Analytical units with 25 g of chicken skin and tomatoes were weighed in sterile plastic bags, diluted with 225 mL of BPW, and homogenized for 1 min in a stomacher. Decimal dilutions were carried out with BPW for all samples (swabs, tomatoes and skin) and plated on BS agar supplemented with 100 μg of nalidixic acid per mL of medium. Plates were incubated at 35 °C/24 h.