碩士 / 國立海洋大學 / 食品科學系 / 88 / The first study was to investigate the utilization of carbohydrate and the protein-sparing effect by different carbohydrates in juvenile malabar grouper (Epinephelus malabaricus). White fish meal of dietary protein was incorporated into the diet providing 50, 46 and 42% of dietary protein. The carbohydrate sources were starch and glucose. After 8 weeks of feeding, weight gain of glucose-fed and starch-fed fish were similar (p>0.05) at each dietary protein level. Weight gain of fish decreased with increasing dietary glucose content. In the starch group, weight gain of 50% protein-fed fish was significantly (p<0.05) higher than 46 and 42% protein-fed fish. Body lipid content, lipid and energy deposition of starch-fed fish were significantly higher than glucose-fed fish at 50% dietary protein level. Fish fed glucose diet had higher plasma glucose concentration than fish fed starch diet at 46 and 42% protein level. The hepatosomatic index (HSI) of glucose-fed fish was higher than starch-fed fish, but the glycogen content was not different in either glucose or starch-fed fish. At 50 and 46% dietary protein levels, fish fed starch diet had higher hepatic hexokinase (HK) and phosphofructokinase (PFK) activities than fish fed glucose diet. Starch-fed fish had lower hepatic glucose-6-phosphatase (G6Pase) activities than glucose-fed fish at 46 and 42% protein levels. These results suggest that carbohydrate inclusion level in grouper diet should not exceed 20% and that starch could spare some protein when the dietary protein level is sub-optimum.
The second study was to investigate the effects of feeding strategy on carbohydrate utilization in juvenile malabar grouper. White fish meal was incorporated into the diet providing 50 and 44% of dietary protein. Carbohydrate sources were glucose and starch. Fish were fed in three different frequencies namely, two meals (2M), six meals (6M) and continuous feeding (CF) per day. After 8 weeks, weight gain of starch-fed fish was significantly (p<0.05) higher than glucose-fed fish fed 2M or 6M at each dietary protein level. In the glucose-fed group, weight gain of CF fish were higher than 2M and 6M fish at each dietary protein level; in the starch-fed group, weight gain of 6M and CF fish were higher than 2M fish at 44% dietary protein level. In the starch-fed group, no difference in weight gain was observed between 44 and 50% protein diets when the fish were fed CF. HSI of the glucose-fed fish was higher than starch-fed fish regardless of feeding strategy and dietary protein level. The hepatic HK and PFK activities increased with increasing feeding frequency. Hepatic aspartate transaminase (AST) and alanine transaminase (ALT) activities were higher in glucose-fed fish than in starch-fed fish. These results suggest that starch is better utilized than glucose by grouper and both utilization are improved as feeding frequency increased. The study also demonstrates that starch could spare some dietary protein level in grouper diet when the fish were fed continuously.
| Identifer | oai:union.ndltd.org:TW/088NTOU0253006 |
| Date | January 2000 |
| Creators | Yu-Hong Lin, 林鈺鴻 |
| Contributors | Shi-Yen Shiau, 蕭錫延 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 106 |
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