Milk C18:1and conjugated linoleic acid isomers from cows grazed on perennial ryegrass,tall fescue or timothy grass swards

摘要

Previous work at our institute has shown substantial variation in the degree of cell damage during ingestion and mastication of different grasses, resulting in differences in the release rate of nitrogen and lipid into rumen fluid (Kim et al.2008).These differences in the release rate of lipid may influence the extent of biohydrogenation in the rumen and consequently its intermediates C18 :1 and conjugated linoleic acid (CLA) and their concentration in ruminant products.This study investigated the C18 biohydrogenation intermediates of milk from cows grazing three contrasting grass species (perennial ryegrass, PRG ; tall fescue, TF ; and timothy, TIM) over two years.