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Impact of nutrition and salinity changes on biological performances of green and white sturgeon.

Vaz PG, Kebreab E, Hung SS, Fadel JG, Lee S, Fangue NA - PLoS ONE (2015)

Bottom Line: Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted.Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables.Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Science, University of California Davis, Davis, California, United States of America.

ABSTRACT
Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD.

No MeSH data available.


Related in: MedlinePlus

Experimental design.First phase (top): Four levels of one treatment, feeding rate (12.5, 25, 50, 100%). Second phase (bottom): Four levels of the treatment salinity (0, 8, 16, 24/32 ppt), and three levels of the exposure time to salinity levels (12, 72, 120 h). The experimental design was the same for the two species, except that maximum salinity was different for white (W) and green (G) sturgeon.
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pone.0122029.g001: Experimental design.First phase (top): Four levels of one treatment, feeding rate (12.5, 25, 50, 100%). Second phase (bottom): Four levels of the treatment salinity (0, 8, 16, 24/32 ppt), and three levels of the exposure time to salinity levels (12, 72, 120 h). The experimental design was the same for the two species, except that maximum salinity was different for white (W) and green (G) sturgeon.

Mentions: This experiment phase was initiated at 214 and 189 days post hatch in green and white sturgeon, respectively, and was replicated similarly for the two species. For each species, 840 juvenile sturgeons (green: 174.0 ± 0.4 g, white: 173.2 ± 0.6 g; mean ± SE) were randomly chosen and released into 12 circular, flow through fiberglass ~787 L tanks, resulting in 70 fish per tank (Fig 1). Fish were acclimatized to the tanks for 8 days and fed at the OFR (2.0 mm sinking pellet, Skretting, Tooele, UT, USA). Feeds were given using a 24-h belt feeder to ensure continuous food availability [54]. Holding tanks were located outdoors and had a fiberglass cover with a hatch allowing access of feed and sunlight of natural photoperiod. An angled spray-bar supplied degassed well water (8–10 L min-1) to increase circulation and feed dispersion. Water temperature (18.1 to 18.7°C), dissolved oxygen (7.5 to 9.0 mg L-1), and ammonia (0.1 to 0.2 mg L-1) were maintained throughout the trial.


Impact of nutrition and salinity changes on biological performances of green and white sturgeon.

Vaz PG, Kebreab E, Hung SS, Fadel JG, Lee S, Fangue NA - PLoS ONE (2015)

Experimental design.First phase (top): Four levels of one treatment, feeding rate (12.5, 25, 50, 100%). Second phase (bottom): Four levels of the treatment salinity (0, 8, 16, 24/32 ppt), and three levels of the exposure time to salinity levels (12, 72, 120 h). The experimental design was the same for the two species, except that maximum salinity was different for white (W) and green (G) sturgeon.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4382339&req=5

pone.0122029.g001: Experimental design.First phase (top): Four levels of one treatment, feeding rate (12.5, 25, 50, 100%). Second phase (bottom): Four levels of the treatment salinity (0, 8, 16, 24/32 ppt), and three levels of the exposure time to salinity levels (12, 72, 120 h). The experimental design was the same for the two species, except that maximum salinity was different for white (W) and green (G) sturgeon.
Mentions: This experiment phase was initiated at 214 and 189 days post hatch in green and white sturgeon, respectively, and was replicated similarly for the two species. For each species, 840 juvenile sturgeons (green: 174.0 ± 0.4 g, white: 173.2 ± 0.6 g; mean ± SE) were randomly chosen and released into 12 circular, flow through fiberglass ~787 L tanks, resulting in 70 fish per tank (Fig 1). Fish were acclimatized to the tanks for 8 days and fed at the OFR (2.0 mm sinking pellet, Skretting, Tooele, UT, USA). Feeds were given using a 24-h belt feeder to ensure continuous food availability [54]. Holding tanks were located outdoors and had a fiberglass cover with a hatch allowing access of feed and sunlight of natural photoperiod. An angled spray-bar supplied degassed well water (8–10 L min-1) to increase circulation and feed dispersion. Water temperature (18.1 to 18.7°C), dissolved oxygen (7.5 to 9.0 mg L-1), and ammonia (0.1 to 0.2 mg L-1) were maintained throughout the trial.

Bottom Line: Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted.Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables.Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Science, University of California Davis, Davis, California, United States of America.

ABSTRACT
Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD.

No MeSH data available.


Related in: MedlinePlus