Table 1.

The experimental design of a study aiming to scrutinise the effect of different feed related prophylactic measures in pigs exposed to three pathogenic serotypes of E. coli via the environment. The pigs were weaned on living day 35.

	Exposed to		Feed
Group	Pathogenic E. coli	Non-pathogenic E. coli	Structure	Heat processed (75°C for 20 sek)	Protein (%)	ZnO (2500 ppm)	Lactose
A	-	-	Pelletedc	Yes	15.5	-	-
B	Yesa	-	Pelletedc	Yes	15.5	Yes	-
C	Yesa	-	Meald	-	14.5	-	Yes
D	Yesa	-	Pelletedc	Yes	15.5	-	-
E	Yes	Yesb	Pelletedc	Yes	15.5	-	-

^a) E. coli O147; K89, STb at the day of weaning;

E. coli O141; K85, STb, VT2 and E. coli O149; K91, K88, STa, STb, LT three days post weaning

^b) A mixture of 10⁶ CFU of each of 60 defined non pathogenic strains of E. coli given per os.

^c) Startgris Fiber, Lantmännen, Svalöv, Sweden

^d) Meal feed with lactose, dietary fibres and char cole (Nibble, Tillberga, Sweden)