The prevalence of environmental and contagious bovine mastitis, risk factors associated with feed supplements, farm and milking hygiene in Albania dairy cattle

Abstract

Despite the existence of traditional mastitis control programs, subclinical mastitis remains the most prevalent infectious disease affecting dairy cattle. In developed countries, national mastitis councils are typically established to address udder health and implement control strategies. In contrast, Albania lacks both a formal mastitis control program and the organizational framework needed to establish such a council, despite the recognized burden of subclinical mastitis in dairy herds.

This study aimed to (i) assess the prevalence of subclinical mastitis, (ii) identify the causative bacterial pathogens, (iii) determine the antimicrobial susceptibility of major isolates, and (iv) evaluate key risk factors associated with disease occurrence. A cross-sectional survey was conducted across 35 small to medium-sized dairy farms using the California Mastitis Test (CMT) for screening. Milk and feed samples, along with farm-level metadata, were collected and analyzed for bacteriological profiles, antimicrobial resistance patterns, and mineral content.

The overall prevalence of subclinical mastitis at the cow level was 59.5% (95% CI: 52.8–65.9%), while herd-level prevalence reached 97.1% (95% CI: 85.5–99.5%), with 34 out of 35 farms testing positive. Bacteriological analysis revealed both contagious and environmental pathogens, with Staphylococcus aureus being the most frequently isolated, followed by Pseudomonas aeruginosa, Escherichia coli, and Enterobacter spp. Antimicrobial susceptibility testing showed widespread multidrug resistance among isolates; notably, enrofloxacin was the only antibiotic effective against more than half (59.6%) of the isolates.Significant associations were found between subclinical mastitis and poor udder hygiene (P = 0.001), as well as deficiencies in dietary supplementation. Positive correlations were observed with zinc (R² = 0.136–0.197; P = 0.041), selenium (R² = 0.33; P = 0.001), vitamin A (R² = 0.35; P = 0.001), and vitamin E (R² = 0.31; P = 0.001) intake.

The high prevalence of subclinical mastitis and the emergence of antimicrobial resistance highlight the need for urgent action. The lack of awareness among farmers and the absence of a structured control program suggest that national strategies, including education, coordinated interventions, and possibly the establishment of a mastitis council, are essential to improve udder health in Albanian dairy farms.