Skin Disease (Dairy Cattle) Flashcards
Why are dairy cattle more susceptible to skin lesions?
Raised in confinement, milking claw on udder and skin contact
What causes ringworm?
Dermatophycosis - Trichophyton verrucosum
Zoonotic - spore forming (in environment)
Transmission animal to animal, fomites
No show!
What aged cattle normally get ring worm?
Younger, confinement, head or neck then move anywhere (raised greyish scabby area with no hair)
Older- consider immune issue
How do you treat ring worm?
Self-limiting, no underlying disease or production losses
Topical - scrape off, wash with soap, iodine (2x day 14 days), clotrimazole (dont let lick, wont know withdraw)
clean barn tools
How do you know the ring worm is healed?
Hair growing out middle of lesion
What is primary photosensitizaiton?
Injection, injection or absorption of photodynamic agent
-High energy molecule that reacts to UV light in skin to release free radicals (Ulceration, necrosis and edema)
Healthy cows*
Non-pigmented skin, nose and udder
*Occurs when liver overwhelmed with chlorophyll turns into phylloerythrin in GIT
What kinds of plants cause primary photosensitizaiton?
Buckwheat, St. Johns wort, smart weed, Legume and Brassica, alfalfa, red clover, milk vetch, turnups, kale,
How do you treat primary photosensitization?
Stop intake, provide shade and treat secondary infection (Ceftiofur) and pain
What is Type II photosensitization?
inherited aberrant pigment metabolism
Genetic
congenital erythropoietic prphyria
-holstein, shorthorn and hereford
Pigmented skin too
What is the normal metabolism for Phylloerythrin?
Cow eats -> Chorophyll in GIT to Phylloerythrin->Phylloerythrin -> Liver
What is secondary Photosensitization?
**Unhealthy cattle with impaired hepatobiliary secretion - bile duct occulision hepatic dysfunciton
-toxin - pyrrolizidine alkalois, blue gren algae
*non-pigmented, icterus and poor prognosis for liver damage
How do you treat photosensitization?
Provide right quanity and quality for feed/forage
Imporve pastures with right weed control
What are some differentials for dairy teat lesions?
Bovine ulcerative mammilitis, pseudocowpox, bovine warts, teat-end hyperkeratosis
What causes bovine ulcerative mammilitis?
Bovine herpes virus
- cold weather, replicates at lower temps, more heifers, transmision by flies
What are some clinical signs of bovine ulcerative mammalitis?
decreased milk and increased mastitis
Edematous lesions, vesicles that rupture, ulcerated areas that scab, painful and resist milking
What is treatment for bovine ulcerative mammalities?
Iodophore teat dip with emollients, isolate cows and milk last with different equipment
How long does bvine ulcerative mammilitis last?
4 week course
What causes Pseudocowpox?
parapoxvirus
What are clinical signs of pseudocowpox?
small red papules ot vesicles/pustules, smalll scabs form aroudn the granulation tissue, lesion can persist for several months, short immunity, reinfection possible
Is psedocowpox zoonotic?
Yes, wear gloves and wash hands (change gloves if suspect)
What agent causes bovine warts?
papilloma virus
What are clinical signs of warts?
Small raised, nonpainful lesion, filamentous or front like, interfere with milking
-Direct or indirect contact transmision
What is hyperkeratosis?
Non-infectious hardening and roughening of the skin
-Keratin part of skin - look for at end of teat (score 1-4)
Goal: <5% scoring 4 and less than 15% 3s
What are some risk factors for hyperkeratosis?
long pointy teat, older cow, later lactation, longer time for milking machine, genetics, higher vacumm on machine, move in liner, frequency of milking
Why is hyperkeratosis bad?
pathogens can hand out in teat
How do you prevent teat end hyperkeratosis?
ensure proper milk let down, (timing and claw), adjust automatic take off if needed, teat cleansing and post dip with emollients
What is udder edema?
Impaiered blood and lymph circulation - fetal pressure, decreased protien oncotic pressure as IgGs
-Heifer
-genetis and dry cow nutrition
What is udder cleft dermatitis?
Necrotic, fooul, smelly scabby area - between 2 halves of udder, cranial and on midline
-associated with sarcoptic mange- scrape
Treatment: clean with antibacterial daily, dry thorough, mild astringent
