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J. W. Meade

Publications and source records attributed to J. W. Meade.

29 records · Page 2Linked to original sources
USGS1986

Review of the intensive culture of walleye fry

Efficient intensive culture of larval walleyes (Stizostedion vitreum) may soon be realized due to results of research on larval development, culture environment, preferred food organisms, and feeding techniques. Larval behavior and morphology (developmental state) can be used as indicators for appropriate handling and feeding techniques. Certain environmental conditions such as a rearing unit color that contrasts with food organisms, water temperatures of 18‐22°C, uniform lighting, and a stocking density of no more than 35,000 fish/m 3 reportedly contribute to increased growth and survival. Successful culture requires that suitable food such as cladocerans, copepods, and brine shrimp be continuously available at a high density (0.1 organism/mL). Cannibalism among walleye larvae has not been prevented but has been reduced through the use of suitable fish and food densities.

Progressive Fish-Culturist↗
USGS1985

Allowable ammonia for fish culture

A review of the published literature on effects of ammonia on fish indicates that un‐ionized ammonia alone is probably not the cause of gill hyperplasia, indicative of, or previously attributed to, chronic ammonia poisoning. The maximum safe concentration of un‐ionized ammonia is unknown, but in many cases it is not close to the 0.0125 mg/L value commonly accepted by fish culturists.

Progressive Fish-Culturist↗
USGS1985

Gill lamellar dilations (Telangiectasis) related to sampling techniques

Among fish killed by concussion (a blow to the head), lake trout Salvelinus namaycush readily developed telangiectasis, lamellar edema, and hemorrhagic thymi; Atlantic salmon Salmo salar and rainbow trout Salmo gairdneri developed thymic hemorrhages but few or no gill lesions. This illustrates a potentially overlooked bias that sampling techniques can cause in histologic analyses.

Transactions of the American Fisheries Society↗
USGS1983

Effect of temperature on production of tiger muskellunge in intensive culture

Tiger muskellunge ( Esox masquinony × E. lucius ) juveniles were reared at constant temperatures in the temperature range 14–28°C. For fish 3–4 cm long, growth, production and feed conversion efficiency were greatest at 20–22°C. Survival was reduced and unaccountable mortality (cannibalism index) was greatest at 24°C. Growth per unit of temperature was about equal over the range 16–22°C. For fish 12–13 cm long, feed conversion efficiency and mean individual growth were greatest at 23°C; growth per unit of temperature was nearly equal over the range 20–24°C.

Aquaculture↗
USGS1983

Changes in phototaxis during early development of walleye

Phototaxis of walleyes Stizostedion vitreum vitreum was examined during the first 11 weeks of larva and juvenile development. Fish were subjected to six light intensities ranging from 2 to 34 lux, plus 7,800 lux as an extreme. The number of fish positioned in each light intensity was used to determine the phototactic response. Larvae and juveniles 1 to 8 weeks old (9 to 32 mm total length) were attracted to the highest light intensity (7,800 lux), and juveniles older than 8 weeks (32 to 40 mm long) aggregated at the lowest intensities (2 and 4 lux). The change from positive to negative phototaxis was more closely related to fish size than to age.

Transactions of the American Fisheries Society↗