Infectious bovine keratoconjunctivitis, commonly known as pinkeye, is a highly contagious bacterial infection of cattle eyes caused by Moraxella bovis. It causes inflammation of the cornea and conjunctiva, potentially leading to blindness. The disease is most common in the summer and spreads rapidly. Clinical signs progress from tearing and sensitivity to light to cloudiness and ulcers of the cornea in four stages. Diagnosis is based on symptoms, and treatment focuses on antibiotics and minimizing sunlight exposure to prevent further spread. Proper management practices can help control the disease.

1. Infectious Bovine
Keratoconjunctivitis
Submitted by: Dr. Kanwarpal Singh Dhillon
M.V.Sc (Medicine)

2.  Pink eye or infectious bovine keratoconjunctivitis (IBK) is the
most common & costly ocular disease of cattle.
 It is an inflammatory bacterial infection of the eye that can cause
permanent blindness in severe cases.
 It is a highly contagious disease, causing inflammation of the
cornea (the clear outer layer) and conjunctiva (the pink membrane
lining the eyelids) of the eye.
 IBK is characterized by blepharospasm, conjunctivitis, lacrimation
and varying degrees of corneal opacity and ulceration.
 The disease usually is acute and tends to spread rapidly
 The incidence of pinkeye increases in spring, peaks in the summer,
and decreases in the fall/Autumn.
Introduction

3. Etiology
 The primary infectious agent for pinkeye is the bacterium
Moraxella bovis.
 The bacteria produce a toxin which attacks the surface of the
eye (cornea) and conjuctiva, causing inflammation and
ulceration.
 This bacterium is found in the eyes of many recovered and
apparently normal cattle.

4. Predisposing Factors
 Infection with IBK or other microbes may increase the
severity of infection with M bovis.
 Plant pollens, face flies, ultraviolet radiations, tall grass, dry
and dusty environmental conditions and transportation
stress.
 Flies (Musca spp.) can also serve as mechanical vectors for
M. bovis.
 Eye irritation.
 Calves are more likely to develop the disease than adult
cattle, as adult cattle appear to develop protective
antibodies on the surface of the eye.
 Bull calves have a higher incidence of disease than heifer
calves.

5. Clinical Signs
Stage I
Cattle have excessive tearing and
increased sensitivity to light.
They will blink frequently and there
is redness along the eyelids.
Cattle will often seek shade, which
will decrease their grazing time.
Pain associated with pinkeye also
decreases their feed intake.
 Stage I will progress to a small ulcer in the centre of the
cornea which appears as a small white spot.
 The cornea develops a slightly cloudy grey appearance due to
inflammation.
 One or both eyes may be affected.
Stage I

6. Stage II
 The clinical signs described in
Stage I continue, but the ulcer
spreads across the cornea.
 As more inflammation occurs,
the cornea becomes increasingly
cloudy.
 At this point, some of the dark
color of the iris can still be seen.
 The blood vessels make the
cornea appear pink, which is
how the disease received its
name.
Stage II

7. Stage III
 The ulcer covers most of
the cornea and the
inflammation continues to
spread into the inner parts
of the eye.
 When this occurs, the
inside of the eye fills with
fibrin, which is a pus-like
substance that gives the
eye a yellow appearance
versus the typical brown
appearance. Stage III

8. Stage IV
 The ulcer extends completely
through the cornea, and the
iris may protrude through
the ulcer. The iris will become
stuck in the cornea even after
healing.
 This may lead to glaucoma or
persistent swelling of the eye.
This eye will be partially or
completely blind.
 The eye may go on to completely rupture, and will develop a
shrunken appearance or enlarge if glaucoma (increased eye
pressure) is present.
 This eye will be permanently blind.
Stage IV

9. Early clinical signs are photophobia, blepharospasm and
epiphora later the ocular discharge may become mucopurulent.

10. Severe corneal edema, corneal neovascularization and epiphora

11. Conjunctivitis, with or without varying degrees of keratitis,
is usually present along with epiphora

12. Lesions
In cattle, one or more small ulcers typically occur near the
center of the cornea.
Lesions may regress in the early stages or may continue to
progress

13. Diagnosis
 Presumptive diagnosis is based on ocular signs and
concurrent systemic disease.
 Microbial culture is important for confirmatory
diagnosis.
 It is important to distinguish that the lesions are not
due to some other cause like some systemic disease
or foreign bodies or parasites.

14. Differential Diagnosis
 Traumatic conjunctivitis – evidence of phyical injury or presence of
foreign material in the eye.
 Pasteurella multocida (capsular type A) – isolated from the eyes;
outbreaks of severe keratitis with loss of corneal stroma.
 Mycoplasma bovis – isolated from the eyes; outbreaks characterized
by severe conjunctivitis, corneal opacity, ulceration, & swelling of
eyelids.
 Other diseases – Listeria monocytogenes iritis , Infectious bovine
rhinotracheitis, Bovine malignant catarrh & Chalmydial
keratoconjuctivitis & Thelaziasis

15. Treatment
IBK is frequently a self-limiting disease.
Topical therapy:
 Early, acute cases respond to Rx with ophthalmic
ointments & solutions containing Ab.
 Administration of Benzathine cloxacillin 375mg (oil-based)
is found to be effective. Two doses, 72 hrs. apart, are
recommended.
 Effective antibiotics for topical ophthalmic use include
triple antibiotic, Gentamicin, and a combination
Oxytetracycline / Polymyxin B ointment.

16. Subconjuctival therapy:
 Procaine penicillin (3-6x105
IU) is given through the skin
of upper eyelid or under the bulbar conjunctiva
Parental therapy:
 Sulfadimidine @100mg/kg BW.
 Long-acting oxytetracycline (2 injections @20 mg/kg,
IM or SC, at a 48- to 72-hr interval) alone or with oral
administration of OTT @2g/250kg BW for 10 days.
Ancillary therapy:
 Animal should be placed in dark shelter out of direct
sunlight.
 If housing is not possible, eye flap patches are glued on
above the eye & can be flipped up for the medication.

17.  Animals with substantial uveitis secondary to
Keratoconjunctivitis that is particularly painful may
benefit from topical ophthalmic application of 1%
atropine ointment 1–3 times daily.
 Systemic NSAID may be used to provide relief from
secondary uveitis.

20. Prevention and control
 Good management practices
 Separation of infected animals
 Ultraviolet radiation from sunlight may enhance the disease therefore
affected animals should be provided with shade.
 Reduce the incidence of flies and subsequent spreading of bacteria with
the application of pour-on treatments.
 Dust bags or insecticide-impregnated ear tags can be used to reduce the
number of face flies

21. References:
 VETERINARY MEDICINE A textbook of the diseases of cattle, horses, sheep, pigs
and goats by O. M. Radostits, C.C.Gay, K. W. Hinchcliff, P. D.
 Rebhun’s Diseases of dairy cattle by Thomas J. Divers & Simon F. Peek
THANKS……..