Omega-3 fatty acid incorporation in fat and muscle tissues of growing pigs, fed supplements of fish oil.

Fifteen pigs from two litters of Norwegian Landrace were divided into three groups of five animals. The pigs were fed individually the same basic diet for 64 days, one group serving as control, the two other groups receiving daily supplements of 5 and 20 g fish oil, respectively. Biopsies were taken from subcutaneous fat and muscle tissues on day 0, 3, 8, 16 and 32. Samples were also collected from animals slaughtered on days 64 and 78. In fat tissue from pigs given a daily dose of 20 g fish oil containing 30% eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as triglycerides, the concentrations of EPA and DHA were significantly increased above the levels in the control animals over the 32 days period. Unexpectedly, there was also a significant increase in docosapentaenoic acid (DPA), in spite of the very low level of this fatty acid in the fish oil. In fat tissue from pigs given 5 g fish oil the contents of EPA and DPA were significantly increased. Also in muscle tissue from pigs given a daily dose of 20 g fish oil, the concentration of EPA, DPA and DHA were significantly elevated above the level of the control group over the 32 days period. In muscle tissue from pigs given 5 g fish oil only the contents of EPA were significantly increased. There was a positive correlation between the dose of fish oil and the concentrations of omega-3 polyunsaturated fatty acids in both fat and muscle tissues.(ABSTRACT TRUNCATED AT 250 WORDS)