Introduction

• Parasitology


  The study of parasites
• Parasites

  Organisms (bacteria, viruses, protozoa, helminths, arthropods) plants or animals, which live within some other organisms for their survival
• Hosts


  Plants or animals or other organisms where the parasites depend for their existence
• No host


  No parasite
• No parasite


  No host
• Parasitologist


  A quaint person who seeks truth in strange places; a person who sits on one stool, staring at one another
• Three Divisions of Veterinary Parasitology

  • Vet. Entomology
  • Vet Protozoology
  • Vet Helminthology
• Vet. Entomology

  • Deals on the different species of arthropods, are devoted to ticks, mites, insects and their dispersion, role as vectors of disease, and their control
• Vet Protozoology

  • Deals with directly transmitted and vector-borne infections and their control, vector -> mosquitoes -> transmit protozoans
• Vet Helminthology

  • Deals on the study of worms, concerns the life cycles, pathogenesis, clinical signs, epidemiology and chemotherapy and the integrated control of the nematodes, trematodes and cestodes
• Ringworm is not included in Veterinary Parasitology because it is caused by Fungi
• Not all flukes are flat
• Important Personalities in Parasitology

  • Francisco Redi – Father of Parasitology
  • Anthony Van Leewenhook
  • Muller
  • Peacock
  • Dubini
  • Gros
  • Abielgard
  • Kucjenmeister
  • Rudolphi
  • Malstem
  • Theobald Smith and Kibuorne
  • Leukart
  • Elnikov
  • David Bruce
  • Manson
  • Smith and Kilbourne
  • Ross and Grassi
  • Dr. Liberio Gomez
  • Dr. Candida Africa (MD)
  • Dr. Marcos Tubangui (DVM)
• Homogenetic association

  Those between individuals of the same genotype
• Heterogenetic association


  Those between individuals of different genotype
• Symbiosis

  Literally means 'living together', a relationship wherein both partners benefit
• Phoresis


  Exist when two symbionts are merely 'traveling together', there is no physiological or biochemical dependence on the part of either participant
• Mutualism


  Describes a relation in which both partners benefit from the association
• Commensalism

  One partner benefits from the association, but the host is neither helped nor harmed
• Facultative commensalism

  The commensal may not be required to participate in an association to survive
• Obligate commensalism


  They are not found except on other organisms, especially crustaceans
• Epidemiology


  Division of science concerned with defining and explaining the interrelationship of the host, agent, and environment in causing disease
• Zoonoses

  Transmission of the disease between man and animals
• Vector

  An arthropod or other invertebrate which transmits the parasite from one vertebrate host to another
• Infection

  Parasitism by an internal parasite
• Infestation

  Parasitism by an external parasite
• Life cycle


  The development of a parasite through its various stages
• Quantitative host range or qualitative host spectrum


  The amount of parasitism in the various hosts
• Parasite impasse


  A condition in which the parasites survive in the host without multiplication
• Ecology

  The study of the relationship between organisms and their environment
• Organ specificity

  Associated with host specificity is the organ where the parasites are present
• Reservoir host


  Any animal that harbors an infection that can be transmitted to humans, even if the animal is a normal host of the parasite
• Types of Larva

  • Oligopod larva
  • Apodous larva
  • Polypod larva
• Types of Pupa

  • Coarctate pupa
  • Obtect pupa
• Obligate parasites


  They can not complete their life cycle without spending at least part of the time in a parasitic relationship, have free living stages outside any host, including some period of time in the external environment within a protective eggshell or cyst
• Facultative parasites


  Are not normally parasitic but can become so when they are accidentally eaten or enter a wound or other body orifice
• Optional occasional parasites

  Those that briefly visit their host to obtain nourishment but not dependent upon them for either nourishment or shelter
• Obligate occasional parasites


  Those that do not permanently live upon their host but are dependent upon them for nourishment and to some extent for shelter
• Transitory parasites


  Are limited to definitive stage or stages in their life cycle, during which time, parasitism is obligate or continuous
• Permanent parasite


  Those that extend from the time of hatching of the eggs to the time the eggs are produced by the adult