecific enzyme, CuZn super oxide dismutase (CuZn SOD) from the serum and hepatopancreas tissue was recorded to be peaked for the group of shrimp fed M5 diet. Moreover, plasma protein and glucose levels were recorded to be similar between the groups of shrimp fed M2.5 and I20 diets (P<0.05). Therefore, the present experiment demonstrated, a higher efficiency of chelated over inorganic source of trace mineral premix in Pacific white shrimp, (L. vannamei) fed plant protein based diets. Statement of relevanceThe significance of trace mineral bioavailability has become more important as the composition of majority of commercial fish feed has been changing and there is an increased use of dietary plant protein. As a result, the bioavailability of trace minerals is being adversely affected by the presence of antagonistic factor such as phytic acid in plant protein. Even though, our knowledge in fish nutrition has advanced significantly, the information on trace minerals requirement is still limited and fragmentary. Inorganic form (sulfate/nitrate) of trace mineral has traditionally been used in aquafeed formulation. However, the limited bioavailability of inorganic source of trace mineral due to its higher affinity to antinutrients has hastened the search for alternative form of inorganic trace minerals. Overall performance observed in the present experiments vouched the potential benefit of using chelated trace mineral, Cu, Zn & Mn premix in marine shrimp, Pacific white shrimp to promote the optimum growth, trace minerals saturation in shrimp body and tissue as well as to ensure the optimum enzyme activity and health of cultured shrimp. The present experiment opens a new avenue to compare the efficacy of inorganic and chelated source of trace minerals in other commercially important marine and fresh water fish species.Whereas, the sustainability issue has put a new dimension in aquafeed formulation with a wide array of new ingredients and additives, on the other hand, the importance of basic nutrient such as trace minerals is still in sideline. Substantial investment and integrated scientific efforts are warranted to bridge the knowledge gap and further improve our understandings on the significance of dietary trace mineral in fish nutrition and health at the least cost to environment.

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

AbstractGrain 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.

Digestibility of Glandless Cottonseed Protein in Diets for Pacific White Shrimp, Litopenaeus vannamei

ABSTRACTAccurate digestibility coefficients for protein, energy, and lipid are needed by feed formulators to optimize diets to meet nutritional requirements and to substitute ingredients cost‐effectively. Of particular interest is protein, which accounts for the majority of shrimp feed content and expense. The current study evaluated seven cottonseed meal and protein products. Most of the samples were derived from a glandless cotton variety that lacks significant levels of the antinutritive compound, gossypol. The various protein fractions were evaluated for apparent crude protein, crude lipid, and energy digestibility when fed to juvenile Pacific White Shrimp, Litopenaeus vannamei. Apparent energy digestibility for the protein fractions derived from the glandless seed ranged from 76.7% for ground kernels to 94.6% for protein isolate, and these values were greater than the value obtained for the commercial meal that contained gossypol (64%). Apparent protein digestibility for the six glandless‐cotton‐based samples varied from 72.3% for the ground full‐fat kernels to 94.1% for the protein isolate, and these values were mostly higher than the value obtained for the commercial meal (82.3%). The high apparent digestibility values demonstrate that low‐gossypol cottonseed protein products may be useful as a cost‐effective replacement for more expensive protein sources in L. vannamei diets.

Effect of cadmium-polluted diet on growth, salinity stress, hepatotoxicity of juvenile Pacific white shrimp (Litopenaeus vannamei): Protective effect of Zn(II)–curcumin

Cadmium (Cd) is one of the major transitional metals that have toxic effects on aquatic organisms. To investigate the effects of dietary cadmium on growth, salinity stress, hepatotoxicity in juvenile Pacific white shrimp (L. vannamei) and potential protective effect of Zn(II)–curcumin, five experimental diets (control, 100mg/kg Zn(II)–curcumin, 30mg/kg Cd, 30mg/kg Cd+100mg/kg Zn(II)–curcumin, 30mg/kg Cd+200mg/kg Zn(II)–curcumin) were formulated. The results showed that Cd at 30mg/kg induced significant increase in weight gain, specific growth rate and visible alterations to the hepatopancreas structures of L. vannamei. Compared with control diet, 100mg/kg Zn(II)–curcumin added diet had no effect on growth performance or feed utilization, while healthier hepatopancreas and less plasma ALT, AST production was found. Moreover, 200mg/kg dietary Zn(II)–curcumin significantly ameliorated the Cd induced hepatotoxicity while 100mg/kg dietary Zn(II)–curcumin slightly ameliorated. Cd accumulation in the whole body was decreasing and Metallothioneins like was increasing in hepatopancreas with increasing dietary Zn(II)–curcumin level. The shrimp fed with dietary Zn(II)–curcumin showed higher survival rate after acute salinity change. Therefore, it can be demonstrated that hepatotoxicity and hormesis could be induced by Cd when Cd levels were 30mg/kg, Zn(II)–curcumin could mitigate the effects of dietary Cd on L. vannamei.