Comparing bacterial counts on bare hands with gloved hands during milking

Milking parlor hygiene has been propagated by many veterinarians, extension specialists, and researchers. Research has shown that producers that work clean and precise have in general lower incidence rates of clinical mastitis and lower bulk milk somatic cell counts. Part of the recommended milking procedures is wearing milkers gloves during milking. Some studies have shown that similar strains of mastitis pathogens can be found in milk samples, udder skin, and on milkers' hands, suggesting that mastitis pathogens can be transmitted from cow to cow via hands. The goal of the present study was to conduct a quantitative comparison of bacterial counts on bare hands, disinfected hands, gloves, and disinfected gloves. The glove-juice method (50 ml 0.9% NaCl) was used to quantify bacterial presence on 27 milkers' hands. The milkers were asked, after milking a full parlor of cows (8 to 36 stalls), to rinse off his hands and wipe them dry using a cloth or paper towel before the bare or gloved hand was sampled. After sampling the bare or gloved hand, the milker was asked to disinfect his hand or glove with alcohol-impregnated udder wipes (TeaterClean®) before sampling the disinfected hand or glove again. Disinfecting bare hands reduced bacterial load with 85%. Wearing gloves and disinfected gloves reduced bacterial loads compared with bare hands with 75% and 98%, respectively. This method only evaluated the total bacterial load on milkers' hands. The vast majority of the isolated bacteria are most likely harmless. This study showed, however, that using gloves during milking will reduce the exposure of teats to bacteria through milkers' hands.