Subcutaneous Adipose Fatty Acid Profiles and Related Rumen Bacterial Populations of Steers Fed Red Clover or Grass Hay Diets Containing Flax or Sunflower-Seed

摘要: Steers were fed 70∶30 forage∶concentrate diets for 205 days, with either grass hay (GH) or red clover silage (RC), and sunflower-seed (SS) flaxseed (FS), providing 5.4% oil in the diets. Compared to containing SS, FS had elevated (P<0.05) subcutaneous trans (t)-18:1 isomers, conjugated linoleic acids n-6 polyunsaturated fatty acid (PUFA). Forage oilseed type influenced total n-3 PUFA, especially α-linolenic (ALA) non-conjugated diene biohydrogenation (BH) fat proportions being greater GH as compared SS RC. Of 25 bacterial genera impacted by diet, 19 correlated (FA) profile. Clostridium most abundant when levels of linolenic acids, PUFA's found be lowest fat, suggestive their role BH. Anerophaga, Fibrobacter, Guggenheimella, Paludibacter Pseudozobellia more rumen VA low. This study clearly shows impact oilseeds forage source on deposition FA beef cattle. Significant correlations between specific maybe indicative determining profile adipose tissue. However, despite numerous correlations, dynamics bacteria BH unsaturated synthesis PUFA tissue profiles require further experimentation determine if these are consistent over a range differing composition. Present results demonstrate that order achieve targeted beef, multifactorial approach will required takes into consideration not only but also non-oil fraction level feed processing, microbes acid.