INFECTIOUS BOVINE KERATOCONJUCTIVITIS

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INFECTIOUS BOVINE KERATOCONJUCTIVITIS

• JOSE R. CASTRO
• UT-CVM
• 2001

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IBK-Pink Eye

• International Ocular Disease
• Economic Impact
• a) Decreased Weight Gain
• b) Milk Discard
• c) Decreased Show Value
• d) Cost of Theraphy

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Etiology

• Moraxella Bovis
• Brannamella Ovis
• Mycoplasma bovoculi
• IBR
• Predispose an animal to IBK

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Moraxella Bovis

• Gram Negative Rod
• a) Rough Virulent, Piliate
• Pili Type I Maintain Infection by invading
  deeper tissues
• Pili Type Q Enhence the ability to adhere
  to Corneal Epithelium
• b) Smooth Avirulent, Non Piliate

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Epizoology

• 1.- Direct Contact
• 2.- Nasal and Ocular Discharges
• 3.- Vectors
• a) Face Fly ( Musca autumnalis)
• b) House Fly ( Musca domestica)
• c) Barn Fly ( Musca Stomoxyscalcitrans)
• Most Prevalent in late summer

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Pathophysiology
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Clinical Signs

• Phthisis Bulbi
• Buphthalmus
• Blepharospasm
• Purulent Discharge
• Conjunctivitis

• Vascularization
• Photophobia
• Corneal Edema
• Ephiphora
• Corneal Opacity

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Treatment

• Isolation of affected animals
• Deacreased UV Radiation (Shaded Shelters)
• Limited Flies (Eye Patches)
• Third Eyelid Flap
• Periocular Artificial Pigmentation???
  (Sprays,Dyes,Tattooing)
• Antimicrobial...

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Antimicrobial

• Lack of the Treatment
• a) Short tear half-life of topical antimicrobial
• b) Limited Ocular presence after parenterally
  administration...???

• Penicillin Aminoglycosides
• (Subconjuctival)
• Streptomycin
• Gentamycin
• Cephalosporin
• Nitrofurans
• Sulfanilomides

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Efficacy of Florfenicol

• Corneal ulcers healed by day 20
• - 98 Florfenicol IM
• - 93 Florfenicol SC
• 40 mg/Kg SC Single Dose
• 20 mg/Kg IM Double Dose, one day apart.
• (J Am Vet Med Assoc 2000 216 62-64)

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Options....

• Florfenicol
• No FDA Approved
• Alternative to Oxt.
• -Resistance
• -Anaplasmosis (Oxt. is restricted)

• Long-Acting Oxitetracycline
• IM / 2-Dose
• Conjuctival levels remain at 2 mg/ml for 72 hours
• FDA Approved

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Prevention

• Uppon recovery cattle show resistance to
  reinfection.
• Bacterins ???
• (Heards vaccinated with modified-live IBR virus
  have an increased risk for IBK. Vx during the
  winter)
• Management!!!

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Management

• Reduce Mechanical Irritation
• Tall grasses, Noxious Weeds, Shrubs should be
  cleared from pastures
• Modifying Bale Feeder ( Increased Head Space to
  15 inches)
• Irritation due to Face Fly...Ear Tag
• Limited Stress
• Phrophylactic Dose of Antib. to override the
  critical post-shipping stress period.