2021 Volume 74 Issue 5 Pages 303-309
Recently, Japanese black beef farms have grown to a large scale and have become highly densified. Marbling beef is produced by supplying a large amount of concentrated feed from early in the life of the cattle. As a result, chronic febrile illnesses such as respiratory diseases, arthritis, and otitis media are increasing, and it is speculated that immunity may deteriorate due to the special feeding. In this study, we investigated the dynamics of blood fatty acids, which are attracting attention as an immunomodulatory nutrient, in 120 Japanese black female fattening cattle aged 9 to 30 months. The amount of linoleic acid (LA), an omega-6 fatty acid, increased significantly in the early middle stage of fattening and remained high until the finishing stage, but arachidonic acid (AA) was almost unchanged. Eicosapentaenoic acid (EPA), an omega-3 fatty acid, showed a significant decrease after the early middle stage of fattening, revealing an increase in the omega-6/omega-3 ratio.
