Effect of .ALPHA.-tocopherol deficiency on carp. VII. The relationship between dietary levels of linoleate and .ALPHA.-tocopherol requirement.

Abstract

Feeding experiments were conducted to investigate the relationship between the requirement for tocopherol and dietary linoleate levels in carp. The results obtained in the feeding experiments showed that the elevated dietary linoleate levels increase the tocopherol requirement of carp, judging from the appearance of apparent muscular dystrophy. The fish receiving the diet with α-tocopherol content less than 10mg per 100g diet at the 5% linoleate level showed apparent muscular dystrophy and gained less body weight than those receiving diets enriched with the vitamin at levels exceeding 30mg per 100g diet. The weight gain of the carp receiving from 10-15% linoleate at a fixed level of 10mg α-tocopherol was low and 35-40% of the fish exhibited apparent muscular dystrophy. The fat-free and α-tocopherol deficient diets resulted in decreases in 18:2ω6, 20:4ω6 and 22:5ω6, the former diet also result in a marked increase of 16:1, 18:1 and 20:3ω9. Linoleic acid supplements gave increases in 18:2ω6, 20:4ω6 and 22:5ω6 and decreases in 16:1, 18:1 and 20:3ω9, while there were no marked changes in fatty acid distribution attributable to presence of increasing levels of tocopherol in the diet.