Difference between revisions of "Parasites"

From Dog
Line 97: Line 97:
:::::''[[Giardia spp]]'', ''[[Cryptosporidium spp]]'', ''[[Isospora spp]]'', ''[[Acanthamoeba spp]]''
:::::''[[Giardia spp]]'', ''[[Cryptosporidium spp]]'', ''[[Isospora spp]]'', ''[[Acanthamoeba spp]]''
:::::''[[Toxoplasma|Toxoplasma gondii]]'', ''[[Hammondia hammondi]]'', ''[[Sarcocystis spp]]'', ''[[Neospora spp]]''
:::::''[[Toxoplasma|Toxoplasma gondii]]'', ''[[Hammondia hammondi]]'', ''[[Sarcocystis spp]]'', ''[[Neospora spp]]''
:::::''[[Balantidium coli]]'', ''[[Tritrichomonas spp]]''   
:::::''[[Balantidium coli]]'', ''[[Pentatrichomonas spp|Pentatrichomonas hominis]]'', ''[[Tritrichomonas spp]]''   
:::::''[[Strongyloides spp]]'', ''[[Alaria marcianae]]'', ''[[Ancylostoma spp|Ancylostoma braziliense]]'', ''[[Toxocara spp|Toxocara canis]]''
:::::''[[Strongyloides spp]]'', ''[[Alaria marcianae]]'', ''[[Ancylostoma spp|Ancylostoma braziliense]]'', ''[[Toxocara spp|Toxocara canis]]''

Revision as of 04:49, 24 October 2012

Adult hirudinid leech removed from the nasal cavity of a dog
The common flea tapeworm of cats, Dipylidium caninum
Trichuris spp - adult whipworms
Post-mortem specimen from a dog which died suddenly from D. immitis infection
Ctenocephalides canis - the dog flea
Adult Heterodoxus spiniger - dog biting louse
Egg of Toxocara canis under light microscopy, showing the characteristic pitted-edge surface[1]
Giardia spp parasite, a common cause of diarrhoea in cats

The term parasitism may be defined as a two-species association in which one species, the parasite, lives on or in a second species, the host, for a significant period of its life and obtains nourishment from it. This is a commonly accepted working definition of parasitism and using it we can emphasize several important features of the host-parasite relationship. Parasitism always involves two species, the parasite and the host. Many of these parasitic associations produce pathological changes in hosts that may result in disease. Successful treatment and control of parasitic diseases requires not only comprehensive information about the parasite itself but also a good understanding of the nature of parasites' interactions with their hosts. The parasite is always the beneficiary and the host is always the provider in any host-parasite relationship[2].

This definition of parasitism is a general one but it tells us nothing about parasites themselves. It does not address which particular infectious organisms of domestic animals we might include in the realm of parasitology. The protozoa, arthropods and helminths are traditionally defined as parasites. However, there are members of the scientific community who designate all infectious agents of animals as parasites including viruses, protozoa, bacteria and fungi as well as the arthropods, helminths and protozoa. Within this broad definition, parasites are further divided into microparasites and macroparasites.

Various nematodes transmits nematophagous fungal symbionts, Pochonia chlamydosporia[3] and Paecilomyces lilacinus[4] and control of these fungi affects survival and reproductive performance of the nematode[5].

Similarly, the hematophagous nematode Dirofilaria immitis transmits the endosymbiont alphaproteobacteria Wolbachia spp, which affects both its survival, growth and reporuction, and their importance cannot be overemphasized.

In low socioeconomic regions of the world, co-infections with ecto-, endo- and hemo-parasites is extremely common[6].

The following subsections summarize the common endo- and ectoparasites of dogs:


Cuterebra emasculator, Cochliomyia spp, Phortica variegata, Hippobosca longipennis
Ctenocephalides spp, Echidnophaga gallinacea, Pulex irritans
Ixodes holocyclus, Rhipicephalus sanguineus
Demodex spp, Notoedres spp, Eutrombicula alfreddugesi, Neotrombicula autumnalis
Otodectes spp, Cheyletiella spp, Straelensia cynotis
Sarcoptes spp
Heterodoxus spiniger, Trichodectes canis
Onchocerca lupi, Dirofilaria repens, Dracunculus insignis, Dipetalonema reconditum, Cercopithifilaria spp, Acanthocheilonema spp, Microfilaria auquieri, Crenosoma vulpis


Thelazia spp
Toxoplasma spp, Cuterebra spp, Toxocara canis, Trypanosoma cruzi


Linguatula serrata
  • Leech
Myxobdella annandalei


Dirofilaria immitis, Brugia malayi, Acanthocheilonema spp, Dipetalonema repens, Microfilaria auquieri
Babesia spp, Leishmania spp, Trypanosoma spp, Hepatozoon spp
Anaplasma spp, Bartonella spp, Rickettsia spp, Ehrlichia spp, Mycoplasma spp


Toxocara cati, Dirofilaria immitis
Toxoplasma spp
Cuterebra emasculator


Dirofilaria spp, Strongyloides spp, Filaroides osleri, Angiostrongylus vasorum, Eucoleus aerophilus, Crenosoma vulpis
Aelurostrongylus abstrusus, Paragonimus spp


Dirofilaria immitis, Angiostrongylus vasorum, Crenosoma vulpis


Parametorchis complexus, Clonorchis sinensis, Opisthorchis spp, Metagonimus yokogawai

Reproductive tract

Brucella canis


Dioctophyme renale


Dipetalonema reconditum, Cuterebra spp
Dirofilaria immitis
Parametorchis complexus
Trichinella spiralis
Hepatozoon spp, Neospora spp, Cytauxzoon felis


Tetratrichomonas felistomae
Linguatula serrata


Ollulanus tricuspis, Physaloptera spp, Aonchotheca putorii, Spirocerca lupi

Small intestine

Giardia spp, Cryptosporidium spp, Isospora spp, Acanthamoeba spp
Toxoplasma gondii, Hammondia hammondi, Sarcocystis spp, Neospora spp
Balantidium coli, Pentatrichomonas hominis, Tritrichomonas spp
Strongyloides spp, Alaria marcianae, Ancylostoma braziliense, Toxocara canis
Uncinaria stenocephala, Diphylobothrium latum, Echinococcus multilocularis
Hammondia hammondi, Mesocestoides spp, Toxascaris leonina
Toxocara cati,
Heterobilharzia americana, Alaria spp, Nanophyetus salmincola, Metagonimus yokogawai, Haplorchis spp, Stellantchasmus spp
Stictodora spp, Centrocestus spp, Cryptocotyle lingua, Apophallus donicum, Acanthotrema felis
Mesocestoides lineatus, Taenia hydatigena, Dipylidium caninum
Spirometra mansonoides, Diphyllobothrium latum, Echinococcus multilocularis, Spirometra mansonoides

Large intestine

Balantidium coli, Blastocystis spp
Strongyloides spp, Trichuris vulpis


  1. Buckelew
  2. University of Pennsylvania
  3. Araujo JM et al' (2012) Survival of Pochonia chlamydosporia in the gastrointestinal tract of experimentally treated dogs. Res Vet Sci 93(2):803-806
  4. Carvalho RO et al (2010) Ovicidal activity of Pochonia chlamydosporia and Paecilomyces lilacinus on Toxocara canis eggs. Vet Parasitol 169(1-2):123-127
  5. Frassy LN et al (2010) Destruction of Toxocara canis eggs by the nematophagous fungus Pochonia chlamydosporia. Rev Soc Bras Med Trop 43(1):102-104
  6. Bwalya EC et al (2011) Prevalence of canine gastrointestinal helminths in urban Lusaka and rural Katete Districts of Zambia. Prev Vet Med 100(3-4):252-255