Farm animal dermatology Flashcards
What is the main cause of skin disease in cattle
ectoparasites
What is the most important ectoparasite in cattle
lice (4 species- 1 biting, 3 sucking)
What is the most common ectoparasite of sheep
psoropties ovis - sheep scab mite
Describe the lifecycle of lice
live on skin surface
life cycle is direct and simple
whole life cycle happens on the host
Describe the epidemiology of lice in cattle
very common
more common in winter
don’t survive well off the host
describe the impact of lice in cattle
decreased BCS/ daily live weight gain
damaged skin
usually poor doers- often animals will have concurrent disease
List the 3 species of lice seen in cattle
Bovicola bovis
Linognathus vituli
Haematopinus eurysternus
what is the most common species of lice in cattle
Bovicola bovis
where is bovicola bovis generally seen in cows
on the head
is a chewing/ biting louse
Describe how you diagnose lice in cattle
they are big so visable with naked eye
List 3 methods of treatment for lice in cattle
Pour-on synthetic pyrethroid - kills everything
pour-on group 3-ML anthelmintics - kills everything
injectable group 3- ML anthelminitics - remove all sucking lice and >98% of biting lice - so not used as much
All cattle in direct contact must be treated
What is pink eye
Infectious bovine keratoconjunctivitis (IBK)
caused by the bacterium Moraxella bovis
how does infectious bovine keratoconjunctivitis get transmitted
face fly
what are the signs of infectious bovine keratoconjunctivitis
corneal ulcers
oedema
lacrimation
opacity
epiphora
what is the treatment for pink eye
antibiotics - IM
NSAIDs
describe how to prevent pink eye
fly control e.g. permethrin
biological control- parasitic wasps
Describe onchocerca
thin white worms found in the eye of cattle
transmitted by blackfly or culicoides
Describe the impact of the warble fly
gadding behaviour
ectopic migration and paralysis
downgrade of the hide
reduced reproduction
notifiable in Scotland
Describe how to treat warble flies
organophosphates
98% effective in autumn and less efficient in spring
What is the most common mite seen in catte
surface mite- chorioptes
Describe the clinical signs of chorioptic mange
tail mange
leg mange
scrotal mange
describe how you diagnose chorioptic mange
deep skin scrapes - from the edge of the lesion
what is the treatment for chorioptic mange
Permethrin (synthetic pyrethroid)
OR
pour on Macrocyclic lactones (injectable less effective)
What is the most common tick seen in cattle
Ixodes ricinus
List 5 consequences of ticks in cattle
poor body condition
intense irritation
weight loos and reduced milk yeilds
hide/fleece damage
vehicles for disease-causing agents
Name a viral disease that ticks can cause in cattle
Tick-borne encephalitis
List some bacterial diseases that ticks can cause in cattle
lyme borreliosis
Q-fever
tick-borne relapsing fever
what parasite can ticks transmit in cattle
babesiosis
Describe the clinical signs comonly seen with Babesia
pyrexia
severe haemolytic anaemia haemoglobinuria- red urine
death
Describe how you diagnose babesia
previous history - have the animals come onto marginal grazing recently
examination of skin often confirms presence of ticks
Describe the aetiology of photosenstisation
direct- due to defect (congential or acquired through ingestion) in animals metabolism of RBC
secondary- occurs in animals with liver damage
local- from reaction to the sap of some plants
What plant can cause photosensitisation in csttle
St Johns wort
Describe the clinical signs of photosensitisation
non-pigmentated skin affected
hair-loss reddening , peeling
ulceration of skin
Describe how you diagnose photosensitisation
on clinical signs
describe how you treat photosensitisation of cattle
removal to cool shaded housing
supportive therapy
treatment for liver failure
identify and remove possible plant sources of the photosensitising chemicals
