|   | 
Details
   web
Records
Author Bapary, Mohammad AJ; Amin, Md Nurul; Takeuchi, Yuki; Takemura, Akihiro
Title The stimulatory effects of long wavelengths of light on the ovarian development in the tropical damselfish, Chrysiptera cyanea Type Journal Article
Year 2011 Publication (up) Aquaculture Abbreviated Journal
Volume 314 Issue 1-4 Pages 188-192
Keywords animals; fish; reproduction
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ schroer @ Serial 1575
Permanent link to this record
 

 
Author Camus, Thomas; Zeng, Chaoshu
Title Effects of photoperiod on egg production and hatching success, naupliar and copepodite development, adult sex ratio and life expectancy of the tropical calanoid copepod Acartia sinjiensis Type Journal Article
Year 2008 Publication (up) Aquaculture Abbreviated Journal
Volume 280 Issue 1-4 Pages 220-226
Keywords animals; Acartia sinjiensis; Egg production and hatching success; Life expectancy; Naupliar and copepodite development; Photoperiod; Sex ratio
Abstract The tropical calanoid copepod Acartia sinjiensis has good potential for mass culture as live feed for reef fish larvae. The present study was conducted to evaluate the effects of photoperiod on various parameters related to A. sinjiensis productivity in culture. Five photoperiods of Light:Dark = 0:24; 6:18; 12:12; 18:6 and 24:0h were setup. Daily egg production of individual females under each photoperiod was monitored for 8 consecutive days. The females were randomly selected daily from stock cultures kept under respective photoperiods and discarded after experiment. The results showed a clear trend of increasing egg production with longer illumination period. Under constant darkness, acclimatization was evident as egg output increased steadily over the 8??day period. Statistics showed that photoperiod significantly (p < 0.005) affected mean daily egg production, with the highest egg output recorded at 18L:6D and 24L:0D (17.6 ?? 1.7 and 17.6 ?? 1.8 eggs/female/day respectively), which were significantly higher than all other treatments. Photoperiod also significantly affected 48??h egg hatching success (p < 0.005), a trend of increased hatching success with longer light phase was demonstrated. The highest hatching rate (87.2 ?? 1.4%) was recorded at 24L:0D, which was significantly higher than the 0L:24D and 6L:18D treatments but not significantly different from the second highest (85.3 ?? 2.6%) hatching rate of 18L:6D treatment. Photoperiod was further confirmed to significantly (p < 0.005) affected naupliar and copepodite development with accelerated development observed with increased illumination period of photoperiods. Mean development time from egg to adult was the shortest at 6.00 ?? 0.33 days under constant light (24L:0D), followed by 6.24 ?? 0.24??days at 18L:6D, both were significantly shorter than that of 0L:24D and 6L:18D treatments although no significantly difference was detected between themselves. Adult life expectancy was also found significantly (p < 0.005) affected by photoperiod with the shortest adult life span recorded under constant light (24L:0D) (9.4 ?? 0.4??days), which was significantly shorter than all other photoperiods tested. Adult sex ratio was the only parameter tested that was not significantly affected by photoperiod, a skewed sex ratio in favor of female was found across all photoperiod treatments. Based on results of current study, it is recommended that a photoperiod of 18L:6D being adopted for A. sinjiensis culture to maximize its productivity for aquaculture hatcheries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ schroer @ Serial 1581
Permanent link to this record
 

 
Author Fukuda, H.; Torisawa, S.; Sawada, Y.; Takagi, T.
Title Developmental changes in behavioral and retinomotor responses of Pacific bluefin tuna on exposure to sudden changes in illumination Type Journal Article
Year 2010 Publication (up) Aquaculture Abbreviated Journal
Volume 305 Issue 1-4 Pages 73-78
Keywords animals; fish; animal behavior
Abstract Schooling behavior traits during the process of retinomotor response from scotopic to photopic vision were examined in cultivated juvenile Pacific bluefin tuna (PBT) at 3 different ages. After a sudden change in illumination from darkness to 300 lx, retinal adaptations changed from scotopic to photopic vision. Retinomotor and schooling indices showed strong agreement, with juvenile PBTs forming polarized schools upon complete retinal adaptation to photopic vision. The behavioral and retinal adaptation to sudden illumination took 20, 15, and 10 min after illumination in PBT 25, 40, and 55 days after hatching (dah). At 40 dah, PBT took a longer time to adapt than fish aged 55 dah and showed the highest swimming speed, including momentary bursts of swimming immediately after illumination. This suggested that these fish were swimming at high speed under poor visibility conditions. In contrast, PBT at 55 dah showed a gradual increase in swimming speed that correlated with their retinal adaptation. Therefore, behavioral and retinal adaptation traits changed during growth, suggesting that the high mortality in PBT around 40 dah, due to collisions with the tank and net walls at dawn, may be because these adapt more slowly than fish at 55 dah and were swimming at a relatively high speed under conditions of poor visibility.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ schroer @ Serial 1589
Permanent link to this record
 

 
Author Vera, L. M.; Migaud, H.
Title Continuous high light intensity can induce retinal degeneration in Atlantic salmon, Atlantic cod and European sea bass Type Journal Article
Year 2009 Publication (up) Aquaculture Abbreviated Journal
Volume 296 Issue 1-2 Pages 150-158
Keywords animals; fish; vision
Abstract Retinal photodamage has previously been studied in teleost fish but very few have been performed on aquaculture species. To study retinal damage, Atlantic cod (Gadus morhua), Atlantic salmon (Salmo salar) and European sea bass (Dicentrarchus labrax) were previously acclimated to a control 12L:12D photoperiod with standard experimental low light intensity (0.1 W/m2, equivalent to 3.2 × 1013 photons/s/cm2) for at least 4 weeks and then kept under constant darkness (DD) for 3 days. Thereafter, fish were exposed to continuous high intensity light (51–380 W/m2, equivalent to 1.63 × 1016–1.22 × 1017 photons/s/cm2) for 3, 7, 15 or 25 days before returning to a control 12L:12D photoperiod (same intensity than during acclimation period) to study retinal regeneration over a period of 30 days. Retinal damage was exclusively assessed through the analysis of morphometric parameters. Results showed the presence of light-induced damage in the three species examined, as well as recovery once the control photocycle was restored. Cod was the most light-sensitive species as demonstrated by early signs of retinal damage (from three days of exposure) and reduced photoreceptor layer thickness (PRos/is) (43.1% relative to basal value in comparison to 51.6% and 73.3% respectively in salmon and sea bass). However, once the light–dark cycle was resumed the retina recovered in the three species studied (after 15 days in cod and 30 days in salmon and sea bass). Exposure to continuous high intensity light also resulted in significantly increased plasma cortisol levels in cod at LL15 (13.4 ± 2.0 ng/ml) and sea bass at LL3 (120.6 ± 12.2 ng/ml) and LD15 (54.2 ± 7.1 ng/ml). These results have important welfare implications with regards to the use of artificial light in culture and should be considered when designing lighting protocols in the aquaculture industry.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ schroer @ Serial 1605
Permanent link to this record
 

 
Author Konkal, P.; Ganesh, C.B.
Title Exposure to low or high light intensity affects pituitary-testicular activity in the fish Oreochromis mossambicus Type Journal Article
Year 2018 Publication (up) Aquaculture Abbreviated Journal Aquaculture
Volume 497 Issue Pages 109-116
Keywords Animals
Abstract Light is an important factor for the successful reproduction of most fish. In this investigation, effect of different light intensities on pituitary-testis axis was studied for a period of 21 days, under normal photoperiodic regime in the tilapia Oreochromis mossambicus. The mean numbers of spermatogonia (Sg), primary spermatocytes (Ps), secondary spermatocytes (Ss), early spermatids (Est) and late spermatids (Lst) did not show significant difference between fish exposed to moderate light intensity (MLI) and initial controls or controls, whereas the mean numbers of Sg were significantly lower in fish exposed to low light intensity (LLI) compared to those of initial controls, controls and MLI groups. However, the mean numbers of Ps, Ss, Est and Lst were significantly lower in fish exposed to LLI and high light intensity (HLI) compared to those of other experimental groups. Furthermore, in the pituitary gland, weakly immunoreactive luteinizing hormone (LH) secreting cells were observed in the proximal pars distalis (PPD) region in fish exposed to LLI and HLI in contrast to the intense immunolabelling of these cells in initial controls, controls and MLI groups. The androgen receptors showed diminished immunoreactivity in the Sertoli cells along the seminiferous lobules of the testis in fish exposed to LLI and HLI, whereas the strongly immunoreactive androgen receptors were observed in the Sertoli cells in initial controls, controls and MLI groups. Taken together, these results indicate that long-term exposure to low or high light intensity light suppresses spermatogenetic process and that this inhibition is due to reduced secretory activity of LH cells in the pituitary gland and androgen secretion in the testis of the fish O. mossambicus.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0044-8486 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1974
Permanent link to this record