Farm dermatology

Question 1

Common problems

Answer 1

Infectious
Neoplasia
Nutritional
Toxic
Physical
Congenital

Question 2

Ectoparasites

Answer 2

Indoor- lice and mites
Outdoors- flies, ticks

Question 3

Pediculosis

Answer 3

Lice on back and neck
Pruritis
Lice and eggs visible macroscopically
Microscopic speciation
Sucking- lignonathus vituli, haematopinus
Chewing- bovicola bovis

Question 4

Mites

Answer 4

Acariasis / mange
Psoroptes bovis
Chorioptes bovis
Sarcoptes scabei
Pruritus, rubbing hair loss in housed cattle
Dx- skin scrape, liquid parrafin smear microscopy
Neck and face- sarcoptes
Elsewhere- the other 2

Question 5

Ectoparasite Tx

Answer 5

Pediculosis and mange
Management and mange
Mild infestations Tx may not be needed
Self limiting
ML, SP (lice resistance reported)

Question 6

Trichophyton verrucosum

Answer 6

Ringworm
Youngstock
Circular raised crusted plaques
Dx- culture and microscopy from peripheral lesion hair pluck
Tx- clean and disinfect housing
-Turn out (UV sensitive)
-Topical enilconazole
- Vax lowers severity (prophylaxis)

Question 7

Pustular impetigo

Answer 7

Staph
Wounds, udders, perineum
Poorly applied ear tags

Question 8

Abscess and cellulitis

Answer 8

Actinobacilli (T pyogens)
Lower jaw and popliteal LN
Can be associated with Sys Dz
Open drain and Ab

Question 9

Bacterial Dz

Answer 9

Draining fistulas
Lumpy jaw - actinomyces bovis
Wooden tongue - actinobacillus ligniersii
Rain scald - Dermatophilosis congolensis
-wet weather, skin microtrauma
-topical disinfectant, penicillin

Question 10

Viral Dz

Answer 10

Papillomatosis - warts
- common and self limiting (can remove Sx)
Stomatitis/vesicular Dz
-self limiting
-papular stomatitis - muzzle
-herpes mammilitis - udders
-may indicate systemic Dz

Question 11

Nutritional

Answer 11

Deficiencies
Poor coat
Responds to multivitamin injections
Cu def/ Mb tox
-poor growth, brown tinged coat w/ glasses

Question 12

Toxic

Answer 12

Photosensitisation
Unpigmented skin affected
Photodynamic agents ingested
2° hepatogenous damage
House out of sun
Tx CS

Question 13

Sheep

Answer 13

Rubbing- pruritus
Wool break- nutritional, systemic Dz
Trapping
Dog attacks

Question 14

Psoroptes ovis

Answer 14

Sheep scab
Allergic reaction to mites and faeces
Concentric wool loss with scaling and crusting
Dermatitis 2° Dz
Slow Dz
Dx- skin scrape
Tx- OP dip
Mandatory Tx in England
Whole flock recommended

Question 15

Bovicola ovis

Answer 15

Pediculosis
Often incidental finding
Pruritis
Dx- macroscopic in fleece, skin scrape
Underlying cause
Shear flock
Topical SP

Question 16

Orf

Answer 16

Viral zoonosis
Mouth, feet, teats (lambs and mastitis ewes)
Self limiting (<1m)
Biosecurity important
Ab for 2° Dz
Vax (not in naive flocks)

Question 17

Clinical signs of urinary Dz

Answer 17

Abdominal pain – pyelonephritis, calculi.
Dysuria – pyelonephritis, calculi, cystitis, (vaginitis).
Haematuria ± pus ±calculi.
Polyuria – diabetes mellitus (post FMD), diabetes insipidus, idiopathic (calves).
Anuria – obstruction by calculi.
Oliguria – prerenal, renal or post renal.
Proteinuria – renal amyloidosis - breed.

Question 18

Normal urine

Answer 18

1.02-1.045
Alkaline pH
Trace protein
Trace glucose

Question 19

Renal Dz

Answer 19

Pyelonephritis
Toxic nephrosis
Amyloidosis - glomerulonephritis
Embolic nephritis - post septic event

Question 20

Pyelonephritis

Answer 20

Corynebacterium renale, some E coli
Suckler cows, 2° to trauma
CS- Chr weight loss, dysuria, blood and pus in urine
-Per-Rect - swollen painful kidney
Tx- long course AB (oxytet)

Question 21

Enzootic haematuria

Answer 21

Haemangiomata in bladder
Long term bracken ingestion,
-bright blindness, gut tumours, bone marrow tox, bloody D+
Older cows
Blood clots in urine

Question 22

Haemaglobinuria

Answer 22

Bacilliary- SW UK, fluke, soil& dormant in liver, fatal
Post part- Old high yielders, low P diet
-sudden onset
-Tx-P (catasol) and blood transfusion
Redwater
-babesia divergens (I ricinus)
-port wine urine, pipe stem faeces
-blood smear, ELISA (herd exposure)
-Tx imidocarb, support

Question 23

Urolithiasis general

Answer 23

2-4m ram lambs/ pre breeding lambs
Mature goats (early castration)
Bull beef calves
Ca or struvite
Ca:P imbalance, H2O deprivation, diet change (mature animals)
Burdizzo incompetence
-placed too high, rupture urethra, water belly signs

Question 24

Urolithiasis presentation

Answer 24

Restlessness
Abdominal pain
Strain (hiccups?)
Dysuria
Progress until rupture
-upon rupture will appear better
–high urea and creatinine in abdominal fluid

Question 25

Urolithiasis Dx

Answer 25

Abd palpation- distended bladder, (swelling loc. ind. rupture sit)
Sand around preputial orifice
Water belly (swelling in abdomen, rupture), incise and drain
Imaging - free fluid in Abd
Per-rect- palpate urethra

Question 26

Tx urolithiasis

Answer 26

Relaxants - buscopan
Sx-
-remove vermiform appendage (not for early castrates)
-cystotomy
-perineal urethrostomy
-bladder marsupialisation
Catheterisation- poor access in young
-epi Dam -> causes stricture
-per cutaneous (palpably fix and US visual) Foley catheter, Rutgers percutaneous

Question 27

Prevention of urolithiasis

Answer 27

Check diet
Don’t add Mg for growing rams
Monitor for urine scald
Fly strike precautions