Extensive Countrywide Field Investigation of Somatic Cell Counts and Total Bacterial Counts in Bulk-Tank Raw Milk in Sheep Flocks in Greece

• Main Authors: Daphne T. Lianou, Charalambia K. Michael, Natalia G.C. Vasileiou, Efthymia Petinaki, Peter J. Cripps, Katerina Tsilipounidaki, Angeliki I. Katsafadou, Antonis P. Politis, Nikos G. Kordalis, Katerina S. Ioannidi, Dimitris A. Gougoulis, Constantina Trikalinou, Denise C. Orfanou, Ilektra A. Fragkou, Elisavet Angelidou, Eleni I. Katsarou, Athina Tzora, Marzia Albenzio, Vasia S. Mavrogianni, Mariangela Caroprese, George C. Fthenakis
• Format: Article
• Language: English
• Published: MDPI AG 2021-01-01
• Series: Foods
• Subjects: bulk-tank; goat; mastitis; protein content; raw milk; sheep
• Online Access: https://www.mdpi.com/2304-8158/10/2/268

Objectives were to investigate somatic cell counts (SCC) and total bacterial counts (TBC) in the raw bulk-tank milk of sheep flocks in Greece, to study factors potentially influencing increased SCC and TBC in the bulk-tank milk of sheep and to evaluate possible associations of SCC and TBC with milk content. Throughout Greece, 325 dairy sheep flocks were visited for collection of milk sampling for somatic cell counting, microbiological examination and composition measurement. Geometric mean SCC were 0.488 × 10⁶ cells mL⁻¹; geometric mean TBC were 398×10³ cfu mL⁻¹; 228 staphylococcal isolates were recovered form 206 flocks (63.4%). Multivariable analyses revealed annual incidence risk of clinical mastitis, age of the farmer and month into lactation period (among 53 variables) to be significant for SCC > 1.0 × 10⁶ cells mL⁻¹ and month into lactation period at sampling and availability of mechanical ventilators (among 58 variables) to be significant for TBC > 1500 × 10³ cfu mL⁻¹. Negative correlation of SCC with fat, total protein and lactose and positive correlation of SCC with added water were found. With SCC > 1.0 × 10⁶ cells mL⁻¹, significant reduction of protein content (2%) was observed, whilst in flocks with SCC > 1.5 × 10⁶ cells mL⁻¹, significantly lower annual milk production per ewe (42.9%) was recorded.