Parasites in exotic species

What is Cheyletiella parasitovorax?

Non-burrowing mite

Rabbits

Life cycle 14-21 days

Waisted mite with hooked palms and combed tips to legs

Visible with the naked eye “Walking Dandruff”

Often carried sub-clinically

Zoonotic potential

Can infest other species

Clinical signs
• Dorsal scaling, crusting
• Variable pruritus
• Partial alopecia

What is Psoroptes cuniculi?

Non-burrowing mites

Rabbits

3 Week life cycle

Visible with naked eye

Oval shaped mites

Transmission via infected rabbits or fomites

One of the most common causes of rabbit dermatoses

Rabbits may develop immunity

Clinical signs
• Pruritic otitis externa
• Thick pinnal crusts and ulceration
• Neurological signs w/ otitis media/TM perforation

What are the types of fleas found in rabbits?

Spilopsyllus cuniculi
• Rabbit flea
• Most commonly seen on wild rabbits
• Important vector for myxomatosis

Ctenocephalides felis/canis
Cat/Dog flea more commonly found on pets
Clinical signs:
• Pruritus, poor coat
• May be clinically normal
Treatment of rabbit, in contacts and environment

What is Myiasis in Rabbits?

Fly strike- usually Lucilia app. (Greenbottles)

Summer months

Usually primary with underlying cause

Eggs can hatch within 12hrs to L1 (non pathogenic)

Within 3 days L1 → L2 and L3, cause tissue damage

Larval Cuterebra spp can cause
• subcutaneous infections
• aberrant intracranial migration → neurological signs

What are common nematodes in rabbits?

Passalurus ambiguus

Oxyurid worm ‘pinworm’
Found in caecum and large intestine More common in wild rabbit populations Usually non-pathogenic

Obeliscoides cuniculi

Stomach worm - occasionally found in wild rabbits
Not reported in pet rabbits in UK

Trichostrongylus retortaeformis

Intestinal worm- Europe and Australia- not USA

What causes coccidiosis in Rabbits?

Protozoan parasites

Intestinal coccidiosis:

Various including E.manga and E.irresidua

Clinical signs variable:

. Weight loss, abdominal distension, diarrhoea, anorexia, depression

Hepatic coccidiosis:

Eimeria steidae

Epithelial cells of bile ducts

Clinical signs:

.Weight loss, ascites, jaundice, diarrhoea, hepatomegaly

What is Encephalitozoon cuniculi?

Obligate intracellular protozoal parasite

Widespread in rabbit population

Zoonotic:
. Potentially life-threatening in immunocompromised humans

Infective spores shed in urine

Infection via ingestion of spores or vertical transmission

Parasite primarily attacks CNS, kidney and eye

What type of mites are commonly found in guinea pigs?

Trixicarus caviae

Sarcoptid mite

10-14 day life cycle

Asymptomatic carriers common

Lesions usually dorsal neck and thorax may become generalised

Clinical signs:

Intense pruritus

Self trauma

Seizures

Foetal resorption in pregnancy

Zoonotic potential

What lice are common in guinea pigs?

Gliricola porcelli and Gyropus ovalis

Common

Biting lice

Mild dermatitis

Heavy infestations can lead to alopecia and crusty lesions

Trimenopon hispidum

Rare biting louse hat W

What are common ectoparasites in myomorphs?

Fur mites in rats and mice
• Radfordia ensifera (rats), Myocoptes musculinus, Myobia musculi, Radfordia affinis (mice)
• Ulcerative, crusty lesions over head and shoulders
• Classic patterns of distribution for different mites

Notoedres muris – burrowing mite
• Pruritic, warty papular lesions on extremities
• Parasitic otitis in mice
• Diagnosis by skin biopsy or clinical response to tx

Demodex
• Immunosuppressed hamsters, concurrent disease eg cutaneous lymphoma
• Seizures

Fleas rare – usually from household contacts

What are common endoparasites in myomorphs?

Oxyurid Pinworms
• Syphacia obvelata
• Some other spp not associated with clinical disease but affect growth
• Diagnosis on tape strip microscopy S. obvelata or faecal flotation microscopy (banana shaped eggs)
• Heavy infections can lead to rectal prolapse

Cestodes (Rodentolepis nana & Hymenolepis diminuta)
• Rat is definitive host but can infect mice
• Disease only with heavy burdens
! Zoonotic potential
• Hymenolepis nana most significant endoparasite of hamsters (dwarf tapeworm)

Protozoa
• Pathogenic flagellates Giardia muris & Spironucleus muris
• Eimeria

What are common endoparasites in ferrets?

Endoparasites are rare in ferrets

Protozoa:

Coccidia- Isopora and Eimeria spp, generally subclinical except shelter and breeding groups, GI signs

Cryptosporidium spp- Raw feeding a risk factor, usually self limiting in healthy individuals, signs of gastroenteritis, zoonotic potential!

Giardia- uncommon

What are common mites in ferrets?

Sarcoptes scabei
• Direct contact with other animals
• Generalised alopecia and pruritus
• Localised lesions of toes and feet
! Zoonotic potential

Otodectes cyanotis
• Ear mite (as per cats and dogs)
• Can be asymptomatic
• Severe crusting and pruritus → secondary bacterial otitis

Lynxacarus mustelae (rare)
• Fur mite
• Ulcerative facial lesions in kits, immunosuppressed individuals

Demodex spp (rare)
• Secondary?

What are common fleas and ticks in ferrets?

Fleas
• Ctenocephalides felis, C. canis, Pulex irritans
• Mild to intense pruritus – usually around neck
• Flea bite hypersensitivity reported

Ticks
• Ixodes ricinus
• Common in hunting and stray ferrets
• Rare in pet ferrets
• Lyme disease not reported
• Can lead to anaemia in heavy burdens

What are the most common types of ectoparasites in reptiles?

Mites

What is Ophionyssis natricis?

Affects all reptilian taxa

Red, brown, black or grey mites

7-16 day life cycle

May be observes on the reptile or in the environment

Can occasionally affect humans

Clinical signs:

. Behaviour changes

. Dysecdysis

. Dehydration

. Anaemia

How common is coccidia in reptiles?

Common

Agamids, Chameleons, Geckos are most represented

Eimeria, Isospora, Sarcocystis, Caryospora spp

Direct life cycle- poor hygiene/overcrowding implicated

Clinical signs (usually GI):

. Often sub-clinical

. Enteritis, anorexia, lethargy, weight loss, prolapse, death

What are common cryptosporidium for reptiles?

Common cause of gastrointestinal disease

C. serpentes, C. saurophilum

Faeco-oral transmission

Treatment not effective

Clinical Signs:
• Sporadic regurgitation of typically mucus covered prey (snakes)
• Gastric mass may be palpable
• Diarrhoea (lizards) with mucosal thickening of intestine
• Weight loss, debilitation, death

What are common flagellates in reptiles?

Common finding

Trichomonads, Giardia, Hexamita spp

Intestinal disease

High numbers associated with anorexia, weight loss and diarrhoea

Desiccate and die quickly

What is Entamoeba invades?

Protozoa

Commensal in herbivorous reptiles

Invade intestinal mucosa and cause disease in carnivorous reptile (snakes)

Mixed collection is a major risk factor

Direct lifecycle- transmission through direct contact with cyst form

Clinical signs:

Anorexia, Weight loss, regurgitation, constipation, diarrhoea, neurological signs, death

What are common nematodes in reptiles?

How are cestodes found in reptiles?

Found in all orders of reptiles

May be definitive, paratenic or intermediate host

Many spp non pathogenic

May see proglottids around cloaca

Ova in faeces

How are trematodes found in reptiles?

Wild caught reptiles esp aquatic

Most require aquatic molluscs, fish or amphibians as intermediate hosts

Rare in captive reptiles

Generally non pathogenic

Spirorchiids pathogenic in turtles
• Live in heart and blood vessels
• Can cause ischaemia, necrosis and organ failure

What are common parasites in wildlife?

Species specific examples
• Lungworm complex in Hedgehogs
• Acariasis/Ticks in Hedgehogs
• Trichomoniasis in Columbiformes and Raptors
• Sarcoptic mange in Foxes
• Hippoboscids in wild birds

Generally an indication of debilitation and chronic injury or disease
Don’t just treat the parasites
Consider spread between wild and domestic animals
Challenges of treatment (duration, FPA, administration, license)