Association of Milk C-Reactive Protein With Subclinical Mastitis in Dairy Buffaloes

Subclinical mastitis is the predominant form of mammary inflammation in dairy buffaloes and remains a diagnostic challenge under field conditions.

This study assessed milk C-reactive protein (CRP) concentrations in relation to somatic cell count (SCC) and microbiological findings in Anatolian and Italian Mediterranean buffaloes.

Milk samples were collected from 160 individual mammary lobes and classified as subclinical mastitis-positive or healthy based on combined cytological and bacteriological criteria. SCC was determined using an automated cell counter, microbiological examination was performed by conventional culture and identification methods, and milk CRP concentrations were quantified by a sandwich ELISA.

SCC was significantly higher in subclinical mastitis-affected mammary lobes than in healthy controls in both breeds (p < 0.001). Mean SCC values were 1616.05 ± 167.04 ×10³ cells/mL and 1245.98 ± 82.90 ×10³ cells/mL in subclinical mastitis samples from Anatolian Mediterranean and Italian Mediterranean buffaloes, respectively, whereas corresponding control values were 285.48 ± 19.96 ×10³ cells/mL and 254.45 ± 21.44 ×10³ cells/mL (p < 0.001). Bacterial growth was detected only in samples classified as subclinical mastitis, with Staphylococcus aureus identified as the most frequent isolate. Mean milk CRP concentrations were significantly higher in subclinical mastitis samples compared with controls, with values of 196.26 ± 3.44 ng/mL and 205.45 ± 5.89 ng/mL in subclinical mastitis samples from Anatolian Mediterranean and Italian Mediterranean buffaloes, respectively, versus 162.16 ± 4.95 ng/mL and 158.22 ± 3.32 ng/mL in control samples (p < 0.001). Breed did not influence milk CRP concentrations within the same mastitis status.

These results indicate that milk CRP reflects mammary inflammatory activity and provides information complementary to SCC in the evaluation of subclinical mastitis in dairy buffaloes.