August 27, 2009
It shows up every year and to the unlucky cattle
that contract it, Infectious Bovine Keratoconjunctivitis (IBK), more
commonly called pinkeye, is incredibly painful and if left untreated,
can lead to loss of the eye, a Kansas State University veterinarian
"Pinkeye is usually caused by the bacteria Moraxella bovis," said K-
State Research and Extension veterinarian Larry Hollis. "However,
we´ve found that in many cases - especially the extremely difficult
cases - another bacteria, either Branhamella ovis or Mycoplasma
bovoculi, is also present."
The disease is spread by flies, said Hollis, which means that good
fly control around cattle production areas should always be a
In its early stages, pinkeye is usually easier to treat, he said. The
disease can accelerate rapidly, however, and if not treated
aggressively can lead to damage to the eye or complete loss of the
"It is painful as all get-out," said Hollis, who added that cattle
with an active case of pinkeye or those with permanent damage are
discounted at sale time. "Watch for animals that are producing an
unusual amount of tears (discharge) that show up on the face," he
said, adding that "there will always be a carrier animal in the
vicinity - either in your herd or one down the road."
Those who suspect pinkeye should look into the eye closely for any
ulceration on the cornea. In extreme cases the cornea will appear
white because of pus buildup inside the eye.
Cattle with pinkeye are extremely sensitive to light - even on a
"If you´re got a few cattle that are hanging back in the shade while
the rest go out to graze, even on days with cloud cover, you very
well may have a pinkeye problem," the veterinarian said.
Pinkeye is often at its worst in late summer and early fall because
the fly population has had time to build through the summer, he
Also, pasture grasses are tall this time of year and can irritate
cattle´s eyes as they graze. Once an animal´s eye starts tearing in
response to irritants, flies are attracted to the discharge, some of
which may be carrying the Moraxella bovis bacteria.
"Tears are like a magnet for flies," Hollis said.
Oxytetracycline is often effective in treating individual animals
with pinkeye, he added, but he encourages producers to call their
veterinarian about the best treatment options.