Detection of Coxiella burnetii in the mammary gland of a dairy goat

AbstractThe zoonotic bacteriumCoxiella (C.) burnetii can be excreted by infected goats through birth products and milk. The detection ofC. burnetii DNA in the mammary gland tissue of infected dairy goats and intermittent milk shedders has been reported, but confirmation ofC. burnetii bacteria in the udder remained pending. The pathogen caused abortions in a 152-head dairy goat herd, resulting in the vaccination againstC. burnetii of the entire herd with annual boosters. To monitor theC. burnetii shedding at herd level, monthly bulk tank milk (BTM) samples were analyzed using PCR (IS1111). Despite vaccination,C. burnetii DNA was detected in BTM samples within the first 16 months of the study. Therefore, individual milk samples were tested on four different occasions several months apart to identify potential intermittent milk shedders. Only one goat (#67455) tested positive three times. This goat was necropsied to investigate the presence ofC. burnetii in the udder and other organs. PCR detectedC. burnetii DNA solely in both mammary glands and the left teat cistern. Immunohistological examination identifiedC. burnetii antigen in mammary gland tissue, confirmed by the detection ofC. burnetii bacteria in the mammary epithelial cells using fluorescence in situ hybridization. The removal of goat #67455 led to negative BTM samples until the end of the study. The findings demonstrate the occurrence ofC. burnetii in the mammary gland of a naturally infected and vaccinated goat. The p...
Source: Veterinary Research Communications - Category: Veterinary Research Source Type: research