Alteration Tests of the Abernathy Salmon Diet, 1971
Alteration Tests of the Abernathy Salmon Diet, 1971

Author: Laurie G. Fowler

Publisher:

Published: 1972

Total Pages: 16

ISBN-13:

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Feeding trials using fall chinook salmon finglerlings were conducted at the Salmon Cultural Laboratory, Longview, Washington, during 1971 for the purpose of improving the Abernathy diet formula. The results indicated that cottonseed meal could replace a portion of the fish meal in the diet without reducing fish growth, but similar substitutions of wheat and corn gluten meal reduced growth. Fish growth was significantly increased when a diet containing 50 percent protein and 3,350 kcal per kilogram was fed as compared with a diet containing 45 percent protein and 3,350 kcal per kilogram. Soybean lecithin proved to be equal to soybean oil as a caloric source when fed at 2 percent of the diet. Two types of dried whey product with different levels of lactose content produced similar growth response. Reducing the dried whey portion of the diet to 5 percent did not affect growth, nor did methionine supplementation produce any effects. Anchovy meal was unsuitable as a replacement for herring meal.

Alteration Tests of the Abernathy Salmon Diet, 1971
Alteration Tests of the Abernathy Salmon Diet, 1971

Author: United States. Bureau of Sport Fisheries and Wildlife

Publisher:

Published: 1972

Total Pages: 35

ISBN-13:

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Feeding trials using fall chinook salmon finglerlings were conducted at the Salmon Cultural Laboratory, Longview, Washington, during 1971 for the purpose of improving the Abernathy diet formula. The results indicated that cottonseed meal could replace a portion of the fish meal in the diet without reducing fish growth, but similar substitutions of wheat and corn gluten meal reduced growth. Fish growth was significantly increased when a diet containing 50 percent protein and 3,350 kcal per kilogram was fed as compared with a diet containing 45 percent protein and 3,350 kcal per kilogram. Soybean lecithin proved to be equal to soybean oil as a caloric source when fed at 2 percent of the diet. Two types of dried whey product with different levels of lactose content produced similar growth response. Reducing the dried whey portion of the diet to 5 percent did not affect growth, nor did methionine supplementation produce any effects. Anchovy meal was unsuitable as a replacement for herring meal.

Toxicity of Three Herbicides (butyl, Isooctyl, and Propylene Glycol Butyl Ether Esters of 2,4-D) to Cutthroat Trout and Lake Trout
Toxicity of Three Herbicides (butyl, Isooctyl, and Propylene Glycol Butyl Ether Esters of 2,4-D) to Cutthroat Trout and Lake Trout

Author: D. F. Woodward

Publisher:

Published: 1978

Total Pages: 12

ISBN-13:

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Two formulations of the herbicide 2,4-D (2,4-dichlorophenoxyacetic acid) - the butyl ester (BE) and the propylene glycol butyl ether ester (PGBEE) -- had 96-h LC50's to cutthroat trout and lake trout ranging from 490 to 1,200 microgram/liter in static tests. A third formulation -- the isooctyl ester (IE) -- was not toxic to cutthroat trout or lake trout at concentrations below 60.000 microgram/liter. The butyl ester (2,4-D BE) was slightly more toxic than 2,4-D PGBEE, and the toxicity of both esters increased as water temperature decreased.

Food of Alewives, Yellow Perch, Spottail Shiners, Trout-perch, and Slimy and Fourhorn Sculpins in Southeastern Lake Michigan
Food of Alewives, Yellow Perch, Spottail Shiners, Trout-perch, and Slimy and Fourhorn Sculpins in Southeastern Lake Michigan

Author: LaRue Wells

Publisher:

Published: 1980

Total Pages: 20

ISBN-13:

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Stomachs of 1,064 alewives, 1,103 yellow perch, 246 spottail shiners, 288 trout-perch, 454 slimy sculpins, and 562 fourhorn sculpins from Lake Michigan were examined for food contents. Fish were sampled primarily from March to November and nearly all were caught at the bottom in the southeastern part of the lake near Saugatuck, Michigan. Pontoporeia was the most commonly reprented food item in the stomach contents of the fish examined, with immature midges, Mysis (a type of freshwater shrimp), copepods, cladocerans, fingernail clams and crayfish also being represented. Different species consumed different proportions of foods. Zooplankton was the principle food of alewives and spottail shiners, but was also consumed in small quantities by yellow perch and trout perch. Mysis was important to fourhorn sculpins, in addition to Pontoporeia. Immature midges were a major portion of spottail shiners and trout perch, also being consumed by alewives. Fish were often the most important food of yellow perch in the largest size category. Crayfish were a sizable portion of the diet of yellow perch on rocky bottoms, but sparingly on smooth bottoms. Spottail shiners also ate substantial numbers of fingernail clams.

The Razorback Sucker, Xyrauchen Texanus, in the Upper Colorado River Basin, 1974-76
The Razorback Sucker, Xyrauchen Texanus, in the Upper Colorado River Basin, 1974-76

Author: Charles W. McAda

Publisher:

Published: 1980

Total Pages: 22

ISBN-13:

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The razorback sucker, which has declined in abundance in the upper Colorado River primarily because of man's impact on the environment, has been recommended for listing as "threatened" in the U.S. Department of Interior's list of threatened or endangered species. During the present investigation, razorback suckers were nevertheless found in relatively large concentrations at two restricted locations -- the mouth of the Yampa River and a flooded gravel pit connected to the Colorado River near Grand Junction, Colorado.