Microhabitat selectivity shapes the seascape ecology of a carnivorous macroalgae-associated tropical fish

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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Importance of Zebrafish as an efficient research model for the screening of novel therapeutics in neurological disorders

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527319666201207211927 ◽

2020 ◽

Vol 19 ◽

Author(s):

Diksha Saluja ◽

Rishabh Jhanji ◽

Swati Kaushal ◽

Bharti Verma ◽

Neelam Sharma ◽

...

Keyword(s):

Animal Model ◽

Neurological Disorders ◽

Tropical Fish ◽

Mammalian Brain ◽

Behavioral Repertoire ◽

Experimental Procedure ◽

Novel Drugs ◽

Associated Functions ◽

Pharmacology And Toxicology ◽

Rats And Mice

Abstract:: In the previous years of research, the use of animal model becomes very common for the screening of novel drugs. Animal model represents the complex problems of humans into simplest forms which can be extended further to include the experimental procedure. The most successful models in neuroscience, rats and mice, undoubtedly considered as one of the best models to understand the psychology of mammalian brain and its associated functions involved in various behavioral repertoire. Moreover, recently researchers in behavioral neuroscience are focusing more on the use of aquatic animals especially fish as model species due to their simplicity, and cost effectiveness. Zebrafish (Danio rerio) is a tropical fish from minnow family a genetic structure surprisingly 84 % similar to humans. It is gaining popularity as a model to study the mechanism in behavioral neuropharmacology. Moreover, Zebrafish is having numerous advantages over other rodent models like ease in maintenance due to their small size; breeding power is more, transparency of embryos, overall reduced cost of experimentation and many more. Nowadays, it is considered as an ideal model to study the neurobehavioral aspects with relevance to humans. It is also used in varieties of scientific studies like genetics, neuroscience, pharmacology, and toxicology. In this manuscript, we have described the feasibility and importance of Zebrafish as a model for the screening of novel drugs for different neurological disorders.

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Predicting range-shift success potential for tropical marine fishes using external morphology

Biology Letters ◽

10.1098/rsbl.2016.0505 ◽

2016 ◽

Vol 12 (9) ◽

pp. 20160505 ◽

Cited By ~ 9

Author(s):

Shannen M. Smith ◽

Rebecca J. Fox ◽

Jennifer M. Donelson ◽

Megan L. Head ◽

David J. Booth

Keyword(s):

Fish Larvae ◽

Climatic Conditions ◽

Invasion Success ◽

Range Shift ◽

Tropical Fish ◽

Range Shifts ◽

Native Community ◽

The Family ◽

Moorish Idol ◽

New Habitats

With global change accelerating the rate of species' range shifts, predicting which are most likely to establish viable populations in their new habitats is key to understanding how biological systems will respond. Annually, in Australia, tropical fish larvae from the Great Barrier Reef (GBR) are transported south via the East Australian Current (EAC), settling into temperate coastal habitats for the summer period, before experiencing near-100% mortality in winter. However, within 10 years, predicted winter ocean temperatures for the southeast coast of Australia will remain high enough for more of these so-called ‘tropical vagrants’ to survive over winter. We used a method of morphological niche analysis, previously shown to be an effective predictor of invasion success by fishes, to project which vagrants have the greatest likelihood of undergoing successful range shifts under these new climatic conditions. We find that species from the family of butterflyfishes (Chaetodontidae), and the moorish idol, Zanclus cornutus , are most likely to be able to exploit new niches within the ecosystem once physiological barriers to overwintering by tropical vagrant species are removed. Overall, the position of vagrants within the morphospace was strongly skewed, suggesting that impending competitive pressures may impact disproportionately on particular parts of the native community.

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