LA EctoParasites

Question 1

Fleas

Answer 1

Ctenocephalides - common problem in housed animals
Requires Tx on animal and environment

Question 2

Approved products for fleas

Answer 2

pyrethroids, IGRs, organophosphate in environment

Question 3

Lice

Answer 3

Biting and sucking species
Common in the winter - come from dam
Life cycle is roughly 4 weeks

Question 4

Pathogenesis of lice

Answer 4

Low infestation can be sub clinical, can see hypersensitivity
Blood loss and anemia can follow infection - pruritus is common
Severe infection: immunosuppressed, malnourished, young

Question 5

Cattle lice

Answer 5

More seen in winter - sucking lice produce anemia
Pruritus, alopecia, weight loss, leather damage
- can spread bovine Dermatomyocosis ***

Question 6

Controlling cattle lice

Answer 6

Macrocyclic lactones
Pyrethroids
OPs
IGR/IDI
environmental control is not needed

Question 7

small ruminant lice

Answer 7

Biting is more common but harder to treat
Can cause substantial pruritus, alopecia, raw skin, weight/milk loss, ruin wool production
**sheer sheep prior to treatment*

Question 8

Equine lice

Answer 8

Biting is more common - likely in winter
Easy transmission from brushes/blankets

Question 9

Porcine lice

Answer 9

ONLY one species: haematopinus suis
Sucking lice - bigger bodies = easier to spot
Treat w macrocyclic lactones inj or pyrethroids

Question 10

Clinical signs of haematopinus suis

Answer 10

Rubbing, restless behavior
Production losses in growers-finishers
= decreased feed intake/efficiency

Question 11

Large animal mites

Answer 11

Similar cycle to lice
Transmitted by direct contact due to limited environmental survival
DX w skin scarping although its not a common case

Question 12

Sarcoptes

Answer 12

PIGS - backyard operations
Decreased growth rate/feed efficiency, trimming on lesions /meat at slaughter, scratching= damage to skin/facilities, ^^stress

Question 13

DX and TX of sarcoptes in pigs

Answer 13

Skin scraping
Ivermectin /doramectin inj - x2/14d
Must treat ALL animals
Tx/isolate new pigs

Question 14

Sarcoptes in LA

Answer 14

RARE - can see in lesions
Reportable condition in sheep
Tx w macrocyclic lactones

Question 15

Chorioptes in LA

Answer 15

MOST IMPORTANT MITE IN LA
Common in EQ and small rum - legs/low body
Forms papules/crusts on effected areas - can migrate
DX off clinical signs & skin scraping* present in low #
NEED COMBO THERAPY - inj and topical

Question 16

Demodex in LA

Answer 16

Assume they came from local dogs
Presents w nodular lesions - FILLED w mites/sebum which can rupture, sever hypersensitive reactions can happen
No approved treatment

Question 17

Psoroptes ovis

Answer 17

Causes serious mange
REPORTABLE

Question 18

Reportable mites in LA

Answer 18

SARCOPTES
CHORIOPTES
PSOROPTES

Question 19

Tick species in LA

Answer 19

Dermacentor variabilis
Ixodes scapularis
Amblyomma americanum

Question 20

Dermacentor albipictus

Answer 20

winter tick
ONE host tick - all 3 stages feed on ONE host
Important in moose, horses and ruminants
North US and Canada

Question 21

Rhipicephalus annulatus
Rhipicephalus microplus

Answer 21

North American cattle tick
Asian blue tick
ONE host tick
Cause Texas cattle fever and spread bovine Babesiosis
Mostly eradicated from us

Question 22

Amblyomma in LA

Answer 22

A. Americanum - causes Q fever
A. Maculatum - gulf coast tick
Causes heart water (Ehrlichia) lepto, rickettsia, Hepatozoon

Question 23

Amblyomma maculatum

Answer 23

Commonly attach to ears of cattle
Produce thick/edema ears when 10+ ticks attach which causes cartilage damage, fibrosis = gotch ear/droopy ear

Question 24

Flies

Answer 24

Warbles (bots, grubs) in LA
Cattle grub (hypoderma) causes skin lesions
Other species in EQ and sheep do not cause skin lesions

Question 25

Life cycle of cattle grubs

Answer 25

Hypoderma Bovis and hypoderma lineatum
“Gadding” - adult behavior running away from flies
Eggs are glued to hairs on low body
Larvae hatch and burrow through skin to tissue - around esophagus (lineatum) or spinal cord (bovis) for 2-4 m
Then migrate back to subq on back = nodule for 5-8w
Pupate on ground*

Question 26

Clinical signs and loss of cattle grubs

Answer 26

**lumps on back
Economic loss:
Adults - gadding
Larvae - migration causes tissue damage
Can interfere w esophageal function/NS function

Question 27

Warning on macrocyclic lactones label

Answer 27

Nov1-March1 do not use ML
Effective timing for TX is at the very end of fly season

Question 28

Flies of importance in horses

Answer 28

Stomoxys
Culicoides
Tabanids

Question 29

Important flies in cattle

Answer 29

Haematobia
Musca autumnalis
Stomoxys

Question 30

Important flies for small rum /pigs

Answer 30

Stomoxys - housing

Question 31

Types of pesticides

Answer 31

Organophosphate and carbamates
Pyrethroids
Macrocyclic lactones

Question 32

Effect of organophosphate and carbamates

Question 33

Effect of pyrethroids

Question 34

Effect of macrocyclic lactones

Question 35

Pesticides for cattle

Answer 35

Pyrethroids and ML - most common
Organophosphates
IGR/IDI

Question 36

Pesticides in horses

Answer 36

Pyrethroids - almost only one available
IGR/IDI
Very limited organophosphate use

Question 37

Environmental control

Answer 37

Ear tags, fly bags

Question 38

Biting horse flies

Answer 38

Can cause hypersensitive reactions - serious problem
Fly control is difficult
Products are mostly pyrethroids