7 research outputs found

    Assessment of different methods of water treatment on decreasing pathogenic bacteria in shrimp hatcheries

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    The project of "Assessment of different methods of water treatment on decreasing pathogenic bacteria in shrimp hatcheries" achieved by mean of reviewing the effectiveness of various methods on the water treatment to reduce bacterial load of sea water. The project performed in Bandargah region of Bushehr province in order to checking the effect of different methods on the sea water and bacterial population. This project has been done over a year. In this study a total of 138 samples was collected during seven times and was evaluated as well as 7 treatments. In this study, the comparison of the effect of each factors (sand filter, chlorine, ultra violet ray, chlorine combined with ultra violet ray) was analyzed on the sea water by means of disinfection. During this study, other environmental factors such as water temperature, dissolved oxygen, pH and salinity was measured till we can ensure that they don’t have any negative impact on the treatments. Results showed that the density of total bacteria in sea water (Control) was averagely 5187 CFU/ml, this was done while the total density of bacteria in the sea water, reservation pool sample, sand filter water, water that irradiated with ultraviolet rays, chlorinated water and the water that was influenced by both chlorine and ultra violet ray was respectively 5187 2137, 4449 2042, 2782 1335, 1164 692, 143 104, 87 76 CFU/ml. Therefore, reservation pool, sand filter, ultra violet ray, chlorine, chlorine-ultra violet ray each of them was reduce respectively 14, 46, 77, 97, 98 percent of the density of total bacteria or in other words they reduced 0.06, 0.27, 0.65, 1.56, 1.77 log of the total population of bacteria in water. Moreover, the results from the total count of vibrios showed that reservation pool, sand filter, ultra violet ray, chlorine, chlorine-ultra violet ray each of them was reduce respectively 17, 47, 74, 98, 99 percent of the density of total vibrios or in other words they reduced respectively 0.08, 0.27, 0.59, 1.66, and 1.95 log of the total population of vibrios in sea water. Also the bacteria that isolated from each treatment were identified with the use of biochemical methods that totally were includes a wide range of bacteria, the identified vibrios were: Vibrio alginolyticus, V. costicola, V. fischeri, V. fluvialis I, V. fluvialis II, V. harveyi, V. natriegens, V. nigripulchritudo, V. parahaemolyticus, V. plagius I, V. vulnificus, V. anguilarum I, V. campbellii, V. nereis, V. proteolyticus, V. splendidus, and Unknown V. spp. Other identified bacteria belonging to the following genus: Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Borkholderia, Eschricia, Enteroacter, Flavobacterium, Micococcus, Proteus, Pseudomonas, Serratia, Staphaphylococcus, Streptococcus, and Unknown Bacteria spp. By comparing the results, we concluded that the best result was related to treatment that the sea water had been disinfected after the combined effects of chlorine and ultraviolet ray. It was determined that this process in compared with other treatments, had been reduced the total number of bacteria, the total number of Vibrios, the number of sucrose fermentative vibrios, and the number of non-sucrose fermentative vibrios respectively 98, 99, 98, 99 percent. In other words, the number of bacteria was reduced respectively 1.77, 1.94, 1.82, 2.23 log. So in this study, the applied method was introduced as the most effective way of disinfecting sea water. Meanwhile, none of pathogenic bacteria for shrimp including Vibrio harveyi was isolated by using this treatment. Comparing the results showed that the combined effects of chlorine and ultraviolet radiation is the most effective applied method for disinfecting sea water

    Manufacture of artificial diet to feeding of western white shrimp (Litopenaeus vannamei) in larval stages and in comparison with import diet

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    For the accomplish of project, nine treatments with three replicate in each treatment, used as follows. Control treatment: Feeding with natural foods (Chaetoceros sp and artemia nauplii) Treatment 1: Feeding with combination of inner artificial diet and natural foods. Treatment 2: Feeding with combination of imported artificial diet and natural foods. Treatment 3: feeding from zoea 1 to mysis 1 with chaetoceros sp and from mysis 1 to pl15 with inner artificial diet. Treatment 4: feeding from zoea 1 to mysis 1 with chaetoceros sp and from mysis 1 to pl15 with imported artificial diet. Treatment 5: feeding from zoea 1 to pl15 with project artificial diet. Treatment 6: feeding from zoea 1 to pl15 with imported artificial diet. Treatment 7: Feeding in zoeal stages with chaetoceros sp and from mysis 1 to pl15 with chaetoceros sp+artemia nauplii+ imported artificial diet. Treatment 8: Feeding in zoeal stages with chaetoceros sp and from mysis 1 to pl15 with chaetoceros sp+artemia nauplii+ project artificial diet. Larvae stocked at a density of 100 nauplii/ L-1 (1000 nauplii in each tank each tank), at the beginning of culture period The results showed that, in treatments 1, 2, 7 and 8 from zoea 1 to pl15, growth indexes were suitable and noticible, and in most treatment better than control treatment. Survival percent, in pl15 in treatment 1, 2, 7 and 8 was more than control treatment, and differention between treatment 1, 2 and 8 in comparision with control treatment was statictically significant (p0.05). But thereafter, significantly decresed. In treatments 3 and 4 from zoea 1 to late mysis 3 stage, survival percent in comparision with other treatments were suitable, and thereafter, significantly decreased, and with statictically significant with other treatments (p0.05), but in treatment 8, was more than other treatments. The mean of final length between treatments 1, 2, 6, 7, 8 and in comparision with control treatment, were not statistically significant (p>0.05). But in treatment 2, more than control treatment, and in other treatments less than control treatment

    Investigation on possibility of survival and growth enhancing by selected seaweeds from Persian Gulf in post larvae shrimp Litopenaeus vannamei

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    The use of antibiotics in aquaculture has been limited. Scientifics seeking for natural substitutes to prevent of aquatic animals diseases. Considering seaweeds are rich of nutritions and bioactive compounds, the propose of this study is: investigation the potential and use possibility of native seaweeds from Persian Gulf in shrimp aquculture industry to improve growth, survival of postlarvae and to resistance against pathogens such as vibriosis. For this propose 7 macroalgaes species from Bushehr province coast, inclouding: green algae (C.iyengarii), brown algae (S.angutifolium and S.ilicifolium) and red algae (L.snyderiae, K.alvarezii and G.corticata) were collected and identified. Then seaweed extracts abtained by Water, Ethanol, Methanol and Chloroform solvents by soaking method. In vitro antibacterial activity of extracts against Gr^+ bacteria (S.aureus and B.subtilis) and Gr- bacteria (V.harveyi,V.alginolyticus and E.coli) was conducted by Agar diffusion, MIC and MBC methods. Antioxidant activity also by DPPH and EC_50 methods was investigated. According to results of these two tests four seaweeds species (S.angutifolium, L.snyderiae, K.alvarezii and G.corticata) were selected for use in shrimp postlarvae (PL22) diets by Bio-Encapsulation (Artemia enrichment). Before of enrichment, toxicity effect of extracts to Artemia naplii were evaluated by determination of LC_50 24 h method. From results of this section Ethanol extracts were selected to bioencapsulation. After encapsulation shrimp postlarvae divided to 12 groups in triplicate, namely: C^-, C^+, S (200), S (400), S (600), L(200), L(400), L(600), G(300), G(600), K(300) and K(600). During 30 days of reared period C- and C+ use of basal diet and unenriched Artemia, but the other groups use of basal diet and enriched Artemia. Except C-, the shrimps in first day of culture put in 107 cfu/ml v.harveyi suspension for 30 minutes, and after water exchange 10 ml of this dose was added to reared aquaria. After 30 days survival percentage, obtained weight and SGR% were investigated. To evaluate vibrio loadind, every 10 days 5 postlarvae were sampled randomly for vibrio count. Results showed that vibrio count in C^- was less than the others and in C^+ was more than the others. In treatments vibrio count in L(200) was the most and L(600) was the less. Survival rate in C^- was the most and after that G(600) with 79.4±6.6% and then S(300) and K(600) were 73.3±7.3% and 70.6±6.6% respectively that were significantly compare the other (P < 0.01). Also the C+ was the less with 33.3±6.6% that difference was significant (P< 0.01). In this study growth parameters of all groups that fed by enriched Artemia were better than C^+ (P<0.05). After cultre period 10 shrimp of every aquarium disinfected and reared for 10 days like before treatment. After 10 days the shrimps were challenged by 3×108 cfu/ml V.harveyi and mortality was recorded for 7 days. The all of animals in C^- were survive but more than 90% of C^+ were dead. And survival in all of treatments were better the C^+ (P<0.05). the study showed the ethanol extracts of selsected seaweed from Persian Gulf is a good source for growth, Survival and disease control in shrimp larviculture

    Supply and protected different population of Litopenaeus vannamei subadult zero foster (F_0) from difference provinces Iran

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    Nowadays, Litopenaeus vannamei are the most important species of farmed penaeidae shrimp in the world that is rapidly replacing native species in areas aquaculture. Due to demand increase for this species culture, shrimp displacement to different areas may be associated with some potential pathogens transferred to new areas farmed. Therefore, in this study were prepared bi-osecurity conditions for specific disease-free production of L. vannamei. Thereafter, three populations (Molokaei, High health and mix of Molokaei and High health) of the shrimp various reserves were detected base on origin and genetic indexes such as: observed heterozygosity, expected heterozygosity, allele frequency, coefficient inbreeding, genetic differentiation, genetic distance and genetic identity. On the other hand, epidemiological studies indicate non pathogens (viral, bacterial, fungal and parasitic) recognition of different populations selected in the quarantine salon. The bioassay results showed that the average weight and length of the populations of High health and Mix significantly greater than was a population of Molokaei. The shrimp populations were stocked in fiberglass tank (five ton) and were kept separated in the quarantine salon. During maintenance shrimp of populations in the quarantine salon were evaluated living and non-living pathogens with PCR, microbiology and biochemical methods. There is not any pathogens detection from shrimp populations stocking in the quarantine salon, so the shrimps were carried over to pond for broodstock culture of specific pathogenic free

    Evalution of genetic different between Litopenaeus vannamei of different race

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    In this study, after determining history of origin entering white leg shrimp of broodstocks at hatcheries of country, finally, two population of Molokaei and High health were considered as shrimp broodstocks of specific disease free (SPF) zero generation. After inbreeding and cross breeding among adult males and females of two population above, three storage different were produced in the first generation: H♂ × M♀, M♂ × H♀ and H♀ × H♂. The second generation were produced from selective breeding of M♂ × H♀. The aim of this study was to determine genetic differences between different generations of specific pathogenic free shrimp by evaluation of 16S rRNA region mitochondrial of different generations. Result of this study showed that of 486 sites have been identified 484 sites were conserved. Also, monomorphic sites ranged between 482 - 486 sites and was consists 2 polymorphic sites and 2 transitional sites. The number haplotypes, haplotypes diversity, nucleotide diversity revealed in this region were 2, 0.356±0.159 and 0.00147, respectively. Due to the high genetic identify and reduce of genetic distance of shrimp between different generations of SPF shrimp, genetic differentiation and gene flow (Nm) between them were -.142 and -2.00, respectively. This rates clearly shows a low level of polymorphism in this region of mitochondrial of different generation of SPF. This may be occurred because of small effective populations and genetic drift. Thus, offspring had inherited mitochondrial genome from your mother, therefore, it is expected that rate of variation in this genome is influenced by several factors, including genetic drift, due to unavailability of new-broodstock from different areas. It was observed that due to high conservation sites in 16S rRNA region of mitochondrial genome, nothing genetic differentiation was observed among different generations of SPF

    Stock enhancement and estimation of growth rate of green tiger prawn (Penaeus semisulcatus) and banana shrimp (Fenneropenaeus merguiensis) released in the Persian Gulf

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    Present study was conducted in the Persian Gulf (Iranian waters) from 2009 to 2012. The main objective of the research was economical evalution of the stock enhancement of banana prawn (Fenneropenaeus merguiensis) and green tiger shrimp (Penaeus semisulcatus) in the studied area. Also tagging effects on the growth and mortality of tagged shrimp were studied. In banana prawn, broodstock shrimps were hatched in June. In July 2010 and 2011some of the juvenile of this species were marked by red fluorescent liquid injection and released were made at night in the estuaries of Tiab, Kolahi and Koolgan in the Hormozgan province. 84000 juveniles of banana prawn in 2010 and about 50000 in 2011 were released in this area. In Bushehr province waters, adults shrimp were reared and when juveniles reached to optimum size, some of them were tagged by red and blue coloures and were released in the coastal waters of Bandargah and Delvar. Tagging and releasing program of green tiger prawn was performed in 2010 and 2012. A total number of 8000 prawn in 2010 and about 30000 juveniles prawn in 2010 were released. Activities for recaptured shrimps were informed by posters describing the tagging program that were distributed to local peoples, as well as local magazines, and a tagging program awareness film was broadcast on national television three times prior to the shrimp fishing season and during catch season. To encourage people to report recaptures a reward of two handered thousent riales was paid for the return of each marked shrimp accompanied by information. Economical evaluation of banana prawn was performed based on releasing and recaptured program in 2011. As it mentioned in this year 50000 of juvenile shrimp were tagged and released. At the same time 4700000 of unmarked shrimp were released in this area. In the shrimp season 11 (./022%) of tagged shrimp were recaptured. Movements of tagged shrimp were northwesterly to released area. Weight average of tagged prawns was 1.2 gram. Mean weight of the recaptured prawns was 22.06±4.9 gram. Body weight Growth of the recaptured prawns was between 16-26 grams with the growth speed of 0.88-1.41 per week. The number of recaptured prawn to the released prawn was 0.022 percent. Based on the released prawns (4700000) to the recaptured percent (./022%), about 103400 of released shrimp with mean weight of 2.5 tones were observed in the Hormozgan shrimp catch. The average price of shrimp in the studied year in the local market was 85000 Rials per kilogram. These results showed that the ratio of profit is 210 milion riales. In the taggiing program of green tiger prawn in the Bushehr waters only one recaptured shrimp was observed in the catch season (2012). Total weigth and total length of this prawn was 99 gram and 22 centimeter respectively .given the small percentage of the recaptured, economical analyses was not performed on this species. The effects of tagging on the growth and mortality of green tiger prawn were studied. The present study was carried out in the shrimp research station in Bandargah and Abzistan shrimp Hatchery Company in Delvar during 2010 and 2012. The accuracy of the study was more rialable in 2012. In this year growth and mortality of juveniles that was marked by red and blue coloures, were studied in both area Bandargah and Delvar. In Bandargah, three tanks of 300 l each with 30 specimens were used for untagged shrimp as a control group, and tagged with injected liquid fluorescent during 98 days. Length and weigh of 10 specimens were measured evenly in different times. ANOVA results (α = 0.1 and α = 0.5) showed no significant differences between length growth of tagged shrimp and control group. The mortality of two groups was evaluated by numbering of remained shrimps and the average of survival was 52 percent in the tagged and 44.5 percent in tagged shrimps. In the Delvar station, Abzistan Company, the specimens were kept in the 9 tanks each 300 l that included of 30 untagged shrimps, 30 blue tagged shrimps and 30 red florescent tagged shrimp. The growth and mortality of this station were evaluated during 110 days. The growth rate of the specimens were measured and recorded evenly. The results of ANOVA (α = 0.1 and α = 0.5) showed no difference significantly in the weight growth of tagged and control groups. The mortality rates among the control group, red tagged and blue tagged were 63 percent, 59 percent and 40 percent. The mortality of the groups was differences in the two stations and it seems the management and environmental conditions were more affected on the mortalities. The results of the study show that the ratio of profit to the coast is 0.46 that is covering half of the coasts, so that the expenditures are two times more than profit. This result is the minimum of economical value of stock enhancement of shrimp. The results of study showed that the injected tags into the body tissue of shrimp has no affected on the growth rate and mortality

    Supply and protected different population of Litopenaeus vannamei subadult zero foster (F0) from difference provinces Iran

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    Nowadays, Litopenaeus vannamei are the most important species of farmed penaeidae shrimp in the world that is rapidly replacing native species in areas aquaculture. Due to demand increase for this species culture, shrimp displacement to different areas may be associated with some potential pathogens transferred to new areas farmed. Therefore, in this study were prepared bi-osecurity conditions for specific disease-free production of L. vannamei. Thereafter, three populations (Molokaei, High health and mix of Molokaei and High health) of the shrimp various reserves were detected base on origin and genetic indexes such as: observed heterozygosity, expected heterozygosity, allele frequency, coefficient inbreeding, genetic differentiation, genetic distance and genetic identity. On the other hand, epidemiological studies indicate non pathogens (viral, bacterial, fungal and parasitic) recognition of different populations selected in the quarantine salon. The bioassay results showed that the average weight and length of the populations of High health and Mix significantly greater than was a population of Molokaei. The shrimp populations were stocked in fiberglass tank (five ton) and were kept separated in the quarantine salon. During maintenance shrimp of populations in the quarantine salon were evaluated living and non-living pathogens with PCR, microbiology and biochemical methods. There is not any pathogens detection from shrimp populations stocking in the quarantine salon, so the shrimps were carried over to pond for broodstock culture of specific pathogenic free
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