Time filter

Source Type

United Kingdom

Robson A.A.,University of Western Brittany | Robson A.A.,Ardtoe Marine Laboratory
Nutrition and Health | Year: 2011

It is crucial that emergent technologies create foods that help prevent the causal mechanisms of the diet induced disease epidemic. Food nanotechnology could create modern convenience foods that mimic and improve on the nutritional value of the most nutritious cooked wild foods for humans. Structuring a solid processed food similar to a celery stalk using selfassembled, water-filled, edible nanocells or nanotubes would substantially lower its energy density (<1.6 kcal g"1).Food technologists could harness the natural turgor force to produce a firm chocolate bar, biscuit or breakfast cereal with a good bite, without altering the appearance or taste of the product. Water carriesflavour with few calories, and taste sensation per mouthful could be improved by processing food on the nanoscale to increase the surface area that is in contact with taste and smell receptors. The bioavaiiable nutrient content (including cofactors) of processed foodscould be increased by existing bioactive nanoencapsulation. This would allow people to continue to consume modern convenience food on a mass scale, while simultaneously and significantly increasing nutrient intake and reducing energy intake per day. Thus, helping to reduce mental ill health, obesity and other postprandial insults. © 2011 A B Academic Publishers. Source

The stress and trauma associated with handling and movement of fish may have welfare implications and may also increase susceptibility to disease post-transfer. Juvenile salmonids have been transported live from hatchery to production grow out units for some time but little information is available on the live transport of marine finfish species such as Atlantic cod, Gadus morhua L. The present study examines the accumulation of un-ionised ammonia (UIA-N) in live transport of juvenile cod and examines the effectiveness of aeration, an ammonia absorbing agent and duration of fast period in controlling the level of UIA-N. UIA-N increased significantly with higher stocking densities in simulated transports of 24h duration, from 0.08μgl-1 at 10kgm-3 to 0.43μgl-1 at 30kgm-3, and also with duration of the simulated transports, rising from 1.14μgl-1 after 3h to 6.01μgl-1 at 24h in a second trial. Average UIA-N was significantly higher when diffuse aeration with air as well as oxygenation was used, 9.03μgl-1 compared with 1.54μgl-1 with oxygenation only. Air diffusion had the effect of maintaining a higher pH which consequently increased the potential for ammonia toxicity. Mean ammonia level was significantly less at 3.17μgl-1 in a simulated 24h transport when an ammonia absorbing product was used compared with 6.01μgl-1 l UIA-N in control tanks. This additive would be beneficial during transports of marine finfish for the regulation of ammonia. The effects of varying fast periods and related duration of gut evacuation in juvenile cod on water chemistry including ammonia levels were also assessed. From this an optimum fast period of 36h for live transport of cod at 12°C is recommended. Stocking densities of up to 30kgm-3 did not give rise to toxic levels of ammonia. Aeration in addition to oxygenation, while increasing pH, leads to elevated ammonia, but ammonia accumulation can be reduced by using an absorbing agent. © 2010 Elsevier B.V. Source

Bravo S.,Austral University of Chile | Treasurer J.,Ardtoe Marine Laboratory | Sepulveda M.,Salmones Ventisqueros | Lagos C.,Austral University of Chile
Aquaculture | Year: 2010

Hydrogen peroxide (H2O2) was the only effective alternative treatment to emamectin benzoate (EMB, SLICE, Schering Plough) for the sea louse Caligus rogercresseyi in Chile during the period from February to September 2007. This introduction was due to the loss of sensitivity of lice to EMB after 7 years of exclusive use. A detailed field appraisal of treatments was carried out on salmon farms at two sites near Puerto Montt (Lat 42oS) in August 2007 to evaluate the efficacy of hydrogen peroxide in the control of C. rogercresseyi. A skirt was used on one farm for treatments and an enclosed tarpaulin in the other. Hydrogen peroxide was applied by bath at a concentration of 1.5 g l-1 for 20 min treatment but this did not kill C. rogercresseyi. Most of the parasites recovered from the treatment and were available to infest new hosts. Treatments were carried out in tanks under laboratory conditions to test the findings obtained in the field and these gave similar results. Caligus recovered completely after 30 min post treatment. © 2010 Elsevier B.V. All rights reserved. Source

Treasurer J.,Ardtoe Marine Laboratory | Feledi T.,Research Institute for Fisheries
Journal of the World Aquaculture Society | Year: 2014

Several indices were examined to assess the physical condition of wrasse stocked on Atlantic salmon, Salmo salar, farms as cleaner fish, and included examination of eye condition, snout erosion, skin hemorrhaging, and erosion and splitting of dorsal, pectoral, anal and caudal fins. Baseline values were determined for five wrasse species: goldsinny, Ctenolabrus rupestris; rock cook, Centrolabrus exoletus; corkwing, Crenilabrus melops; cuckoo, Labrus mixtus; and ballan, Labrus bergylta, held in a farm environment for 3 mo prior to transfer to salmon farms. The caudal fin was most affected by injury. The fin erosion index (FEI) was low in all species and below 0.6. The fin splitting index (FSI) was the most prominent index and was significantly higher in the caudal fin (FSI>2) compared with other fins (FSI<0.5), and also significantly higher in corkwing and rock cook compared with the other wrasse species. The FEI and FSI were also calculated for a group of ballan wrasse before stocking on a seawater farm, during the first winter and upon harvesting. There were no significant differences in the scores of fin erosion and fin splitting in any of the samples, although the indices were marginally poorer in winter. © by the World Aquaculture Society 2014. Source

Treasurer J.W.,Ardtoe Marine Laboratory | Bravo S.,Austral University of Chile
Aquaculture | Year: 2011

The location of attached and mobile stages of Caligus rogercresseyi and C. elongatus on Atlantic salmon Salmo salar hosts was compared with that of the distribution patterns of Lepeophtheirus salmonis. The distribution of C. rogercresseyi was also compared in experimental and natural infections, and there were no significant differences for either attached or mobile stages between infection routes. Most C. rogercresseyi chalimi were located on the abdomen and post anal areas. Although the distribution of mobile stages was more homogenous there was a significantly higher percentage on the post anal area, 35% of all mobiles, compared with the salmon surface in the post anal region of only 3%. Significantly more attached stages, from 70 to 75%, of both Caligus species were located on the fins compared with mobiles. The mobile stages of both Caligus species had a predilection for the abdominal body. A higher percentage of attached stages of C. elongatus was located on the ventral fins and tail compared with C. rogercresseyi and, in contrast,significantly more were present on the body in C. rogercresseyi. However, there was no difference in the distribution of mobile stages of the two Caligus species with a significantly higher percentage located on the abdomen. In contrast, mobile L. salmonis were predominantly located on the back and head. Significantly more attached stages of L. salmonis were present on the dorsal fins and adjoining basal epidermis, 30% comparedwith <. 2% in the Caligus species. These results suggest that C. rogercresseyi and C. elongatus show similar preferences for the host ventral body and fin locations and there is no direct competition for host substrate between C. elongatus and L. salmonis. © 2011 Elsevier B.V. Source

Discover hidden collaborations