In the present study selenium nanoparticles (Se-NPs) and zinc nanoparticles (Zn-NPs) included in the diets of white shrimp at 0 mg (control), 0. 3 mg Se-NPs/ kg feed (T1), 0. 15 mg Se-NPs+15 mg Zn-NPs/kg feed (T2) and 30 mg Zn-NPs/kg feed (T3). After 8 weeks, shrimps fed both Se-NPs and Zn-NPs showed higher (p<0. 05) final body weigh, weigh gain, and SGR than shrimp fed the control diet. On the other hand, the FCR was decreased by Se-NPs and Zn-NPs when compared to the control whereas both Se-NPs+Zn-NPs revealed lower FCR than the other groups (p<0. 05). Shrimp fed Se-NPs or Se-NPs +Zn-NPs revealed higher survival rate than shrimp fed the control and Zn-NPs while shrimp fed Zn-NPs showed higher survival rate than shrimp fed the control (p<0. 05). The total haemocyte count, large granular cells, semi granular cells, and semi granular cells revealed higher counts in shrimps fed Se-NPs and Zn-NPs than the control (p<0. 05). Shrimp fed Se-NPs or Se-NPs+ Zn-NPs revealed higher catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidas (GPX) activities than shrimp fed the control and Zn-NPs while shrimp fed Zn-NPs showed higher catalase activity than shrimp fed the control (P<0. 05). The total protein, lysozyme, and phenoloxidase activities increased in shrimp fed Se-NPs or/and Zn-NPs with the highest being in shrimp fed both in shrimp fed Se-NPs and Zn-NPs followed by those fed Se-NPs then Zn-NPs when compare to the control (p<0. 05). In conclusion, the co supplementation of Se-NPs and Zn-NPs showed higher performances, antioxidant status, and immune responses in white shrimp than the individual supplementation of Se-NPs or Zn-NPs.

Shrimp culture, one of the most profitable industries, needs to be modified by modern techniques in Iran. The present study was focused on the effects of applied biofloc technology (BFT) on Pacific white-leg shrimp (Litopenaeus vannamei) culture, as a new system (zero-water exchange) to improve the immunity of shrimp and the water-quality factors in challenge with Vibrio harveyi. Biofloc systems were established by increasing the carbon/nitrogen (C/N) ratio by adding sugar as a carbohydrate source to the culture media. The immune system indices, and growth factors of shrimp were then measured along with water quality parameters and loads of Vibrio harveyi compared to the traditional water-exchange system. The results showed that using BFT led to decreasing levels of the toxic nitrogenous substances such as TAN, NO3, and NO2, which in turn resulted in decreasing the water exchange frequency. It was also observed that the shrimp could feed on flocs resulted in improvement the growth factor and immune system. On the other hand, despite the increased loads of V. harveyi bacteria, there was no significant difference in shrimp survival between the biofloc and traditional systems. These observations were confirmed by evaluating immune system factors (total hemocyte count (THC), total plasma protein and phagocytosis activity of the hemocytes. Generally, this study showed that rearing pacific white-leg shrimp in BFT in can preserve water quality and enhance shrimp’s growth and immune responses, compared to the traditional systems.

Bacterial infections are major limiting factors in shrimp culture that lead to great economic losses to the farmers. This study aimed to investigate the effects of Solen vagina acetone extract (AE) on some immunity parameters and bacterial infection by Vibrio harveyi in Litopenaeus vannamei. 5000 L. vannamei postlarvae were exposed to five concentrations (100, 150, 200, 250, and 300 mg/L) of S. vagina in triplicates for 3 weeks. A positive control (exposed to the bacteria without any AE) and a negative control (without bacteria and AE) were also considered in this study. Each group contained 600 post larvae. The highest mortality was observed in the groups with concentrations of 100 and 150 mg/L AE and the lowest was observed at a concentration of 250 mg/L AE. None of the concentrations had a significant effect on the physical and chemical properties of water. According to the histopathology analyses, the exposed post larvae showed deformation symptoms in hepatopancreas cells. Based on the results, AE could reduce and prevent mortality caused by Vibrio harveyi. Also, the minimum inhibitory concentration of AE for V. harveyi was 200 mg/L.

This study aimed to examine the effect of fatty acid in the diet on changes the incidence of the Red-head Syndrome under temperature stress and hypoxia in white leg shrimp (Litopenaeus vannamei) during 8 weeks. For this purpose, shrimps were fed by 4 diets (diet 1: containing 7. 02% of total fat,diet 2: containing 6. 41% of total fat,diet 3: containing 8. 05% of total fat,diet 4: containing 6. 41% of total fat with 1750 mg/kg of vitamin E), under 3 stressors (S1: no challenge to environmental stresses,S2: with hypoxic stress (2. 0±1. 0 ppm),S3: with increasing temperature stress (36±2°C). The results of the hypoxic stress on the incidence of redness in L. vannamei fed with different levels of fatty acids showed that there were differences significantly (p<0. 05). Temperature increase although showed no differences between healthy shrimps(p>0. 05) but, there were significant difference among red-headed shrimp in treatment 1, 2 and 3 (p<0. 05). The examination in treatments 2 and 3 showed hepatopancreatic were loss the columnar structure so thatelongated cells and dilated tubules were observed. Some B cells had no vacuoles and were not fully developed. The number of R cells was low and basophilic F cells were convex. In treatment 4, the cells have few reserves and were normal. Some B cells were degenerated. The height of the tubules was lower than normal, but no inflammatory reaction was observed in the tissue. In treatment 4, cell showed better conditions than treatments 2 and 3. Accordingly, B cells were present well and R cells showed moderate storage. In general, it can be concluded that the use of vitamin E can reduce the complication of redness and minimal cell damage to hepatopancreatic tissue in L. vannamei.

The effect of different concentrations of Ocimum basilicum extract supplement on growth and survival of Western white leg shrimp (Litopenaeus vannamei), juveniles was investigated. Shrimps were separated into four experimental groups of 0 (Controls), 60, 120 and 240 ppm extracts of O. basilicum. The photoperiod was regulated to a 12: 12 dark/light cycle and molts, feces and dead shrimps were daily removed and 30% of water in each tank was exchanged by new sea water. Biometry was done once a week. Extract supplemented diet did not have any significant effect on weight gain (%), final weight (g), growth performance, feed utilization and body composition of L. vannamei when compared to shrimp in the control diet. It was also observed that the shrimp fed the diet containing 120 ppm O. basilicum extract obtained the highest weight gain (%) 6. 23 ± 0. 12% and the lowest rate (5. 7 ± 0. 1%) was for 240 ppm extract. In conclusion, dietary O. basilicum extract supplementation had no significant effects on the growth performance, survival rate, feed utilization and carcass composition of Western white leg shrimp juveniles. The positive results obtained encourage conducting further research on the administration of O. basilicum extract on Western white leg shrimp or other economically important species but with longer duration of culture period.

This study aimed to investigate the effect of sea cucumber methanol extract on Vibrio harveyi and also to investigate the measurement of changes of factors in farmed shrimp, Penaeus vannamei. Holothuria parva with an average length of 15-10 cm were collected from tidal coasts of Dayyer city, Bushehr province. Different concentrations of H. parva extract (50, 100, and 150 µg/mL) were used to prepare the food of the experiment. Vibrio harveyi bacterial strain (PTCC: 1755) was obtained from the Collection Center of Industrial Microorganisms of Iran. Thousand shrimp with an average weight of 10±1 g were collected from culture ponds and distributed among 15 aquariums containing 100 liters of water with a salinity of 40 ppt. The mean comparison of survival rates showed that there was no significant difference among treatments on the first day (p>0. 05). Also, there was significant difference among survival rates in other treatments with negative and positive control treatments (p<0. 05). The results also showed that there was significant difference among the groups in PO (phenol oxidase), POD (peroxidase), THC (total haemocyte count), TPP (total plasma protein), and SOD (superoxide dismutase) with the amounts of negative and positive control treatments during the experimental days (p<0. 05). The highest amounts of measured factors were 538. 18±14. 45 U min-1 mL-1 (Treatment 3) for PO on the fifth day, 7. 19±0. 3 nmol min-1 mL-1 (Treatment 2) for POD on the fifth day, 37. 98±6. 49×105 cell mL-1 (Treatment 3) for THC on the third day, 93. 67±14. 8 mg mL-1 (Treatment 3) for TPP on the third day, and 1663. 21±37. 07 activity U mL-1 (Treatment 3) for SOD on the third day. According to the results, survival was directly related to the concentration of methanolic extract. The highest increase in safety factors was observed in treatment 3, with concentration of 150 µg / mL methanolic extract of sea cucumber.

In this study, the effects of white-leg shrimp hydrolysate protein extracted in a progressive rise in temperature (40-60°C) (Gradual) and without centrifugation (Mix) on the colon cancer cells were determined. Both bioactive peptides were prepared using enzymatic hydrolysis with alcalase. The cytotoxic effect on HCT-116 cell line was evaluated using the Neutral red and MTT assay. In-vitro, antioxidant activity was performed using DPPH, TAC, and nitric oxide assays. Apoptosis with acridine orange/etho bromide and redox changes was evaluated in the cell lines. The results of toxicity assays showed that the survival rate of the cells were decreased by increasing the concentrations of the peptides (0. 3, 0. 6, 1. 2, and 2. 4 mg/mL). Based on the results of antioxidant activity (TAC, DPPH, No), the Gradual peptides had significantly higher antioxidant activity than Mix peptides (p<0. 05). In addition, the Gradual peptide increased the concentration of nitric oxide compared to the control and Mix groups (p<0. 05). Results also showed that the Gradual peptides reduced the secretion of catalase and GSH enzymes in the cancer cells (p<0. 05). Both types of peptides increased apoptosis in the cancerous cell line and a higher value was observed in bioactive peptides treatments The results of the present study showed that the Pacific white shrimp hydrolysates protein obtained in a progressive rise in temperature showed anti-cancer activities against colon HCT-116cancer cell line.