entomology and acarology

1. direct damage - mechanical, nutritive, toxic

2. indirect damage - vector/intermediate host of other pathogens

Acria:

• body unarticulated

• idiosoma (body)

• incision possible

Araneae

• Body articulated

• prosoma

• Heaps + thorax

• Opistoma (abdomen)

pic 7

Stigmata - holes for breathing

Coxae - Beginning part of the legs (Hip)

• belongs to the respiratory organ

• are located on the surface of the bpdy

• are opening of the tracheal system

• tracheas are branched channels for oxygen supply to the tissue

• have mo stigmata (breathing through integument)

• development: egg - larva - 2 nymphal stages -adult (total development 18-21d

• survial without hist: 2-3 weeks

• stationary-permanent parasites - they dont leave the host over all lifestages (24/7 on the host)

• differentiation of species by predilection site, infection animal species and morphology-> special regions for the different species

• infetsation direct and indirect (contaminated objects) - 2 animals really near, indirect - contaminated brushes

• zoonosis: sarcoptes: agent of pseudi scabies (Trugräube) in human

pic14

p 15

clinic:

• direct and indirect transmission

• herd disease

• latent carriers

• frequent occurence: winter, stabling, high animla stocking density

• located superficially or in deep skin layers

leading symptoms:

• intense itching

• dermatitis parasitaria (inflammation)

• hair loss

• lesions

Yes, living on the host, but could change. but theyalways need a host.

Haarbalgmilbe

• very common

• no itching

• clinic in young dogs (whole litter)

• use apathogenix (low level infestation/commensal

developement in D.canis:

• in hair follicles, thin-skinned body regions

• egg - L -N(2)- A

• transmission only from mother to puppies

• no transmission to other dogs by contact

• cigar-shaped

• 4 pairs of stubby legs

• short mouthparts

• hind body transversely grooved

• starke vermehrung

Dermanyssus gallinae (red bird mite)

• temporary ectoparasite - changes the host, attaches to skin gets some blood and alls of.

• development takes place in the environment of the host - only by night on the host. adults survive much longer without feeding

• suck blood

• infestation of host usually occours at night (30-90 min blood meal) = noctogenic parasite

• adults can survive without feeding at low temperatures for 5-9m

• Development -> 1week

• hunger periods - over 5 m

• females lay a few eggs daily in the hiding place

• hematogenous ectoparasite (N1, N2, A)

• anemia - blood loss, bad sleep & looses hair/fetters

• itching

• restlessness

• loss of feathers

• skin reaction

• anemia

• sudden deaths

• reduction of laying performance >10%

introduction of adult female mites with bees or drones

symptoms:

• malformations, brood damages, inability to fly, shortened life span

• collapse of the colony mostly in the 3rd/4th y of infestation

morphology:

• approx. 1mm in size

• transverse oval

• 4 pairs of logs (only visible from ventral side)

• Hairy margin

development: Egg - larva - nymph(s) - adult

• egg: lenth 200µm

• larva: 3 pairs of legs -1mm

• nymph: 4 pairs of legs, unfeed 1-2mm

• adult: 4 pairs of legs, unfed 2-10mm (fed up to 30mm in length)

• dorso-ventral flattened, oval, no distinct segmentation

• 2families - hard ticks (Schildzecke), soft ticks (Lederzecken)

spring and fall, bc need the right temperature ->

• dont find host in winter & dont like high temps.

• need high humidity to survive

where:

• adults: up to 150cm

• nymphs: up to 80cm

• larvae: up to 30cm

• humid habitats with thick, permanently moist detritus layer permanent shadding

• forst stand with much undergrowth and dense grass zone

• adjoining forst clearings

• overgrown gardens

• overgrown roadsides

• most of them not activley searching, they lurk

pheromone sensors on the first leg only

Soft ticks (argasidae) - argas refluxus

Hard ticks (ixodidae) - ixodes ricinus, ixodes hexagonus, ixodes canisuga,..

one-host tick life cycle: larva, nymph, adult, on one host

two-host tick lc: larva and nymph on first host, adult on next host

three-host tick lc: larva, nymph, adult each on new host

• sexual dimorphism

• surface covered by the scutum (Schild)

• Gnathosoma/capitulum of each stage dorsal visible

• duration of bloos uptake: 3-14d

• males of some species dont fed blood

• oviposition: up to 10’000 eggs over some weeks

• death of f - after oviposition, of m - after copulation

• during blood meal a female hard tick is able to take up the 120fold of its own weight

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How is it composit?

How does a tick bite? - pedipalps to feel and find the right position - dont get in the skin

chelicerae - cut the skin

Hypostom gets in the skin

do they search for a vena or can they bite everywhere - they surch everywhere by of the small arteriole

• complex sensory organ

• consists of the posterior capsule and the anterior pit

• pit with sensory setae at tarsus 1

• sensing pf humidity, temp., vibration and carbon dioxide

  • -> bc of that - waiting with first legs in V-shape

• three-host tick LC -> entire developemnt 3-6y. dependent on the host -> very warm year - everything going faster

• optimal conditions 17-20Grad, 80-90 % rel. humidity

• seasonal activity starts at 7-10grad

• central europe - start of activity: april; peak: may/june; activity during autum (when conditions are optimal): mid september to early november -> activity curve consists of 2 peaks

• males dont take up bloos or in less amounts

• vector function: borrelia burgdorferi sensu lato, babesio divergens,…

ixodes hexagonus: hedgehog tick

• 3 host LC

• Lives in dens/nests of its host -> adapted to microclimate

• besides hedgehog, different host, also humans rarely sheep, cattle and horses

• vector: B. burgdorferi sensu lato, Tick-borne encephalitis virus, Hepatozoon canis

ixodes canisuga: dog tick

• 3 host LC

• lives in the fox dens (Bau)

• attacks foxed, mustelids (mader), dogs

• maybe endemic in kennels (zwinger)

• vector: B burgdorferi sensu lato

• 3 host LC

• monotropic (<10% at differnt hosts than dogs) - really prefers dog

• entire development 3-12m

• originally in africa and mediterranean area, now nearly would wide distributed

• stable endemic center in heated rooms

• both sexes suck blood

• vector funciton: babesia canis vogeli, Ehrlichia canis, rickettia conorrii

d. marginatur (ornate sheep tick)

• 3 host tick LC

• Dry habitats (central, s, e Europe)

• in autum - fed femals enter diapause/break, oviposition during following spring (no eggs in winter)

• vector: Coxiella burnetii (Q fever), Babesia ovis,..)

d. reticulatur (ornate dog tick)

• 3 host tick LC

• Habitat: open ground, meadows, shrubbery, light wood land (central, s, e Europe)

• Vetor: Babesia canis canis, B. caballi, Borellia spp., C. burnetii, TBEV, Theileiria equi, Francisella tularensis

• 3 host LC

• humid, tight overgrown area

• in central europe insular distribution

• vector: babesia major, b. motasi, theileria spp.

• morphology: small, pale or reddish-brown tick

• at cattle-> udder (euter) and inner surface of limbs

number of legs? - ohnly 3 -> larva or insects

stigmata present? - no? -> not tick

genital pore present ? - not? -> to a adult tick

capitulum dorsal visible?

scutum present?

anal groove cranial or caudal to anus?

shape of basis capituli?

shape of pedipalps?

eyes present?

drawing of scutum?

when do the ticks infest the host? -> seasonal and depends on climate

1. activity of ticks

   • seasonal, dirunal (depending on climate)

2. appentence

   • host specific signals

   • pheromones (males!)

3. contact (need palps for right location to bite)

   • “sensillen” on chelicerae and palps -> identification of preferred attachment sites

4. attachment

   • scratch of skin, development of a feeding lesion

   • cement

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• development: Egg - 1 larva - often 2-8 nymphal stages - adult

• Morphology: often no sexual dimorphism - f are a little bigger

• integumant week sclerotized, leather like

• (Head) Capitulum only visible at the dorsal site during the larval stage

• Physiology: duration of blood uptake: larvae - 5-10d; nymphs and adulta: 15-120min; uptake of 0.3mL blood per adutl tick

• oviposition: 3-6 times, -80 eggs each

• development: egg- 1 larvae - 2-4 nymphal stages - adult; development time of one generation 3-8month up to 3 y

• preferred hosts: pigeons, poultry, free living birds

• habitat: attic, stable

• survival without host some years

• life span upt to 14y

• nymphs and adulta suck blood during night “hit and run”

• in germany no vector function

Morphology:

• capitulum (Chelicerae, hypostom, pedipalps, basis capituli)

• podosoma (coxae, haller’s organ)

• hairy, gut might be visible

• no stigmata

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1. anemia - e.g. by Argas reflexus

2. local inflammation reaction

3. secondary infections - other pathogens enter the body, bc open wound -e.g.s. aureus

4. vector - transmission of pathogens

5. metabolic stress in consequence of unspecific toxicosis - tick worry

6. paralysis - specific toxicosis induced by some foreign species - e.g. dermacentor andersoni, ixodes holocyclus

• gram - bacti

• causative agent of Lyme borrelioses (LB)

• Transmitted by ixodes ricinus species complex

• main vector in germany : i. ricinus

• reside in the midgut of an infected tick

• replicate in the midgut after tick begins to feed

• migration to the ticks salvary gland (16-24h)

• erythema migrans - appears after 3-30 days in 50-80%

• bacterial migration

  • caused by b. afzelii

• arthitis/arthrosis - joint pain -> b. burgdorferi ss

• neuroborreliosis -often as meningopolyneurits (Bannwarth syndrome) painful -> adiculitis -> b. garinii

• acrodermatitis chronica atrophicans -> skin rash -> b- afzelii

caput (big capitulum -head) - thorax - abdomen

3 pairs of legs, 1 paif of antenna, often wings, differently structured mouth parts

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• wingless

• 1-4mm in lenght

• dorsoventral flattened

• permanent stationary ectoparasite - on everything on the host

• broad head

• biting/chewing mouthparts

• “haarlinge” tarsus often with 1 claw

• “Federlinge” tarsus with a pair of claws

• Fed on skin/feather somponent and bacto exudate, some feed on blood (suborder ambylcera)

  • pigs, rabbits and humans dont have chewing lice!

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morphology:

• 2-6 mm in length

• dorsoventral flattened

• permanent stationary ectoparasite

• piercingly (=stechende) mouth parts

• intergrowth of tibia tarsus (=tibio-transaler - klammerapparat)

Entwicklung

• egg (nisse) - larve (1-3) - imago (4w)

• nutrition: blood - obligate

distribution:

• worldwide

• host specific, lice of animal cant be transmitted to humans

• cats and birds have no biting live

• cattle, pigs, goat, sheep,..

transmission:

• from sick to healthy animals (adults and larvae)

• survival time without host 3-7d

vector function:

• rickettsia maybe transmitted by lice. dead of russian war men

• biting/sucking lice of animals less of importance

• body louse of human may transmit: Rickettsia spp. and borrelia spp -> relapsing fever = Läuserückfallfieber

• 1-6mm

• lateral flattened body, often colored

• wingless

• 3. pair of legs transformed to anklebones

• holometabolous development: egg- larva (1-3) - pupa- imago, 2-20w

• - termporary, periodic ectoparasited

• not host specific - nest specific

• more than2000 species and subspecies worldwide, about 70 species in germans

• immediate blood uptake when flea infests the host - than regular (daily) blood meal

• obligate blood uptake (metabolism, oviposition, copulation)

• males and females suck blood

• duration blood meal: 2-10 min

• daily blood amount 10µl (-15 fold of body weight)

• life span on host up to 133d, if not removed by grooming

• oviposition 24-48h after first blood uptake

• mean of egg shedding/day = 27 -> 50 days

• 3 larval stages

• 1. stage larval - 2 mm

• 3. larva stage 4-5mm

• nutrition: flea feces = undigestes food (organic material) - from adults

• negative phototactic

• pupation of 3rd stage larva

• cocoon buildup, length 5 mm

• safest and resistant stage concerning environmental stress (UV, drought) -> perfect stage for survial under bad conditions

• can survive in cocoon over a period of one year

• after hatching - adults directly stats searching of hosts

• visual and thermal hatching stimuli

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spiny combs (stachelkämme / ctenidia)

->lower margin of the head

-> prothorax (1st thoracic segment)

• no combs ! naked flea

• one bristle under the eye

• E.S.1.0

• no legs

• head with antennae

• thorax : 3 segemnts

• abdomen: 9 segments

• hairy

• fleabite, papule with petechiae

• attack of huge flea numbers: eczema, excessive weight loss, anemia

• sensitization - flea allergy dermatitis (FAD)

• d. canium (dog tapeworm)

• hymenolepis nana; h. diminuta; H. citelli; H. microstoma (tapeworm of humans)

• Acanthocheilonema reconditum (former Dipetalonema reconditum)

• viruses: friend leukima virus; Hep. B virus; Polio virus

• rickettsia typhi murine typhus) other rickettsia spp.

• pasteurella spp.

• brucella spp. (e.g. B. melitensis; B. abortus; B. suis)

• Yersinia pestis (Pest)

• Bartonella henselae

antennae many membered (<6) + long (>head)

nema gr -thread; keras gr - horn

• only femal hematophagous

• temporal-periodic

• holometabolous

• defined larval habitats

Genera:

• anopheles

• culex

• aedes

morphology:

• 4-10mm, slim, long-legged

development:

• egg, larva (1-4), puppa, imago (10-25d)

• up to 7 generations each year

• oviposition on the water surface

• development of larvae and pupae in stationary water

• hosts: animals and humans

• larva have high o2 demand (atemfäden)

morphology: 2-6mm, dark colored, similar to flies short antennae “Buckelthorax”, width wings, short legs

developemnt: eggs-larva 1-6(9)- puppa- imago 6-8w

distribution: worldwide, wide distributed in central europe - march-nov.

hosts: cattle, horse, human

habitat: development only in straming water. flight distance in sprin about 5km upt o 13.

activitiy : in the afternoon (+++) and mornings (+), not at night

importance: simuliotoxicosis

blackflies as vectors:

• onchocera spp. in cattle

• onchocerca volvulus: river blindness in humans (africa, central and south america)

• protozoan, viruses - in the lab possible but not from epidemiological development

morphology: 1-4mm, arched (=gewölbt) thorax, flies light dark colored, wings spotted and hairy

developemnt: egg-larva1-4, puppa-imago

distribution: worldwide in all clime untile high mountains, in central europe flight time june-october

Habitat: terrestrial, semiaquatic and aquatic habitats, organic substances (compost),nuck (mist), feces, liquid manure (jauche), waste. Flight distance 500m, drift due to wind is possible.