Milk, meat and eggs tend not to be regarded as an important source of PUFA. They are
disproportionally high in SFA compared with their PUFA content, especially those from
cattle and sheep, since their rumen microbes are responsible for the loss of over 90% of
PUFA intake by livestock. This need not necessarily be the case since the relative proportion
of PUFA in these foods is dictated by livestock management, especially feeding, and this
can be manipulated to boost their content of crucial long-chain n-3 fatty acids and
conjugated linoleic fatty acids. The present paper considers the fatty acid composition in
animal-derived foods and how these can be manipulated to be more conducive for consumers’
health. The importance of recognising the effect of livestock production systems
on fat composition is also highlighted along with the fact that we may have to compromise
between intensive, high levels of production and this particular aspect of food quality.