1. skin penetration-infective stage 2. oral infection- prepatent period 14 days 3. transmammary- A. caninum only to date 4. intrauterine- A. caninum only to date 5. mammalian intermediate host
What is the lifecycle of the hookworm?
eggs are passed in feces--L1Matures with warmth--L2--L3 (infective stage)--L3 is swallowed or penetrates skin--L3 migrates through body tissues to lungs--larva is coughed up--larva is swallowed by host--larva matures to adult stage and attaches to intestine adults opens a capillary bed--male and female mate and produce eggs-- eggs are passed in feces
What does ancylostomiasis inhabit?
small intestins only-causing dark tarry feces
What are some clinical signs of ancylostomiasis?
1. far more devastating in puppy 2. dark tarry stool diarrhea 3. pale mucus membranes with anemia 4. microcytic/hypochromic 5. playing today, motionless tomorrow, dead 3rd day. 6. adults NOT seen in feces too small, only eggs
_ is known as a blood sucker, it feeds on the mucosa of the small intestines (glucose) resulting in bleeding of the mucosal lining. NOT a blood sucker
Life cycle of Ancylostoma caninum
Dog consumes the 3rd stage larvae or the 3rd stage larvae penetrates the skin of animal--larvae mature in the sm. intestines and feed--mature worms copulate and start to produce egg--two weeks after consumption of 3rd stage--four weeks after skin penetration of 3rd stage-- eggs are passed in feces and hatch in 2-8days
Once the 3rd stage larvae of Ancylostoma caninum is consumed and passes to the sm. intestines, one of two avenues may be taken:
1. larvae may mature to adult 2. larvae may penetrate the intestine wall and migrate through the tissues and encyst within the skeletal muscles or gut wall becoming dormant
The dormant larvae of Ancylostoma may becoming activated by what?
Hormones of pregnancy or other stimuli where they can migrate to the small intestine or go to infest fetuses inutero
__ and __ can both penetrate the skin resulting in cutaneous larval migrans
ancylostoma caninum and ancylostoma brazilliense
What is the diagnosis of hooks?
eggs in the feces as larvae are hard to see
What is the prepatent period for hooks?
milbemycin oxime & lufenuron
What are some ways of controling of hooks?
1. feces removal 2. sould can be periodically treated with salt 160g/liter boiling water 3. concret runs cleaned well 4. female should be de-wormed prior to breeding
1. Adult in intestines 2. eggs in feces on ground 3. feces contain L2 (infective stage) larva hatch in duodenum 4. larva migrate through various tissues 5. larvae migrate through the lungs and coughed up and swallowed
As will all parasites, the females are usually larger in size, as with ascarids where the male is __cm and the female is __ cm
male- 7-9cm female 10-17cm
How can Ascarids be transmitted?
comsumption of eggs, second stage larvae consumption, transplacentally, transmammary, and predation of paratenic host
from ___ (place and date)-- the risk of direct transmission to Toxocara canis to man through contact only with dogs has now been confirmed by a scientific study.
Monheim, May 5, 2003
Does Ascarid eggs have to incubate in the soil?
until now it was assumed the edd and 1st stage larve must spend 2-7 weeks in soil to develop. So the answer is NO
1. Dog consumes second stage larva 2. Larva penetrates the stomach and enters the hepatic portal circulation (Inside liver) 3. Larva migrates through the liver parenchyma(tissue of organ) 4. Larva enters the posterior vena cava and goes to lungs(through the heart, rt. atrium, rt. ventricle, pulm artery) 5. larva migrates up trachea to the pharynx where they are swallowed 6. following a molt in the stomach to stage 3, the parasite goes to the sm intestines to molt TWICE
__ what are white areas in the liver called? This is caused by the trachmigration route killing the liver cells
__ is the largest ascarid in dogs living in the small intestines and are long white and often straight in contrast to the worms of Physaloptera rara which lives in the stomach and is continuous C shaped through out its life
What is the prepatent period for ascarids?
21 days- 3 weeks
What is the life cycle for Ascarids?
1. Dog or cat ingest the eggs, 2nd stage or paratenic 2. Egg will hatch in stomach and molt to 2nd stage 3. 2nd stage larvae invade the bowel, move to the liver and go to lungs via vena cava 4. Larvae enter alveoli, coughed up into trachea & mouth, are awallowed and mature in the sm intestine 5. When female is pregnant (hormones), larvae are activated to migrate to placenta and into lungs of pups or mammary glands where they are shed in milk.
Larvae of both Ascarids and Ancylostoma that do not follow the normal routes of migration and as a result they encyst in the muscles in a __ state
__ is a term for a state of arrested development.
There are really three forms of both the ascarid and ancylostoma in animals body, not in the egg form. what are they?
1. adult- in intestines mostly 2. visceral migrating larvae 3. the encysted larval form
What are some signs of ascarid infections in prenatal infected pups?
a. abdominal cramps b. intersussusception with constipation(difficult)/obstipation(blockage)/dischezia(painful evacuation)
What are some signs of ascarid infections in adults infected?
a. gastrointestinal upset (diarrhea and vomiting) b. respiratory disorders due to tracheal migration(coughing) c. "pot belled" appearance and emaciation d. dull hair coat
What is in "Happy Jack"
piperazine, kills all round
When foreign larvae enter the __ host strange migratory routes are assumed by the larvae.
__ seen in Toxocara canis and Toxocara cati (this implies migration in the liver primarily)
If visceral lraval migrans is ocular it is called__
Ocular Larva Migrans (OLM)
__ million people in the US have been infected with the larvae of T. canis and T. cati
__ children alone are affected annually by ascarids, with __ severe ocular larva migrans resulting in blindness
10 thousand children and 750-blindness
__ % of welfare children in Mississippi were positive for ascarids due to oral ingestion (report by State Health Office)
__ cause in humans by Ancylostoma brazilienses and A. caninum but most authorities and text will list only A. brazilienses causing cutaneous larval migrans in zoonotic cases
Cutaneous Larval Migrans
What is the nickname for Cutaneous Larval Migrans?
What are some similarities between Toxocara mystax(T.cati) and Toxocara canis?
1. Toxocara mystax is the common ascarid to cats like T.canis is to the dog 2. Transtracheal migration is exactly the same as in T. canis 3. Although not written, it is belived that larval leak does occur with cats and T. cati
What are some differences between Toxocara mystax (T. cati) and Toxocara canis?
1. Transplacental route of infection does not occur with T. cati. Transmammary is the route in cats.
__ does occurs in both the dog and cat. And does NO visceral migration.
__ follows a mucosal migration with the 2nd and 3rd molts occuring in the mucosa wall and the 4th stage entering the lumen of the gut to mature.
What is the prepatent period of Toxascaris leonina?
What are the 2 ways that Toxascaris leonina is transmissed?
1. ingestion of the eggs(or larva too) -- most common method 2. Ingestion of the paratenic host
What are some signs of Toxascaris leonina?
minimal due to the lack of pathogenicity with no transplacental and no transmammary transmission; therefore the animal is not effected until near adulthood
What is the life cycle of Toxascaris leonina?
ingestion of eggs- hatch- molts- and mature to adult all within the intestinal tract
Raccoons typically defecate in the same spot over and over again, what is the place called?
__ has been responsible for severe neurologic disease and the death of several childern in the United States
What are 3 floation solutions used?
1. Sodium nitrate 2. Zinc sulfate 3. Sheather's
What is the 3rd most common Nematode?
What are the common whipworms?
1. Trichuris vulpis- dog 2. Trichurs campanula- cat 3. trichurs serrate- cat 4. Trichuris trichura- man, pig and monkey
unlike ascarids and ancylostoma that inhabit the small intestins, __ inhabit the cecum where they firmly attach to the anterior end and embed in the mucosa.
__ are the most common pathological worms encountered in veterinary medicine and human medicine.
Almost all puppies born in the US are infected with Toxocara canis and high percentage with Ancylostoma caninum; these puppies can begin to shed eggs as young as __
2 to 3 weeks of age
Hookworms are a well-known cause of cutaneous larva migrans (CLM) and recently, A. caninum has been recognized to be a cause of __
chronic enterocolitis (Humans only)
Several patients with __ were found to be infected with a single A. caninum adult, and serologic testing indicates that infection with this organism may be very common.
Nematodes have arelatively large body cavity (__) containing fluid under a pressure.
The basic excretory system of nematodes consists of paired __ with a common midventral excretory pore and ducts that run nearly the full lenght of the body.
Male nematodes caudal engs are often equipped qith a cuticular expansion called a ___
What are the stages of development of nematodes?
1 cell, morula, vermiform embryo,
What is the difference between vermiform embryo and 1st stage larvae?
The former contains only one cell clusters as organs, whereas the latter displays clearly recognizable organs( esophagus, intestine, excretory organs)
What are the 7 test that tell us what parasite we are dealing with? (in order from best to worst)