Short communication: Shedding of Mycoplasma bovis and antibody responses in cows recently diagnosed with clinical infection

摘要

ABSTRACTMycoplasma boviscan have significant consequences when introduced into immunologically naïve dairy herds. Subclinically infected carrier animals are the most common way thatM. bovisis introduced into herds. AlthoughM. bovisudder infections can be detected by milk sampling lactating animals before their introduction, currently, no definitive way of identifyingM. boviscarrier animals that are nonlactating (i.e., calves, heifers, dry cows, or bulls) is available. Understanding the prevalence ofM. bovisshedding from various body sites in clinically infected animals could inform strategies for the detection of subclinical infection in nonlactating stock. The mucosal surfaces of the nose, eye, and vagina of 16 cows with recent clinical mastitis caused byM. boviswere examined for the presence ofM. bovisshedding. Blood was collected for serological evaluation by a commercially available ELISA.Mycoplasma boviswas isolated from the vagina of only 3 (18.8%) of the cows and was not detected from the noses or eyes of any of the cows. Fifteen of the 16 (93.8%) cows were seropositive to the ELISA. With such low prevalence of detection ofM. bovisfrom the vagina and no detections from the noses or eyes of recently clinically infected animals, it is very likely that sampling these sites would be ineffective for detecting subclinical infection in cattle. Serology using the ELISA may have some use when screening animals for biosecurity risk assessment. However, more information regarding time to seroconversion, antibody longevity, and test diagnostic sensitivity and specificity are required to define the appropriate use of this ELISA for biosecurity purposes.