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

Abstract

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.

Effects of Intensive and Semi-Intensive Production on Sheep Milk Chemical Composition, Physicochemical Characteristics, Fatty Acid Profile, and Nutritional Indices

“…Gonzalo [ 32 ] proposed a somatic cell count lower than 500,000 (5.70 log10 cells/mL) for good-quality milk, whereas the somatic cell count for healthy sheep mammary gland should not exceed 250,000 cells/mL (5.39 log10 cells/mL). Lianou et al [ 16 ] also reported no differences in the somatic cell count in bulk tank milk collected from farms using the intensive or the semi-intensive production system. In the previous study, the somatic cell count expressed as geometric mean was higher in the milk from intensive farms than in that from semi-intensive farms (5.45 × 10 5 vs. 4.50 × 10 5 cells/mL, respectively).…”

“…According to the same author, the distribution of farms according to the farming system is 5% nomadic, 50% semi-extensive, 30% semi-intensive, and 15% home-fed. In the recent countrywide study of Lianou et al [ 16 ] on milk hygiene from sheep flocks, the distribution of farms according to the production system was as follows: extensive 7%, semi-extensive 46%, semi-intensive 33%, and intensive 13%. As seen, the application of extensive and semi-extensive systems is declining, whereas the application of the semi-intensive system is increasing, and the application of the intensive system remains constant.…”

Antibiotic Resistance of Staphylococci from Bulk-Tank Milk of Sheep Flocks: Prevalence, Patterns, Association with Biofilm Formation, Effects on Milk Quality, and Risk Factors

“…Staphylococci are the most frequently recovered bacteria from the milk of sheep flocks [3,4]. Previous studies that examined staphylococcal isolates from bulk-tank milk of sheep farms mostly studied resistance to methicillin, with contrasting results: for example, in Italy, Macori et al [5] reported that 53% of 51 S. aureus recovered from the milk of six sheep farms showed resistance to methicillin, whilst Giacinti et al [6] reported that the prevalence of methicillin-resistant S. aureus among 286 sheep farms was only 0.7%.…”

Association of Staphylococcal Populations on Teatcups of Milking Parlours with Vaccination against Staphylococcal Mastitis in Sheep and Goat Farms

“…The great majority (87%) of staphylococci included biofilm-forming isolates. Specifically for sheep farms, this proportion (89%) was higher than among staphylococci that were recovered from the bulk-tank milk of the same sheep farms (72%) [8]. Biofilm-formation by these isolates had helped them to attach on the teatcups and, thus, survive cleaning.…”

“…In total, 255 dairy sheep flocks and 66 dairy goat herds in the 13 administrative regions of Greece were included into the study and visited for a collection of samples and information. Veterinarians that were active in small ruminant health management around Greece were contacted by telephone and asked whether they wished to collaborate in the investigation [4,8]; in total, 46 veterinarians collaborated in this work. The flocks were selected by the collaborating veterinarians on a convenience basis (willingness of farmers to accept a visit by University personnel for an interview and sample collection).…”