scholarly journals Watercress (Nasturtium officinale) production utilizing brook trout (Salvelinus fontinalis) flow-through aquaculture effluent

2007 ◽  
Author(s):  
Erika Nichole Smith
1973 ◽  
Vol 30 (12) ◽  
pp. 1811-1817 ◽  
Author(s):  
Roger O. Hermanutz ◽  
Leonard H. Mueller ◽  
Kenneth D. Kempfert

The toxic effects of captan on survival, growth, and reproduction of fathead minnows (Pimephales promelas) and on survival of bluegills (Lepomis macrochirus) and brook trout (Salvelinus fontinalis) were determined in a flow-through system. In a 45-week exposure of fathead minnows, survival and growth were adversely affected at 39.5 μg/liter. Adverse effects on spawning were suspected but not statistically demonstrated at 39.5 and 16.5 μg/liter. The maximum acceptable toxicant concentration (MATC), based on survival and growth, lies between 39.5 and 16.5 μg/liter. The lethal threshold concentration (LTC) derived from acute exposures was 64 μg/liter, resulting in an application factor (MATC/LTC) between 0.26 and 0.62. LTC values for the bluegill and brook trout were 72 and 29 μg/liter, respectively. The estimated MATC is between 44.6 and 18.7 μg/liter for the bluegill and between 18.0 and 7.5 μg/liter for the brook trout.The half-life of captan in Lake Superior water with a pH of 7.6 is about 7 hr at 12 C and about 1 hr at 25 C. Breakdown products from an initial 550 μg/liter of captan were not lethal to 3-month-old fathead minnows.


1975 ◽  
Vol 32 (5) ◽  
pp. 609-613 ◽  
Author(s):  
Paul M. Mehrle ◽  
Foster L. Mayer Jr.

Twenty-two days before hatching, eyed eggs of brook trout (Salvelinus fontinalis) were placed in a flow-through system and continuously exposed to toxaphene (0, 39, 68, 139, 288, and 502 ng/liter) until they hatched and the resulting fry were exposed for a further 90 days. Hatchability was not affected by toxaphene, but all of the fry exposed to 502 and 288 ng/liter of toxaphene died by 30 and 60 days after hatch, respectively. Growth of fry was significantly depressed at the 139 and 288 ng/liter concentrations 30 days after hatch and at all concentrations after 60 and 90 days of toxaphene exposure.Whole body collagen of fry, as estimated by hydroxyproline, was significantly decreased in the four higher concentrations of toxaphene within 7–15 days after hatch. Backbone collagen was significantly decreased (P < 0.05) in 30-, 60-, and 90-day-old fry exposed to toxaphene, whereas calcium and phosphorus concentrations in the backbone were increased (P < 0.05). The mineral: collagen ratio was significantly increased by toxaphene. The whole body collagen of sac-fry was a good predictor of later growth and development of brook trout.


1988 ◽  
Vol 45 (9) ◽  
pp. 1587-1596 ◽  
Author(s):  
C. M. Wood ◽  
D. G. McDonald ◽  
C. E. Booth ◽  
B. P. Simons ◽  
C. G. Ingersoll ◽  
...  

Brook trout (Salvelinus fontinalis) adapt to chronic sublethal acid/Al stress. The accompanying acclimation confers greater resistance to short-term increases in Al and acidity. Adult trout were exposed in flowing soft water to eight combinations of pH (6.5, 5.2) × Ca2+ (25, 400 μequiv/L) × Al (0, 75, 150 μg/L = 0, 2.8, 5.6 μmol/L). After 10 wk, blood sampling by caudal puncture revealed no significant variations in osmolality, plasma protein, or hemoglobin and only minor differences [Formula: see text] in plasma Na+ and Cl−. Overall, most electrolytes were higher in fish exposed to higher water Al and/or Ca2+; only plasma Ca2+ was directly depressed by low pH. Hematocrit was raised by both low pH and elevated Al. When trout naive to both acid and Al were challenged with pH = 4.8, Al = 333 μg/L under flow-through conditions, there were large negative whole-body Na+ fluxes and marked depressions of plasma Na+ and Cl−, hemoconcentration, and substantial mortality over 48 h. Prior exposure for 10 wk to pH = 5.2 plus either 75 or 150 μg Al/L prevented mortality and ameliorated or abolished these effects through a more rapid recovery of net Na+ balance. Prior exposure to pH = 5.2 alone ameliorated these effects only slightly.


1988 ◽  
Vol 45 (9) ◽  
pp. 1575-1586 ◽  
Author(s):  
C. M. Wood ◽  
R. C. Playle ◽  
B. P. Simons ◽  
G. G. Goss ◽  
D. G. McDonald

The relative importance of ionoregulatory and respiratory disturbances in brook trout (Salvelinus fontinalis) under acid/Al stress in soft water is dependent upon water pH and Ca2+ levels. Trout acclimated to Ca2+ = 25 or 400 μequiv/L were fitted with arterial catheters and exposed to acid/Al for 10 d under flow-through conditions. Parameters monitored included pHa, [Formula: see text], [Formula: see text], HCO3−, ΔH+m, Na+, Cl−, K+, Ca2+, protein, lactate, glucose, hemoglobin, and hematocrit. Exposure to pH = 4.8 (no Al) at Ca2+ = 25 μequiv/L caused no mortality and negligible physiological disturbance. Addition of Al (333 μg/L or 12.3 μmol/L) resulted in >80% mortality (LT50 = 39.0 h) preceded by a marked decrease of plasma Na+ and Cl−, a moderate disturbance of blood gases, but no acidosis. At higher Ca2+ (400 μequiv/L), this same exposure (pH = 4.8, Al = 333 μg/L) caused similar mortality (LT50 = 38.5 h) but smaller ionic disturbances, much larger decreases in blood O2, increases in blood CO2, and respiratory acidosis. Exposure to pH = 4.4 (no Al) at Ca2+ = 25 μequiv/L caused 60% mortality (LT50 = 170.0) preceded by marked ionic disturbances and metabolic acidosis, but little change in blood gases. Addition of Al (333 μg/L) increased mortality to >80% (LT50 = 78.2 h) with smaller ionic but greater respiratory disturbances.


Parasitology ◽  
1982 ◽  
Vol 85 (3) ◽  
pp. 495-501 ◽  
Author(s):  
P. Brassard ◽  
M. E. Rau ◽  
M. A. Curtis

Guppies (Lebistes reticulatis) exposed to doses as low as 25 cercariae of Diplostomum spathaceum for 30 min were consistently and significantly more susceptible to predation by brook trout (Salvelinus fontinalis) than uninfected controls. The increase in susceptibility to predation was correlated with a marked decrease in the activity of infected fish.


2016 ◽  
Vol 73 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Elsa Goerig ◽  
Theodore Castro-Santos ◽  
Normand Émile Bergeron

Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15 °C. Passage was impeded at higher flows, through culverts with steep slopes, and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.


1972 ◽  
Vol 29 (11) ◽  
pp. 1615-1624 ◽  
Author(s):  
James E. Bryan ◽  
P. A. Larkin

Analyses of stomach contents showed that the kinds of prey eaten by brook trout (Salvelinus fontinalis), cutthroat trout (Salmo clarki), and rainbow trout (Salmo gairdneri) were seldom distributed at random among the individuals. Repeated observation of food eaten by individuals in a stream and ponds showed that prey types were eaten in proportions which were characteristic for an individual.Specialization occurred on several different kinds of prey. Although the degree of specialization was higher during shorter intervals, the data suggested that some specialization persisted for half a year. There were no striking correlations between degree of specialization and other individual properties such as size, growth rate, weight of food, number of food items, previous specialization, or area of recapture.In addition to the observations on trout in relatively undisturbed habitats, a field experiment was conducted using laboratory-reared rainbow trout held in small ponds. The food of each trout in the experiment was sampled repeatedly. In analysis of variance, interaction among the individuals and kinds of prey eaten showed that food specialization occurred. Both the absolute and relative abundance of potential prey were constant during the experiment.


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