the orderly classification of organisms into appropriate categories
the genus & species name of an organism, the genus name is capitalized, however the species name is not, both genus and species name is italicized or underlined
organisms that live on or within an animal, feeding on the animal's tissue or body fluids or competing directly for the animal's food
parasites that live on an animal; ectoparasite; external parasites infest their host
parasites that live within an animal; endoparasite; internal parasites infect their host
the animal harboring the parasite; the animal in which or on which the parasite lives
host that harbors the adult or sexually mature stages of the parasite; the animal infected or infested by the adult stage of the parasite; primary host; final host
host that harbors the larval or sexually immature stages of the parasite; parasites can have more than one intermediate host; secondary host
host that carries the parasite to another host, but the parasite does not undergo any development in this host (the parasite remains arrested, encysted, or in suspended animation); transport host
host that can be infected by a parasite, but no development of the parasite occurs in this host; a dead-end host cannot transmit the parasite to another host
the development of a parasite through its various stages, including how the parasite develops and how it reproduces
direct life cycle
a parasitic life cycle that requires no intermediate host for completion
indirect life cycle
a parasitic life cycle that requires one or more intermediate host(s) for completion
the life cycle stage of a parasite in which the parasite is sexually immature
the period of time between the entry of infective parasites into the host's body and the time at which they can be demonstrated in the host's blood, urine, or feces; the time from the point of infection by a nematode until a specific diagnostic stage can be recovered
an arthropod (insect) that transmits or carries the causative organisms of disease; an intermediate host that transfers a pathogen or a parasite to another organism
the pathologic mechanisms that occur in the development of disease; how the parasites inflict harm upon the host
periparturient rise (PPR)
an increase in egg production by the parasite at or near the time of parturition by the host
hypobiosis (arrested larval development)
the temporary cessation in the development of a parasite; encysted; in suspended animation
a dewormer; a chemical compounds developed to kill roundworms, tapeworms, flukes, and thorny-headed worms
submandibular edema; a gravity-dependent accumulation of fluid in the intermandibular space due to low blood protein from anemia or a disturbance in digestion; hypoproteinemia results in bottle jaw
the process of deworming at an early age and continuing to deworm at strategic intervals before environmental contamination has occurred; minimizes the number of parasitic eggs & larvae in the environment to a "safe" level that is not harmful to grazing hosts
Companion Animal Parasite Council; creates guidelines for optimal control of internal and external parasites
covers the exterior body surface of the nematode and extends into all body openings
buccal capsule (cavity)
large opening that connects to the mouth of a nematode; connects the mouth to the esophagus
part of the digestive tract in a nematode that follows the buccal cavity
male nematode intromittent organs ("penis") associated with the copulatory bursa
the posterior lateral expansion on the male nematode that serves to hold onto or to grasp the female nematode during the mating process
How many molts do nematode larvae normally undergo in a complete parasitic life cycle?
4 molts (L1-L2, L2-L3, L3-L4, L4-L5)
Which larval stage is usually the infective stage?
L3 or the third stage larvae
What is the ideal environmental temperature range for the hatching of most nematode eggs?
What is the ideal environmental humidity range for the hatching of most nematode eggs?
Which trichostrongyles inhabit the abomasum of domestic ruminants?
HOT worms: Haemonchus spp., Ostertagia spp., Trichostrongylus spp.
What is the life cycle of the "HOT" worms?
Life cycle is direct. Prepatent period is 3 weeks. L-3 is the infective larval stage. L-1 and L-2 are free living organisms found in the soil, the host ingests the infective L-3 while grazing starting the infection, adults of all 3 worms live on the surface of the abomasal mucosa in ruminants
What is the prepatent peroid for the "HOT" worms?
approximately 3 weeks
What is meant by the term "safe pasture"?
Describe 3 methods for the control of trichostrongyles as discussed in lecture.
pasture rotation, dose & move, strategic deworming
Describe the etiology in a calf with ostertagiasis.
Describe the pathogenesis in a calf with ostertagiasis.
the Ostertagia spp. larvae develop in the glands of the abomasum that secrete hydrochloric acid & as the larvae grow, they destroy the gastric gland & cause gastritis, & they form nodules on the abomasal mucosa, when enough gastric glands are affected the abomasal pH rises & leads to the inability to properly digest food, causing weight loss
Describe the clinical signs in a calf with ostertagiasis.
watery diarrhea, anorexia, weight loss, bottle jaw, failure to gain weight
Describe the necropsy findings in a calf with ostertagiasis.
Low weight, high abomasal pH, hypoproteinemia, bottle jaw, Ostertagia spp. found in the glands of the abomasum, gastric glands are destroyed, gastritis
Describe the etiology of haemonchosis.
Describe the pathogenesis of haemonchosis.
blood loss leading to anemia
Describe the clinical signs of haemonchosis.
anemia, bottle jaw, weakness, weight loss, black tarry feces
Which hosts can Trichostrongylus parasitize?
ruminants (abomasum), horses (stomach), pigs (stomach), rabbits (stomach/ small intestines), & fowl (small/ large intestines)
Describe the pathogenesis of Trichostrongylus.
What is the common name of Cooperia spp?
Cooper's worm or cattle bankrupt worm
What is the host of Cooperia spp?
What is the site of Cooperia spp?
What is the pathogenesis of Cooperia spp?
blood sucking; enteritis
Name the slender, small, reddish worm found in the stomach of pigs.
What other trichostrongylid can inhabit the stomach of pigs?
Which genera of trichostrongylids produces an egg that is football-shaped and twice the size of the typical trichostrongyle egg?
What is the scientific name of the trichostrongyle that may rarely inhabit the stomach of cats (and pigs)?
What is the common name of the trichostrongyle that may rarely inhabit the stomach of cats (and pigs)?
cat stomach worm
Describe the life cycle of Dictyocaulus spp.
Life cycle is direct. Prepatent period is about 4 weeks. L-3 is the infective larval stage. Larvae are passed in feces where the grow & molt L1 to L3; L3 larvae are ingested; larvae migrate into lymph vessels & follow lymph vessels to heart where they grow & molt; the blood & larvae flow into the lungs where the adults live; eggs are coughed up and swallowed; eggs hatch into larvae in intestines & larvae are passed in feces
Describe the control of Dictyocaulus spp.
Control in cattle should be focused on pasture rotation, preventing the land from being overgrazed & keeping herds away from low land in rainy seasons.
Which diagnostic technique is useful for demonstrating Dictyocaulus larvae?
common name of Ostertagia spp.
brown stomach worm
host of Ostertagia spp.
site of Ostertagia spp.
common name of Haemonchus spp.
barber pole worm
host of Haemonchus spp.
site of Haemonchus spp.
common name of Trichostrongylus spp.
host of Trichostrongylus spp.
ruminants, horses, pigs, rabbits, fowl
site of Trichostrongylus spp.
ruminants - abomasum, horses and pigs - stomach, rabbits - stomach/ small intestines, fowl - small/ large intestines
common name of Cooperia spp.
Cooper's worm or cattle bankrupt worm
host of Cooperia spp.
site of Cooperia spp.
common name of Hyostrongylus rubidus
red stomach worm
host of Hyostrongylus rubidus
site of Hyostrongylus rubidus
common name of Nematodirus spp.
thread-necked intestinal worm or thin-necked intestinal worm
host of Nematodirus spp.
site of Nematodirus spp.
common name of Ollulanus tricuspis
cat stomach worm
common name of Dictyocaulus spp.
host of Dictocaulus spp.
ruminants, horses, & donkeys
site of Dictocaulus spp.
trachea & bronchi
Describe the procedure for performing the Baermann technique.
Spread a piece of cheesecloth or gauze square on the support screen in the Baermann apparatus, place 5-15g of fecal/ tissue/ soil in the cheesecloth, folding excess over the top of the sample. Be sure that the sample is covered by warm water. Allow to sit overnight. Hold a microscope slide under the cut off point & examine a large drop microscopically.
Describe the purpose for performing the Baermann technique.
This method takes advantage of the fact that warm water stimulates nematode larvae in a sample to move about. Once the larvae move out of the sample, they relax in the warm water and sink to the bottom of the container.