Abstract

The aim of this study was to evaluate the influence of seasonal factors and ewe age on mammary gland health and milk composition. Monitoring was conducted on a dairy flock of 200 Lacaune and East Friesian ewes located in central Slovakia. To evaluate the occurrence and etiology of mastitis, udder examinations and milk sampling for pathogen detection were performed three times during the grazing season: at the beginning, middle, and end. To compare milk production and composition in relation to age, 32 healthy ewes were selected during the same periods and divided into four groups based on their lactation number: 1st, 2nd, 3rd, and ≥ 4th lactation. The results showed that the prevalence of mastitis in the flock ranged from 7.7 to 11.0%, with subclinical forms at 4.5–8.5% and clinical forms at 2.0–5.0%. Regarding milk quality, ewes in the 2nd and 3rd lactations proved to be the most suitable, achieving the most stable and highest fat and protein content. Somatic cell count (SCC) increased with age and was more pronounced in ewes in their ≥ 4th lactation, where SCC reached 1,179 x 10³. From a practical standpoint, it is most efficient for breeders to utilize ewes up to their third lactation, as they achieve peak productivity and an optimal SCC level. These findings can serve as a basis for optimizing herd management, planning flock replacement, and improving the overall quality of milk intended for further processing.

Keywords

ewes, breeding system, grazing, mastitis, lactation, milk quality