Diseases of the bovine eye Flashcards
1
Q
What are primary diseases of the eye?
A
- Infectious bovine kerato-conjunctivitis - New Forest eye, Pinkeye
- Bovine iritis - silage eye
- Squamous cell carcinoma - cancer eye
2
Q
What causes New forest eye?
A
- Moraxella bovis
-sometimes mycoplasma spp
3
Q
What can IBK present as?
A
- Lachrymation
- Blepharospasm
- Keratitis
- Ulcer
- Pannus - vascularisation
4
Q
What is treatment of new forest eye?
A
- LA eye ointment (orbenin-cloxacillin)
- Sub-conjunctival injection - oxytet
- Suture - eyelids
- Eye patches
- Photophobia = keep indoors
5
Q
What are risk factors for IBK?
A
- Flies
- Woodland
- Dust
- Chaff
- UV light
- Virus / pneumonia
6
Q
How can you prevent new forest eye?
A
- Fly control - ear tags, pour-ons, permethrins
- Graze away from fly habitat
- Ventilation + fly control inside
- Vaccine - USA
7
Q
What is bovine iritis associated with?
A
- Big bale silage feeding
- Winter
- Immune mediated reaction due to bacteria in silage going into eyes - problem from inside the eye = doesn’t show damage on fluorescein
8
Q
CS of bovine iritis?
A
- Early cases = constricted pupils
- Patchy / multiple areas of corneal opacity
- Glaucoma
- White flocules in anterior chamber
- later = vascularisation
9
Q
What is treatment of bovine iritis?
A
- Sub-conjunctival injection of
-atropine
-dexamethasone - +/-antibiotics
10
Q
What animals get squamous cell carcinoma?
A
- Breed disposition = herefords
- Older animals (>5y/o)
- Related to UV exposure
11
Q
What should be done with SCC?
A
- Invasive = involving = cornea, third eyelid, conjunctiva
- Surgical removal / enucleation
12
Q
What are common foreign bodies of the eye?
What can it lead to?
A
- Grass seeds
- Straw
- Can lead to keratitis
13
Q
What are secondary eye diseases?
A
- Malignant catarrhal fever
- IBR
- Listeriosis
- BVD
- Septicaemia
- Endotoxaemia
14
Q
What is malignant catarrhal fever?
A
- Ovine herpes virus 2
- Invariably fatal
- can be transmitted from sheep or buffalo
15
Q
What are clinical signs of malignant catarrhal fever?
A
- “head and eye form” most common
- Persistent pyrexia 41°C
- Depressed - encephalitis
- Nasal & mouth erosions
- lymph nodes enlarged
- Respiratory signs
- Diarrhoea