Table 4. Hotelling’s T-test P-values (above diagonal) and Mahalanobis’s distances (below diagonal) between diets, calculated on the expression of a set of 8 genes selected by the stepwise discriminant analysis.

	D1	D2	D3	D4
D1	-	0.002	< .0001	0.003
D2	3.84	-	0.13	0.001
D3	7.30	1.68	-	0.0001
D4	3.50	4.51	5.42	-

D1 = standard diet for growing-finishing pigs; D2 = standard diet supplemented with linseed (source of n-3 PUFA); D3 = standard diet supplemented with linseed, vitamin E and selenium; D4 = standard diet supplemented with linseed and plant extracts from grape-skin and oregano as a source of polyphenols.