Table 1 Sampling details (sample type, quantity, and sampling method)

Feed and forage

 Grass from fresh pastures

250 g

Sterilized samples collection bag (13 × 19 cm) (Deltalab, Barcelona, Spain)

 Commercial feed

500 g

 Straw obtained from own fields^a

150 g

 Homemade feed (blend of grass, corn, beet blend)^a

500 g

Teat skin surface

30 swabs

(1 swab/10–15 sheep)

Sterile gauze swabs (7.5 cm × 7.5 cm) (Medrull, Dortmund, Deutschland) moistened in 0.9% (w/v) NaCl sterile solution (Scharlab, Barcelona, Spain) and deposited in individual sterile 100 mL bottles (Deltalab, Barcelona, Spain)

Raw milk

1 L

Sterilized 1 L borosilicate glass bottles (Deltalab, Barcelona, Spain)

Dairy surfaces

 Food contact surfaces (e.g., equipment, materials, trays, shelves)

30 swabs

Sterile gauze swabs (7.5 cm × 7.5 cm) (Medrull, Dortmund, Deutschland) moistened in 0.9% (w/v) NaCl sterile solution (Scharlab, Barcelona, Spain) and deposited in individual sterile 100 mL bottles (Deltalab, Barcelona, Spain)

 Non-food contact surfaces (e.g., floors, walls)

30 swabs

Cheese-making ingredients

 Rennet

50 g

Individual sterile 100 mL bottles (Deltalab, Barcelona, Spain)

 Brine

1 L

Sterilized 1 L borosilicate glass bottles (Deltalab, Barcelona, Spain)

Dairy samples

 Whey

1 L

Sterilized 1 L borosilicate glass bottles (Deltalab, Barcelona, Spain)

 60-day-ripened cheese (1–1.5 kg)

2 units

Sterilized samples collection bag (19 × 38 cm) (Deltalab, Barcelona, Spain)