Endoparasites

Endoparasites

1. Trematrodes a.ka Flukes

   • Monogenea= direct lifecycle
   • Digenea=intermediate host needed
   • Not Common in dogs/cats in U.K. Liver fluke in rabbits

2. Nematodes (Roundworm)

   • Toxocara canis ZOONOTIC
     • Ocular larval migrans
       • Visceral Larvae migrans= ASYMPTOMATIC, humans ingest egg/larvae. Severe when clinical signs appear
     • Puppies affected worst= pot-belly, reduced intestinal motility, failure to thrive, respiratory distress
     • Eggs can survive year in soil
   • Toxocara cati- most common cat worm
     • Pneumonia in kittens in heavy larval migrations, possibly less zoonotic
   • Anclyostoma caninum (HOOKWORM)
     • Feed off of blood in Small Intestine
     • Bloody D+, anaemia, death
     • Imported puppies, ZOONOTIC SKIN PENETRATION
   • Trichuris Vulpis (WHIPWORM)
     • Low level infestation well tolerated. HEAVY INFECTION=Bloody D+ & acute illness
     • Eggs survive 2yrs in kennels
   • Strongyles (horses/donkeys)
     • Trichonemes, cyathostomes, small strongyles
     • Caecum/colon migrate into mucosa causing inflammation.
     • Anaemia, D+, un-thriftiness
     • Faecal egg count every 6-8 weeks. Faecal larvae appear red.
   • Anglostrongylus (LUNG WORM)
     • Left ventricle & pulmonary artery
     • ASYMPTOMATIC
       • Couch, coagulopathy, anaemia, sudden death?
       • Diagnosed by whole worms at PM, faecal sample for larvae, Bronchial Alveolar Lavage examination for larvae, ELISA test
     • Milbemax, Advocate, Panacur
   • Dirofilaria Immitas (HEART WORM)
     • Right side of heart
     • Pets travelling to U.K
     • Mosquitos intermediate host=transmits infectious larval stages. ZOONOTIC
     • Chronic right sided heart failure, endocarditis, pulmonary embolism caused by dying worms, most dogs effected are over 2 yrs old
     • Stabilise cardiovascular system before anthelmintics. CAREFUL Monitoring

3. Cestodes (TAPEWORM) Tape like body, no alimentary tract, each segment 2 pairs male & female genitalia

   • Rarely cause harm in adult animals but humans at risk of cysts
   • Drontal, Droncit, Milbemac, Profender
   • Taenia spp: larvae need intermediate host, definitive host for adults (HUMANS)
     • T.solium (Pork TW), T.saginata (Beef TW), Intermediate host for T.Multiceps. Cysts in meat transmit
   • Dipylidium Caninum
     • Fleas & lice intermediate host. Dog & human definitive host
       • Flea control!
       • Echinococcus, E. granulosus, E. multilocularis (not endemic in U.K)
         • PETS travel scheme
     • Larval stages in man=death?
   • Transmission via segments survive 2 years in ground, ingested by intermediate host, 12 months for cysts to develop, carnivore eats, adult worms rarely show clinicalsigns
     • Diagnosis through hyatid cysts. Difficult in dogs as segments small & Intermittent, coproantigenic ELISA test

4. Protozoa (unicellular eukarote (symbitic/commensal)

   • Leishmania (ZOONOTIC) Sandfly intermediate host. activates macrophages surrounded by lymphocytes.
     • Cutaneous form: shallow ulcers of lip/eyelid)
     • Visceral Form: loss of hair,anaemia, lymphadenophathy, pyrexia
     • arely treat/ humans at risk. Insecticides prevewnt, collar? dogs secreate in blood.
   • Tririchomonas (cars/kittens)
     • Profuse, watery D+
     • ALMOST IMPOSSIBLE TREAT, self cure at pubierty
       • 3-4months D+ in house?
       • Metronidazole?
   • Giardia
     • ZOONOTIC: infected water sources >wild mammals
     • Watery D+, V+, GI signs
     • Pooled faecal sample, immunodetection kit
     • Vaccine in U.S, fenbedazole/metronidazole in U.K.
   • Coccidia causes changes in intestinal mucosa, severity dependent on parasite density
     • Cell rupture, V+, D+ due to flattened villi resulting in poor absorption, D+ and weightloss
       • Eimeria affects poultry, cattle, sheep, goats, pigs, horse, rabbiits-epithelial cells of intestine, kidney, liver in other species
       • Isopora: pigs ,dog, cat, man
       • Cryptosporidium affects most domestics & man
         • Watery D+, depression in puppies & kittens, NO TREATMENT, diagnose through acid-fast red stain
   • Toxoplasmosis (ZOONOTIC), all felids, man and some birds intermediate host.
     • Pathology only in intestinal stages (lives in intestinal wall), congenital defects seen in pregnancy if infection for first time, heavy infection in cardiac, brain, lungs & liver
     • Pregnant women at risk of miscarriage/ hydrocephalus in unborn baby.
     • HYGIENE!
     • Clinical signs not seen in adults, kittens may be ataxic
   • Neospora: Puppies worst affected
     • Similar to toxoplasmosis-ascending paralysis & death. Transmitted through cattle tissue containing cysts, causes limb deformities in calves.
   • Encephalitozoan cuniculi, spores transmitted in urine, mainly affects rabbits (52%)
     • Neurological, ocular, renal disease. ZOONOTIC
       • Panacur & hutch hygiene

5. Anthelmintic resistance becoming increasing concern. 3 licensed categories: benzimidazoles, nicotinic agonists, macrocytic lactones ( tolerance vs resistance)

6. Hydrobiosis is arrested larval development, larvae stays in faeces/ pause development.

7. Prepatent Period (PPE), Parasitic Gastroenteritis (PGE)