Fungal isolation from bovine milk samples in an Italian dairy farm: preliminary results

Aim of the study was to isolate yeasts from quarter milk samples of cows in one Italian dairy herd. A total of 304 quarters were classified as healthy (H) (negative CMT score, normal milk and no clinical changes of the udder), subclinical mastitis (SCM) (positive CMT score, normal milk and udder), clinical mastitis (CM) (positive CMT score, modified milk and udder). Milk samples were aseptically collected in a sterile tube, stored at 4–8°C, plated within 24 h onto malt extract agar added with biphenyl 0.1% and gentamicin 0.1%. Plates were incubated at 25°C and daily examined over a 21 day period. Yeasts’ identification was achieved on the basis of macro‐ and microscopic features of colonies and by means of a technique of carbohydrate assimilation using commercial galleries (ID32C). Yeasts prevalence was calculated. A Chi‐square test was applied for H and SCM+CM in relation to presence/absence of yeasts. Statistical significance was set at p < 0.05. The H quarters were 65.5%, the SCM 27% and the CM 7.5%. Yeasts were isolated in 5% of H, 2.3% of SCM and 0.7% of CM quarters. The prevalence of fungi was: Candida spp. 5.6% (Candida curvata, Candida famata, Candida rugosa, Candida catenulata, Candida guiilliermondii, Candida sphaerica), Rhodotorula sp. 2.6%, other yeasts 1%. Chi‐square test was not statistically significant. Our results confirmed that fungal species usually associated with mastitis are present also in normal milk.