Larval Rearing and Post larval Production of Ganga River Shell Fishes Macrobrachium gangeticum and Macrobrachium malcolmsonii

As part of an effort to use biological control against human schistosomiasis, post-larval production of the prawn Macrobrachium vollenhovenii was carried out in a hatchery. This species is a freshwater native and is fond of mollusks, intermediate hosts of schistosomes that transmit human diseases in the wild. The larval production of this species occurred in six (06) tanks - two 200 L and four 600 L. The management of brood stock took place in fresh water, with a ratio of one male to four females. Each fertilized female produced thousands of eggs attached to the abdomen until hatching about two weeks later. The larvae resulting from this reproduction were raised to the post-larval stage in brackish water at a salinity of 15 ppt. The larvae must undergo a molt between each stage. We identified 15 morphological stages between stage 1 and the post-larval stage. The duration from stage 1 until onset of the first post-larval stage in the six (06) tanks was on average 54 days after hatching. The success of larvi culture is defined by the rate of metamorphosis of the larvae into post-larvae, which, in our case, varied between 0.17% and 3.08%, depending on the production tanks, with an average of 2.8%. These results show that the production of M. vollenhovenii in hatchery is possible, presenting a possibility for aquaculture production of this species as well as for biological control against schistosomiasis in a tropical area

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Availability and Breeding Behaviour of Ganga River Prawn Macrobrachium gangeticum (Bate) and Macrobrachium malcolmsonii (H.M. Edwards)

Asian Fisheries Science ◽

10.33997/j.afs.2006.19.4.005 ◽

2007 ◽

Vol 19 (4) ◽

Author(s):

S. PRASAD ◽

D.R. KANAUJIA

Keyword(s):

Incubation Period ◽

Size Range ◽

Ganga River ◽

Late Night ◽

Breeding Behaviour ◽

Total Length ◽

Controlled Conditions ◽

Macrobrachium Malcolmsonii

Macrobrachium gangeticum and Macrobrachium malcolmsonii prawn species are only available from May to October in the middle stretches of the Ganga river around Patna. The size ranged from 65-215 mm and 60-225 mm total length respectively. The number of M. malcolmsonii was found comparatively much less than that of M. gangeticum. The maximum number of females recorded is in the size range of 95-105 mm and the minimum is 185-205 mm total length in M. malcolmsonii. Maturity is attained at size 75 mm total length and above in both species. The incubation period in M. gangeticum was recorded in 12-14 days and 14 - 17 days in M. malcolmsonii. The color of the eggs in both the species gradually become lighter when the larvae inside the eggs found are fully developed, the color became slight grey. The M. malcolmsonii hatches during the night but M. gangeticum hatches at late night to day. In this paper, efforts have been made to study the availability and breeding behaviour under natural and controlled conditions of both species. It also attempts to study the spawning, incubation and hatching of said species.

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IDENTIFICATION OF VIBRIO BACTERIA CAUSED VIBRIOSIS ON FRESHWATER PRAWN LARVAE (Macrobrachium rosenbergii (de Man))

Jurnal Biologi Udayana ◽

10.24843/jbiounud.2016.v20.i02.p02 ◽

2016 ◽

Vol 20 (2) ◽

pp. 53 ◽

Cited By ~ 1

Author(s):

Ni Wayan Desi Bintari ◽

Retno Kawuri ◽

A. A. Gde Raka Dalem

Keyword(s):

Vibrio Anguillarum ◽

Macrobrachium Rosenbergii ◽

Freshwater Prawn ◽

Limiting Factor ◽

Larval Rearing ◽

Test Results ◽

Bacteriological Study ◽

Larval Production ◽

Ninth Edition ◽

De Man

Freshwater prawn (Macrobrachium rosenbergii (de Man)) farming in Bali needs to be supported by the provisionof healthy prawn larvae. Vibriosis infection can be a limiting factor on larval production system which cause highmass mortality in larvae. Therefore a bacteriological study is very important to identify of Vibrio species whichcan cause vibriosis in freshwater prawn larvae. Screening of Vibrio bacteria carried on larval rearing water atUPT Pembenihan Dinas Kelautan dan Perikanan Provinsi Bali which located in Pesinggahan Village, Klungkung.During study, 5 Vibrio isolates can be characterized (VSP01, VSP02, VSP04, VSP05 and VSP06) which wereisolated as dominant Vibrio bacteria in larval rearing water. Koch postulate test results showed that VSP06 cancause vibriosis in freshwater prawn larvae. The result of identification by BBL Cystal™ Identification Systems andidentification book Bergeys’s Manual of Determinative Bacteriology Ninth Edition (Holt et al., 1994), BL6 wasidentified as Vibrio anguillarum.

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Spatial ecology and growth in early life stages of bay anchovy Anchoa mitchilli in Chesapeake Bay (USA)

Marine Ecology Progress Series ◽

10.3354/meps13431 ◽

2020 ◽

Vol 651 ◽

pp. 125-143

Author(s):

TD Auth ◽

T Arula ◽

ED Houde ◽

RJ Woodland

Keyword(s):

Chesapeake Bay ◽

Spatial Ecology ◽

Environmental Variability ◽

Larval Growth ◽

Larval Abundance ◽

Spatial And Temporal Variability ◽

Estuarine Ecosystem ◽

Anchoa Mitchilli ◽

Larval Production ◽

Bay Anchovy

The bay anchovy Anchoa mitchilli is the most abundant fish in Chesapeake Bay (USA) and is a vital link between plankton and piscivores within the trophic structure of this large estuarine ecosystem. Baywide distributions and abundances of bay anchovy eggs and larvae, and larval growth, were analyzed in a 5 yr program to evaluate temporal and spatial variability based on research surveys in the 1995-1999 spawning seasons. Effects of environmental variability and abundance of zooplankton that serve as prey for larval bay anchovy were analyzed. In the years of these surveys, 97.6% of eggs and 98.8% of larvae occurred in the polyhaline lower bay. Median egg and larval abundances differed more than 10-fold for surveys conducted in the 5 yr and were highest in the lower bay. Within years, median larval abundance (ind. m-2) in the lower bay was generally 1-2 orders of magnitude higher than upper-bay abundance. Salinity, temperature, and dissolved oxygen explained 12% of the spatial and temporal variability in egg abundances and accounted for 27% of the variability in larval abundances. The mean, baywide growth rate for larvae over the 5 yr period was 0.75 ± 0.01 mm d-1, and was best explained by zooplankton concentration and feeding incidence. Among years, mean growth rates ranged from 0.68 (in 1999) to 0.81 (in 1998) mm d-1 and were fastest in the upper bay. We identified environmental factors, especially salinity, that contributed to broadscale variability in egg and larval production.

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Coral husbandry for ocean futures: leveraging abiotic factors to increase survivorship, growth, and resilience in juvenile Montipora capitata

Marine Ecology Progress Series ◽

10.3354/meps13534 ◽

2021 ◽

Vol 657 ◽

pp. 123-133

Author(s):

JR Hancock ◽

AR Barrows ◽

TC Roome ◽

AS Huffmyer ◽

SB Matsuda ◽

...

Keyword(s):

Abiotic Factors ◽

Larval Rearing ◽

Abiotic Conditions ◽

Montipora Capitata ◽

Reef Restoration ◽

Juvenile Corals ◽

Bleaching Response ◽

The Face ◽

Survival And Growth ◽

Global And Local

Reef restoration via direct outplanting of sexually propagated juvenile corals is a key strategy in preserving coral reef ecosystem function in the face of global and local stressors (e.g. ocean warming). To advance our capacity to scale and maximize the efficiency of restoration initiatives, we examined how abiotic conditions (i.e. larval rearing temperature, substrate condition, light intensity, and flow rate) interact to enhance post-settlement survival and growth of sexually propagated juvenile Montipora capitata. Larvae were reared at 3 temperatures (high: 28.9°C, ambient: 27.2°C, low: 24.5°C) for 72 h during larval development, and were subsequently settled on aragonite plugs conditioned in seawater (1 or 10 wk) and raised in different light and flow regimes. These juvenile corals underwent a natural bleaching event in Kāne‘ohe Bay, O‘ahu, Hawai‘i (USA), in summer 2019, allowing us to opportunistically measure bleaching response in addition to survivorship and growth. This study demonstrates how leveraging light and flow can increase the survivorship and growth of juvenile M. capitata. In contrast, larval preconditioning and substrate conditioning had little overall effect on survivorship, growth, or bleaching response. Importantly, there was no optimal combination of abiotic conditions that maximized survival and growth in addition to bleaching tolerances. This study highlights the ability to tailor sexual reproduction for specific restoration goals by addressing knowledge gaps and incorporating practices that could improve resilience in propagated stocks.

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Isolation, morphometry, and culture of Colurella sp. (Rotifera: Ploimida)

AQUATIC SCIENCE & MANAGEMENT ◽

10.35800/jasm.1.2.2013.7276 ◽

2013 ◽

Vol 1 (2) ◽

pp. 143

Author(s):

Petrus P Letsoin ◽

Henneke Pangkey ◽

Julius Sampekalo ◽

Inneke F.M Rumengan ◽

Stenly Wullur ◽

...

Keyword(s):

Body Size ◽

Marine Fish ◽

Fish Larvae ◽

Nannochloropsis Oculata ◽

Tropical Fish ◽

Sampling Location ◽

Larval Rearing ◽

Brachionus Rotundiformis ◽

Marine Fish Larvae ◽

Significant Difference

The rotifer Brachionus rotundiformis (total body length 240.59±10.24 μm, lorica length 175.28±9.18 μm, and lorica width 124.28±7.76μm) is commonly used as starter food in the larval rearing of marine fish. But, larvae of some marine tropical fish species required starter food with body size smaller than B. rotundiformis. The present study was aimed to isolate minute rotifers from nature and to assess the possibility of culturing these rotifers. Sampling of rotifers was conducted in an estuary of Mangket (Kema-Minut), using plankton net (mesh size 40 µm). A trial of culturing the rotifers was conducted at salinities of 10, 20 and 30 ppt by using a microalga, Nannochloropsis oculata. A species of rotifer identified as Colurella sp. (family Lepadellidae) was successfully isolated from the sampling location. Body size of Colurella sp. was extremely small (Total length 123.22±5.45 μm, lorica length 95.96±3.81 μm, and lorica width 53.57±3.11 μm), which were smaller than Brachionus rotundiformis SS-type as a conventional starter food for marine fish larvae. Results of culturing the minute rotifer Colurella sp. showed that the species grew well at salinities of 10, 20 and 30 ppt with no significant difference among treatments (ANOVA, p>0.05), indicating a potential use of minute rotifer Colurellasp. as starter food for marine fish larvae. Rotifera Branchionus rotundiformis (ukuran tubuh: panjang total 240,59±10,24 μm, panjang lorika 175,28±9,18 μm, dan lebar lorika 124,28±7,76μm) sering digunakan sebagai pakan awal pemeliharaan larva ikan laut. Namun, larva beberapa spesis ikan laut tropis membutuhkan pakan awal berukuran tubuh lebih kecil dari Branchionus rotundiformis. Penelitian ini bertujuan untuk mendapatkan minute rotifer dari alam (berukuran tubuh lebih kecil dari B. rotundiformis) dan menguji kemungkinan pemeliharaannya. Sampling rotifer dilakukan di perairan estuari Desa Mangket (Kema-Minut), menggunakan plankton net (ukuran mata jaring 40 µm). Uji coba pemeliharaan dilakukan pada salinitas (10, 20, dan 30 ppt) dengan menggunakan Nannochloropsis oculata. Satu spesies minute rotifer yang teridentifikasi sebagai Colurella sp. (family Lepadellidae) berhasil diisolasi dari lokasi sampling. Colurella sp. memiliki ukuran tubuh sangat kecil (panjang total [PT] 123,22±5,45 µm, panjang lorika [PL] 95,96±3,81 µm, dan lebar lorik [LL] 53,57±3,11 µm) yang mana lebih kecil dari Branchionus rotundiformis tipe-SS sebagai pakan awal larva ikan laut. Hasil uji coba pemeliharaan minute rotifer Colurella sp. menunjukkan bahwa spesis ini dapat tumbuh pada salinitas 10, 20, dan 30 ppt dengan perbedaan kepadatan populasi yang tidak signifikan antar perlakuan (Uji ANOVA, p > 0.05) mengindikasikan potensi pemanfaatan minute rotifer Colurella sp. sebagai pakan awal larva ikan laut.

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Does Larval Rearing Diet Lead to Premating Isolation in Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)?

Insects ◽

10.3390/insects12030203 ◽

2021 ◽

Vol 12 (3) ◽

pp. 203

Author(s):

Xue-Yuan Di ◽

Bin Yan ◽

Cheng-Xu Wu ◽

Xiao-Fei Yu ◽

Jian-Feng Liu ◽

...

Keyword(s):

Mate Choice ◽

Spodoptera Litura ◽

Artificial Diet ◽

Survival Rates ◽

Intrinsic Rate Of Increase ◽

Larval Rearing ◽

Population Parameters ◽

Premating Isolation ◽

Behavioral Isolation ◽

Rate Of Increase

Host plant preference during the larval stage may help shape not only phenotypic plasticity but also behavioral isolation. We assessed the effects of diet on population parameters and mate choice in Spodoptera litura. We raised larvae fed on tobacco, Chinese cabbage, or an artificial diet, and we observed the shortest developmental time and highest fecundity in individuals fed the artificial diet. However, survival rates were higher for larvae on either of the natural diets. Population parameters including intrinsic rate of increase and finite rate of increase were significantly higher with the artificial diet, but this diet led to a lower mean generation time. Copulation duration, copulation time, and number of eggs reared significantly differed between diets. In terms of mate choice, females on the artificial diet rarely mated with males fed on a natural host. Our results support the hypothesis that different diets may promote behavioral isolation, affecting mating outcomes. Thus, findings for populations fed an artificial diet may not reflect findings for populations in the field.

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Spatiotemporal variability in stable isotopes of the Ganga River and factors affecting their distributions

CATENA ◽

10.1016/j.catena.2021.105360 ◽

2021 ◽

Vol 204 ◽

pp. 105360

Author(s):

Shive Prakash Rai ◽

Jacob Noble ◽

Dharmaveer Singh ◽

Yadhvir Singh Rawat ◽

Bhishm Kumar

Keyword(s):

Stable Isotopes ◽

Ganga River ◽

Spatiotemporal Variability ◽

Factors Affecting

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Improvement of water quality for mass anopheline rearing: evaluation of the impact of ammonia-capturing zeolite on larval development and adult phenotypic quality

Parasites & Vectors ◽

10.1186/s13071-021-04763-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Nwamaka Oluchukwu Akpodiete ◽

Frédéric Tripet

Keyword(s):

Water Quality ◽

Larval Development ◽

Larval Density ◽

Malaria Vector Control ◽

Larval Rearing ◽

Emergence Success ◽

Phenotypic Quality ◽

Rearing Density ◽

Daily Water ◽

The Impact

Abstract Background Malaria vector control approaches that rely on mosquito releases such as the sterile insect technique (SIT) and suppression or replacement strategies relying on genetically modified mosquitoes (GMM) depend on effective mass production of Anopheles mosquitoes. Anophelines typically require relatively clean larval rearing water, and water management techniques that minimise toxic ammonia are key to achieving optimal rearing conditions in small and large rearing facilities. Zeolites are extensively used in closed-system fish aquaculture to improve water quality and reduce water consumption, thanks to their selective adsorption of ammonia and toxic heavy metals. The many advantages of zeolites include low cost, abundance in many parts of the world and environmental friendliness. However, so far, their potential benefit for mosquito rearing has not been evaluated. Methods This study evaluated the independent effects of zeolite and daily water changes (to simulate a continuous flow system) on the rearing of An. coluzzii under two feed regimes (powder and slurry feed) and larval densities (200 and 400 larvae per tray). The duration of larval development, adult emergence success and phenotypic quality (body size) were recorded to assess the impact of water treatments on mosquito numbers, phenotypic quality and identification of optimal feeding regimes and larval density for the use of zeolite. Results Overall, mosquito emergence, duration of development and adult phenotypic quality were significantly better in treatments with daily water changes. In treatments without daily water changes, zeolite significantly improved water quality at the lower larval rearing density, resulting in higher mosquito emergence and shorter development time. At the lower larval rearing density, the adult phenotypic quality did not significantly differ between zeolite treatment without water changes and those with daily changes. Conclusions These results suggest that treating rearing water with zeolite can improve mosquito production in smaller facilities. Zeolite could also offer cost-effective and environmentally friendly solutions for water recycling management systems in larger production facilities. Further studies are needed to optimise and assess the costs and benefits of such applications to Anopheles gambiae (s.l.) mosquito-rearing programmes. Graphic abstract

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Active prey selection in developing larvae of Atlantic bluefin tuna (Thunnus thynnus) in spawning grounds of the Gulf of Mexico

Journal of Plankton Research ◽

10.1093/plankt/fbab020 ◽

2021 ◽

Author(s):

Akihiro Shiroza ◽

Estrella Malca ◽

John T Lamkin ◽

Trika Gerard ◽

Michael R Landry ◽

...

Keyword(s):

Gulf Of Mexico ◽

Prey Selection ◽

Bluefin Tuna ◽

Gut Contents ◽

Physical Factors ◽

Larval Rearing ◽

Thunnus Thynnus ◽

Small Copepod ◽

Atlantic Bluefin Tuna ◽

Larval Stages

Abstract Bluefin tuna spawn in restricted areas of subtropical oligotrophic seas. Here, we investigate the zooplankton prey and feeding selectivity of early larval stages of Atlantic bluefin tuna (ABT, Thunnus thynnus) in larval rearing habitat of the Gulf of Mexico. Larvae and zooplankton were collected during two multi-day Lagrangian experiments during peak spawning in May 2017 and 2018. Larvae were categorized by flexion stage and standard length. We identified, enumerated and sized zooplankton from larval gut contents and in the ambient community. Ciliates were quantitatively important (up to 9%) in carbon-based diets of early larvae. As larvae grew, diet composition and prey selection shifted from small copepod nauplii and calanoid copepodites to larger podonid cladocerans, which accounted for up to 70% of ingested carbon. Even when cladoceran abundances were <0.2 m−3, they comprised 23% of postflexion stage diet. Feeding behaviors of larvae at different development stages were more specialized, and prey selection narrowed to appendicularians and primarily cladocerans when these taxa were more abundant. Our findings suggest that ABT larvae have the capacity to switch from passive selection, regulated by physical factors, to active selection of presumably energetically optimal prey.

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