Digital papillomatosis (hairy warts) was
diagnosed in a dairy herd with a high level
of lameness (20%). Warts ranged from
mild to moderate to severe, with severity
increasing with length of lactations. All
milking cows (100%) had at least mild
lesions. Cows with severe lesions were
more likely to be lame. Severity of lesions
had no influence on 305-day ME milk production,
days open, or somatic cell counts.
Cows in milk more than 150 days and lame
produced 3 kg less milk per day than cows
that were not lame. Almost all warts were
in the interdigital cleft near the heel of the
rear feet. A few cows had lesions in the
front of the interdigital cleft or on the front
feet. No viral particles were observed or
isolated. A new, Gram-negative, motile,
facultatively anaerobic, spiral-shaped bacteria
was isolated from one lesion. The
cellular fatty acid profile of this bacterium
had no match to any other known bacteria
in any of three computer databases examined.
Cows with severe lesions were assigned
randomly to one of four groups: Group 1:
surgical removal and autogenous vaccination;
Group 2: surgical removal only;
Group 3: autogenous vaccination only, and
Group 4: control. Neither surgical removal
nor autogenous vaccination had a significant
effect on wart severity, lameness, or
milk production when cows were
inspected 10 wk later. Contemporary
evaluation of 249 herdmates revealed a
substantial number of severely affected
cows naturally improved. Of 25 severely
affected herd contemporaries, only 8 were
severely affected 10 wk later. Evidently,
natural improvement of lesions is a common
phenomenon with “hairy warts. ”
