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Hugh A. Poston

Publications and source records attributed to Hugh A. Poston.

4 recordsLinked to original sources
USGS1980

Effects of diet on survival and growth of the Atlantic silverside

Effects of two live and seven prepared diets on the survival and growth of postlarval and juvenile Atlantic silversides ( Menidia menidia ) were determined. Two experiments were conducted, one with 23-day-old postlarvae and one with 57-day-old juveniles. In both experiments, growth rate and survival were greatest on the live diet of brine shrimp ( Artemia salina ) nauplii. Survival was lowest on a prepared diet originally designed for freshwater fish species. Growth was similarly low for all lots fed prepared diets . A commercial flake food was the best of the prepared diets tested. Response to the diet was more sensitively reflected in growth than in survival . Younger fish showed a greater and more immediate growth response to diets than did juveniles. Postlarval fish that were fed brine shrimp gained 36.6 mg (from an initial body wet weight of 9.3 mg), whereas those fed the flake diet gained 4.5 mg. The reduced growth and survival of fish fed the artificial diets cannot be attributed to a single nutritional deficiency.

Progressive Fish-Culturist↗
USGS1976

Vitamin E and selenium interrelations in the diet of Atlantic salmon (Salmo salar): Gross, histological and biochemical deficiency signs

Either simultaneous or separate dietary deficiencies of vitamin E and selenium in Atlantic salmon during first 4 weeks of feeding caused twice the mortality shown in fish fed both supplemental vitamin E (0.5 IU/g dry diet) and selenium (0.1 µg/g). Subsequent dietary repletion with both vitamin E and selenium significantly reduced mortality during the following 2 weeks. Larger salmon (0.9 g initial mean weight), with vitamin E deficiency with or without selenium resulted in the following deficiency signs: extreme anemia, pale gills, anisocytosis, poikilocytosis, elevated plasma protein, exudative diathesis, dermal depigmentation, in vitro ascorbic acid-stimulated peroxidation in hepatic microsomes, yellow-orange liver color, yellow-brown intestinal contents, enlarged gall bladder distended with dark green bile, low vitamin E in carcass and hepatic tissue, muscular dystrophy, increased carcass fat and water, and a response to handling characterized by a transitory fainting with interruption in swimming. A deficiency of dietary selenium suppressed plasma glutathione peroxidase activity. Supplemental selenium with vitamin E significantly increased tocopherol activity in hepatic, but not carcass tissues. Supplements of both vitamin E and selenium were necessary to prevent muscular dystrophy.

Journal of Nutrition↗