Application of bacterins and yeast Acremonium dyosporii to protect the larvae of Macrobrachium rosenbergii from vibriosis.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
The giant freshwater prawn Macrobrachium rosenbergii was investigated for its total haemocyte count (THC) based on season, sex, size and feeding rate. The THC, when the prawns were subjected to injections of foreign materials was also investigated. The prawns displayed the highest and lowest THC in autumn and winter respectively, with no significant difference between male and female, or among animals with a body weight range of 7-115 g. The prawns displayed the lowest THC at D3 stage, and the highest in C stage. The prawns displayed the lowest THC when they were fed at 0.1% feeding rate among feeding rates of 0.1%, 0.5%, 1.0% and 1.5% body weight x day(-1). Prawns injected with carbon powder and Enterococcus showed increased THC during the first 6 h. Prawns injected with saline and carbon powder had the lowest THC after 30 h, and recovered to the normal value after 54 h. Prawns injected with Enterococcus showed the lowest THC after 42 h, and showed delayed recovery.
Environmental contamination by heavy metals produced by either anthropogenic or natural activities represents a threat to many species of aquatic animals worldwide. This study investigates the effect of short-term (96 h) exposure to dissolved heavy metals on the number of circulating haemocytes in the shrimp, Palaemon elegans (Rathke). Changes in haemocyte counts were determined in relation to time of exposure and with heavy metal concentration, relating the results to toxicity. It was found that immersion in artificial seawater containing Hg, Cd, Cu, Cr, Zn or Pb caused a decrease in the haemocyte count during the first 8 h exposure, although the haemocyte number returned to the initial (time 0) levels over the following 16 h immersion. In each case, the decrease in circulating haemocyte count induced by these metals was significantly different from the controls. The greatest decrease in haemocyte numbers (haemocytopenia) was induced by Pb, followed, in descending order, by Zn, Hg, Cr, Cu and Cd. The lethal level of haemocytopenia for the shrimps, defined as the number of haemocytes ml remaining in moribund animals (i.e. threshold of mortality) was found to be significantly lower than the levels tolerated by surviving shrimps (i.e. the limit of survival). The percentage of haemocytes remaining in the circulation at the threshold of mortality as a function of the number at time 0 was 56.6 +/- 8.8%. By contrast, the equivalent value for the threshold of survival was 63.7 +/- 12.4%. Importantly, the percentage decrease in haemocyte counts tolerated by P. elegans appears to vary with the metal. Animals treated with Pb or Zn survived with a lower number of circulating haemocytes than animals exposed to the other heavy metals.
Growth of pathogen bacterium. Enterococcus was not affected in tryptic soy broth (TSB) medium containing ammonia-N concentration in the range of 0-5.14 mg l(-1). Giant freshwater prawn Macrobrachium rosenbergii (8-12 g) were challenged with Enterococcus which had been incubated for 24 h in TSB medium containing different concentrations of ammonia-N at 0-5.14 mg l(-1) Cumulative mortality of M. rosenbergii was higher for the bacteria incubated in TSB medium having ammonia-N at 0 and 0.26 mg l(-1), than those incubated in TSB medium having 1.28, 2.57 and 5.14 mg l(-1) ammonia-N after 24 h of challenge. However, cumulative mortality of prawn was significantly higher for the bacteria incubated in TSB medium with no ammonia added after 120 h of challenge. The prawns (8-12 g) were challenged with Enterococcus previously incubated in TSB medium for 24 h, then placed in water having concentrations of ammonia-N at control (0.06 mg l(-1)), 0.55, 1.01, 1.68 and 3.18 mg l(-1). Mortality of prawns increased directly with ammonia-N concentrations after 72 h challenge. The pranws (20-30 g) which had been exposed to control, 0.55, 1.68 and 3.18 mg (-1) ammonia-N for 7 days were examined for the total haemocyte count (THC), differential haemocyte count (DHC), phenoloxidase activity and respiratory burst of haemocytes. Phenoloxidase activity decreased when the prawns were exposed to ammonia-N greater than 0.55 mg l(-1). The respiratory burst increased significantly at 0.55 mg l(-1) but decreased significantly at 1.68 and 3.18mg (-1) ammonia-N. No significant difference in haemocyte count was observed among the prawns at different ammonia-N concentrations. It is suggested that ammonia in water decreases the virulence of Enterococcus, and reduces the immune resistance of M. rosenbergii.
This study compares the in vivo haemocytic response of shrimp, Palaemon elegans (Rathke) to different types of LPS injection. In particular it investigates to what degree and speed the haemocytopenia varies between LPSs from different sources. It further compares the tolerated doses of different LPSs in these animals and finds substantial differences in the various toxicity types. The work then relates this to blood glucose levels and stress-linked variations in glycaemic status. The order of LPS decreasing toxicity determined by LD50 at 96 h was: Salmonella enteritidis, Serratia marcescens, Pseudomonas aeruginosa 10, Escherichia coli K-235 and E. coli 0111:B4. Eyestalkless animals were more sensitive to LPS. The effects of injected LPS on circulating total blood cell count (THC) was tested. The results show that LPS caused a decrease in THC 8 h after injection and then the THC returned to the initial level and this effect depended on the LPS tested. E. coli K-235 was the most effective in causing haemocytopenia followed by E. coli 0111:B4, S. enteritidis, S. marcescens, and P. aeruginosa 10. Moreover, LPS-induced increases in the blood glucose level and the time and dose related curves of response obtained depended on the type of LPS tested. E. coli K-235 LPS was again the most effective in elevating blood glucose followed by E. coli 0111:B4, S. marcescens, S. enteritidis and then P. aeruginosa 10. No significant hyperglycaemia was induced in eyestalkless animals. An inverse order relationship between toxicity (LD50) and stress responses (hyperglycaemia and THC decrease) may suggest a defensive and adaptive role of the latter in occasional septicaemia.
Giant freshwater prawns Macrobrachium rosenbergii (14-19 g) were challenged with Enterococcus (3 x 10(5) cfu prawn(-1)) previously incubated in TSB medium for 24 h, then placed in water having concentrations of dissolved oxygen (DO) at 7.75, 4.75, 2.75 and 1.75 mg l(-1). Onset of mortality occurred after 6 h exposure to 1.75 mg l(-1) DO, and after 12 h exposure to 2.75 mg 1(-1) DO. Cumulative mortality of prawns at 1.75 mg l(-1) DO was significantly higher than that at 4.75 and 2.75 mg l(-1) DO, and cumulative mortality of prawns at 4.75 and 2.75 mg l(-1) DO was significantly higher than that at 7.75 mg l(-1) DO after 96 h. The prawns (20-30 g) which had been placed in water for 0 to 120 h at 7.75, 4.75, 2.75 and 1.75 mg l(-1) DO were examined for the THC (total haemocyte counts), DHC (differential haemocyte counts), phenoloxidase activity, respiratory burst, percentage phagocytosis and clearance efficiency. No significant difference in semi-granular cells and granular cells of prawns was observed among four treatments. The prawns following 120 h exposure to 2.75 mg l(-1) DO decreased significantly the hyaline cells and THC by 39% and 36%, respectively. Phenoloxidase activity and respiratory burst decreased significantly by 33% and 11% when the prawns were exposed to 2.75 mg l(-1) DO after 24 h, respectively. Percentage phagocytosis and clearance efficiency to Enterococcus decreased significantly by 44% and 54% for the prawns following 12 h exposure to 2.75 mg l(-1) DO, respectively. It is concluded that DO as low as 2.75 mg l(-1) and 4.75 mg l(-1) causes depression in immune system of M. rosenbergii, and increases its susceptibility to Enterococcus infection.
The activity of 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) was determined in the hepatopancreas and the ovary of freshwater prawn Macrobrachium rosenbergii, at different stages of life. A uniform level of 17 beta-HSD activity was observed in the hepatopancreas of immature, maturing, matured, and gravid prawns, whereas the activity of this enzyme was found to be higher in the ovary of the maturing prawn only. Gradual increases in the GSI values and ovarian protein content at the different stages of maturity were observed in this animal. Between the two organs, higher activity of 17 beta-HSD was observed in the hepatopancreas of the prawn in the maturing stage. The estradiol-17 beta (E2) level measured by radioimmunoassay showed its peak in both the hemolymph (126.0 +/- 7.0 pg/ml) and the ovary (300.00 +/- 9.0 pg/mg protein) in the maturing prawn only compared to that in immature, matured, and gravid prawns. The hormone level became undetectable in the hemolymph and remained about 10-fold less (30.6 +/- 5.0 pg/mg protein) in the ovary of the gravid prawn in comparison to the prawns in the maturing stage. A parallelism between the nature of 17 beta-HSD activity and the hormone level was observed in the ovary at different stages of life. A dose-dependent stimulation of 17 beta-HSD activity was observed in the hepatopancreas of the maturing prawn after three consecutive injections of 0.25, 0.5, 1.0, and 2.0 micrograms/g of estradiol-17 beta (E2) on the 4th day of treatment compared to the control values.(ABSTRACT TRUNCATED AT 250 WORDS)
Changes in ovarian and hemolymph ecdysteroid concentration and composition during vitellogenesis have been investigated in the freshwater prawn Macrobrachium rosenbergii. Free ecdysteroids (20-hydroxyecdysone and ecdysone) in hemolymph increased in concentration during vitellogenesis from zero at stage 0 to 1.5 ng/ml at stage I to 7.3 ng/ml in mature, stage IV animals. 20-Hydroxyecdysonoic acid (1.2 ng/ml) was detected in the stage IV hemolymph. Ovarian-free ecdysteroid concentration, expressed as nanograms per gram of tissue, fell during vitellogenesis from 83.2 ng/g at stage 0, non-pigmented tissue to 14.2 ng/g at stage IV tissue, being minimal at stage I (6.3 ng/g). However, expression of ovarian free ecdysteroid content as nanograms per ovary revealed a rise from 7.7 ng/ovary at stage 0, nonpigmented tissue to 28.3 ng/ovary at stage IV, again being minimal at stage I (2.0 ng/ovary). 20-Hydroxyecdysonoic acid and ecdysonoic acid were identified at ovarian stages II-III and stage IV.
Injections with different doses (0.1, 0.25, 0.5, 1.0, 2.0, and 4.0 micrograms/g) of estradiol-17 beta (E2), administered three days consecutively, showed a statistically significant increase in mitochondrial Na(+)-K(+)-ATPase, cytosolic malate dehydrogenase, and cytosolic glucose-6-phosphate dehydrogenase activities in a dose-dependent manner in the hepatopancreas of the freshwater prawn (Macrobrachium rosenbergii) on the 4th day of treatment compared to the control values. A lower dose of 0.05 microgram/g was without any effect on these enzyme activities. A uniform increase in the Mg(2+)-ATPase activity was observed after injections with 0.5, 1.0, and 2.0 micrograms/g of E2. Ergosterol, a nonsex steroid did not show any change in the malate dehydrogenase and glucose-6-phosphate dehydrogenase activities on which this compound was tested at a 2.0 micrograms/g dose, compared to the control values. Simultaneous injection of tamoxifen (0.5 microgram/g), an antiestrogenic compound, with E2 (2 micrograms/g) caused inhibition of the E2-induced rise in mitochondrial Na(+)-K(+)-ATPase and cytosolic NADP-linked malate dehydrogenase activities. Conversely, tamoxifen (0.5 and 1.0 microgram/g) behaved as an estrogen agonist to the response (increase) of Mg(2+)-ATPase and cytosolic glucose-6-phosphate dehydrogenase activities. Potentiation of the estrogen effect with tamoxifen (1.0 microgram/g) was observed in these enzyme activities when used simultaneously with E2 (2 micrograms/g). Use of cycloheximide (0.5 mg/liter), a protein synthesis blocker, inhibited the inhibited the E2 (2 micrograms/g)-induced increase in all the enzyme activities studied. The data show specific and prominent subcellular action of estrogen with an indication of its role in energy-dependent ion transport and metabolic activation in hepatopancreas of the freshwater prawn.
The participation of neuroendocrine factors present within the central nervous system in the regulation of hemolymph free amino acid (FAA) concentrations was examined in the freshwater shrimp Macrobrachium olfersii. Test shrimps were injected intramuscularly with homogenates prepared from the eyestalks (ES), ventral nerve cord (VNC), supraesophageal (SEG), or thoracic ganglia (TG) of donor shrimps previously exposed for 6 hr to a high-salinity medium (HSM, 21% salinity). After injection of the homogenate, the shrimps were maintained for up to 6 hr in either freshwater (FW) or HSM. Hemolymph was sampled by cardiac puncture and prepared for reverse phase HPLC, derivatizing the FAA with phenylisothiocyanate. An FAA profile was determined and the [FAA]:[Cl-] ratios for the four FAA present in highest concentration (Gly, Arg, Ala, and Pro for ES and VNC experiments; Glu, Leu, Ala, and Val for SEG and TG experiments) were obtained. Nonparametric analyses revealed specific, notable effects resulting from homogenate injection, e.g., ES homogenate increased [Pro]/[Cl-] ratios in FW-exposed shrimps; SEG homogenate increased [Glu]/[Cl-] and [Val]/[Cl-] ratios in HSM-exposed shrimps; and TG homogenate increased [FAA]/[Cl-] ratios for Glu, Leu, Ala, and Val in HSM-exposed shrimps. Total FAA concentrations decreased after exposure of the shrimps to HSM but were increased by the injection of ES homogenate in FW-exposed shrimps and by TG homogenate in HSM-exposed shrimps. The total [FAA]/[Cl-] ratio was also increased by TG homogenate in HSM-exposed animals. There were no clear effects on [Cl-] alone.(ABSTRACT TRUNCATED AT 250 WORDS)
Eicosanoids are thought to play a role in the regulation of invertebrate reproduction, as they do in vertebrate systems. This was investigated using the previtellogenic ovary of the freshwater prawn Macrobrachium rosenbergii as a biological model. Concentrations of prostaglandin E2 (PGE2), assessed by means of radioimmunoassay, in the previtellogenic ovary (oocyte diameter 20-40 microns) were 32.4 +/- 14.1 pg/mg ovary. Preincubation of the ovary with indomethacin (10 microM) inhibited PGE2 synthesis by 43%. In addition, if indomethacin was added to the culture medium, cAMP levels decreased by 48%. When previtellogenic ovaries were incubated in vitro with PGE2 (0.05 micrograms/ml medium and up), cAMP levels in the tissue homogenate sharply increased. The levels of cAMP rose most significantly (up to 10-fold) when 1-10 micrograms PGE2/ml medium was applied. These results suggest that PGE2, and possibly other prostaglandins, may play a role in the endocrine regulation of crustacean reproduction.
Purification and characterization of the female-specific protein (vitellogenin) from the hemolymph of mature female prawn, Macrobrachium rosenbergii, were the objectives of this study. The comparison of biochemical characteristics between vitellogenin and ovarian vitellin was also conducted. Hemolymph vitellogenin was purified with DEAE, hydroxylapatite, and another DEAE chromatographic column. The specific protein (vitellogenin) was shown in the fractions of chromatographic columns on the basis of ELISA, Western blotting, and immunoprecipitation. A purified vitellogenin was obtained with an apparent molecular weight of 700 kDa as determined by PAGE. The purified vitellogenin was considered as a lipoglycoprotein on the basis of staining data. Three subunits (170, 100, and 89 kDa) in purified vitellogenin and two subunits (100 and 89 kDa) in vitellin were detected with SDS-PAGE. Nondisulfide bonds were found in the binding of polypeptide subunits. Only the 89-kDa subunit was a glycopolypeptide in both vitellogenin and vitellin. The amino acid composition of vitellogenin differed from that of vitellin in a few amino acids. Eight amino acid sequences from the N-terminal end of 89- and 100-kDa subunits were determined and they were identical between vitellogenin and vitellin. Seven amino acid sequence from the N-terminal end of the 170-kDa subunit were also identical to the 100-kDa subunit. Purified vitellogenin was more susceptible to precipitation in a solution with low ionic strength than vitellin. This study suggests a close relationship between vitellogenin and vitellin in M. rosenbergii in their biochemical characteristics.
The phenoloxidase (PO) activity of hemocyte lysate supernatant (HLS) from both tiger shrimp (Penaeus monodon) and giant freshwater prawn (Macro-branchium rosenbergii) was examined by treating HLS with various factors, such as an increase in temperatures from 25 to 70 degrees C, one of four elicitors (beta-1,3-1,6-glucan, zymosan, heat-killed Vibrio cells, and lipopolysaccharide), trypsin, one of three protease inhibitors (soybean trypsin inhibitor, p-nitrophenyl-p'-guanidinobenzoate, and benzamidine), and one of two divalent cations (Mg2+ and Ca2+). The strongest PO activity in both animals was induced at 37 degrees C, while enzyme activity varied according to the concentration of the elicitors or cations added to the HLS samples. The following optimum concentrations were recorded: lipopolysaccharides at 0.5 mg/ml, both beta-glucan and zymosan at 1 mg/ml, and Vibrio cells at 10(6) cells/ml. In addition, for giant freshwater prawn, PO activity increased when HLS was treated with trypsin and decreased when it was separately treated with three protease inhibitors. However, effects of either trypsin or protease inhibitors did not occur in tiger shrimp. Strongest PO activity occurred in HLS treated with 20 mM of either calcium ion or magnesium ion, and the addition of the two cations led to an increase in enzyme activity; a decrease was noted following the treatment with EDTA. Cytochemical analysis revealed that prophenoloxidase system exists in the granulocytes of both tiger shrimp and giant freshwater prawn.
The virulence of two Aeromonas strains (A. veronii and A. caviae) isolated from the hepatopancreas of apparently healthy giant freshwater prawns (Macrobrachium rosenbergii) was compared using a challenge by injections. For the A. veronii strain, challenge with 3.7 x 10(5) cells/g of body weight led to 100% mortality; for the A. caviae strain, 3.8 x 10(6) cells/g produced 100% mortality. The 50% lethal doses (LD50) were 2.0 x 10(3) cells/g for A. veronii and 51.2 x 10(3) cells/g for A. caviae. Use of different culture media (trypticase soy broth vs prawn muscle extract) did not significantly affect the virulence of A. veronii. Injection of a sublethal dose (1 x 10(3) cells/g) of A. veronii led to a significant decrease in the total hemocyte count (THC) between 4 and 24 h after injection. Saline injections also caused a similar though less decrease in THC. In the first 24 h after injection of A. veronii (1 x 10(3) cells/g), the change in the percentages of granulocytes (both granular cells and semigranular cells) in the hemolymph was significantly different. After a significant initial increase, the percentage of hyaline cells fell by a factor of 4, from 9 to 2%. Phenoloxidase activity increased fourfold immediately after injection and returned to preinjection levels at 24 h.
Explore the source record for details and available documents.
Two types of neurosecretory fibers, designated as Type 5 and Type 6 axons, in the sinus gland of the freshwater prawn, Palaemon, establish contact with other neurosecretory axons by means of synaptic junctions. This finding strongly supports the view that release of some neurohormones from the eyestalk may be regulated by neurosecretory neurons through synaptic transmission.
In the medulla terminalis ganglionic X-organ (MTGX) of the eyestalk of the freshwater prawn, Palaemon paucidens, six peptidergic neurosecretory cell types (A-, B-, C-, D-, E-, and F-cells) are distinguishable on the basis of the different morphology of their elementary granules and rough endoplasmic reticulum (rER). All of these cell types seem to correspond to Type-IIIa cells or dispersing Type-IV cells, that have previously been differentiated at the light microscopic level (Hisano, 1974), as judged from the dimensions of their cell bodies and nuclei. Two other peptidergic neurosecretory cell types that are apparently comparable to the Type-II and Type-IIIb cells (Hisano, 1974), respectively, are recognized in parts of the optic ganglia other than MTGX, and these are now designated as G- and H-cells, respectively. All the remaining cell types, designated as Type-I, cluster-forming Type-IV, Type-V and Type-VI cells in our previous light microscopic study, have small cored-vesicles in their cytoplasm. It remains undecided whether these, possibly aminergic, neurons are neurosecretory or not.
By use of a specific antiserum against the molluscan cardio-excitatory tetrapeptide FMRF-amide in combination with the PAP-method it was possible to obtain positive immunocytochemical reactions in several neurosecretory regions of the eyestalk of the prawn Palaemon serratus. FMRF-amide-like material was found in perikarya and nerve fibers of the medulla terminalis and in neurons in the lamina ganglionaris. The immunoreactivity observed in the glandular tissue located at the basal insertion of the eyestalk muscles must be ascribed to a non-specific reaction. The identification of immunopositive nerve fibers, ending on a nerve bundle in the medulla terminalis, and the fact that immunoreactive material was absent in the neurohemal sinus gland seem to indicate a neurotransmitter/neuromodulator function.