Parasitic Diseases 4-H Veterinary Science Extension Veterinary Medicine Texas AgriLife Extension Service College of Veterinary Medicine and Biomedical Sciences Texas A&M System http://aevm.tamu.edu
Dec 22, 2015
Parasitic Diseases
4-H Veterinary ScienceExtension Veterinary Medicine
Texas AgriLife Extension ServiceCollege of Veterinary Medicine and Biomedical Sciences
Texas A&M Systemhttp://aevm.tamu.edu
Objectives
Describe diseases caused by arthropods Describe diseases caused by nematodes Describe diseases caused by tapeworms Describe diseases caused by flukes Describe diseases caused by protozoa
Overview
Remember Five infectious diseases
Bacterial Viral Fungal Parasitic Rickettsial
Infectious disease An illness due to a specific infectious agent or its
toxic products that arises through transmission of that agent or its products from an infected person, animal or reservoir to a susceptible host, either directly or indirectly
Parasite An organism that grows, feeds, and is sheltered
on or in a different organism while contributing nothing to the survival of its host
Types Arthropods Worms Protozoa
Arthropods Affect
Skin Digestive system
Examples Flies Ticks Fleas Lice Mites
Worms Affect
Skin Digestive system Circulatory system
Types Nematodes Tapeworms Flukes
Protozoa Single-celled organisms Affects
Digestive system Reproductive system
Types Amoebas Ciliates
Infestation To inhabit or overrun in numbers or quantities
large enough to be harmful, threatening, or obnoxious
Infection Invasion by and multiplication of pathogenic
microorganisms in a bodily part or tissue, which may produce subsequent tissue injury and progress to overt disease through a variety of cellular or toxic mechanisms
Parasites may be vectors Mechanical
Carries the pathogen, but the pathogen is not altered while on the vector
Example Arthropods Animals (wild or domestic) People
Biological An organism that is needed for the life cycle of a
pathogen Disease agent multiplies or develops within parasite Example
Arthropods
Skin
Arthropods Ectoparasites
External parasites Cause infestations Not worms, bacteria, viruses or fungi
Affect health Tissue damage Blood loss Annoyance Vectors
Flies Blood-suckers
Annoyance Anemia Disease transmission
Anaplasmosis Bluetongue Heartworms
Examples Horseflies Deerflies Stableflies Hornflies Mosquitoes Gnats
Non-blood suckers Annoyance Example
Houseflies
Housefly
Mosquito
Heartworms
Flies
Heelflies Larval stages
Cattle grubs Cause
Migratory damage Internal tissue Hide
Heelfly
Cattle grub
Development Process of a Heelfly
Ticks Two groups
Hard ticks Soft ticks
Adults are free-living
Hard ticks Feed for several days Vectors
Anaplasmosis Lyme disease
Soft Ticks Intermittent feeders Spinose ticks