Horse 1

Question 1

Choriptes sp

Answer 1

-surface mites of horses, cattle and sheep
-causes chorioptic mange

Question 2

Diagnosis of chorioptic mange

Answer 2

-clinical appearance
-can be asymptomatic
-superficial skin scrapings with KOH digest

Question 3

Clinical signs of chorioptic mange

Answer 3

-pruritus of pastern, heel, feathers
-pruritis of tailhead

Question 4

Treatment/control

Answer 4

-off label topical macrocyclic lactones/foot washes
-treat repeatedly- whole herd and cattle/sheep

Question 5

Ticks in horses

Answer 5

1. dermacentor albipictus
2. dermacentor variabilis
3. dermacentor andersoni
4. Ixodes species
5. Otobius megnini

Question 6

What is carried by Ixodes scapularis and ixodes pacificus?

Answer 6

-Anaplasma phagocytophilium
-Borrelia burgdorferi

**Anaplasmosis rare in horses, lyme disease rare

Question 7

What is carried by Dermacentor andersoni?

Answer 7

-paralysis in BC

Question 8

What is carried by Bebedia caballi and Theileria equi?

Answer 8

-equine piroplasmosis, NOT in CANADA

Question 9

Diagnosis of ticks

Answer 9

-direct observation
-collect and store fresh, frozen, or in ethanol
-ID genus species
-test for tick borne pathogens if clinical

Question 10

Treatment and control of ticks

Answer 10

-manure removal
-environmental modification
-topical repellents (sprays, wipes, powders)
-moxidectin, isoxazolines

Question 11

Lice of horses

Answer 11

1. Damalinia equi
2. Haematopinus asini

Question 12

Damalinia equi

Answer 12

-chewing
-located on dorso-lateral trunk
-eggs at base of hair

Question 13

Haematopinus asini

Answer 13

-sucking
-mane, tailhead, fetlocks
-eggs at base of hair

Question 14

Equine pediculosis

Answer 14

-most often infected in winter and early spring during times of close housing, long coats and humidity

-can live off host for up to 3 weeks

-species specific, does not carry other diseases

Question 15

Which individuals are most at risk for equine pediculosis?

Answer 15

-those with thick coats, young foals, senior horses, pregnant mares, and ill or weak

Question 16

Diagnosis of lice

Answer 16

-history
-often asymptomatic
-hair loss, irritation, pruritis, dandruff (anemia)
-nits on base of hair, recovery and ID of adult

Question 17

Treatment of lice

Answer 17

-topical pesiticides (sprays, wipes, powders, shampoos
-systemic/oral ML for sucking lice
-treat repeatedly
-highly contagious= treat all horses in herd

Question 18

Gasterofilus

Answer 18

-bot flies
-1 year life cycle

Question 19

Gasterophilus life cycle

Answer 19

1. Eggs laid on hairs in summer
2. Often chew and eat the larvae (L1)
3. L1 in gingiva, then L2 and L3 stages in GI tract during winter
4. L3 released into environment in spring where they become pupae and then adult flies

Question 20

3 species specifics of Gasterophilus life cycle

Answer 20

1. Gasteriphilus intestinalis
2. Gasterophilus nasalis
3. Gasterophilus haemorrhoidalis

Question 21

Gasteriphilus intestinalis

Answer 21

eggs on forelimbs and shoulders, L3 in cardiac region of stomach

Question 22

Gasterophilus nasalis

Answer 22

-eggs in inter mandibular region, L3 in pylorus and proximal duodenum

Question 23

Gasterophilus haemorrhoidalis

Answer 23

eggs on hair of mouth and lips, L3 in rectum

Question 24

Diagnosis of bots

Answer 24

-history and clinical appearance
*usually asymptomatic
*can have high anorexia, colic, anemia, cachexia

-eggs on tips of hair (not base!)
-L3 on gastroscopy passed in feces in spring
-adults are cause of dangerous behaviour in some horses while laying eggs

Question 25

Treatment of bots

Answer 25

-ivermectin or moxidectin in fall after first frost

-higly effiacious= motivation

Question 26

Stomoxys calcitrans

Answer 26

-stable fly
-females blood feed, lay eggs in old manure/rotting vegetation
-IH for Habronema and Draschia

Question 27

Appearance of Stomoxys calcitrans

Answer 27

-arista
-four longitudinal dark stripes on thorax
-prominent forward projecting proboscis

Question 28

Tabanids

Answer 28

-horse fly, deer fly, clegs
-slash feeders with painful bites
-females blood feed
-mechanical disease transmission= equine infectious anemia and anthrax

Question 29

Appearance of tabanids

Answer 29

-stout antennae
-no arista
-often banded/patterned eyes
-mouthparts face down

Question 30

Culicoides spp

Answer 30

-midges
-specifically C. sonorensis in Canada, near US border, Okanagan)

-adult females blood feed
-lay eggs in moisture and water
-spread Onchocerca and viruses such as Vesicular stomatitis, African horse sickness)
-leads to hypersensitivity= queensland or sweet itch)

Question 31

Sweet itch

Answer 31

-caused by Culicoides spp
-allergic rxn to saliva of midges
-causes papules on skin (mane and tail)
-horses may rub=hair loss and scabs

Question 32

Treatment for sweet itch

Answer 32

-bring horses inside
-use mesh screens, fly sheets, insect repellants, stall fans
-feed omega 3
-limit breeding grounds (standing water)
-can use topical steroid creams/systemic antihistamines

Question 33

Culicidae

Answer 33

-mosquitoes (culex tarsalis, C. pipens, Aedes sp)
-many species in Canada; long legs and antennae
-major public health significance (malaria, trypanosomes, viruses)

Question 34

What are culex tarsalis, and C pipens vectors for?

Answer 34

WNV, WEEV, EEV

Question 35

What is Aedes spp a vector for?

Answer 35

-Setaria equina (nematode)

Question 36

Negative effects of biting flies

Answer 36

-hypersensitivity
-stress (At work and at rest)
-stomping
-weight loss
-ear sores

Question 37

Management of biting flies in horses

Answer 37

-stable schedule and hygiene
-screens/mesh
-site selection for grazing and manure piles
-eliminate arthropod breeding sites (water)
-topical repellents

Question 38

Topical repellent treatments

Answer 38

-sprays, wipes, powders, back rubbers
*do not work for tabanids
*pesticides that cannot be used off label
*wound care to prevent myiasis