The aim of this study is to investigate the prevalence of mastitis in different breed cows raised on small-scale farms, bacterial growth rates in milk samples obtained from these farms, and the factors affecting the milk component. In this study, 211 cows of different breeds (Simmental, Montofon, and Holstein) aged between 2 and 8, primar and multiparous were used. According to the results of the California Mastitis Test (CMT), 150 cows (71.09%) have a positive reaction, while 61 cows (28.91%) have a negative (-) reaction. Of the 844 quarters of 211 cows used in the study, 16 quarters were excluded from the study because they were blind. Of the 828 quarters included in the study, 438 (52.90%) quarters were found to be CMT (-) and 390 (47.10%) quarters were found to be CMT positive. The bacterial growth rate in CMT positive quarters was 92.11%. Most Staphylococcus aureus (S. aureus) was detected (30.99%). The lowest fat ratio (4.48% ± 0.12%) was seen in CMT (-). Protein (3.51 ± 0.02%), lactose (5.28 ± 0.04%), solid-non-fad (SNF) (9.68 ± 0.07), and mineral matter (0.75% ± 0.01%) rates were the lowest in the CMT (+++) group. Density (1,033.22 ± 0.19 kg/m3) was found in the highest CMT (-) group, while electrical conductivity (4.69 ± 0.01 mS/cm) was highest in the CMT (+++) group. The lowest fat rate (3.86% ± 0.27) is observed in the 3rd lactation. Lactose (5.52% ± 0.04), SNF (10.08% ± 0.07), and protein (3.66% ± 0.03) ratios were found to be higher in cows in the 3rd lactation. Moreover, the milk electrical conductivity (4.40 ± 0.03 mS/cm) of the cows in the 3rd lactation had the lowest value, while the density (1,034.02 ± 0.44 kg/m3) was found to be high. While somatic cell count (SCC) was found to be high in milk obtained from rear-heavy udder form (573.84 ± 63.11 cells⁄ml), it was understood that there was no statistical difference in terms of milk composition except for lactose ratio. SCC was found to be low in milk obtained from quarters with cylindrical teat (383.02 ± 43.70 cell⁄ml) and flat teat end shape (370.79 ± 43.61 cell⁄ml). Bacterial growth was low in trough-shaped udder form (15.2%), while bacterial growth rates were found to be high in cows with pendulous (27.6%) and rear-heavy udders (29.9%). In conclusion, it was seen that subclinical mastitis was common and this disease was mostly caused by S. aureus. In order to reduce mastitis, preventive measures should be taken, especially against S. aureus. It was concluded that the use of cows with trough-shaped udder form and cylindrical teats in breeding will contribute to the reduction of mastitis.