Evaluating the effect of temperature on Penaeus vannamei culture in a heterotrophic system and experimentally infected with the infectious myonecrosis virus

Does the heterotrophic system influence the cellular immune response of Litopenaeus vannamei shrimp? In vitro phagocytosis indices and superoxide anion production comparisons

The effect of different acclimation temperatures on the prophenoloxidase system and other defence parameters in Litopenaeus vannamei

Infectious myonecrosis virus (IMNV) is a significant pathogen affecting Litopenaeus vannamei, causing high mortality and substantial economic losses in shrimp aquaculture. Conventional chemotherapeutics have limited efficacy and raise environmental concerns. This study explores the immunostimulatory potential of squid (Loligo spp.) ink powder as a natural dietary supplement to enhance the nonspecific immune responses in L. vannamei and mitigate IMNV-associated pathology. A completely randomized design was employed, with five groups: a negative control (healthy shrimp), a positive control (IMNV-infected), and three treatment groups that received squid ink powder at 400, 500, and 600 mg/kg feed, respectively. The feed was administered before and after IMNV immersion challenge. Immune parameters assessed included total hemocyte count (THC), differential hemocyte count (DHC), respiratory burst (RB), phenoloxidase (PO), superoxide dismutase (SOD), phagocytic activity, and ribonucleotide reductase (RR) expression. Statistical analysis was conducted using a one-way analysis of variance with Duncan's post hoc test. The 500 mg/kg dose of squid ink powder significantly enhanced shrimp immunity post-IMNV challenge. This treatment yielded the highest THC (6 × 105 cells/mL), RB (1.13 optical density [OD]), SOD (0.98 units/mL), PO (0.619 OD), and phagocytic activity. A marked reduction in RR enzyme expression was observed, indicating effective viral suppression. DHC analysis revealed elevated granulocyte and semi-granulocyte counts, suggesting heightened immunological activity. Water quality parameters remained within acceptable aquaculture limits, and proximate analysis confirmed an improvement in protein content in the feed following supplementation. Squid ink powder at 500 mg/kg feed significantly enhances the non-specific immune system in L. vannamei and reduces IMNV-induced pathology. This natural additive offers a promising, sustainable alternative to synthetic immunostimulants in shrimp aquaculture.

The main causes of death of pacific white shrimp in aquaculture are diseases. One effort to control deseases by improving the defense ability of shrimp body against disesases and optimizing water quality during farming through the application of a new aquaculture technology called Immuno-Probiocirculation System (SI-PBR). This research aimed to analyze immune response on Total Haemocyte Count (THC) and Differential Haemocyte Count (DHC), parasitic infestation on pacific white shrimp in many ages, survival rate of pacific white shrimp during farming period for 90 days in SI-PBR. The results of this research showed that the lowest parasitic infestation (Zoothamnium penaei) is 12.46 % that happened on 90-days-old shrimp in SI-PBR pond, while the highest infestasion is on the shrimp not given SI-PBR, reaching 54.65 %. In addition, the immune response (THC and DHC) also increased. The highest survival rate discovered in 90 days shrimp farming is 80% using SI-PBR. This is higher than the pond without SI-PBR, which is 22 %. Therefore, SI-PBR in shrimp farming in tradisional ponds is able to increase immune response, survival rate, and is also able to decrease parasitic infestation during 90 days of farming.

Immune resistance of white shrimp against disease can be enhanced through the administration of immunostimulant. Some of sea microalgae extracts has been proved trough examination to be able to stimulate immune system of shrimp. The objective of this study is to know immune response of Litopenaeus vannamei injected with hot water extract Chaetoceros ceratosporum (HWEC) doses of 5, 10, 15 and 20 µg·g -1 body weight (BW) against Infectious Myonecrosis (IMNV) virus infection. The findings show that C . ceratosphorum administration can enhance immune response of L. vannamei infected by Infectious Myonecrosis virus, indicated by the increasing number of hemocytes (THC), total protein plasma (TPP), phenolokxidase (PO) activity, and respiratory burst (RB) activity. Highest immune response is achieved by injection dose of 15 µg·g -1 shrimp body weight. The increase of shrimp immune response leads to the increase of shrimp immune system against IMNV infection, so the survival rate of L. vannamei infected by IMNV is higher than positive control and similar to those of negative control.

Alterations in the hemocyte population ofPeriplaneta americana (L.) during starvation and desiccation were studied for 11 days. Total hemocyte count showed increasing trend throughout the starvation period. Changes in differential hemocyte count were evident. Plasmatocytes and granulocytes decreased marginally. Increase in coagulocyte count occurred from 6th day onwards. Two-fold increase in the total hemocyte and differential count was pronounced during subsequent days. During the combined stress period total hemocyte count was significantly higher. Differential hemocyte count was also altered. Degenerative changes set in during late phases of the experiment. The causal factors for such changes in hemocyte population under experimental stress are discussed.

Physiological and biochemical responses of Mediterranean green crab, Carcinus aestuarii, to different environmental stressors: Evaluation of hemocyte toxicity and its possible effects on immune response

DAO Diseases of Aquatic Organisms Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials DAO 31:147-153 (1997) - doi:10.3354/dao031147 Use of a clinical cell flow cytometer for differential counts of prawn Penaeus monodon haemocytes Leigh Owens*, Antoinette O'Neill Department of Microbiology and Immunology, PO James Cook University of North Queensland 4811, Australia *E-mail: leigh.owens@jcu.edu.au Flow cytometry (FC) has been used extensively for monitoring human blood cell populations and it would be useful if this technology could be applied to the analysis of prawn haemocytes. This paper shows that the Cell-Dyn 3000 flow cytometer can distinguish haemocyte types from Penaeus monodon and then describes the range of haemocyte counts within normal prawns. The total haemocyte count was 23.3 × 106 cells ml-1 using a haemocytometer and 21.0 × 106 cells ml-1 with the FC. With light microscopy, nongranular, small-granular and large-granular haemocytes were 82.7 ± 14, 15.6 ± 17, and 1.7 ± 2% respectively of the cell types, whilst with FC, the proportions were 82.6 ± 17, 14.5 ± 15, and 2.9 ± 3% respectively. Neither age, weight, carapace length nor population source had any significant effect (p > 0.05) on total or differential haemocyte counts. However, sex had a significant effect (p < 0.05) and once sexual dimorphism, as measured by total length, had occurred in the prawn population, females showed increased nongranular haemocyte counts (F = 4.56, df = 1,39, p < 0.05) and, consequently, total haemocyte counts (F = 4.60, df = 1,39, p < 0.05). The third sequential bleeding of prawns (0.1 ml of haemolymph bleed-1) produced a significant decrease in total haemocyte numbers with proportional increases in granular haemocytes. Penaeus monodon · Flow cytometry · Haemocyte counts · Disease studies Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in DAO Vol. 31, No. 2. Publication date: November 20, 1997 Print ISSN:0177-5103; Online ISSN:1616-1580 Copyright © 1997 Inter-Research.

Immunological lectins in shrimp Penaeus vannamei challenged with infectious myonecrosis virus (IMNV) under low-salinity conditions

Nonylphenol (NP), an environmental hormone has garnered great concern in recent ecotoxicological research because of its estrogenic properties. In order to understand the effects of NP on aquacultured shrimp, this study evaluated NP bioaccumulation, immune response (including the hemocyte count, phenoloxidase (PO) activity, respiratory bursts, the antioxidant status, phagocytic activity and clearance efficiency), and disease resistance of shrimp after being fed NP-containing diets at the concentration of 0 (control), 10, 50, and 100 μg NP/kg diet. The NP bioaccumulation assay showed that shrimp fed a diet containing NP at the level of 100 μg NP/kg diet for 30 days had NP bioaccumulation of 600.78 μg NP/ g shrimp, but no NP bioaccumulation was found in shrimp fed diets containing NP at up to 50 μg NP/ kg diet. After feeding the NP-containing diet for 30 days, 11.1%, 15.6%, and 17.8% of shrimp had died in treatments with 10, 50, and 100 μg NP/kg diet, respectively, while control shrimp were all alive. No significant changes in the total hemocyte count, differential hemocyte count, or PO activity were found in any shrimp. However, PO activity per granular cell of shrimp treated with oral NP had significantly decreased by the 28th day. Oxidative stress was observed in this study as based on the increased respiratory bursts, glutathione peroxidase activity, and glutathione reductase. Although no significant difference in superoxide dismutase activity was found in any shrimp, the phagocytic activity of shrimp fed the 100 μg NP/kg diet for 28 days, and clearance efficiency of shrimp against ＂Vibrio alginolyticus＂ decreased in shrimp treated with NP at concentrations of 10-100 μg NP/kg diet, which corresponded to mortalities of NP-treated shrimp after being injected with the pathogen, ＂V. alginolyticus＂. It is, therefore, considered that white shrimp being fed with NP containing diets might suppress their immunity and disease resistance.

In this study, we investigated the effects of low salinity (26 and 21) on the prophenoloxidase (proPO) system and related defence parameters in the shrimp Litopenaeus vannamei. The results showed that low salinity induced a significant increase of dopamine (DA) concentration in haemolymph at 6 h of the experiment; on the other hand, total haemocyte count (THC), differential haemocyte count (DHC) and PO activity decreased over time to the lowest level at 24 h and remained low thereafter. Serine Protease (SP) and Proteinase Inhibitor (PI) activity in the two lower salinity treatments decreased to the lowest level at 12 and 24 h, respectively, and both recovered to the control level at 72 h. In contrast, α2- macroglobulin (α2M) activity in the two lower salinity treatments peaked at 24 h and then decreased to the control level at 72 h. Therefore, it may be concluded that stress-induced DA plays an important temporary role in neurotransmission and causes immune response in L. vannamei in adapting to salinity changes.

Enumeration of invertebrate hemocytes is a potentially powerful tool for the determination of physiological effects of extrinsic stressors, such as hypoxia, disease, and toxicant exposure. A detailed flow cytometric method of broad application was developed for the objective characterization and enumeration of the hemocytes of New Zealand freshwater crayfish Paranephrops planifrons for the purpose of physiological health assessment. Hemocyte populations were isolated by flow cytometric sorting based on differential light scatter properties followed by morphological characterization via light microscopy and software image analysis. Cells were identified as hyaline, semigranular, and granular hemocytes based on established invertebrate hemocyte classification. A characteristic decrease in nuclear size, an increase in granularity between the hyaline and granular cells, and the eccentric location of nuclei in granular cells were also observed. The granulocyte subpopulations were observed to possess varying degrees of granularity. The developed methodology was used to perform total and differential hemocyte counts from three lake populations and between wild and captive crayfish specimens. Differences in total and differential hemocyte counts were not observed among the wild populations. However, specimens held in captivity for 14 d exhibited a significant 63% reduction in total hemocyte count, whereas the relative hemocyte proportions remained the same. These results demonstrate the utility of this method for the investigation of subacute stressor effects in selected decapod crustaceans.

The boxwood moth, Cydalima perspectalis Walker (Lepidoptera: Crambidae), as invasive specialist species in Iran has caused considerable damage in endemic forest stands of Buxus hyrcana Pojark since 2016. Host plant species can alter herbivore–plant interactions through the quantitative and qualitative changes of hemocytes even within a specialist herbivore. To determine the hemocyte variations on different host plants across larval development, the third and sixth instar larvae of C. perspectalis fed on B. hyrcana (native boxwood) and B. microphylla Sieb. and Zucc. (introduced nonnative boxwood) were compared. Total (THC) and differential (DHC) hemocyte count were determined using light, phase‐contrast, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Based on results, six types of hemocytes were recognized in hemolymph including prohemocytes (PRs), plasmatocytes (PLs), granulocytes (GRs), oenocytoides (OEs) and spherulocytes (SPs) as well as unknown elongated quadrangular cells (elongocytes [ELs], the term has been first employed here) with obvious and distinguishable nuclei which were observed by the SEM and TEM microscopy. The ELs were rectangular or trapezoidal in shape, and the largest cells in hemolymph—their length varied from 14.00 to 15.73 μm. Our results showed that the total number of hemocytes (THC) significantly increased across larval development. Moreover, host plant species significantly affected total hemocyte count where the THC of sixth instar larvae on B. microphylla (2561.00 ± 10.60 cell/mm3) was significantly higher than on B. hyrcana (2440.00 ± 51.50 cell/mm3). The differential hemocyte count (DHC) profile study showed that GRs along with PLs were the most abundant cells in the hemolymph irrespective of larval instar and host plant species. Furthermore, the GRs% and ELs% increased throughout the larval development on both host plants, while a significant reduction of PLs% was recorded from third instar to sixth instar during the larval stage on two Buxus species. Apart from larval instar, host plant species had a significant effect on DHC of C. perspectalis. Despite higher total hemocyte number when fed on B. microphylla, the PLs% and ELs% were significantly higher in sixth‐instar larvae fed on B. hyrcana compared with B. microphylla. Oppositely, the percentage of GRs was 17% less in larvae reared on B. hyrcana than on B. microphylla. As hemocyte types are responsible for different immune functions, these findings on instar‐ and host plant‐dependent variation in their relative abundance would be critical to understand the immune response of this specialist herbivore.

Kijing Taiwan ( Anodonta woodiana ) is found in water with muddy substrate. Kijing Taiwan lives in bottom waters and is relatively settled. Kijing Taiwan is a filter feeder organism that can filter water and is able to survive in polluted environment, so it can be used as a bio-indicator of a water body. The study was conducted in the Public Hatchery Unit (UPR) Sumber Mina Lestari. Profile hemocytes in Taiwan Kijing influenced by environment pollution inducer among others. Hemocytes were observed consisting of Total Haemocyte Count (THC) and Differential Haemocyte Count (DHC). The results show that the profile of hemocytes (THC and DHC) of Kijing Taiwan is not polluted. Results from aquaculture pond water quality measurements indicate that the indicators of the water quality i.e. temperature, pH, dissolved oxygen, and ammonia are still within normal limits. However, in TOM test, BOD and soil organic matter has exceeded the normal limits. The existence of organic matter became the medium of life for Kijing Taiwan, due to its role as a biofilter among other organic materials. Keywords: Hemocytes Profile, Kijing Taiwan, Water Quality.

This study aimed to evaluate the application of synbiotic containing multispecies of probiotics with different cell densities in white shrimp rearing against infectious myonecrosis virus (IMNV) and Vibrio parahaemolyticus coinfection. This study used a completely randomized design with five treatments and three replications. One additional replication of each treatment was provided for the lethal sampling. Pacific white shrimp were fed with three dosages of synbiotic multispecies for 30 days, namely 103 CFU mL−1 (Sin 3), 106 CFU mL−1 (Sin 6), and 109 CFU mL−1 (Sin 9), and the controls without synbiotic administration consisted of the positive control (K +) and the negative control (K −). Pacific white shrimp from all treatments, except for the K − , were challenged with IMNV a dose of 100 µL and 106 CFU mL−1 V. parahaemolyticus, injected intramuscularly. Infected Pacific white shrimp showed clinical signs like anorexia, melanosis, empty gut, colorless hepatopancreas, and white necrotic areas in striated skeletal muscles, especially of the distal abdominal segments and uropod. The results showed that administration of synbiotic for 30 days resulted in higher immune parameters, such as total hemocyte count (THC), phenoloxidase activity (PO), respiratory bursts (RB), and total viable bacterial count (TBC) compared to K + /K − . After coinfection, they showed significantly higher levels for THC, PO, RB, gene expression prophenoloxidase (ProPO), and lipopolysaccharide and β-1.3-glucan-binding protein (LGBP), better clinical signs, and lower mortalities. Sin 9 treatment significantly showed the highest survival rate (SR) compared to the other treatments.