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1.
Four commercial solvent‐extracted oilseed meals/cakes, viz. soybean meal (SBM), groundnut oil cake (GNC), rapeseed meal (RSM) and sunflower oil cake (SFC), were fermented with fungus Aspergillus niger, and its effect on apparent digestibility coefficient (ADC) was studied in Penaeus vannamei. Reference diet and eight experimental diets containing 700 g/kg reference diet and 300 g/kg test ingredient with 5 g/kg chromic oxide were formulated. Each diet was randomly allotted to three tanks containing ten shrimps. Shrimps were adapted to the experimental diets for a week, and faeces were collected using Falcon tube from second week onwards. The ADC of all the ingredients significantly (p < .05) increased with fermentation and the increase being higher in SBM (78.46%–91.71%) for dry matter and in SFC (71.51%–87.02%) for protein. Analysis of variance showed that the ADC of both dry matter and protein significantly (p < .05) differed in treatments (p = <.001) and ingredients (p = <.001). The average ADC of ingredients was ranked as SBM > GNC > RSM > SFC. The most digestible essential amino acid (EAA) in fermented ingredients was methionine in SBM, arginine in GNC, valine in RSM and histidine in SFC. A better improvement in amino acid digestibility was observed in fermented SFC. Results indicated that P. vannamei efficiently digests fermented ingredients compared to unfermented ones.  相似文献   

2.
The anaesthetic effects of eugenol on Penaeus monodon were investigated at the different eugenol concentrations (60, 110, 160 and 210 mg/L), water temperature (21, 26 and 31°C), air exposure time (3, 6, 9 and 12 min) and body weight (2.62 ± 0.27, 6.34 ± 0.36 and 11.43 ± 0.33 g). The anaesthesia and recovery time were recorded. The results showed that the anaesthesia time of the shrimp decreased with the increase in the eugenol concentration and water temperature, and the recovery time increased with the increase of the eugenol concentration and the decrease of water temperature. Under the same eugenol concentrations, the recovery time increased with the increase of air exposure time and body weight. Under the eugenol concentration range of 60–210 mg/L, the recovered rate was 100%. The results indicated that eugenol is a safe and efficient anaesthetic for P. monodon.  相似文献   

3.
Nutrient apparent digestibility coefficients (ADCs) of pet food grade poultry by‐product meal (PBM) were determined for black tiger prawn, Penaeus monodon and Pacific white shrimp, Litopenaeus vannamei by the indirect method (reference diet and test diet at 7:3 ratio). Subsequently, an 8‐week growth trial was conducted to evaluate the effects of substitution of fishmeal (FM) with PBM in diets of P. monodon (initial weight = 0.21 ± 0.01 g). In the growth trial, six isonitrogenous and isoenergetic diets PBM0, PBM25, PBM50, PBM75, PBM100 and PBMA100, containing a gradient of PBM 0, 88.7, 177.4, 266, 354.7 and 354 g kg?1 to replace 0, 92.5, 185, 277.5, 370 and 370 g kg?1 FM were fed to four replicate groups respectively. The diet PBMA100 was supplemented with DL‐Met to be similar to PBM0. The results showed that both P. monodon and L. vannamei had relatively high ADC of crude protein (77.6% and 84.2% respectively) and gross energy (72.8% and 84.0% respectively) for PBM. Litopenaeus vannamei showed significantly higher digestion ability for PBM than P. monodon (P < 0.05). In growth trial, no significant difference in growth performance was observed among shrimp fed the experimental diets. DL‐Met supplementation did not improve the growth of P. monodon. PBM is a suitable protein ingredient for P. monodon feeds and can be used up to 354.7 g kg?1 to totally replaced FM.  相似文献   

4.
Heritabilities and genetic and phenotypic correlations were estimated for body weight (BW), body length (BL), carapace length (CL), carapace width (CW) and carapace height (CH) of the Penaeus monodon from measurements on progeny at 6 months of age resulting from a nested mating design. Estimation was made on data from 41 full‐sib and 10 half‐sib families. The estimated heritabilities for these traits were 0.13–0.24, and the significantly phenotypic and genetic correlations were 0.81–0.94 and 0.88–1.00, respectively. The present results indicate that genetic improvement through selective breeding conducted on P. monodon might be feasible and would be an efficient method to obtain a positive response to selection.  相似文献   

5.
Retinoblastoma (Rb) is a multifunctional regulator involved in several key cellular processes, such as cell cycle control, cell differentiation, tumorigenesis and senescence. In this study, an Rb‐like gene, PmRBL, was cloned from black tiger shrimp (Penaeus monodon). The full‐length cDNA sequence of PmRBL is 4,069 bp with an open reading frame of 3,243 bp, which encodes 1,080 amino acids. Quantitative real‐time PCR (qRT‐PCR) analysis indicated that PmRBL was highly expressed in the gills, hepatopancreas and ovaries of P. monodon. The highest PmRBL expression levels were observed in stage III of the ovarian development in P. monodon. RNA interference experiments were conducted to examine the expression profiles of PmRBL, PmCDK2 and PmCyclin E. The knockdown of PmRBL in the ovary and hepatopancreas by dsRNA‐RBL was successful. After dsRNA‐RBL was injected into the shrimp, the relative expression levels of PmCDK2 and PmCyclin E were upregulated at 12–72 hr in the ovaries and hepatopancreas. The localization and level of PmRBL expression in the ovary and hepatopancreas were investigated through in situ hybridization, which revealed consistent results with those of qRT‐PCR. Therefore, PmRBL, PmCDK2 and PmCyclin E may be involved in vitellogenin synthesis and ovarian maturation in P. monodon.  相似文献   

6.
This study investigated short‐term effects of increasing water temperature from 27 to 41°C on survival and feed consumption of Penaeus indicus at three different ages: PL25 (postlarvae 25 days old), PL50 and PL90. For each age group, water temperature was maintained at 27°C in the control, but increased to 32, 35, 38 and 41°C at a rate of 1°C every eight hours. The temperature was then kept stable until the end of the 7‐day experiment. Results showed that increasing water temperature affected both survival and feed consumption of the experimental shrimps (p < .01). Survival was highest at 32 and 35°C ranging from 93.8% to 100%, but significantly reduced to 40.0%–81.6% at 38°C. No shrimp survived the 41°C treatment. PL25 were more tolerant to 38–41°C than PL50 and PL90 in terms of survival. Increasing water temperature had no effects on feed consumption of PL25 (p > .05). For PL50 and PL90, feed consumption significantly increased at 38 and 41°C (p < .01) and was similar within the range of 27–35°C. This study suggests that P. indicus in tropical areas can tolerate water temperatures of at least 35°C and should be considered for farming during the summer time.  相似文献   

7.
A 60‐day indoor growth trial was conducted to study the effects of biofloc on the growth performance of a Penaeus monodon (Fabricius, 1798), water quality and biological indicators including biofloc volume, chlorophyll‐a, heterotrophic bacteria and Bacillus quantity. Two concentrations of sucrose (0 and 75%) were added daily to the P. monodon culture systems (2.94 ± 0.11 g), which were conducted indoors in fibre‐glass tanks (500 L). Results showed that the final body weight and weight gain of the adding 75% sucrose group were significantly higher (P < 0.05) than that of the control, as well as significantly (P < 0.05) improved specific growth rates and survival rates, and reduced feed coefficient. Adding 75% sucrose promoted heterotrophic bacteria, Bacillus and phytoplankton reproduction, and significantly (P < 0.05) reduced the concentration of ammonia‐N (NH4‐N), nitrite‐N (NO2‐N) and nitrate‐N (NO3‐N). The changes of water quality indicators in the two groups showed the similar trend at the end of the experiment, and the ammonia‐N, nitrite‐N, nitrate‐N and phosphate‐P concentrations in the 75% sucrose group were significantly (P < 0.05) lower than those of the control group, Chlorophyll‐a concentrations peaked at 389.12 μg/L in the biofloc sucrose group at 18:00 h, and heterotrophic bacteria peaked 8 h after sucrose was added. The addition of sucrose also reduced the pH of the water. Our research showed that adding sucrose promoted biofloc formation and shortened the formation time; increased the number of heterotrophic bacteria and algae which might play a role in improving water quality by assimilating ammonia‐N and other harmful substances in the water; supplemented food for P monodon growth; and reduced the feed coefficient.  相似文献   

8.
This study attempted to assess the efficacy of mangrove‐derived marine yeasts as a source of immuno‐stimulant in the tiger shrimp, Penaeus monodon. The shrimp was fed on the diets in supplementation with yeast biomass at 10% for a period of 15 days and then challenged with the pathogenic Vibrio cholerae. The animals were assessed for immune responses in terms of total haemocyte counts, phenol oxidase and endobiotics. Among the yeasts tested, Rhodotorula minuta was found to have high immunostimulatory effect in the shrimps especially after challenge with the pathogenic vibrio.  相似文献   

9.
Feeding experiment was conducted to determine whether fermentation and taurine supplementation of soybean meal (SBM) fed to yellowtail improve growth performance and lipid digestion. Six diets were formulated and designated as SBM, SBM supplemented with taurine (SBM + T), SBM fermented by Bacillus spp. (FSBM1), SBM fermented by Lactobacillus spp. (FSBM2), FSBM2 supplemented with taurine (FSBM2 + T), and fish meal (FM). Yellowtail fingerlings with an initial body weight of 42 g were stocked in 200‐L tanks. The fish were fed, each diet was fed twice daily in two separate tanks for 8 weeks. Results showed that lipid digestibility of the SBM diet was significantly lower than that of the FM diet, but SBM diet lipid digestibility was improved by taurine supplementation and fermentation. Lipase activity in anterior intestinal digesta, lipid contents in liver and muscle, and bile acid concentrations in gallbladder and anterior intestinal digesta were significantly lower in fish fed SBM diet than in fish fed FM diet; these parameters were not significantly different between fish fed SBM + T, FSBM2, FSBM2 + T diets and FM diet. Although taurine supplementation or fermentation improved lipid digestibility compared with FM diet, growth parameters were only improved in the fish fed FSBM2 + T diet, indicating that apart from a lack of taurine, SBM contains other factors responsible for inferior growth of yellowtail. These factors can be partially eliminated by Lactobacillus spp. fermentation.  相似文献   

10.
The objective of the present work was to evaluate the effects of different levels of vitamin E in feed on the spermatophore regeneration and quality of male Penaeus monodon. The experiment was carried out with the four following treatments: the basal diet no added vitamin E, the diet added 200, 600 and 1,000 mg/kg respectively. Spermatophore regeneration and quality were evaluated by spermatophore weight, sperm count and spermatophore absence rates, which male P. monodon were extruded spermatophore for feeding 20 and 40 days. In the experiment, the weight of the twice regenerated spermatophore of the males added to the vitamin E group was higher than that of the untreated control group. The weight of the first regenerated spermatophore with the addition of 1,000 mg/kg group was the highest and significantly higher than the control group (p < .05), but there was no significant difference among the three groups with different levels of vitamin E. The weight of the second regenerated spermatophore with the addition of 600 mg/kg group was the highest, followed by 1,000 mg/kg group, both of which were higher than the control group and the addition of 200 mg/kg group. Within the same group, the regeneration spermatophore weight showed overall upward trend as the feeding time, twice regenerate experiment spermatophore weight with added to the vitamin E groups were significantly higher than the initial value (p < .05), but three spermatophore weight of male shrimp at the control group had no significant difference. The sperm quantity and the percentage of normal sperm of the twice regenerated spermatophore of the males with added to the vitamin E group was higher than that of the untreated control group, and those of the addition of 200 mg/kg group was significantly higher than that of control group (p < .05). The total number of sperm and the percentage of living sperm of male shrimp in the experimental group decreased with the increase of vitamin E in the feed. Within the same group, the total number of sperm and the percentage of living sperm of male shrimp with added to the vitamin E groups showed overall upward trend as the feeding time and were significantly higher than the initial value (p < .05), but the control group was slightly down and had no significant difference. Comprehensive sperm weight, sperm quantity and living sperm percentage of three indicators, that adding 200 mg/kg of vitamin E in feed could effectively promote the spermatophore regeneration in the male P. monodon and improve the sperm quantity. The experimental results provide a scientific basis for the breeding of P. monodon.  相似文献   

11.
Two trials were conducted to compare L‐lysine HCl and L‐lysine sulphate regarding its availability to Penaeus monodon, and further evaluate the optimum dietary lysine requirement. In experiment 1, five experimental diets were formulated (D1, D2, D3, D4 and D5), a basal diet (D1), aimed at a low‐lysine concentration (2.22% dry matter), with lysine concentration of the other four diets increasing in two 0.25% L‐lysine intervals from either L‐lysine HCl (D2 and D3) or L‐lysine sulphate (D4 and D5). Each diet was fed at a restricted rate to three groups of 40 shrimp for 74 days. The highest values of growth performance (weight gain, WG; specific growth rate, SGR) and survival were observed with shrimp fed the L‐lysine HCl diet. Feed efficiency (FE) of shrimp fed D2 was significantly higher than that of shrimp fed D1 and D5 (P < 0.05), but without significant difference with shrimp fed D3 and D4 (P > 0.05). In experiment 2, six diets (d1, d2, d3, d4, d5 and d6) were formulated with six graded levels of lysine (2.21%, 2.41%, 2.59%, 2.87%, 3.11% and 3.29% of diet). Each diet was randomly assigned to triplicate groups of 40 shrimp for 74 days. WG, SGR and survival increased increasing levels of lysine up to 2.41% of diet and reached an apparent plateau. Broken‐line model analysis on WG and SGR indicated that the optimum dietary lysine level for optimal growth of shrimp was 2.37% of diet, corresponding to 5.78% of dietary protein. In conclusion, results of this trial suggest that L‐lysine HCl is superior to L‐lysine sulphate when fed to Penaeus monodon and optimal growth can be obtained at lysine levels corresponding to 2.37% of diet, or 5.78% of dietary protein in this specie.  相似文献   

12.
An indoor feeding trial in a flow-through marine water system was performed to evaluate the feasibility of using dehulled lupin Lupinus albus seed meal as a protein source to replace fish meal in diets for the juvenile Penaeus monodon. Five isonitrogenous (40% crude protein) diets formulated by replacing 0, 25, 50, 75, and 100% of fish meal protein by lupin meal protein were fed to shrimp (mean initial weight of 4.32 ± 0.23 g) three times daily at a feeding allowance of 5% body weight per day for 42 days. Shrimp fed diets with 0, 25, 50 and 75% replacement had similar (P > 0.05) weight gain, dry matter feed intake, feed conversion ratio (FCR), protein efficiency ratio (PER), and apparent net protein utilization (ANPU). Shrimp fed the highest dietary inclusion level of lupin meal (100% replacement) had significantly (P < 0.05) lower responses for all the above parameters than shrimp fed all other diets. Survival was high (87–100%) and similar for all diets. Apparent dry matter digestibility (ADMD) of diets with 25, 50, 75 and 100% replacement of fish meal with lupin meal was similar (75.6–76.6%) and significantly (P < 0.05) higher than that of diet with 0% replacement (73.9%). Diets containing the two highest lupin inclusion levels (75 and 100% replacement) had significantly (P < 0.05) better apparent protein digestibility (APD) than those containing the two lowest lupin meal inclusion levels (0 and 25% replacement). There were no significant differences (P > 0.05) in whole-body composition (dry matter, protein, lipid and ash) of shrimp fed on the various diets. Pellet water stability was inversely related to level of lupin meal inclusion. It was found, in this study, that up to 75% protein of fish meal can be replaced with the protein of dehulled lupin seed meal in diets for juvenile P. monodon. The diet with total replacement of fish meal containing 40% lupin meal was utilized very poorly by the shrimp.  相似文献   

13.
At present the most common and most devastating disease of shrimp is caused by the white spot syndrome virus (WSSV), which has spread throughout the world mainly by different species of crustaceans carrying the virus. After experimental injection of Penaeus monodon with a known copy number of WSSV in the abdominal muscle, the rate of viral progression in different tissues at 12, 24, 36 and 48 hpi (hours post infection) was assessed using quantitative real‐time PCR. At 12 hpi the viral load was highest in haemocytes followed by pleopod, muscle and gills whereas at 48 hpi, the gills, the main target of WSSV, showed the highest viral load followed by pleopod, muscle and haemocytes. Viral copy number in the haemocytes was the lowest beyond 12 hpi indicating a remarkable reduction in the rate of viral replication in haemocytes compared with other tissues. The viral load in haemocytes, though increased again beyond 36 hpi, never surpassed the load in the other tissues. The real‐time PCR assay with its high sensitivity and wide dynamic range make it ideal for detecting low‐level WSSV infections that can occur in apparently healthy P. monodon.  相似文献   

14.
An experiment was conducted to assess the effect of supplementation of cellulolytic gut bacterium with plant protein‐based diet on growth, digestibility and digestive enzyme status of tiger shrimp, Penaeus monodon. Bacillus sp. DDKRC1. (JN641289), a potential cellulolytic bacterium, isolated from the gut of Asian seabass was used as feed supplement in this experiment. The shrimps of group I, II and III were fed with control diet (without bacterial supplement, D1), diet supplemented with live Bacillus sp. DDKRC1. at 2.94 × 107 cfu per 100 g feed (D2) and diet fermented (48 hr) with same bacteria (D3) respectively. At the end of the 42 days experiment, shrimps of group II showed significantly better (p < .01) growth and protein efficiency ratio (PER) and lower (p < .01) feed conversion ratio (FCR) as compared to group I and III. Dry matter, cellulose, hemicellulose and lipid digestibilities were significantly (p < .01) higher in group II than other two groups. Cellulase, amylase and protease activities in the gastrointestinal (GI) tract were significantly (p < .01) higher in group II as compared to other two groups. Total heterotrophic count, amylolytic, cellulolytic and proteolytic bacterial counts in gut were significantly (p < .01) higher in group II as compared to other two groups. Haematological analysis indicated better (p < .05) immune response in groups II and III than control group. Diets D2 and D3 showed better effect on growth, digestibility, FCR, survival and immune response of P. monodon as compared to D1.  相似文献   

15.
The effect of six different binding agents (agar, sodium alginate, cassava starch, gelatin, wheat gluten and kelp meal) in two concentrations (30 g kg−1 and 50 g kg−1) were evaluated with respect to physical quality of Litopenaeus vannamei broodstock pelleted feed, after 15, 30, 60, 90, 120, 150 and 180 min of water immersion. The best treatments in terms of water stability, water absorption and protein leaching were obtained with sodium alginate and wheat gluten at 50 g kg−1. In a second experiment, the feed ingestion and diet digestibility with these two binders and their combination (1 : 1) were compared against a control diet containing 50 g kg−1 wheat flour. There were no significant differences (P > 0.05) in the daily feed ingestion rate 2.39–3.33% of the biomass. The most representative values of apparent digestibility of protein (ADP) and apparent dry matter digestibility (ADMD) were achieved with diets containing wheat gluten and alginate + gluten mixture as binder. Based on these results, combinations with 50 g kg−1 wheat gluten is recommended as binder in pelleted feed for broodstock L. vannamei.  相似文献   

16.
Different levels of dietary chitosan on growth performance, survival and stress tolerance to air exposure was studied in tiger shrimp, Penaeus monodon. Shrimp (mean initial wet weight about 1.16 g) were fed with six different diets (C0, C0.05, C0.1, C0.2, C0.3 and C0.4) containing six level of chitosan (0%, 0.05%, 0.1%, 0.2%, 0.3% and 0.4% respectively) in triplicate for 60 days. Growth performance [final body wet weight (FBW); weight gain (WG); biomass gain (BG)] of shrimp fed chitosan‐containing diets were higher (P < 0.05) than that of shrimp fed the basal diet, shrimp fed C0.1 diet showed the highest value of growth performance. Survival of shrimp in C0.1 and C0.2 diet groups were higher (P < 0.05) than that of shrimp in C0, C0.05 and C0.4 diet groups but without statistical difference (P > 0.05) in shrimp fed C0.3 diet group. Whole body and muscle lipid contents decreased with increasing dietary chitosan levels. Plasma total cholesterol and triglyceride contents of shrimp fed C0 diet was significantly higher (P < 0.05) than that of shrimp fed chitosan‐containing diets. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities of shrimp fed C0 diet were higher than those of shrimp fed chitosan‐containing diets. Digestive gland malondialdehyde (MDA) and carbonyl protein contents of shrimp fed chitosan‐containing diets were lower (P < 0.05) than that of shrimp fed C0 diet. Total haemocyte count of shrimp fed C0 diet was lower (P < 0.05) than that of shrimp fed chitosan‐containing diets. On the contrary, the haemolymph clotting time of shrimp fed C0 diet was higher (P < 0.05) than that of shrimp fed chitosan‐containing diets. In conclusion, all results suggested that dietary intake containing 0.1% and 0.2% chitosan enhanced the growth of shrimp, whereas a higher level than 0.3% and 0.4% decreased growth of shrimp. Second‐degree polynomial regression analysis of WG and BG indicated that the optimum supplement of dietary chitosan level should be 0.19–0.21%.  相似文献   

17.
White spot disease (WSD) caused by white spot syndrome virus (WSSV) creates severe epizootics in shrimp aquaculture industry worldwide. Despite several efforts, no such permanent remedy was yet developed. Selective breeding using DNA markers would be a cost‐effective strategy for long‐term solution of this problem. In the present investigation, out of 30 random primers, only one primer produced a statistically significant (P < 0.01) randomly amplified polymorphic DNA (RAPD) marker of 502 bp, which provided a good discrimination between disease resistant and disease susceptible populations of Penaeus monodon from three geographical locations along the East coast of India. Because RAPD markers are dominant, a sequence characterized amplified region (SCAR) marker was developed by cloning and sequencing of 502 bp RAPD fragment, which generates a single 457 bp DNA fragment after PCR amplification only in the disease resistant shrimps. Challenge experiment was also conducted to validate this 457 bp SCAR marker, and the results suggested that the WSSV loads were 2.25 × 103 fold higher in disease susceptible than that in disease resistant shrimps using real‐time PCR. Therefore, this 457 bp DNA SCAR marker will be very valuable towards the development of disease‐free shrimp aquaculture industry.  相似文献   

18.
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19.
A survey on the presence of the viruses of two economically significant diseases, white spot syndrome virus (WSSV) and monodon baculovirus (MBV) in wild‐collected Penaeus monodon broodstock, was conducted during different seasons of the year in two major coastal areas of southeast India. The broodstock were collected along the coast of Tamil Nadu and Andhra Pradesh during summer, premonsoon, monsoon and post‐monsoon seasons for three consecutive years. A total of 7905 samples were collected and subjected to MBV screening, and 6709 samples that were screened as MBV negative were diagnosed for WSSV. MBV was detected using rapid malachite green staining and WSSV by nested polymerase chain reaction. Prevalence data of the viruses were analysed using the EpiCalc 2000 program at 95% confidence interval. Samples collected from the Andhra Pradesh coast displayed a slightly higher prevalence of WSSV and MBV infection than those collected from Tamil Nadu, although this difference was not statistically significant (P > 005). In addition, it was found that the prevalence of both WSSV and MBV infections fluctuated according to season. Data on prevalence of these viruses in broodstock would be useful to develop strategies for shrimp health management along the southeast coast of India.  相似文献   

20.
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