The WPDiarrhoea-Panel-4 comprises a series of species-specific targeted reagents designed to evaluate the expression of four virulence factors (fedA, faeG, eae and toxA from Escherichia coli) by using qPCR. Post weaning diarrhoea is an important enteric disease that usually occurs shortly after weaning and is characterized by watery diarrhoea, dehydration, loss of body weight and death of infected pigs. This diarrhoea is responsible for important economic losses due to mortality, morbidity, decreased growth rate and cost of medication. Escherichia coli is one of the most important causes of the increasing worldwide outbreaks of post weaning diarrhoea, causing sudden death or severe diarrhoea. The PCR identification of virulence factors of E. coli from faecal samples is normally used for diagnosis of pathogenic isolates. WPDiarrhoea-Panel-4 allows evaluation of the expression of some of this virulence factors as toxA, coding for the heat-labile enterotoxin (LT); eae, coding for the intimine; fedA, coding for the F18 fimbriae and faeG, coding for the F4 fimbriae.