Comparison of thermography and MSAA-3 concentration measurement in the diagnosis of subclinical mastitis in cows

Mastitis is an inflammation of the mammary gland caused by bacterial, viral, fungal, or nonspecific agents. Mastitis is classified into two categories as subclinical and clinical mastitis, depending on the changes it causes in the mammary tissue and milk. Since subclinical mastitis usually does not show distinct symptoms, its early diagnosis is difficult. In this study, the effectiveness of infrared thermography and measurement of milk serum amyloid A-3 (MSAA-3) levels in the diagnosis of subclinical mastitis in cows was compared. Thermography is a non-invasive technique that visualizes the temperature distribution on the skin surface and can detect regional inflammation in the mammary tissue. MSAA-3 is an acute phase protein synthesized by mammary epithelial cells, found in milk, and increases during the inflammatory process. Following clinical examination and the California Mastitis Test (CMT), milk samples were collected from CMT-positive quarters for somatic cell count (SCC) and bacteriological culture. Subclinical mastitic quarters were randomly divided into three groups: Group I (Thermography, n=30), Group II (Thermography + MSAA-3, n=30), and Group III (MSAA-3, n=30). Thermographic imaging was performed under constant conditions, and MSAA-3 levels were analyzed using the ELISA method. A strong correlation was found between CMT and SCC (r = 0.826; p < 0.01), and moderate significant correlations were detected between CMT and MSAA-3 (r = 0.317; p < 0.05) and between SCC and MSAA-3 (r = 0.368; p < 0.05). In samples with bacterial growth, SCC, CMT, surface temperature, and MSAA-3 levels were found to be significantly higher. The findings indicate that thermography is a reliable and practical method for the early diagnosis of subclinical mastitis and that its combined use with MSAA-3 increases diagnostic accuracy