Antifungal Effect of Different Iodine Concentrations Against Aspergillus Species Isolated from Dairy Cow Teat Skin
| Author | Affiliation | |
|---|---|---|
| Date | Start Page | End Page |
|---|---|---|
2026-10-25 | 67 | 67 |
Iodine is a rapidly acting antiseptic with bactericidal, fungicidal, sporicidal properties (McDonnell and Russell, 1999). Iodine-based teat dips are widely used in dairy farms for teat disinfection (Ruegg, 2017). Fungi have been associated with subclinical and clinical mastitis in dairy cattle (Mahendra Pal, 2022). Therefore, evaluation of iodine-based teat disinfectants against fungal species isolated from teat skin is important for improving udder hygiene and mastitis prevention.
The aim of this study was to evaluate the antifungal activity of different iodine concentrations against Aspergillus species isolated from dairy cow teat skin.
Aspergillus spp. were isolated from teat skin samples using direct plating and washing–dilution methods on Sabouraud Dextrose Agar supplemented with chloramphenicol. Pure cultures were identified according to cultural and morphological characteristics using light microscopy. Antifungal activity was evaluated using the disk diffusion method. 1 mL fungal suspension (3 × 10^8 CFU mL) was inoculated onto Sabouraud Dextrose Agar. Iodine concentrations of 0.15%, 0.25%, 0.50%, and 0.75% (w/w iodine) were tested. Plates were incubated at 25 ± 1°C for 72–96 h, and antifungal activity was assessed by measuring fungal growth inhibition zones (mm).
Antifungal activity varied depending on iodine concentration and fungal species susceptibility. The strongest antifungal effect was observed at 0.50% iodine concentration. The highest susceptibility was detected in Aspergillus candidus (19.58 mm), followed by A. oryzae (11.0 mm), A. flavus (10.42 mm), and A. ochraceus (9.17 mm). A. niger showed the lowest sensitivity (5.58 mm). Lower iodine concentrations demonstrated weaker and species-dependent activity, while increasing iodine concentration to 0.75% did not improve antifungal efficacy.The results indicate that iodine-based teat disinfectants possess antifungal activity against environmental Aspergillus species isolated from teat skin. The 0.50% iodine concentration showed the highest inhibitory effect and may contribute to improved teat hygiene and reduced fungal contamination in dairy farms.