Studies on the nutrition of marine flatfish. The pyridoxine requirement of turbot ( Scophthalmus maximus )
1. Diets containing graded levels of pyridoxine hydrochloride (to supply 0.26–30 mg pyridoxine/kg) were given to seven duplicate groups of turbot ( Scophthalmus maximus ) for 12 weeks and their growth rate was measured during this period. 2. Good growth was obtained on all treatments except those gr...
| Published in: | British Journal of Nutrition |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
1978
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1079/bjn19780121 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0007114578000379 |
| Summary: | 1. Diets containing graded levels of pyridoxine hydrochloride (to supply 0.26–30 mg pyridoxine/kg) were given to seven duplicate groups of turbot ( Scophthalmus maximus ) for 12 weeks and their growth rate was measured during this period. 2. Good growth was obtained on all treatments except those groups given less than 1.0 mg pyridoxine/kg diet. These fish grew normally until weeks 8–10 but thereafter their weight gain was significantly less than that for other treatments. 3. Measurements of aspartate aminotransferase ( EC 2.6.1.1) in muscle and liver and of alanine aminotransferase ( EC 2.6.1.2) in liver of the turbot showed that the activities of these enzymes increased with increasing dietary pyridoxine intake up to a level of 2.5 mg pyridoxine/kg. The activities of these enzymes were not further enhanced by additional dietary pyridoxine. 4. Percentage stimulation of these enzymes by pre-incubation of extracts with pyridoxal phosphate was minimal with those groups of turbot given 2.5 mg pyridoxine/kg diet or more. 5. It is concluded that the dietary requirement of turbot for vitamin B 6 can be safely met with a diet containing between 1.0 and 2.5 mg pyridoxine/kg. 6. An eighth group of turbot given the pyridoxine antagonist 4-deoxypyridoxine hydrochloride (20 mg/kg) showed retarded growth after 2 weeks, together with a high mortality rate. |
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