Background:

Cattle mastitis is a global sanitary and economic problem that affects human and animal health. Several microorganisms involved in its etiology, such as Mycoplasma bovis, make prevention and control more difficult.

Aim.

To deepen the bacterial etiology of cattle mastitis in Zamora-Chinchipe, Ecuador, where collected milk was observed to have Mollicutes.

Materials and methods:

A number of 247 milking cows were studied in 2015-2016 in herds from Zamora-Chinchipe province, selected in areas with adequate ecological characteristics. The California Mastitis Test (CMT) was run on milk samples from each cow whereas Polymerase Chain Reaction (PCR) was performed to detect Mollicutes, and a bacteriological diagnostic was made to identify other pathogens. A comparison of proportions analysis was conducted to analyze the results of Mollicute presence, and CMT in the cows per cantons, and between the pathogens identified in the Mollicute-positive cows. Chi-square helped evaluate the relation between the Mollicute diagnostic results and CMT, and the pathogens identified. Logistic regression was useful to compare the prevalence ratio (PR).

Results:

The frequency of subclinical mastitis was found at high levels (81.4%) through CMT, and a frequency of 33.2% of Mycoplasma spp.-positive cows. In the bacteriological diagnostic, Streptococcus spp. (27.2%) and Staphylococcus aureus (22.1%) showed the highest frequencies (P< 0.05). S. aureus was detected with the highest frequency in the Mycoplasma spp.-positive cows (43.8%; P<0.05).

Conclusions:

The high infection caused by Mycoplasma spp. and S. aureus was significant, due to their potential repercussion on the clinical-epidemiological behavior of bovine mastitis in the province.