Entomology Flashcards
- Chewing and blood-sucking lice
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
1) Biting/chewing lice:
- Amblycera (not in pig, rabbit, man); Menopon gallinae (bird)
- Ischnocera; Gonoides dissimilis (bird), Columbicola columbae (bird), Felicola subrostratus (fe), Trichodectes canis (ca), Bovicola bovis (bo), B. ovis (ov), Wennechiella equi (eq) Blood-sucking lice:
- Anopleura (not in cat, birds); Haematopinus suis (su), Linognathus vituli (bo), L. setosus (ca), L. stenopsis (goat), H. eurysternus (bo)
2) Wingless, 1-14 mm, female > male, dorsoventrally flattened, reduced or absent eyes, 9 abdominal segments, 6 pairs of spiracles (legs?).
CHEWING: Head broader than thorax, 3-5 segments in antenna, chewing mouthparts ventrally, in avian spp.: 2 tarsal claws
SUCKING: Head narrower than thorax, piercing mouthparts, 5-seg. antenna, 1 tarsal claw 3) Range of susceptible hosts, modes of infection
Host-specific, permanent ectoparasites, but exist in most mammals and also birds. Spread by contact/phoresy.
4) Epimorphosis = eggà3 or 5 nymphal stagesàAdult (insect) Stages separated by moults! (external skeleton is unable to grow)
Adult liceàLay eggs attached to hair shaftsàProduce 3 nymphal stages which
resemble adults. Each cycle takes roughly 1 month.
They life for 1-5 months. Survival off the host from 1 day to 2 weeks (long: chewing)
5) More appearances in winter (less sun, crowding, animals are indoors); scratching, intense grooming, fur loss, anaemia, weight loss, dermatitis, lameness (sheep L. pedalis)
6) No specific pathology; ectoparasite! Skin lesions, anaemia
7) Based on clinical signs, presence of nits (eggs), nymphs or adults.
8-10) Other questions
- Fleas
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
1) Species name of causative agents
Ctenocephalides canis (ca), C. felis (fe), Pulex irritans (hu), Spilopsyllus cuniculi (rabbit, fe, ca), Ceratophyllus gallinae (poultry, hu, pets), Xenopsylla cheopis (rat, hu), Tunga penetrans (hu), Echidnophaga gallinacean (fowl, mammals)
2) Morphology
1-6 mm, laterally flattened, wingless. Short, club-like antenna, piercing-sucking mouthparts. One or two combs (ctenidia) may be present; genal comb ventrally on head and pronotal comb anteriorly on thorax. 3 pairs of legs; 3rd pair strong and big for leaping. 10 abdominal segments.
3) Range of susceptible hosts, modes of infection
Non host-specific, permanent ectoparasites. Spread by indirect contact as the immature stages develop in the surroundings (non-parasitic)
4) Life cycle
(Holo)metamorphosis: Eggà3 larval stagesàpupaàAdult (insect)
Eggs are laid on host, but drop off and larvae dev. in environment. Larvae feed on debris and faeces of the adultsàspin cocoon encrusted with sand and pupate within.
5) Clinical signs
Restlessness, pruritus, intense grooming, anaemia. FAD: Flea allergic dermatitis, hypersensitivity reaction.
Dogs develop hot spots in lumbosacral region; moist dermatitis
Cats develop miliary dermatitis; redness, papule/vesicle formation, crusts
6) Pathology
7) Diagnosis
Clinical signs, presence of flea dirt, eggs. Flea dirt placed on moist tissueàRed, due to blood content. Presence of Dipylidium tapeworm, flea larvae in environment. Serology (ELISA) for animals with FAD.
8-10) Other questions
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Mosquitoes and blackflies Mosquitoes
1) Species name of causative agents Anopheles spp., Culex spp., Aedes spp.
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2) Morphology
2-10 mm, slender, long legs and wings. Females have piercing-sucking mouthparts, fleshy labium (does not enter), paired maxillae + mandibles, hypopharynx, labrum (enters). Males have reduced or absent maxillae + mandibles. Long, narrow antennae; pilose (hairy) for females, plumose (feathery) in males. Usually more than 11 segments.
Anopheles: Characteristically straight, acute angel with surface Culex, Aedes; Bent at thorax, whole body parallel with surface 3) Range of susceptible hosts, modes of infection
Wide range of hosts; temporary ectoparasites. Females suck blood for ovarian development. Not host-specific!
Female pierces skin with mouthparts, not painful
4) Life cycle
Eggs laid in stagnant water.
Anocepheles: Parallel to water surface
Culex, Aedes: At angle to surface, Culex also in groups (“floats”)
“Mummy-like” pupae: Comma-shaped, distinct cephalothorax and abdomen w/ resp. trumpets. Larvae are aquatic and do not feed. 4 larval stages, all free in water. Larvae gets oxygen both from water surface and from anal gills.
5) Clinical signs
Bites, irritation, stress, annoyance.
6) Pathology
7) Diagnosis
Presence of mosquitoes, still or stagnant waters nearby
8-10) Other questions
Most spp. Nocturnal or crepuscular, some diurnal. Only females suck blood. Eggs laid in stagnant waters.
Blackfly
1) Species name of causative agents Blackflies: Simulium columbaschense, S. damnosum
2) Morphology
Blackf.: 1,5-6 mm long, stout body w/ humped thorax, black/grey/brown. Short, stout, many- segmented antennae, short mouthparts, but with prominent maxillary palps. Eyes distinctly separated in female (dichoptic), closer in males (holoptic).
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3) Range of susceptible hosts, modes of infection
Wide range of hosts; temporary ectoparasites. Females suck blood for ovarian development. Not host-specific!
Blackf.: Female lacerates skin and sucks blood from pool that forms in woundàPain
4) Life cycle
Ovoid eggs laid on vegetation/stones near running water (prefers clean!).
6-9 larval stages in water rich in plankton, attached by hooks. Pupate within slipper-shaped cocoon, has long respiratory gills.
5) Clinical signs
Irritation, nuisance, stress over bites (swarms)àproduction losses.
Mass attacks in cattle can cause simulitoxicosis; generalised petechial haemorrhages on fine skin surfaces, oedema of larynx + abdominal wall (acute syndrome!)
Bites in ears of horses. Can cause anaemia in poultry.
6) Pathology
7) Diagnosis
Annoyed/stressed animals, bites, simulitoxicosis syndrome in cattle. Presence of running water, swarms.
8-10) Other questions
Most spp. Diurnal; active in morning and early evening. Only females suck blood; bites are painful as they create wounds to feed.
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Biting midges and sandflies Biting midge
1) Species name of causative agents
Biting midge. Suborder Nemotodaàfamily CeratopogonidaeàCulicoides spp.
2) Morphology
1.5-5 mm, humped thorax, mottled wings with rounded end, few veins. Balancing organ behind wings. Long antennae, short mouthparts. Female has longer antennae covered in short hairs which can carry pathogens, males have antennae covered in long, feathery hair.
3) Range of susceptible hosts, modes of infection Wide host range, non-specific. Non-permanent ectoparasite.
4) Life cycle
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Slender eggs laid in batches in moist places or very shallow waters. 4 larval stages, mummy like pupae. Larvae are small, with dark heads and serpentine swimming.
5) Clinical signs
Acute discomfort, irritation. Local irritation of horses: “sweet itch” on withers and base of tail. Allergic dermatitisàpapules, crusts, alopecia after detachment.
6) Pathology
7) Diagnosis
8-10) Other questions
Nocturnal or crepuscular, in high altitudes. Similar to or smaller than sandflies, but not hairy.
Sandflies
1) Species name of causative agents
Sand fly. Suborder Nematodaàfamily PsychididaeàPhlebotomus spp.
2) Morphology
5 mm, dull colour, hairy body with large black eyes. Very long antennae, short mouthparts, clearly visible maxillary palps. Wings covered in hair, narrow/sharp tip, veins in straight lines.
3) Range of susceptible hosts, modes of infection
Wide host range, non-permanent ectoparasite. Weak fliers, live in tropics/subtropics/Mediterranean areas.
4) Life cycle
Ovoid eggs laid in cracks/burrows/holes in ground. 4 larval stages resembling caterpillars (covered by bristles). Short-lived.
5) Clinical signs Bites, presence of sandflies.
6) Pathology Leishmaniosis.
7) Diagnosis
8-10) Other questions
Only females suck blood, both sexes also feed on plant juices.
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Horse- and deerflies
1) Species name of causative agents
“Intermediate” between Nematocera and Brachycera, but officially in suborder Brachycera. àFamily Tabanidae
Tabanus spp.
Chrysops spp.
Haematopota spp.
2) Morphology
General: Large (up to 2,5 cm, wing span 6 cm!), bean-shaped head, short antenna w/ 3 segments, short mouthparts (males have no mandibles), colourful eyes while alive. Slashing-sponging mouthparts on female (? Brachycera suborder)
Tabanus: Largest, antennae is shorter than head. Clear or brownish wings.
Chrysops: “Spotted” appearance, medium size. Antennae minimum the same length as head, often with dark bands across wings.
Haematopota: Small, antennae longer than head. Head is wider than thorax, mottled wings.
3) Range of susceptible hosts, modes of infection
No host specificity, but prefers ruminants, horses, mammals. Active during hot, sunny days, very good flyers.
Females feed on blood every 3-4 days. Some species feed on plants only!
4) Life cycle
Cigar-shaped eggs laid in batchesà7-11 carnivorous larval stages (stage 1 and 2 does not feed)àmummy-like pupae with distinct head, thorax, abdomen.
5) Clinical signs
Painful, deep bitesàstress, nuisanceàproduction losses.
Blood loss (can suck 4 times their own body weight from lacerated vessels!) Result in woundsàattracts fliesàMyiasis!
6) Pathology
7) Diagnosis
8-10) Other questions
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Tsetse flies
1) Species name of causative agents
Family GlossinidaeàGlossina morsitans, G. pallidipes Form three groups depending on the habitat:
Fusca – forests
Palpalis – River areas, gallery forests Morsitans – Savannah
2) Morphology
6-15 mm, yellow/dark brown colour. Long, rigid, forward-projecting proboscis; no maxillae or mandibles. Palps are equal to proboscis in length, forming a sheath (seen as long piercing organ). Antennae w/ big, feathered arista. Hatchet cell in wings! Wings are parallel, stacked.
3) Range of susceptible hosts, modes of infection
Both males and females feed on blood, no host specificity. Occur only in sub-Saharan Africa.
4) Life cycle
Females give birth to one fully grown 3rd stage larvae; viviparous!
à8-10 mm, whitish, segmented with dark lobes at the end.
Larvae burrows into soilàDark, barrel-shaped pupaeàEmerges to surface after approx.. 1 month. Larvae never feeds until adult!
5) Clinical signs Painful bites, irritation.
6) Pathology
7) Diagnosis
8-10) Other questions
Diurnal parasites, both genders suck blood!
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Forestflies
1) Species name of causative agents Family Hippoboscidae
àHippobosca equina – Horse louse fly àLipoptena cervi – Deer ked àMelophagus ovinus – Sheep ked
2) Morphology
Dorsoventrally flattened, reddish brown. Feeds on blood so has proboscis.
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H. equina: 1 cm, wings with yellow spots
L. cervi: Loses its wings after settling on host
M. ovinus: 0.5 cm, winglessàWounds on skin of sheep
3) Range of susceptible hosts, modes of infection Horse, deer, sheep
4) Life cycle
Females are viviparous; lay fully grown larvae. Some lose wings after settling on host.
5) Clinical signs
Annoyance, anaemia, fleece damage, dermatitis, wounds.
6) Pathology
7) Diagnosis
8-10) Other questions
Tolerant for compression! Swats from tails survival mechanism?
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- The house fly and the stable fly House fly
1) Species name of causative agents Family MuscidaeàMusca domestica
2) Morphology
Larva: Inner cephalopharyngeal skeleton in first segments, posterior respiratory spiracles Adults: ø piercing organs, yellow spots, short antenna with hair at base, licking mouth-parts, arista on the third antennal segment.
7-8 mm long, lapping mouthparts. Synanthropic (associated with man), secretophagous (preoral dogestion)
3) Range of susceptible hosts, modes of infection
Survive “anywhere”, mainly endophilic, but originate from boarsàpreference for swine faeces.
4) Life cycle
In decaying plant or animal tissues.
Banana-shaped, light eggsà12-segmented larva, 3 stages (last is 12 mm) with oral hooksà Barrel-shaped puparium: Starts off light, then becomes reddish brown.
Extremely productive; can have 10-30 generations per year!
5) Clinical signs
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Annoyance, can exaggerate wounds (feed in them) 6) Pathology
Carrier of more than 100 pathogens! 7) Diagnosis
8-10) Other questions
Stable fly
1) Species name of causative agents Family MuscidaeàStomoxys calcitrans
2) Morphology
Larva: Inner cephalopharyngeal skeleton in first segments, posterior respiratory spiracles 6-7 mm with long, forward-projecting proboscis, bigger than palps. Long piercing-sucking mouthpars, no maxillae or mandibles. Club-shaped antennae. Grey/brown markings, brown pupae.
3) Range of susceptible hosts, modes of infection
Found in stables (endophilic), attacks any animal! Both sexes feed on blood 1-2 times daily. Searches for wounds, but prefers shaded areasàbelly/legs. Usually sits with head in upward direction.
4) Life cycle
They prefer decaying, moist, fermented materials and never breed in fresh dungàimportant to keep area clean!
Eggà3 larval stages (slender w/ oral hooks)àBarrel-shaped pupa
5) Clinical signs
Great source of annoyance (anaemia in very severe cases?)
Carry pathogens! Viruses and ectoparasitesàMechanical vectors
6) Pathology
7) Diagnosis
8-10) Other questions
Long piercing-sucking mouthparts, unusual in muscoid flies! BOTH sexes drink blood. Usually diurnal. Synanthropic and endophilic (indoors)
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Important fly species of grazing animals
Musca automnalis – face fly
Family Muscidae
5-7 mm, resemble house fly but exophilic (live outdoors)
àlapping mouthparts, yellow spots, antenna w/ 3 seg. and arista at base. Male with eyes close together, females eyes set wider apart.
Source of annoyance, mechanical and biological vector!
- Moraxella bovis: pink-eye in cattle.
Feed on secretions around eyes, nose, mouth and wounds – liquids containing protein Settle temporarily on the animals, usually around cattle.
Eggà3 larval stagesàPupa (remains light!)
Haematobia irritans – horn fly
Family Muscidae
4 mm, shorter proboscis almost equal in length to palps, still long piercing organ. Looks similar to stable fly, but with longer palps. Yellowish abdomen.
Eggs are laid in fresh manureà3 larval stagesàPupa
Cause intense irritation, blood loss, are biological vectors!
Exophilic (lives outside), BOTH sexes feed on blood 20-30 (!) times daily.
Usually remain on host, especially around horns, back and sides of cattle. Doesn’t mind sunlight. Usually sit with their heads pointing downwards.
Muscina stabulans – false stable fly
Family Muscidae
Procreate/feed in old manure, decaying carcasses No piercing organ
Exophilic (?), guessing similar morph. to stable fly? Eggsà3 larval stagesàpupa
Hydrotea irritans – head fly
Small, develop in wet soil around meadows (exophilic)
1st stage larvae never leaves the egg, 2nd stage feed on dung Brownish, with iridescent wings
Ø piercing organ, doesn’t bite
Vector for pyogenic skin diseases!
Licking mouthparts, likes liquids.
Settles around eyes, udder (anal opening) à Can carry Staph./Strep. à Mastitis??
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Calliphorid and sarcophagid flies, traumatic myiasis Callophorid flies - Blowflies
1) Species name of causative agents
Order DipteraàDivision CyclorrhaphaàFamily Calliphoridae àLucilia, Cochliomyia spp.
2) Morphology
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Up to 1 cm long, shiny, brilliant metallic blue/green/bronze sheen of the body. 3) Range of susceptible hosts, modes of infection
Lucilia sericata: Mainly in Europe, also in southern hemisphere
Lucilia cuprina: In southern hemisphere: Australia, New Zealand, South-Africa
Eggs are laid into decaying organic matter or skin/wounds (facultative! Scavenger spp.) àImportant to remove any carcasses!
Cochliomyia hominivorax: New worldàLatin and South America
Obligate parasite of warm-blooded animals (domestic + wildlife), also attacks humans!
4) Life cycle
Usually in dark buildings, flower pots etc.
Lucilia: Facultative flies!àEggs are laid in decaying organic matter or wounds
- Maggots with anterior + posterior spinacles, cephalophalyngeal skeleton.
Third stage larvae are 10-14 mm, smooth, with closed peritreme. Pupation in the ground.
5) Clinical signs
Visible eggs/larva on skin/in wounds. Swellings, holes where they bury.
6) Pathology
Dermatophilosis, fleece rot, dermatitis (pseudomonas inf.)
7) Diagnosis
8-10) Other questions
Sarcophagid flies - Fleshflies
1) Species name of causative agents
Family SarcophagidaeàWohlfahrtia spp. (obligate), sarcophaga spp. (facultative) 2) Morphology
12-15 mm, grey-black, dull body (non-metallic), abdomen with spots. Similar to stable fly, but ø piercing organ and NEVER feed on blood.
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3) Range of susceptible hosts, modes of infection
Mammals, including humans. Adults land on hostàLays larvaeàLarvae buries
4) Life cycle
Females lay first stage larvae (larviparous!), they are obligate parasites. Third stage larvae/maggot has spines, buries in host skin. Posterior spiracles are sunken deeply into round cavity, peritreme is open for air supply. Block air supplyàmaggot crawls out!
5) Clinical signs
Animals are anorexic, dull, standing away from the flock. Production loss, ruined hides and fleeces. Reproductive problems, lameness.
Marked deformity after recoveryàFibrosis, scars (e.g. perineum, vulva)
6) Pathology
Larvae bury deep into host tissueàDamage by oral hooks, spines, proteolytic enzymes
- Liquefaction, necrosis, haemorrhage - Wounds, odour attracts further flies - Septicaemia à death!
7) Diagnosis
8-10) Other questions
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Hypodermosis
= Warble flies
1) Species name of causative agents
Order DipteraàSuborder BrachyceraàDivision CyclorrhaphaàFamily Oestridaeà Subfamily Hypodermatinae: Hypoderma bovis, H. lineatum (cattle!)
2) Morphology
Adults: 1,5 cm, bee-like with yellow/orange hairs, no stinger or functional mouthparts! Larvae: 2-3 cm, stout (warbles/grubs), whitish, segments with short spines.
3) Range of susceptible hosts, modes of infection Females land on cattle, attach eggs to fur
4) Life cycle
Eggs are attached to hairs on upper or lower part of the body (gluteal region, limbs).
3 larval stages: Hatchingà1st larva penetrates the skin and migrates to spinal canal (H. bovis) or to diaphragm, oesophagus (H. lineatum). This migration takes around 6 months.
- 1st moult epidurally (H. bovis) or submucosally (H. lineatum)
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- 2nd moult in subcutis of the backàRemain here for 3 months
- 3rd stage larvae is darker, makes perforation in skin for air supplyà“holes”
- After 6-9 months the larvae emerge and falls to the ground to pupate.
5) Clinical signs
H. bovis causes panicking (during egg laying), paraplegia H. lineatum causes faulty regurgitation
Anaphylaxis, production losses
6) Pathology
Greenish, gelatinous substance in the muscles (“butcher’s jelly”) Hide damage, holes
7) Diagnosis
Eggs on the hairs, swellings on the back, serology (ELISA)
8-10) Other questions
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Gasterophilosis
= Botflies
1) Species name of causative agents
Subfamily Gasterophilinae àIntestinalis (most common) à Nasalis
à Haemorrhoidalis
à Pecorum
2) Morphology
Adults: 1-2 cm, resemble honey bee but slimmer than Hypoderma (brown, hairy), reduced, non-functional mouthparts (makes them hard to catch – does not eat!)
- Females ovipositor is curved under the abdomen
3rd stage larvae: < 2 cm, 2 big oral hooks, 1-2 rows of very strong spines per segment. Red pigment to trap Oxygen.
3) Range of susceptible hosts, modes of infection Found in horses, equids. Not in ruminants!
4) Life cycle
Eggs are laid on hair (or Pecorum: on pasture)
- Intestinalis: shoulder region, Nasalis, Haemorrhoidalis: around the mouth
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àafter hatching the 1st stage larva enters mouthàPenetrates mucosa/tongue and moultà migrate to stomach, attach (position varies by species) and moults againàDevelop for 10-12 months while feeding on tissue exudatesàmature larvae detach, pass in faeces (Haemorr. re- attaches again in the rectum)àPupate in soil
5) Clinical signs Usually absent.
Occasionally toxic anaemia, rectal irritation, digestive problems due to narrowed GIT Migration of larvae in human skinàCreeping eruption
6) Pathology
Stomatitis, ulcers with hyperplastic edge on tongue, in stomach.
7) Diagnosis
Demonstration of eggs on hairs, larvae (in mouth, pharynx, stomach, faeces)
8-10) Other questions
Adults are short-lived and non-feeding! Larvae always found in GIT
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Oestrosis
= Sheep nasal botfly
1) Species name of causative agents
Subfamily OestrinaeàOestrus ovis 2) Morphology
Adults: 1 cm, with brown hairs, big head with small (non-functional?) mouthparts and widely separated eyes. Small black spots, esp. on thorax.
3rd larval stage: Up to 3 cm, dark traverse band dorsally on each segment, spines ventrally. Never red in colour, usually white/brown
3) Range of susceptible hosts, modes of infection Small ruminants, females lay larva at nostrils.
4) Life cycle
Viviparous female lays larva at nostrilsàLarva migrates through the nasal passages and moultàEnters frontal sinuses where they moult againàfeed on mucous and epithelial cells àMature larvae return to nostrilsàExpelled by sneezing after 9-10 months (shorter depending on the time of year; as little as 1 month in summer!)àPupate in soil
5) Clinical signs Seldom cause any symptoms.
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If they destroy ethmoid boneàbacterial inflammationàencephalitisà“false gid” = CNS symptomsàdeath (rare)
Less harmful as they feed on mucous and epithelial cells, not blood.
Heavy infection: nasal discharge, sneezing, nose-rubbing, unthriftiness, circling and uncoordination (“false gid”), weight loss.
Ophtalmomyiasis of dog and human! 6) Pathology
Purulent ethmoiditis (cerebral involvement) in case of larval death in sinuses; pharyngitis, secondary bacterial invasion.
7) Diagnosis
Typical signs, expelled larvae.
Postmortem: Sawing skull openàFind larvae (BUT they are photophobic: Hide from light!)
8-10) Other questions
Mange
Dermatitis with epidermal hyperplasia, scaling, crust and scab formation. Pruritusàself-rubbing and alopecia.
Papule and vesicle formation leads to thickened, wrinkled skin.
Secondary bacterial inf. may aggravate conditionàCan become fatal if untreated
Mange diagnostics
Anamnesis: Contact with other animals, severe and sudden pruritus
Deep skin scrape: Detects burrowing mites. Scrape perpendicularly to skin surface until blood appears.
Superficial skin scrape: Detects non-burrowing mites. Scrape from edge of a lesion into ointment or vial.
Collection of cerumen of the ear by swabbing of the ear canalàexamination over dark surface, or by microscope.
Microscopic examination: Light + warmth causes mites to move.
Kerationus substance of skin can be dissolved in 10% sodium or potassium hydroxide, or boiled and centrifugedàExamine sediment.
Negative skin scrapes are inconclusive!
àSkin biopsy, new scrapes, trial therapy may help diagnosis.
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ELISA available for mange in dogs.
Zoonotic? Any mammalian mange can settle temporarily on humansàGloves!
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Mange of horse and cattle
Horse
Sarcoptes scabiei var. EquiàSarcoptic mange
Suborder Astigmataàfamily SarcoptidaeàSarcoptes scabiei
o No respiratory openings, cutaneous respiration
Burrowing mite, lives inside the skin. Female burrows tunnels for egg-laying and larval development.
Permanent ectoparasites. Survives off the host only for a few days.
Very strict host-specifity!
Morphology:
o Round body, up to 0,4 mm (female > male)
o Striation, ridges, triangular scales on dorsal surface (“fingerprint”) o Short legs, 3rd and 4th pairs of females do not project beyond body o Pretarsus with long, unsegmented pedicel, small ambulacrum
o Terminal anal opening
Psoroptes spp.àPsoroptic mange
Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Piercing mouthpart, feeds on tissue fluids.
Survives off the host for maximum 2-3 weeks
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Long, 3-segmented pedicel (foot stalk)
Development takes approx.. 2 weeks, 2 nymphal stages
P. cuniculiàOtitis externa (head-shaking) P. ovisàDensely coated areas
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Parasitology final Yvonne Lynum, Nora A. Valen, Guro Ølmheim 2019
Chorioptes bovisàChorioptic mange, typically on cold-blooded/heavy horses; lower part of hind legs.
Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Chewing mouthpart, feeds on epidermal dermis.
Survives off the host for maximum 2-3 weeks
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Short, unsegmented pedicel (foot stalk)
Development takes approx.. 2 weeks, 2 nymphal stages
Cattle
Sarcoptes scabiei var. bovisàSarcoptic mange on short-haired body parts (often young) Suborder Astigmataàfamily SarcoptidaeàSarcoptes scabiei
o No respiratory openings, cutaneous respiration
Burrowing mite, lives inside the skin. Female burrows tunnels for egg-laying and larval development.
Permanent ectoparasites. Survives off the host only for a few days.
Very strict host-specifity!
Morphology:
o Round body, up to 0,4 mm (female > male)
o Striation, ridges, triangular scales on dorsal surface (“fingerprint”) o Short legs, 3rd and 4th pairs of females do not project beyond body o Pretarsus with long, unsegmented pedicel, small ambulacrum
o Terminal anal opening
P. ovisàPsoroptic mange on long-haired body parts (not permanent) Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Piercing mouthpart, feeds on tissue fluids.
Survives off the host for maximum 2-3 weeks
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Parasitology final Yvonne Lynum, Nora A. Valen, Guro Ølmheim 2019
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Long, 3-segmented pedicel (foot stalk)
Development takes approx.. 2 weeks
C. ovisàChorioptic mange on lower legs, scrotum, perineum, tail-base (specific for cattle) Order AcariformesàSuborder Astigmataàfamily Psoroptidae
Live and develop on mammalian skin surface: Non-burrowing mite
Chewing mouthpart, feeds on epidermal dermis.
Survives off the host for maximum 2-3 weeks Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Short, unsegmented pedicel (foot stalk)
Development takes approx.. 2 weeks, 2 nymphal stages
1) Species name of causative agents
2) Morphology
3) Range of susceptible hosts, modes of infection
4) Life cycle
5) Clinical signs
6) Pathology Not characteristic
7) Diagnosis
8-10) Other questions
- Mange of sheep, goat and pig
Sheep and goat
Sarcoptes scabiei var. Ovis/CapraeàSarcoptic mange (short hair) Suborder Astigmataàfamily SarcoptidaeàSarcoptes scabiei
o No respiratory openings, cutaneous respiration
Burrowing mite, lives inside the skin. Female burrows tunnels for egg-laying and larval development.
Permanent ectoparasites. Survives off the host only for a few days.
Very strict host-specifity!
Morphology:
o Round body, up to 0,4 mm (female > male)
o Striation, ridges, triangular scales on dorsal surface (“fingerprint”) o Short legs, 3rd and 4th pairs of females do not project beyond body o Pretarsus with long, unsegmented pedicel, small ambulacrum
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Parasitology final Yvonne Lynum, Nora A. Valen, Guro Ølmheim 2019 o Terminal anal opening
P. OvisàPsoroptic mange (long hair: Dorsally on neck, base of tail)
Specifically in sheep?
Causes uneven wool (tags projecting from fleece), palm-size lesions developing over 2-6 weeks, becomes dry in the centre.
Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Piercing mouthpart, feeds on tissue fluids.
Survives off the host for maximum 2-3 weeks
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Long, 3-segmented pedicel (foot stalk)
Development takes approx.. 2 weeks
P. cuniculiàEar of goat (spread to head, neck and body)
Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Piercing mouthpart, feeds on tissue fluids.
Survives off the host for maximum 2-3 weeks
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Long, 3-segmented pedicel (foot stalk)
Development takes approx.. 2 weeks
C. bovisàChorioptic mange (lower legs, scrotum)
Order AcariformesàSuborder Astigmataàfamily Psoroptidae Live and develop on mammalian skin surface: Non-burrowing mite Chewing mouthpart, feeds on epidermal dermis.
Survives off the host for maximum 2-3 weeks
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Parasitology final Yvonne Lynum, Nora A. Valen, Guro Ølmheim 2019
Morphology
o Oval body, up to 0,8 mm (female > male) o Long legs; Project beyond body
o Males have one pair of genital suckers oo o Short, unsegmented pedicel (foot stalk)
Development takes approx.. 2 weeks, 2 nymphal stages Prevention by dipping once a year. Often latent, symptomless.
Pig
Sarcoptes scabiei var. suisàSarcoptic mange
Acute (at 3-4 weeks of age) and chronic (sow, boar) forms.
Spreads from ears to most of the body.
Involved areas develop hyper- and paraketosisàReduced growth, feed-conversion.
Suborder Astigmataàfamily SarcoptidaeàSarcoptes scabiei o No respiratory openings, cutaneous respiration
Burrowing mite, lives inside the skin. Female burrows tunnels for egg-laying and larval development.
Permanent ectoparasites. Survives off the host only for a few days.
Very strict host-specifity!
Morphology:
o Round body, up to 0,4 mm (female > male)
o Striation, ridges, triangular scales on dorsal surface (“fingerprint”) o Short legs, 3rd and 4th pairs of females do not project beyond body o Pretarsus with long, unsegmented pedicel, small ambulacrum
o Terminal anal opening
Develop in moulting pockets for approx. 3 weeks
