Record Details
Field | Value |
---|---|
Title | Energy utilization by young grass carp fed different diets |
Names |
Cai, Zhengwei
(creator) Curtis, Lawrence R. (advisor) |
Date Issued | 1988-10-06 (iso8601) |
Note | Graduation date: 1989 |
Abstract | Effects of diet on food energy utilization by grass carp fed aquatic plants or formulated diets with varied lipid sources and levels are presented in three manuscripts. Significant effects of diet on food consumption, digestion, growth and muscle fatty acid (FA) composition of fingerling diploid grass carp fed aquatic macrophytes or a commercial catfish feed are reported in Chapter 1. Daily ration consumed exceded body weight in fish fed Elodea at 26°C. This resulted in excellent growth and growth was positively related to the daily intake of protein by fish fed different diets. Grass carp extensively elongated and desaturated dietary linolenic acid into long chain polyunsaturated fatty acids (PUFA). When juvenile triploid grass carp were fed Elodea, high consumption, growth rate and tissue n-3 FA levels were found. Consumption and growth of these fish, but not digestion efficiency, increased with environmental temperature (Chapter 2). In addition, a drop in growth rate coincident with decreased tissue n-3 FA levels occured at 14.4, 18.8, and 24.4°C in fish fed Elodea for 42 days and then fed catfish feed for 33 more days. Responses of fish muscle and liver FA composition to temperature were also examined. In Chapter 3, effects of dietary lipid sources and levels on energy utilization by grass carp were examined. Energy budgets for juvenile diploid grass carp fed Elodea or one of the three formulated diets with varied lipid levels were determined and compared. Growth rate, fecal energy loss and apparent heat increment were empirically related to ration size. High fecal energy losses and low metabolic cost are the general features of the energy budgets for those fish. Increasing of dietary lipid content up to about 6% resulted in better energy utilization and growth. A diet with low linoleic acid and high n-3 polyunsaturated fatty acid levels (salmon oil) inhibited appetite of fish and led to poor growth. When dietary linoleic acid supply was sufficient, addition of linolenic acid and n-3 PUFA in diets improved energy utilization and growth in diploid grass carp. |
Genre | Thesis/Dissertation |
Topic | Ctenopharyngodon idella |
Identifier | http://hdl.handle.net/1957/39072 |