Bovine eye Flashcards
Wha topical local anaesthetic can be used in bovine eyes?
Amethocaine
Give differential diagnoses for blindness in farm animals
CCN
Vitamin A deficiency
Lead poisoning
Twin lamb disease (sheep)
What causes Bovine Iritis/uveitis or Silage Eye?
Listeriosis
Big bale silage in Winter
Silage Eye or Bovine Iritis is negative to fluorescein. How is it treated?
Atropine - mydriatic
Dexamethasone
+/- oxytetracycline
What ocular signs may BVD present with?
Microphthalmia
Cataracts
Retinal dysplasia or detachment
How many days into pregnant does BVD cause occular manifestations?
75-150d
What ocular signs may be seen with Bracken poisoning?
Hyphaema
What pathogen is associated with Infectious Bovine Keratoconjuncitivits/New Forest Eye/Pink eye?
Moraxella bovis
or Mycoplasma, pneumonia viruses
Is Infectious Bovine Keratoconjuncitivits/New Forest Eye/Pink eye positive or negative to fluorescein?
Positive
Name some risk factors for Infectious Bovine Keratoconjuncitivits/New Forest Eye/Pink eye
Flies
Woodland
Dust
UV light
What is the treatment forInfectious Bovine Keratoconjuncitivits/New Forest Eye/Pink eye?
Cloxacillin ointment
Sub-conjunctival oxytetraycline or amoxicillin
Suture eyelids closed, eye patches or keep indoors (photophobia)
IBR can cause ocular manifesatations. What virus causes IBR?
BHV-1 - latent in trigeminal
How is IBR diagnosed?
ELISA
Immunofluoresence
How does lead poisoning affect the eye?
Causes mydriasis (pupil dilation)
How is lead poisoning treated in catte?
EDTA
IV sedation
Magnesium (IM or SC)
Consider euthanasia - poor Px and long milk withdrawal
Listeriosis can cause encephalitis, facial paralysis and depression. What is seen on a menace test with listeria?
Eye retracts
What antibiotics are used to treat listeriosis?
Oxytetracycline
Penicillins
What virus causes malignant catarrhal fever?
Ovine herpes virus 2
Malignant catarrhal fever is always fatal. How is it diagnosed?
ELISA
Malignant catarrhal fever causes pyrexia, encephalitis and depression, nasal/mouth erosions, respiratory signs and lymph node enlargement. What eye lesions does it causes?
Blepharospasm
Conjunctivitis
Oedema
Centripetal corneal opacity
How can septicaemia present in the eye? (what is the ocular manifestation for septicaemia)
Hypopyon - inflammatory cells in the anterior chamber
What cow breed and age are predisposed to an ocular SCC?
Hereford
Older animals >5
Occular SCC are not related to UV light and are very invasive. What is the treatment?
Surgical removal - may recur
Or enucleation
Vitamin A deficiency is seen in which cows?
Growing indoor cattle
Fed on straw/cereal
What are the occular manifestations of vitamin A deficiency?
Night blindness
Negative menace response
Dilated pupils
Oedema of optic disc
