Scotian Halibut Ltd

Woods, Canada

Scotian Halibut Ltd

Woods, Canada
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Corey P.,Scotian Halibut Ltd | Kim J.K.,University of Connecticut | Kim J.K.,Dalhousie University | Duston J.,Dalhousie University | Garbary D.J.,St. Francis Xavier University
Algae | Year: 2014

Palmaria palmata was integrated with Atlantic halibut Hippoglossus hippoglossus on a commercial farm for one year starting in November, with a temperature range of 0.4 to 19.1°C. The seaweed was grown in nine plastic mesh cages (each 1.25 m3 volume) suspended in a concrete sump tank (46 m3) in each of three recirculating systems. Two tanks received effluent water from tanks stocked with halibut, and the third received ambient seawater serving as a control. Thalli were tumbled by continuous aeration, and held under a constant photoperiod of 16: 8 (L: D). Palmaria stocking density was 2.95 kg m-3 initially, increasing to 9.85 kg m-3 after a year. Specific growth rate was highest from April to June (8.0 to 9.0°C), 1.1% d-1 in the halibut effluent and 0.8% d-1 in the control, but declined to zero or less than zero above 14°C. Total tissue nitrogen of Palmaria in effluent water was 4.2 to 4.4% DW from January to October, whereas tissue N in the control system declined to 3.0-3.6% DW from April to October. Tissue carbon was independent of seawater source at 39.9% DW. Estimated tank space required by Palmaria for 50% removal of the nitrogen excreted by 100 t of halibut during winter is about 29,000 to 38,000 m2, ten times the area required for halibut culture. Fifty percent removal of carbon from the same system requires 7,200 to 9,800 m2 cultivation area. Integration of P. palmata with Atlantic halibut is feasible below 10°C, but is impractical during summer months due to disintegration of thalli associated with reproductive maturation. © 2014 The Korean Society of Phycology.

Corey P.,Dalhousie University | Corey P.,Scotian Halibut Ltd. | Kim J.K.,University of Connecticut | Garbary D.J.,St. Francis Xavier University | And 2 more authors.
Journal of Applied Phycology | Year: 2012

To evaluate the nutrient removal capabilities of two red macroalgae, apical blades were cultured in the lab for 4 weeks at either 6, 10, or 17°C and nitrate at either 30 or 300 μM, typical of the seasonal range of conditions at a land-based Atlantic halibut farm. Stocking density was 2.0 g L -1, irradiance 125 μmol photons m -2 s -1, photoperiod 16:8 (L:D), and nitrogen to phosphorus ratio 10:1. For both species, the highest growth rate was at 300 μM NO 3 - with Palmaria palmata growing fastest at 6°C, 5.8% day -1, and Chondrus crispus growing best at 17°C, 5.5% day -1. Nitrogen and carbon removal by P. palmata was inversely related to temperature, the highest rate at 6°C and 300 μM NO 3 - of 0.47 mg N and 6. 3 mg C per gram dry weight per day. In contrast, C. crispus removal of N was independent of temperature, with mean removal of 0.49 mgN gDW -1 day -1 at 300 μM NO 3 -. The highest carbon removal by C. crispus was 4.4 mgC gDW -1 day -1 at 10°C and 300 μM nitrate, though not significantly different from either 6 or 17°C and 300 μM nitrate. Tissue carbon:nitrogen ratios were >20 in both species at 30 μM nitrate, and all temperatures indicating nitrogen limitation in these treatments. Phycoerythrin content of P. palmata was independent of temperature, with means of 23.6 mg gFW -1 at 300 μM nitrate. In C. crispus, phycoerythrin was different only between 6°C and 17°C at 300 μM nitrate, with the highest phycoerythrin content of 12.6 mg gFW -1 at 17°C. Morphological changes were observed in P. palmata at high NO 3 - concentration as curling of the fronds, whilst C. crispus exhibited the formation of bladelets as an effect of high temperature. © 2011 Springer Science+Business Media B.V.

Corey P.,Scotian Halibut Ltd | Kim J.K.,University of Connecticut | Duston J.,Dalhousie University | Garbary D.J.,St. Francis Xavier University | Prithiviraj B.,Dalhousie University
Journal of Applied Phycology | Year: 2013

Palmaria palmata and Chondrus crispus were grown for 4 weeks in 1-L flasks at 10 °C to evaluate nutrient uptake and their potential application as nutrient biofilters in effluent from finfish culture. For greatest bioremediation benefit within an integrated system, we conclude that a seaweed biofilter using these species should be placed prior to bacterial biofiltration for exposure to greater proportions of ammonium than nitrate, though it is apparent that the productivity of both species is not influenced by the nitrogen source. Five combinations of ammonium- and nitrate-nitrogen were compared, each with a total N concentration of 300 μM (300:0, 270:30, 150:150, 30:270, 0:300). Molar nitrogen/phosphorus ratio was 10:1. The maximum growth rates were 8.9 and 6.0 % per day for P. palmata and C. crispus, respectively. For both species, the total nitrogen uptake was highest at 300 μM ammonium, 4.46 mgN gDW-1 day-1 for P. palmata and 3.40 mg N g DW-1 day-1 for C. crispus. Over a 24-h period, 23-37 % of the available nitrate and 91-100 % of the available ammonium were taken up by P. palmata. In the same period, C. crispus took up 55-87 % of available nitrate and 89-100 % of ammonium. Tissue N in P. palmata was highest (4.1 %) at 270 and 300 μM ammonium, while the nitrogen source did not have a significant effect on the tissue N of C. crispus (mean of 4.6 %). © 2013 Springer Science+Business Media Dordrecht.

Ding F.,Chinese Academy of Fishery Sciences | Milley J.E.,National Research Council Canada | Rommens M.,Scotian Halibut Ltd | Li J.,CAS Qingdao Institute of Oceanology | And 2 more authors.
Cryobiology | Year: 2012

Hormone implantation is widely applied in halibut (Hippoglossus hippoglossus L.) aquaculture to extend the sperm production season of broodstock males. The ability to combine this technique with cryopreservation would increase sperm availability, thereby improving reproduction success and facilitating gene management. In this paper, the cryopreservation ability of sperm from hormone-treated males was examined at three times post-implantation and compared with that of sperm from males that were not hormone-treated. All sperm samples were cryopreserved using the same method. The effectiveness of these techniques was assessed by examining the fertilization rate and motility of thawed sperm. The spermotocrit and concentration of fresh sperm samples were measured to reveal the effect of hormone implantation on sperm characteristics. The reported results indicate that hormone implantation did not affect cryopreservation efficiency. The fertilization rate resulting from thawed sperm of hormone-treated males showed no significant difference from that of untreated males or from fresh sperm. A significant positive relationship was demonstrated between the spermatocrit and concentration of sperm; and a significant decrease of spermatocrit was found in sperm collected from hormone-treated males 14. days post-implantation. No significant linear relationship between spermotocrit and fertilization rate of thawed sperm was shown. © 2012.

Ding F.,Chinese Academy of Fishery Sciences | Lall S.P.,National Research Council Canada | Li J.,CAS Qingdao Institute of Oceanology | Lei J.,Chinese Academy of Fishery Sciences | And 2 more authors.
Cryobiology | Year: 2011

Development of Atlantic halibut (Hippoglossus hippoglossus) aquaculture will be enhanced with cryopreservation of halibut sperm by ensuring a reliable supply of sperm of desired quality and quantity. To assist in its commercial application, the cryopreservation of large volumes of halibut sperm was investigated. Three cryoprotectants were compared: dimethyl sulfoxide (DMSO), polyethylene glycol (PG) and glycerol (GLY) at two concentrations (10% or 15%). Two salt solutions, Hanks' balanced salt solution (HBSS) and 0.1M KHCO3 with 0.125M sucrose solution (KS) were tested as diluents. Both factors were examined in 1.6mL volumes. A cryopreservation volume of 4mL and a low dilution ratio (1:1) were examined separately. Based on motility and fertilization rate, 10% and 15% DMSO diluted with HBSS or KS solution proved to be effective extenders with mean fertilization rates ranging from 52.2±27.2% to 65.8±26.1%; none of which were significantly different from that of the control. Four other extenders, 10% PG or 10% GLY with HBSS or KS, resulted in significantly lower fertilization rates. Use of a 4mL cryopreservation volume did not exhibit a significant effect on fertilization rate or motility of post-thawed sperm compared to a 1.6mL volume (P>0.05); while the use of a dilution ratio of one part sperm with three parts cryopreservation solution (1:3 v/v with sperm concentration of 0.51±0.11×1010cells/ml) had a significantly better preservation effect than using a ratio of 1:1 with sperm concentration of 1.02±0.21×1010cells/ml (P<0.05). From these results, an optimized protocol for the cryopreservation of Atlantic halibut sperm using a volume as large as 4mL has been established. © 2011 Elsevier Inc.

Murray H.M.,Institute for Marine Biosciences | Murray H.M.,Scotian Halibut Ltd. | Lall S.P.,Institute for Marine Biosciences | Rajaselvam R.,Genome Atlantic | And 8 more authors.
Marine Biotechnology | Year: 2010

An experimental microdiet prepared using an internal gelation method was used to partially replace the traditional live feed (Artemia) for larval Atlantic halibut, Hippoglossus hippoglossus L. Three trials were conducted with microdiet introduced at 20, 32, and 43 days post first feeding and larvae were sampled at approximately 2, 13, 23, and 33 days after microdiet introduction in each trial. The success of feeding was assessed by morphometrics and histological analysis of gut contents. Microdiet particles were readily consumed after a period of adaptation and provided an adequate source of nutrients with no significant increase in mortality in the microdiet-fed group compared to the control group. However, growth was limited and there was an increased incidence of malpigmentation of the eye and skin. Subtle changes in underlying digestive and developmental physiology were revealed by microarray analysis of RNA from control and experimental fish given microdiet from day 20 post first feeding. Fifty-eight genes were differentially expressed over the four sampling times in the course of the trial and the 28 genes with annotated functions fell into five major categories: metabolism and biosynthesis, cell division and proliferation, protein trafficking, cell structure, and stress. Interestingly, several of these genes were involved in pigmentation and eye development, in agreement with the phenotypic abnormalities seen in the larvae. © 2009 Her Majesty the Queen in Right of Canada, as represented by the National Research Council of Canada.

Murray H.M.,National Research Council Canada | Lall S.P.,National Research Council Canada | Rajaselvam R.,Genome Atlantic | Boutilier L.A.,Genome Atlantic | And 6 more authors.
Aquaculture | Year: 2010

Aquaculture feeds for carnivorous finfish species have been dependent upon the use of fish meal as the major source of dietary protein; however, the increasing demands upon the finite quantity of this high-quality protein source requires that feeds become increasingly comprised of alternative plant and/or animal protein. Soybean meal has been has been used to partially replace fish meal in the diets of several fish but it is known to cause enteritis in Atlantic salmon, Salmo salar. We have compared two groups of juvenile (207.2 ± 6.6 g) Atlantic halibut, Hippoglossus hippoglossus, L., fed diets containing fish meal (FM; control) or 30% soybean meal (SBM; experimental) as a protein source for 3 weeks. No detectable difference in feed intake or palatability was evident with the SBM diet relative to the FM diet. Histological examination of the distal intestine was performed to examine leukocyte infiltration of the lamina propria and other changes in morphology commonly observed with soybean-induced enteritis of salmonids. No significant difference was found between fish fed the FM and SBM diets. Global gene expression profiling performed using a high-density oligonucleotide microarray containing 9260 unique features, printed in quadruplicate, from Atlantic halibut revealed subtle underlying changes in the expression of several immune genes and genes involved in muscle formation, lipid transport, xenobiotic detoxification, digestion and intermediary metabolism. These results indicate that SBM can be used successfully as a replacement for animal protein in diet for juvenile Atlantic halibut, although long-term effects on the immune system may ensue. Crown Copyright © 2009.

Kim J.K.,Dalhousie University | Duston J.,Dalhousie University | Corey P.,Dalhousie University | Corey P.,Scotian Halibut Ltd. | Garbary D.J.,St. Francis Xavier University
Aquaculture | Year: 2013

Optimal stocking density of the marine red algae Chondrus crispus and Palmaria palmata was determined to maximize productivity and nitrogen removal in a land-based Atlantic halibut farm. Both species were cultured at 0.2, 2, 4, 6 and 10kgm-2 for four weeks at 140±10μmolphotonsm-2s-1 of photosynthetically active radiation (PAR) and 16:8 L:D photoperiod. For each species, two rearing temperatures were compared at different times of the year: 6 (Dec.) and 13°C (June) for C. crispus, and 6 (Mar.) and 16°C (July) for P. palmata. Growth rates of both species were inversely dependent on stocking density at all temperatures; however, the productivity (gfresh weightd-1) in Chondrus was significantly higher at 2kgm-2 than 0.2kgm-2 at both temperatures. By contrast, productivity of Palmaria was independent of stocking densities of 0.2 through 6.0kgm-2 at both temperatures. The net N removal in Chondrus was the highest at 2.0kgm-2 at both temperature conditions. Palmaria also showed the highest N removal at 2.0kgm-2 at 6°C but at 4.0kgm-2 at 16°C. Overall, C. crispus was the better performer year-round than P. palmata in terms of productivity and nutrient removal capacity. © 2013 Elsevier B.V.

Caines S.,Dalhousie University | Manriquez-Hernandez J.A.,Dalhousie University | Duston J.,Dalhousie University | Corey P.,Scotian Halibut Ltd | Garbary D.J.,St. Francis Xavier University
Journal of Applied Phycology | Year: 2014

The high cost of aeration needed to tumble culture macroalgae is a limiting factor for integration with land-based finfish culture. Toward reducing this electricity cost, we compared intermittent aeration (16 h on:8 h off) with continuous aeration (24 h on) on the productivity of two strains of Chondrus crispus (Basin Head and Charlesville) and Palmaria palmata from Atlantic Canada between May and June 2011. Algal fronds were cultured under a 16:8-h light/dark photoperiod in 50-L tanks supplied with finfish effluent (49 μmol L−1 of ammonium and 11μmol L−1 of phosphate) at a mean water flow rate of 0.4 L min−1. Nitrogen (N) influx was 1.8 gN m−2 day−1, and phosphorus (P) influx was 0.9 gP m−2 day−1, with uptake rates ranging from 0.02 to 2.4 gN m−2 day−1 and −0.2 to 0.4 gP m−2day−1. On average, the macroalgae culture system (algae and biofilms) removed 1.0gNm−2day−1 (51.9%). The growth of macroalgae (pooled across treatment and strain) ranged from 0.5 to 1.6%day−1, which accounted for a yield of 2.2 to 5.4 g DW m−2 day−1. Switching off aeration at night improved the growth rate of Basin Head Chondrus by 146% and had no effect on growth rate or nitrogen and carbon removal by P. palmata and Charlesville Chondrus. Growth and yield of Basin Head Chondrus under intermittent aeration were over two times greater than both Charlesville Chondrus treatments. © 2014, Springer Science+Business Media Dordrecht.

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