1. Maize and milk quality Gillian Butler Nafferton Ecological Farming Group Newcastle University Research supported by EU funding

2. Milk fat & dietary guidelines Milk dominated by saturated fatty acids but also source of essential unsaturated fatty acids - both omega-3 and omega-6 (n-3 & n- 6) Dairy feeding determines milk fat composition European and WHO guidelines: ‘western diets’ oversupply n-6 but inadequate for n-3 Ideally ~ 2-5 x n-6 to 1 x n-3 Excess n-6 compromises synthesis of long chain n-3 PUFA ie DHA and EPA

3. European study Farm survey in: UK, Sweden, Denmark & Italy 5 systems in each country, including 2 organic or low input (1/4 in Sweden) Bulk milk and management information (including feeding details) collected 5 times throughout the year Fatty acid & fat soluble antioxidant profiles determined

5. Fresh forage Grass silage Maize silage Concentrate omega-6 omega-3 CLA9 Effect of diet on milk composition (European study) Concentrations of omega-6 PUFA in milk associated with maize silage, hay and concentrate feeding