Final Exam: Pasture Flies Flashcards
what species of fly has the greatest estimated control cost for cattle production cost
horn fly
higher flies body parts
3 antennal segments
major types of higher flies
blood feeders; liquid feeders (spongers); internal parasites (bots, grubs); wound maggots
puparium
pupa of flies
larvae
maggots- larvae without head capsule-internal plates only
moise or semi-aquatic habitats, decaying organic matter, feces, carrion, wounds
horn and face flies are known as
pasture flies
horn flys are what type of blood feeders?
obligate; piercing/sucking with a painful bite
most important pest of pastured/rangeland cattle
horn fly
what sex of horn fly feeds on blood
males and females - ~30 blod meals/fly/day
main horn fly feeding sites
udder; back; belly
horn fly life cycle
cow–>manure–>cow
breeding site of horn fly
fresh cow manure
horn fly spring emergence from pupa is when
march-may; as daylength gets longer adults will come out (diapause until then)
horn flys need what in cow manure to survive?
bacteria
how often do horn flies stay on host?
95%+ life spent on host animal; off host to change host or lay eggs; disperse at night
reasons why horn flies are somewhat easy to treat
don’t have to treat all animals because they move from animal to animal
breed only in fresh cow manure so you can treat manure
IGR
insect growth regulators —> manure treatment
past (1892) horn fly control in KY
pyrethrins powders; finely ground tabacco; whale oil
horn fly control systems
dust bag; ear tag; pour on; iGR mineral; supplement; oiler; spray; walk thru fly trap
vaccine for horn fly control
flyvax; cause blood to coagulate faster
horn fly expectations on #’s per animal
~100 per animal in acceptable
face flys are what kind of feeders
liquid
face fly hosts
cattle, horses
face fly life cycle
face–> manure
needs fresh manure
eggs–>pupae–> larvae–> adults
face fly breeding sites
fresh cow manure - bacteria
pupate in soil beneath manure
need moisture; rainfall important
where do face flies spend winter and in what stage
adults; stay in protective places hidden; reproductive diapause
how much time do face flies spend on hosts
~5% of time on hosts; usually stay near host - rest on trees and vegetation and structures at night and most of day
how do face flies feed?
sponging mouthparts with microscopic rasping teeth - causes tear flow from eyes
mostly female
protein from mucus, saliva, and tears
life span of face flies
10 days
major impacts of face flies
annoyance; shift to night grazing; vector of pinkeye and eyeworm
pinkeye
direct contact transmission from wings and legs of face flies up to 3 days after exposure
pinkeye symptoms
swelling and redness of eyes, excess tearing, occasional severe ulceration, blindness
pinkeye impact
2nd to scours as most prevalent condition affecting born unweaned calves >3wks old and breeding beef females
***factors affecting pinkeye
- eye irritation - excessive UV light, face fly, plant material, and dust
- lack of pigmentation around eye allows increased UV radiation - inflammation, infection
- Flies - irritant and vector
- plant material - grasses, pollen, brush - mechanical irritants
managing pinkeye
fly control, vegetation control, shade, immunization, select for eyelid pigment, hay feeding management
eyeworms transmission
nematode larvae in eye secretions picked up by feeding flies
infective larvae deposited about 1 wk later
treating face flies
if 10+ flies/face
dust bags, ear tags
why is face fly control so difficult?
increasing population during season; short time on animal; re-infestation from nearby herd
horn fly vs face fly: breeding site
Horn: very fresh cow manure - 10 min
Face: fresh cow manure - 1-2 hrs
horn fly vs face fly: time ON animals
Horn: 95%+
Face: 5%
horn fly vs face fly: % population on animals
Horn: 95
Face: 20
horn fly vs face fly: migration distance
Horn: 1-5 mi
Face: ~7 mi
horn fly vs face fly: adult food
Horn: blood
face: tears, mucous, wound ooze
horn fly vs face fly: impact
Horn: defensive behavior, stress, lower weaning weights, low milk production, hide damage
face: pinkeye, treatment time and effort
horn fly vs face fly: disease potential
Horn: blood BORNE ANAPLASMOSIS, summer mastitis
face: pinkeye (3-4d) eyeworm (NE)
horn fly vs face fly: treatment guideline
Horn: ~10 per head
Face: ~ 100/side beef 50/side dairy
horn fly vs face fly: winter
Horn: Pupa under co manure
Face: adult in hibernaculum, reproductive diapause
