Manipulating dietary PUFA in animal feed: implications for human health

Abstract

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. PUFA: Animal feeding: Eggs: Milk: BeefDietary guidance to reduce total fat intakes might decrease harmful SFA consumption if implemented successfully; however, it will also reduce the supply of beneficial unsaturated fatty acids (FA), including n-3 fatty acids, currently considered inadequate. A more prudent approach might be to adjust the relative proportion of the various FA in our food aiming to increase PUFA intake and reduce SFA. On average in the UK between 53 and 57 % of our SFA intake comes from animalderived foods; dairy, meat and eggs, yet their consumption is estimated to provide only 30 % of PUFA intake (1) . This fact, along with the known variation in FA profiles in animal-derived foods, makes them obvious candidates to investigate the scope to manipulate fat composition as a means of improving the balance of FA in our diet.The benefits of PUFA over SFA are well recognised and the Food and Agriculture Organization paper 91 on fats and FA in human nutrition (2) and the European Food Standards Agency (3) provide relatively recent consensus on acceptable guidelines for fat intake and composition, although identifying knowledge gaps and the need for further research.

Linoleic acid and the pathogenesis of obesity

“…During almost all of the nutrition transitions worldwide (with South Korea being an exception [19]) an increase in energy from plant based fats has occurred, resulting in an increase in dietary LA [13]. Furthermore, due to changes in animal feed practices resulting in an increase in grain feeding, animal products now also have an increased LA content than their traditional counterparts [20,21]. A key follow-on from these nutrition transitions has been an increase in obesity rates and the prevalence of non-communicable diseases such as CVD and type 2 diabetes mellitus (T2DM) [22].…”

Animal nutrition in a 360-degree view and a framework for future R&D work: towards sustainable livestock production

“…Butler 2014;Vazirigohar et al 2014) present opportunities to improve final product quality including increases in conjugated linoleic acid, omega-3 fatty acids, minerals in animal products, and product shelf life through manipulation of animal feeding. Many of these changes elicit positive effects on human health (Ip et al 1991;Belury 2002;Bauman et al 2006).…”

Improving meat quality through cattle feed enriched with mate extract: an integrated approach of the metabolic profile and redox chemistry of meat

“…44 On the other hand, several studies have demonstrated the potential benefits of n-3 PUFA supplementation for health. 29,[43][44][45] Amino acids, peptides, nucleotides and sugars correspond to meat polar metabolites and, many of them are water-soluble precursors of meat flavour. [51][52][53][54] The presence of nucleotides in meat is important not only for the flavour but also because some nucleotides are considered biomarkers for relevant metabolic pathways.…”

“…27,29,30,44,47,80,102 Together with the increasing demand for high quality meat, there is an increasing public concern to propose a more humane production of meat, and for alternatives to prevent environmental impact due to intensive livestock farming. Diet manipulation has the advantages to naturally induce changes in the meat composition avoiding the use of antibiotics and hormones.…”

“…An increase in content of plant rich in bioactive compounds like antioxidants for ruminant feed may, however, affect the microflora of the rumen subsequently affecting meat composition and quality. 24,29,30 Mate is generally recognized as safe (GRAS status) and is native to the South America region with the highest beef production and also with the highest beef consumption.…”