Exam 1 - FA Dermatologic Diseases Flashcards
1
Q
what species are affected by pediculosis? which is most common of these?
A
cattle, sheep, goats, & llamas
goats
2
Q
what is the causative of pediculosis?
A
sucking/biting lice
3
Q
what environments are favorable for pediculosis?
A
winter & confined animals
4
Q
what is the biggest difference between clinical signs of biting lice vs. sucking lice?
A
biting - pruritic
sucking - pruritic & anemia
5
Q
how is pediculosis transmitted?
A
direct contact & fomites
6
Q
how is pediculosis diagnosed?
A
exam the hair coat
7
Q
why may I use ivermectin in an animal with pediculosis?
A
systemic medication to get the sucking lice!
8
Q
T/F: topicals that are safe for cats are probably safe for camelids
A
true
9
Q
what are your treatment options for pediculosis?
A
ivermectin & topical insecticides
10
Q
what are the three main mites we see in food animals? which is most common?
A
psoroptic, chorioptic, & sarcoptic
chorioptic
11
Q
what kind of mites affect sheep?
A
psoroptes ovis
12
Q
what mites typically affect pigs?
A
sarcoptes
13
Q
until proven otherwise, what mites are on small ruminants?
A
chorioptes
14
Q
T/F: demodectic mites are rare in food animals
A
true
15
Q
T/F: mites are relatively host-specific
A
true
16
Q
what mites do not burrow?
A
psoroptes & chorioptes
17
Q
what mite burrows?
A
sarcoptes
18
Q
how are mites diagnosed?
A
skin scrapings & ear swabs
19
Q
what mite has jointed pedicles?
A
psoroptes
20
Q
what mites have non-jointed pedicles?
A
sarcoptes
21
Q
what mites have short pedicles?
A
chorioptes
22
Q
what sheep breed is most susceptible to psoroptic mange?
A
merino
23
Q
T/F: psoroptes cuniculi is transmissible to humans
A
false
24
Q
what is the life cycle of psoroptes cuniculi? why is this important?
A
2 week life cycle on the host but can survive in the environment for weeks
treat the environment too!!
25
are psoroptic mites pruritic?
yes
26
what are the clinical signs of psoroptic mange in sheep?
papules & crusts in wooled areas
intense pruritus - IgE vs mite antigens
secondary staph infections
27
what bug should you report in sheep???
psoroptic mange!!!
28
chorioptic mange typically causes lesions where?
legs/feet & often on scrotum/perineum
29
how is chorioptic mange diagnosed?
skin scrapings
30
is psoroptic or chorioptic mange more pruritic?
psoroptic
31
T/F: chorioptic mites only survive off the host for a few days
true
32
what is the treatment for chorioptic mange?
ivermectin for 3 weeks
topical treatment 2-3x a week
33
what mange is transmissible to humans?
sarcoptes scabei
34
what is the life cycle of scabies?
10-17 day life cycle
35
how does scabies progress?
starts at the head/ears/neck & then becomes generalized
36
T/F: scabies are burrowing mites that cause pruritus
true
37
T/F: a negative skin scrape for scabies doesn't rule it out
true - small numbers are present & you may see it on a biopsy
38
how is scabies diagnosed?
can try a skin scrape & biopsy
often diagnosed based on clinical suspicion/response to treatment
39
how is scabies treated?
topicals or systemic ivermectin
40
what is an important differential for pruritic sheep!!
scrapie!!!
41
what is fly strike?
flies feed on open wounds with necrotic tissue causing discomfort
42
how is fly strike treated?
topical - clip/clean area & manually remove maggots
systemic - antibiotics if febrile, appears septic, & possibly ivermectin
43
how is fly strike prevented in sheep?
shearing around the head, perineum, & ventrum of males
44
what is the fancy name for sheep keds?
melophagus ovinus - wingless flies
45
what is the life cycle of melophagus ovinus?
3 week life cycle on host with adults as blood suckers
46
what are the clinical signs of sheep keds?
pruritus, stained wool, skin nodules, anemia, & weight loss
47
what is this?
wingless flies!! sheep keds!!
48
what is the treatment for sheep keds?
LOTS OF THEM!!
prevent!!!
treat animals topically after shearing
49
where is hypodermiasis common?
in cattle in the northern hemisphere worldwide
50
why does hypodermiasis cause economic losses?
hide damage, weight loss, cause stampedes, 'gadding', 'fly worry', & animals will stand in water and not eat
51
what are the 2 species of hypoderma?
hypoderma bovis
hypoderma lineatum
52
what is the life cycle/pathogenesis of hypodermiasis?
eggs are laid on legs (h. lineatum) or rump (l. bovis) & hatch in 3-7 days
penetrate the skin & migrate in SQ layers
in late fall/early winter - h. lineatum to esophagus & h. bovis to spinal canal
L1 remains there 2-4 months
jan/feb larvae go to SC tissues of back & cut a breathing hole through the skin, molt from L1-L3 over 4-6 weeks
L3 falls off & pupates to adult in 1-3 months
53
what are the clinical signs of hypodermiasis?
SQ nodules, posterior paralysis, bloat, & anaphylaxis
54
how is hypodermiasis diagnosed?
presence of nodules on the animal
55
what is the treatment for warbles in hypodermiasis?
physical removal
56
what is the treatment for larvae in hypodermiasis?
organophosphates, macrocyclic lactones
avoid treatment during the 2-3 months before the expected appearance of grubs along the back (not treatment from october 1st-march 1st)
57
what animals are affected by stephanophilariasis? what is the agent?
cattle - stephanophilaria stilesi
58
how is stephanophilariasis transmitted?
horn flies
59
what are the clinical signs of stephanophilariasis?
papules, crusts, ulcers, & hyperkeratosis
60
how is stephanophilariasis diagnosed?
by appearance & location of lesions
61
what is the treatment for stephanophilariasis?
there is none
62
what disease is this lesion associated with?
stephanophilariasis
63
what is hanging out in this tissue biopsy?
scabies!!
64
what is a dermatophyte?
unique fungi that invades & lives in keratinized tissue
65
what 3 genera of dermatophytes are common in food animals?
microsporum
trichophyton
epidermophyton
66
what animals are affected by trichophyton verrucosum?
cattle & goats
67
what animals are affected by trichophyton mentagrophytes?
cattle & goats
68
what animals are affected by microsporum nanum?
pigs & llamas
69
what is this?
microsporum dermatophyte
70
what is this?
trichophyton dermatophyte
71
what is this?
epidermophyton dermatophyte
72
why does dermatophytosis cause alopecia?
dermatophytes invade keratinized structures (hair, stratum corneum, horns, claws), & with the invasion of the hair shaft, it becomes weakened & breaks off
73
why does transmission of dermatophytosis vary?
amount & period of exposure
immuno-competency of the animal
& IT IS ZOONOTIC
74
what are the clinical signs of dermatophytosis?
alopecia (centrifugal pattern, the ring), crusts, erythema, papules, +/- pruritus (typically not pruritic), & claws/hooves weaken & split
75
how is dermatophytosis diagnosed?
90% - fungal culture
microscopic examination of hair/crusts with a KOH prep, but difficult to do
biopsy - quick & use special stains, dx 70% of the time
76
what is the treatment for large areas of dermatophytosis?
lime sulfur 5% 2x/week
bleach 1:10 solution but not in black show animals
chlorhexidine
77
what is the treatment for small areas of dermatophytosis?
shampoos or rinses with miconazole or ketaconazole plus chlorhexidine
78
what species are affected by papillomatosis? what is the causative agent?
cattle
papillomavirus
79
what animals are more so affected by papillomatosis?
confined & young animals
80
how is papillomatosis transmitted?
direct contact & fomites
81
what clinical signs are associated with papillomatosis BPV-1?
teats & penis affected
82
what clinical signs are associated with papillomatosis BPV-2?
head & neck affected
83
what clinical signs are associated with papillomatosis BPV-3?
atypical - body affected
84
what clinical signs are associated with papillomatosis BPV-4?
gi affected
85
what clinical signs are associated with papillomatosis BPV-5?
rice grain
86
what clinical signs are associated with papillomatosis BPV-6?
teat & udder affected
87
how is papillomatosis diagnosed?
appearance & skin biopsy
88
what is this lesion of?
papillomatosis
89
what is the treatment for papillomatosis?
spontaneous regression
surgical resection, cryotherapy, hyperthermia, & vaccine
90
what species are affected by dermatophilosis?
cattle, sheep, goats, & llamas
91
what is the causative agent of dermatophilosis?
dermatophilus congolensis
92
what animals are predisposed to getting dermatophilosis?
animals with skin damage, wet environments, & carrier animals
93
how is dermatophilosis transmitted?
direct contact & fomites
94
this lesion is consistent with what disease?
dermatophilosis
95
what are the clinical signs of dermatophilosis?
papules, pustules, & purulent exudate under thick scabs
96
how is dermatophilosis diagnosed/
direct smear, minced crust smear, & culture
97
what is the treatment for dermatophilosis?
remove crusts & dry out lesions
penicillin
oxytetracycline
98
what is the causative agent in this picture?
dermatophilus congolensis
99
what is the causative agent of caseous lymphadenitis?
corynebacterium pseudotuberculosis
100
what species are affected by caseous lymphadenitis?
sheep & goats
101
how is caseous lymphadenitis transmitted?
direct contact, inhalation, & ingestion
102
what does this animal have?
caseous lymphadenitis
103
why am I worried about caseous lymphadenitis in the long term?
can cause long term biosecurity problems in the herd if there are SQ abscesses
104
what are the clinical signs of caseous lymphadenitis?
lymph node abscesses, internal abscesses causing organ dysfunction in the liver, lungs, & kidneys, & weight loss
105
if you have sheep/goat presenting with chronic weight loss, what should be on your differential list?
caseous lymphadenitis
106
how is caseous lymphadenitis diagnosed?
appearance, culture, & serology (SHI test)
107
how is caseous lymphadenitis treated?
benign neglect
lance/drain/flush
surgical removal
108
how is caseous lymphadenitis prevented?
vaccination
109
what species are affected by contagious ecthyma?
sheep, goats, & llamas
110
what is the causative agent of contagious ecthyma?
parapoxvirus
111
what is the epidemiology of contagious ecthyma?
endemic on farms & periodic outbreaks
112
how is contagious ecthyma transmitted?
direct contact & scabs in the environment
113
what are the clinical signs of contagious ecthyma?
papules, vesicles, crusts, scabs, pain, & anorexia
114
what is your differential?
contagious ecthyma
115
how is contagious ecthyma diagnosed?
clinical signs & biopsy
116
how is contagious ecthyma treated?
spontaneous resolution & supportive care
117
how is contagious ecthyma prevented?
vaccination
118
can a human get contagious ecthyma?
yup
119
what species are affected by photosensitization?
cattle, sheep, goat, llamas
120
what is causative agents of photosensitization?
photodynamic agents in the skin
hepatic disease/failure
121
what is the mechanism of primary photosensitization?
plant/chemical contains a photodynamic agent or metabolite
122
what is the mechanism of secondary photosensitization?
liver disease leads to accumulation of phylloerythrin in skin - phylloerythrnis are a breakdown product of chlorophyll
123
what is the mechanism of porphyria photosensitization?
abnormal heme synthesis, poryphrin accumulation, & genetic
124
what plants cause primary photosensitization?
st. john's wort - hypericin
buckwheat - fagopyrin
perrennial ryegrass - perloline
cocoa shells
125
what chemicals cause primary photosensitization?
phenothiazines, thiazides, methylene blue, tetracyclines, & sulfonamides
126
how is photosensitization treated?
decrease exposure to sunlight
remove exposure to photodynamic agent or liver toxin
supportive care for treating liver disease - keep the animal eating & use antibiotics if needed
127
what species if affected by erysipelas?
swine
128
what is the causative agent of erysipelas?
erysipelothrix rhusiopathiae
129
what is another name for erysipelas?
diamond skin disease
130
how is erysipelas transmitted?
through infected animals & environmental contamination
131
what are the acute clinical signs of erysipelas?
sudden death, fever, walking stiffly on toes, anorexia, thirst, red to purple widespread discoloration on the ears, snout, & abdomen, & diamond shaped skin lesions
132
what's your differential?
erysipelas
133
what are the subacute clinical signs of erysipelas?
diamond shaped skin lesions, anorexia, & fever
134
what are the chronic clinical signs of erysipelas?
arthritis & valvular endocarditis
135
how is erysipelas diagnosed?
skin lesions are pathognomonic
isolation of organism from tissues
136
what is the treatment for acute erysipelas?
penicillin - rapid response
137
what is the chronic treatment for erysipelas?
difficult in production pigs & pets
138
how is erysipelas prevented?
vaccination - 3 to 4 weeks before farrowing & every 6 months
139
why is it concerning that erysipelas is zoonotic?
can lead to endocarditis & septicemia
140
what is the scientific name for greasy pig disease?
exudative epidermitis
141
what species are affected by exudative epidermitis?
swinde - few days to 8 weeks
142
what is the causative agent of exudative epidermitis?
staphylococcus hyicus
143
what is the epidemiology of exudative epidermitis?
unclear! presence doesn't indicate disease
may be pustular dermatitis & suppurative folliculitis
144
what are the clinical signs associated with exudative epidermitis?
listlessness, anorexia, reddened skin, brown exudative spots, may become generalized over 24-48 hours, & may be fatal
145
what's your differential?
exudative epidermitis
146
how is exudative epidermitis diagnosed?
clinical signs, culture, & histopathology
147
what is the treatment for exudative epidermitis?
unrewarding - antimicrobials & chlorhexidine baths
148
how is exudative epidermitis prevented?
sanitation & good hygiene
149
what species are affected by zinc responsive dermatosis?
camelids, goats, cattle, & sheep
150
what are the causative agents of zinc responsive dermatosis? what is the epidemiology?
low zinc diets
antagonist diets
hereditary problems
may affect one or many animals
151
what are the clinical signs of zinc responsive dermatosis?
dull haircoat, scaling, alopecia, & hyperkeratosis
152
how is zinc responsive dermatosis diagnosed?
plasma zn - royal blue top tube
response to therapy - poor option
153
what is the treatment for zinc responsive dermatosis?
zinc supplementation - be wary of declining copper
