Bacteria as Biocontrol Agents for Rearing Larvae of the Crab Portunus trituberculatus

1992 ◽  
Vol 49 (11) ◽  
pp. 2373-2376 ◽  
Author(s):  
Kinya Nogami ◽  
Masachika Maeda
Keyword(s):  
Bacterial Strain ◽  
Growth Stage ◽  
Larval Growth ◽  
Vibrio Anguillarum ◽  
Bacterial Density ◽  
Portunus Trituberculatus ◽  
Bacterial Populations ◽  
Crab Larvae ◽  
Bacterial Assemblages ◽  
Vibrio Spp

Bacterial strain PM-4, isolated from a crustacean culturing pond, improved the growth of crab (Portunus trituberculatus) larvae and repressed the growth of Vibrio anguillarum in seawater. PM-4 was cultured in a large quantity and was added daily for 6 d to 200 m3 of seawater used for culturing crab larvae. Initial bacterial density in the crustacean culture water was 106 cells/mL When bacteria increased to more than 107 cells/mL (at crab larval growth stage zoea II), the protozoan population, primarily flagellates, grew rapidly and reduced bacterial numbers to 106 cells/mL Among the bacterial assemblages monitored, added PM-4 dominated the bacterial populations, i.e. Vibrio spp. numbers decreased or even became undetectable in seawater. Production of crab larvae was greatly increased by adding bacterial strain PM-4 to their culture water.

scholarly journals Biogeochemical controls on the bacterial populations in the eastern Atlantic Ocean

2011 ◽  
Vol 8 (12) ◽  
pp. 3747-3759 ◽  
Author(s):  
S. B. Neogi ◽  
B. P. Koch ◽  
P. Schmitt-Kopplin ◽  
C. Pohl ◽  
G. Kattner ◽  
...  
Keyword(s):  
Surface Layer ◽  
Atlantic Ocean ◽  
Chlorophyll A ◽  
Bacterial Abundance ◽  
Aquatic Organisms ◽  
Bacterial Populations ◽  
Organic C ◽  
Cultivable Bacteria ◽  
Eastern Atlantic Ocean ◽  
Vibrio Spp

Abstract. Little is known about bacterial dynamics in the oligotrophic ocean, particularly about cultivable bacteria. We examined the abundance of total and cultivable bacteria in relation to changes in biogeochemical conditions in the eastern Atlantic Ocean with special regard to Vibrio spp., a group of bacteria that can cause diseases in human and aquatic organisms. Surface, deep water and plankton (<20 μm, 20–55 μm and >55 μm) samples were collected between 50° N and 24° S. Chlorophyll-a was very low (<0.3 μg l−1) in most areas of the nutrient-poor Atlantic, except at a few locations near upwelling regions. In surface water, dissolved organic carbon (DOC) and nitrogen (DON) concentrations were 64–95 μM C and 2–10 μM N accounting for ≥90 % and ≥76 % of total organic C and N, respectively. DOC and DON gradually decreased to ~45 μM C and <5 μM N in the bottom water. In the surface layer, culture independent total bacteria and other prokaryotes represented by 4´-6-diamidino-2-phenylindole (DAPI) counts, ranged mostly between 107 and 108 cells l−1, while cultivable bacterial counts (CBC) and Vibrio spp. were found at concentrations of 104–107 and 102–105 colony forming units (CFU) l−1, respectively. Most bacteria (>99 %) were found in the nanoplankton fraction (<20 μm), however, bacterial abundance did not correlate with suspended particulates (chlorophyll-a, particulate organic C [POC] and N [PON]). Instead, we found a highly significant correlation between bacterial abundance and temperature (p < 0.001) and a significant correlation with DOC and DON (p < 0.005 and <0.01, respectively). In comparison to CBC and DAPI-stained prokaryotes, cultivable Vibrio showed a stronger and highly significant correlation with DOC and DON (p < 0.0005 and p < 0.005, respectively). In cold waters of the mesopelagic and abyssal zones, CBC was 50 to 100-times lower than in the surface layer; however, cultivable Vibrio spp. could be isolated from the bathypelagic zone and even near the seafloor (average ~10 CFU l−1). The depth-wise decrease in CBC and Vibrio coincided with the decrease in both DOC and POC. Our study indicates that Vibrio and other bacteria may largely depend on dissolved organic matter to survive in nutrient-poor oceanic habitats.

Characteristics and Identification of Pasteurella and Vibrio Species Pathogenic to Fishes using API-20E (Analytab Products) Multitube Test Strips

1982 ◽  
Vol 39 (12) ◽  
pp. 1725-1729 ◽  
Author(s):  
Michael L. Kent
Keyword(s):  
Vibrio Anguillarum ◽  
Diagnostic Procedures ◽  
Blood Agar ◽  
Marine Agar ◽  
Biochemical Characteristics ◽  
Test Strips ◽  
Fish Pathology ◽  
Fish Bacteria ◽  
Vibrio Spp

Morphological, cultural, and biochemical characteristics of Pasteurella spp. and Vibrio spp. pathogenic to fishes are investigated. Vibrio anguillarum, V. ordalii, V. alginolyticus, V. parahaemolyticus, an unidentified Vibrio sp. (AN1K), Pasteurella piscicida, and P. multocida were cultured on API-20E multitube test strips (Analytab Products) and in Baumann's marine media with similar results. The API-20E Profile Index was not useful for classification of fish bacteria studied and, using the index. Vibrio sp. AN1K was misidentified as P. multocida. Bacteria studied were also grown on Marine Agar (Difco) and on blood agar at 25 and 37 °C. On blood agar at 37 °C some vibrios resembled pasteurellas as a result of pleomorphism and lack of motility. Simple diagnostic procedures for identifying Pasteurella spp. and Vibrio spp. associated with fishes using the API-20E with modifications are presented.Key words: Pasteurella, Vibrio, characteristics, Analytical Profile Index, fish pathology

scholarly journals Συσχέτιση περιβαλλοντικών παραμέτρων με την εμφάνιση ασθενειών στο εκτρεφόμενο λαβράκι Dicentrarchus labrax, L. 1758 και πρόληψη των ασθενειών αυτών

2019 ◽  
Author(s):  
Ευθύμιος Σπίνος
Keyword(s):  
Vibrio Anguillarum ◽  
Dicentrarchus Labrax ◽  
Photobacterium Damselae ◽  
Vibrio Spp

Στην Ελλάδα οι πιο σημαντικές βακτηριακές ασθένειες που πλήττουν τις ιχθυοκαλλιέργειες είναι η δονακίωση που προκαλείται από το βακτήριο Listonella (Vibrio) anguillarum και η φωτοβακτηριδίαση που προκαλείται από το βακτήριο Photobacterium damselae subsp. piscicida (Phdp) και το πιο ευαίσθητο ψάρι σε αυτές είναι το λαβράκι. Άλλη σημαντική ασθένεια είναι η ιογενής εγκεφαλοπάθεια και αμφιβληστροειδοπάθεια, που οφείλεται στη μόλυνση των ψαριών από Betanoda-ιούς και το χειμερινό σύνδρομο που σχετίζεται με τη μείωση της θερμοκρασίας τους χειμερινούς μήνες και είναι ασθένεια που προσβάλλει κυρίως την τσιπούρα. Η διατριβή πραγματεύτεται τη συσχέτιση της πιθανότητας εμφάνισης των τεσσάρων κυριότερων ασθενειών του εκτρεφόμενου λαβρακιού και της τσιπούρας με τις φυσικοχημικές παραμέτρους του θαλασσινού νερού δύο μονάδων ιχθυοκαλλιεργειών στον Κόλπο Αργοστολίου και συγκεκριμένα της θερμοκρασίας, της αλατότητας, του διαλυμένου οξυγόνου και του pH, χρησιμοποιώντας δεδομένα τέτοιων παραμέτρων και ασθενειών από το 2011 έως το 2015. Έχουν επίσης συμπεριληφθεί δεδομένα χρονοσειρών θρεπτικών αλάτων, χλωροφύλλης α, μικροβιολογικών παραμέτρων και δεδομένα διαχείρισης για το χρονικό διάστημα 1994-2013. Τα αποτελέσματα έδειξαν ότι η θνησιμότητα εξαιτίας της δονακίωσης σχετίζεται σημαντικά με τη μείωση του pH του νερού, η θνησιμότητα εξαιτίας της φωτοβακτηριδίασης σχετίζεται έντονα με την αύξηση της θερμοκρασίας και της αλατότητας του νερού, η θνησιμότητα από την ιογενή εγκεφαλοπάθεια-αμφιβληστροειδοπάθεια σχετίζεται ευθέως με μειούμενη θερμοκρασία μετά από αύξησή της και η θνησιμότητα από το χειμερινό σύνδρομο συμπίπτει με χαμηλές θερμοκρασίες. Η μείωση του διαλυμένου οξυγόνου λειτουργεί συνεργιστικά με τις άλλες παραμέτρους και πυροδοτεί την εμφάνιση και των τεσσάρων ασθενειών. Ο Κόλπος Αργοστολίου είναι ένα οικοσύστημα που κατατάσσεται από ολιγότροφο όταν η θερμοκρασία είναι υψηλή και μεσοτροφικό όταν είναι χαμηλή. Υπάρχει σχετικά έντονη παρουσία μικροοργανισμών στο νερό του Κόλπου Αργοστολίου που οφείλεται κυρίως σε αστικά λύματα. Οι υψηλές τιμές κολοβακτηριδίων σ’αυτό το παράκτιο οικοσύστημα δείχνουν ότι θα υπάρχουν και άλλοι παθογόνοι μικροοργανισμοί οι οποίοι δυνητικά μπορεί υπό κατάλληλες συνθήκες να προκαλέσουν ασθένειες στα ψάρια.Επίσης, μελετήθηκε η πρόληψη των ασθενειών του εκτρεφόμενου λαβρακιού μέσω εφαρμογής εμβολιασμών και σύγκρισης της αποτελεσματικότητας δύο ενέσιμων διδύναμων (Vibrio spp. & Photobacterium) εμπορικών εμβολίων (Alphaject 2000 και Aquavac) σε πραγματικές και πειραματικές, ελεγχόμενες συνθήκες (ενυδρεία), όσον αφορά στην προστασία από φυσικές και πειραματικές λοιμώξεις, στην ανοσοαπόκριση των ψαριών, στην ανάπτυξη συμφύσεων στην κοιλιακή κοιλότητα στο σημείο της έγχυσης και στην ανάπτυξη των ψαριών. Τα δύο εμπορικά εμβόλια που μελετήθηκαν προστατεύουν σημαντικά τα ψάρια έναντι των λοιμώξεων με L. anguillarum O1 και Phdp σε σύγκριση με την ομάδα μαρτύρων (control). Από τα δύο εμπορικά εμβόλια που χρησιμοποιήθηκαν, το ελαιώδες ανοσοενισχυμένο (Alphaject 2000), φαίνεται να προσφέρει μεγαλύτερη προστασία σε σχέση με το υδατοδιαλυτό (Aquavac) και προκάλεσε την παραγωγή σημαντικά υψηλότερων ειδικών τίτλων αντισωμάτων έναντι των δύο παθογόνων και τα ευρήματα αυτά σχετίζονται με την παρατηρούμενη συνολική απόδοση αυτού του εμβολίου κατά τη διάρκεια των δοκιμών αποτελεσματικότητας. Οι ειδικοί τίτλοι αντισωμάτων έναντι του Phdp που προκαλούνται από τις δύο εμβολιασμένες ομάδες ήταν υψηλότεροι σε σύγκριση με τους ειδικούς τίτλους αντισωμάτων έναντι του L. anguillarum O1. Το ανοσοενισχυμένο εμβόλιο προκάλεσε τοπικές παρενέργειες στο σημείο της κοιλιακής κοιλότητας που διοχετεύθηκε, ενώ το υδατοδιαλυτό προκάλεσε μόνο μία ήπια τοπική φλεγμονώδη αντίδραση. Τα εμβολιασμένα ψάρια που συμμετείχαν στα πειράματα εμφάνισαν καλύτερη ανάπτυξη σε σχέση με τα ψάρια μάρτυρες. Ο ειδικός ρυθμός αύξησης (SGR) για ολόκληρη την πειραματική περίοδο ήταν χαμηλότερος για τις δύο ομάδες των ψαριών μαρτύρων (0,22 για το μικρό και 0,26 για το μεσαίο μέγεθος). Ο συντελεστής μετατρεψιμότητας της τροφής (FCR), από έξι (6) συνολικά παρτίδες ψαριών (2 μεσαίου και 2 μικρού μεγέθους ψάρια για κάθε εμπορικό εμβόλιο και μεσαίου και μικρού μεγέθους ψάρια μάρτυρες) στα μεσαίου μεγέθους ψάρια που εμβολιάστηκαν με το εμβόλιο Aquavac ήταν χαμηλότερος (0,60), ενώ τα μικρού μεγέθους ψάρια που εμβολιάστηκαν με το εμβόλιο Aquavac (0,74), τα μικρού και μεσαίου μεγέθους ψάρια που εμβολιάστηκαν με το εμβόλιο Alphaject 2000 (0,82 και 0,74) και οι ομάδες με τα μικρού και μεσαίου μεγέθους ψάρια μάρτυρες (0,78 και 0,79) είχαν σχετικά υψηλό FCR. Η παρούσα διδακτορική διατριβή είναι πρωτότυπη και θα συμβάλλει σημαντικά στην κατανόηση των οικοσυστημάτων στα οποία έλαβε χώρα, καθώς και στην πρόληψη προσβολής των εκτρεφόμενων ψαριών από τις σημαντικότερες ασθένειες.

Biocontrol method in aquaculture for rearing the swimming crab larvae Portunus trituberculatus

1997 ◽  
pp. 291-295 ◽  
Author(s):  
Kinya Nogami ◽  
Katsuyuki Hamasaki ◽  
Masachika Maeda ◽  
Kazutsugu Hirayama
Keyword(s):  
Portunus Trituberculatus ◽  
Swimming Crab ◽  
Crab Larvae

Influence of zinc on bacterial populations and their proteolytic enzyme activities in freshwater environments: a cross-site comparison

2016 ◽  
Vol 62 (4) ◽  
pp. 320-328 ◽  
Author(s):  
Lauren Rasmussen ◽  
Ola A. Olapade
Keyword(s):  
Enzyme Activities ◽  
Proteolytic Enzyme ◽  
Hydrolytic Enzyme ◽  
Aquatic Environments ◽  
Time Intervals ◽  
Bacterial Populations ◽  
Bacterial Assemblages ◽  
Role Of Zn ◽  
Freshwater Environments

Temporal responses of indigenous bacterial populations and proteolytic enzyme (i.e., aminopeptidase) activities in the bacterioplankton assemblages from 3 separate freshwater environments were examined after exposure to various zinc (Zn) concentrations under controlled microcosm conditions. Zn concentrations (ranging from 0 to 10 μmol/L) were added to water samples collected from the Kalamazoo River, Rice Creek, and Huron River and examined for bacterial abundance and aminopeptidase activities at various time intervals over a 48 h incubation period in the dark. The results showed that the Zn concentrations did not significantly influence total bacterial counts directly; however, aminopeptidase activities varied significantly to increasing zinc treatments over time. Also, analysis of variance and linear regression analyses revealed significant positive relationships between bacterial numbers and their hydrolytic enzyme activities, suggesting that both probably co-vary with increasing Zn concentrations in aquatic systems. The results from this study serve as additional evidence of the ecological role of Zn as an extracellular peptidase cofactor on the dynamics of bacterial assemblages in aquatic environments.

scholarly journals The influence of wet feed distribution on the density, growth rate and growth variability of Tenebrio molitor

2020 ◽  
pp. 1-10
Author(s):  
D. Deruytter ◽  
C.L. Coudron ◽  
J. Claeys
Keyword(s):  
Growth Rate ◽  
Growth Stage ◽  
Larval Growth ◽  
Tenebrio Molitor ◽  
Unequal Distribution ◽  
Growth Variability ◽  
Density Growth ◽  
Food And Feed ◽  
Mealworm Larvae

Mealworm larvae have the potential to be a future food and feed. One of the difficulties in rearing mealworms efficiently, is their need for both dry and wet feed. Extensive research has been done on dry feed and distributing this feed is easy with the existing technology. However, the wet feed (frequently chopped up vegetables) comes with several challenges. The nature of the wet feed (neither solid nor liquid) complicates automation, making manual feeding still the norm in many farms. This may result in an unequal distribution of the wet feed. The goal of this study was to assess the influence of distance to the wet feed (substituted by agar) on density, growth rate and growth rate variability of mealworm larvae. The entire larval growth stage was assessed from less than 1 mg up to more than 100 mg, as differences in mobility were expected for different sized larvae. The results indicate that the distribution of the agar plays a major role in the distribution and growth of the larvae, with less larvae and a decrease in growth rate observed when the agar was more than 5 to 10 cm away from the larvae. Few mealworms were found more than 15 cm from the agar, and their growth was inhibited resulting in a biomass up to 150 times lower than near the agar. The effects were mainly observed in larvae weighing less than 30 mg, heavier mealworms were mobile enough to crawl to and from the agar. Based on the results, and in order to ensure that all larvae sizes grow equally well and are well distributed in the crate, we strongly advise against distances of 10 cm or more and we recommend the placement of wet feed within 5 cm from the larvae.

scholarly journals The disproportionate effect of drift on a hypervariable master regulator of density

2020 ◽  
Author(s):  
Alexis Bénard ◽  
Hélène Henri ◽  
Camille Noûs ◽  
Fabrice Vavre ◽  
Natacha Kremer
Keyword(s):  
Copy Number ◽  
Molecular Mechanisms ◽  
Fruit Fly ◽  
Genomic Region ◽  
Host Population ◽  
Bacterial Density ◽  
Bacterial Populations ◽  
Density Regulation ◽  
Efficiency Of Selection ◽  
Host Influence

AbstractSymbiosis is a continuum of long-term interactions ranging from mutualism to parasitism, according to the balance between costs and benefits for the protagonists. The density of endosymbiont density is in both cases a key factor that determines both the transmission of symbiont and the host extended phenotype and is thus tightly regulated within hosts. However, the evolutionary and molecular mechanisms underlying bacterial density regulation are currently poorly understood. In this context, the symbiosis between the fruit fly and its intracellular bacteria Wolbachia (wMelPop strain) is particularly interesting to study. Although vertically-transmitted, the symbiont is pathogenic, and a positive correlation between virulence and wMelPop density is observed. In addition, the number of repeats of a bacterial genomic region -Octomom- varies between individuals, but most likely also within them, and is positively correlated to the Wolbachia density. Such genetic heterogeneity within the host could promote conflicts between partners by increasing within-host competition between symbiont genotypes through a process analogous to the tragedy of the common. To characterize the determinisms at play in the regulation of bacterial density, we first introgressed wMelPop in different genetic backgrounds of D. melanogaster. We found different density levels and Octomom copy numbers in each host lineage, suggesting a host influence on density regulation through Octomom copy number selection. To confirm this hypothesis, we performed new replicated introgressions on the two Drosophila populations that exhibited the most extreme density levels. However, we found no evidence of host influence on density regulation. Instead, we found instability in infection patterns across generations, which rather suggests an influence of drift. Moreover, using reciprocal crosses with the two extreme lineages, we confirmed the absence of host regulation on density levels and Octomom copy number, and a strong influence of drift. We then discuss how drift, both on the symbiont population during transmission and on the host population, could limit the efficiency of selection in such a symbiotic system, and the consequences of drift on the regulation of density and composition of bacterial populations.

scholarly journals Exploring the Links between Natural Products and Bacterial Assemblages in the SpongeAplysina aerophoba

2010 ◽  
Vol 77 (3) ◽  
pp. 862-870 ◽  
Author(s):  
Oriol Sacristán-Soriano ◽  
Bernard Banaigs ◽  
Emilio O. Casamayor ◽  
Mikel A. Becerro
Keyword(s):  
Natural Products ◽  
High Performance ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Strong Relationship ◽  
Rrna Gene ◽  
Benthic Organism ◽  
Bacterial Populations ◽  
Gradient Gel Electrophoresis ◽  
Aplysina Aerophoba ◽  
Bacterial Assemblages

ABSTRACTThe spongeAplysina aerophobaproduces a large diversity of brominated alkaloids (BAs) and hosts a complex microbial assemblage. Although BAs are located within sponge cells, the enzymes that bind halogen elements to organic compounds have been exclusively described in algae, fungi, and bacteria. Bacterial communities withinA. aerophobacould therefore be involved in the biosynthesis of these compounds. This study investigates whether changes in both the concentration of BAs and the bacterial assemblages are correlated inA. aerophoba. To do so, we quantified major natural products using high-performance liquid chromatography and analyzed bacterial assemblages using denaturing gradient gel electrophoresis on the 16S rRNA gene. We identified multiple associations between bacteria and natural products, including a strong relationship between aChloroflexiphylotype and aplysinamisin-1 and between an unidentified bacterium and aerophobin-2 and isofistularin-3. Our results suggest that these bacteria could either be involved in the production of BAs or be directly affected by them. To our knowledge, this is one of the first reports that find a significant correlation between natural products and bacterial populations in any benthic organism. Further investigating these associations will shed light on the organization and functioning of host-endobiont systems such asAplysina aerophoba.

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