83602 research outputs found
Sort by
The effect of dietary docosahexaenoic acid (DHA; 22:6n-3) on photoreceptor abundance, rhodopsin expression and growth in developing gilthead sea bream (<em>Sparus aurata</em>) larvae
Get PDFThis study determined the effect of prey DHA on larval gilthead sea bream (GSB; Sparus aurata) photoreceptor abundance, rhodopsin expression, and growth performance. It was carried out in a twenty-eight 400 l conical tank system that was stocked with 100 viable GSB eggs/l/tank. This allowed the testing of 4 levels of rotifer DHA; 0.99 (Low; L), 1.9 (Intermediate low; I-L), 3.2 (Intermediate high; I-H) and 12.1(High; H) mg DHA/g DW rotifer, which were fed (10 rotifers/ml) to 3-16 DPH larvae. These rotifer diets continued to be offered to 17-34 DPH fish, although these larvae predominantly fed on 4 DHA enriched Artemia nauplii treatments that were offered at a concentration from 0.1 nauplii/ml to 4 nauplii/ml, depending on larval age. This resulted in 4 DHA rotifer-Artemia ranges: 0.99-0.0 (L), 1.9-2.6 (I-L), 3.2-7.2 (I-H), and 12.1-11.77 (H) mg DHA/g DW. The 4 DHA treatments and ranges were tested in replicates of 7 conical tanks per treatment. Increasing rotifer DHA significantly (P<0.0001) improved TL, in an exponential manner, throughout larval rearing. DW in 34 DPH larvae was markedly (P<0.05) enhanced with dietary DHA inclusion in the rotifers and Artemia. There was a significant (P < 0.005) prey DHA dose dependent range effect on the abundance of photoreceptor cells in the retina of 34 DPH larvae. The gene expression of rhodopsin in GSB larvae was significantly (P<0.05) upregulated with dietary DHA dose range and larval age (P<0.0001). This study established a link between dietary DHA level with photoreceptor abundance and rhodopsin expression, which led to improved vision, prey acquisition, and growth in developing GSB larvae
Expression of Hsp70 in the red swamp crayfish, <em>Procambarus clarkii</em> in response to immune challenge
Get PDFA heat shock protein 70 (Hsp70) was identified from *Procambarus clarkii* (named as PcHsp70). The open reading frame of the PcHsp70 cDNA was 1917 bp, encoding a 638 aa protein with signature sequences of the Hsp70 family. Tissue distribution results showed that PcHsp70 has relatively high expression in immune-related tissues such as hepatopancreas, gill, and hemocytes. The expressions of PcHsp70 in hepatopancreas and gill were significantly induced by Gram-positive bacterium, Gram-negative bacterium, and white spot syndrome virus stimulation, indicating that PcHsp70 may be involved in the immune response to pathogen invasion. The research will provide a foundation for understanding the resistance and stress mechanism of Hsp70 in *P. clarkii*
Antiparasitic activity of medicinal plants against protozoan fish parasite <em>Ichthyophthirius multifiliis</em>
Get PDFThe parasitic ciliate Ichthyophthirius multifiliis infests all freshwater fish species and can cause severe economic losses in aquaculture. The present study aims to evaluate the antiparasitic activity of onion (Allium cepa), sage (Salvia officinalis), menthe (Menthe spicata), garlic (Allium sativum), lavender (Lavandula officinalis) and oregano (Origanum onites) essential oils against I. multifiliis trophonts. Gas Chromatography-Mass Spectrometry (GC-MS) analyses determined these essential oils' chemical components. The major components were dipropyl disulfide (46.15%) in onion, alpha-thujone (46.80%) in sage, carvone (48.00%) in menthe, diallyl disulfide (32.70%) in garlic, 1,8-cineole (32.65%) in lavender; carvacrol (73.00%) in oregano. I. multifilis trophonts were isolated from infected European catfish's skin and gill arches (Silurus glanis). Then in vitro, antiparasitic assays obtained those essential oils of sage (0.50 mL L^-1^), lavender (0.25-, and 0.50-mL L^-1^), and oregano (0.1, 0.25- and 0.50-mL L^-1^) have been found as 100% effective against trophonts at the different concentration of after 60 min of exposure, respectively (pI. multifiliis trophonts
Growth performance of Mediterranean Sea species under high temperatures
Get PDFDiversifying aquaculture in Saudi Arabia with the inclusion of finfish species already reared in the Mediterranean Sea requires a sufficient understanding of the preferences and limits of cultured fish under local conditions. This study was conducted using three finfish species, juveniles (135–155g), meager (Argyrosomus regius), European seabass (Dicentrarchus labrax), and greater amberjack (Seriola dumerili), to assess their growth performance under high temperatures for three-month-long thermal trials. Each species trial was performed in triplicates in a recirculating aquaculture system, while three temperature ranges, 24°C–25°C, 28°C–29°C, and 33°C–34°C, were tested, representing the average temperatures in the Mediterranean and Red Seas. Both meager and European seabass performed similarly between the first two temperatures, indicating that the optimum range lies within that thermal window. Growth performance indicates that it is lower for meager than it is for European seabass. The greater amberjack’s growth performance was similar for the first two temperatures. The temperature of tolerance was 33°C for all species. The species appeared to have similar thermal tolerance with notable differences in the preferable temperature for optimum performance. The findings of this study can be used to improve the growth performance and feed efficiency of Mediterranean species farming in temperature ranges ranging from 24°C–28°C
The Kaselehlie Press
No full textVolume 23Digital issues of the Kaselehlie Press are made available here in open access with permission of publisher Bill Jaynes, who holds copyright. Any reuse besides that which is allowed under fair-use laws is subject to copyright. Current issues of the paper are freely available online via issue.com/kpressfsm. Hard copy back issues (through volume 21) are available at the University of Hawaii-Manoa Library -- location information can be found in the paper's cataloging record
Book Reviews
No full textBook Reviews: Fierce and Fearless: Patsy Takemoto Mink, First Woman of Color in Congress by Judy Tsu-Chun Wu and Gwendolyn Mink; The Education of Betsey Stockton: An Odyssey of Slavery and Freedom by Gregory Nobles; Leveraging Sovereignty: Kauikeaouli’s Global Strategy for the Hawaiian Nation, 1825–1854 by J. Susan Corley; Pacific Confluence: Fighting Over the Nation in Nineteenth-Century Hawaiʻi by Christen T. Sasaki; Cooling the Tropics: Ice, Indigeneity, and Hawaiian Refreshment by Hiʻilei Julia Kawehipuaakahaopulani Hobar