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WorksheetsNematoda
Total questions: 133
Worksheet time: 1hrs 7mins
Genus Strongyloides (order Rhabditida) contain parasites that locate in the small intestine of a wide range of hosts and have parasitic and free-living stages in their lifecycle. In the environment larvae of Strongyloides can develop through a homogonic (L1-L2-L3) or a heterogonic (L1-L2-L3- L4-adults). What are the most important factors that might influence the development of larvae of Strongyloides spp. (homogonic vs heterogonic lifecycle)?
The host immunity and environmental factors (temperature, humidity etc)
The host immunity and the age of the female parasites
The age of the female parasites and environmental factors (temperature, humidity etc
The number of the males in the host and environmental factors (temperature, humidity etc)
The host immunity and number of the males in the host
Genus Strongyloides (order Rhabditida) contain parasites that have only females as the parasitic stage and can infect the host in many ways. How do the hosts become infected with Strongyloides spp.?
With larvae from environment and larvae via placenta and milk
With embrionated eggs from environment, larvae via placenta and autoinfection
With larvae from environment, larvae from milk and by autoinfection
With embrionated eggs and larvae from environment and by autoinfection
Order Strongylida (Class Nematoda) contains some of the most important roundworms that infect animals and humans. Parasites from order Strongylida are characterized by the following morphological features
Males have a bursa at the posterior end and the eggs are thick shelled, in a one cell stage
Males have a bursa at the posterior end and the eggs are thin shelled, in a morula stage
Males have a coiled posterior end and the eggs are thin shelled, in a morula stage
Males have a blunt posterior end and the eggs are thin shelled, in a morula stage
Males have a blunt posterior end and the eggs are thick shelled, in a one cell stage
In the environment eggs of parasites from order Strongylida (class Nematoda) will develop through many stages to reach the infective stage (L3). The speed of development and survival of the larvae on the pastures are important factors in the epidemiology of the disease caused by this parasites. The most important factors that determine the speed of development and survival of the larvae of Strongylida parasites on pasture are
Moisture and temperature
Moisture and the presence of organic matter
Temperature and the presence of organic matter
Moisture and the host immune response of the host
Temperature and the host immune response
Larvae of many species from superfamily Trichostrongyloidea may undergo a period of arrested/inhibited development (hypobiosis) in the third or early fourth stages of development. What are the most important factors that might induce larvae of species from this superfamily to enter hypobiosis in the host?
Sex of the host and environmental factors
Age of the host and the host immune response
Environmental factors and the host immune response
Sex of the host and the host immune response;
Breed of the host and environmental factors
The phenomenon of hypbiosis (arrested or inhibition of development) is an important part of the biology of worms from superfamily Trichostrongyloidea. Hypobiotic larvae of species from superfamily Trichostrongyloidea may resume development and turn into adult parasites when
The environmental conditions are favourable for development of their offspring and/or in ewes during parturition and lactation
The environmental conditions are favourable for development of their offspring and/or in ewes during the breeding season
The adult population of parasites is removed by anthelminthic treatments and/or in males during the breeding season
The environmental conditions are favourable for development of their offspring and/or in males during the breeding season
The adult population of parasites is removed by anthelminthic treatments and/or the chemoresistance has developed
The number of eggs laid by female worms is an important factor in the epidemiology of parasitic diseases. One of most prolific parasite species from superfamily Trichostrongyloidea is
Haemonchus contortus
Trichostrongylus axei
Ostertagia ostertagi
Nematodirus battus
Cooperia curticei
Haemonchus contortus is the most important worm of sheep and goats grown in Queensland. Where does this worm locate in the body of the sheep and goats and what is it feeding on?
Locates in the abomasum and feeds on abomasal content
Locates in the abomasum and feeds on blood
Locates in the small intestine and feeds on intestinal conten
Locates in the small intestine and feeds on blood
Locates in the large intestine and feeds on blood
Superfamily Trichostrongyloidea comprises slender worms with a small mouth at the anterior end a bursa at the posterior end of the males. These parasites are very important for ruminant industry. From the following list select the sheep/goat worm that has a mouth provided with a tooth and feeds on blood
Haemonchus contortus
Cooperia curtice
Ostertagia ostertagi
Nematodirus battus
Trichostrongylus axei
Haemonchus contortus is an important parasite for sheep and goat industry in Australia. Considering the requirements of the larval stages of this parasite for development and survival in the environment in what areas outbreaks with this parasite are likely to be common in Australia?
Everywhere in Australia
Areas with cold and dry winters
Areas with warm and moist summers
Areas with cold and dry summers
Genus Haemonchus comprises worms that locate in the abomasum of the ruminants and feed on blood. The ruminants can become infected with Haemonchus spp by
Ingestion of third stage larvae with pasture and water
Ingestion of embrionated eggs with pasture or water
Ingestion of snails with pasture and water
Ingestion of onchospheres with pasture and water
Via milk
Order Strongylida contains important parasites for animal health that might pass through fours developmental stages in the environment: eggs, first stage larvae (L1), second stage larvae (L2) and third stage larvae (L3). From the list below select the Strongylida life stage that is likely to survive longest in the environment.
L3
L2
L1
Eggs in a morula stage
Embrionated eggs
Superfamily family Trichostrongyloidea (order Strongylida) comprises parasites that infect a wide range of hosts with most species locating in the gastrointestinal tract. In sheep and goats abomasal (trichostrongylid) worms up to 3 cm long and having a barber’s pole appearance are likely to be
Haemonchus spp
Trichostrongylus spp
Ostertagia spp
Cooperia curticei
Bunostomum trigonocephalum
Five thousand worms like those shown in Fig. 1 were found in the abomasum of a goat from a farm around Townsville that suddenly died showing severe anemia and weakness (Fig. 2). From the following list select the parasite that caused the death of the goat
Haemonchus contortus
Cooperia curticei
Trichostrongylus axei
Ostertagia ostertagi
Nematodirus battus
Five thousand worms like those shown in Fig. 1 from the previous slide were found in the abomasum of a goat from a farm around Townsville that suddenly died showing severe anemia and weakness (Fig. 2). From the following pictures select the eggs that are likely to be shed by goats infected with this parasite
Photo 1
Photo 3
Photo 2
Photo 4
Photo 5
Superfamily family Trichostrongyloidea (order Strongylida) comprises slender worms with a small mouth and a well developed bursa that commonly locate in the gastrointestinal tract. Species from the genus Nematodirus differ from most of the species from superfamily Trichostrongyloidea in that
Their eggs are bigger and the larval development takes place inside the eggs
Their eggs have an operculum and the larval development takes place inside the eggs
Their eggs are smaller and the larval development takes place inside the eggs
Their eggs are bigger and the larval development requires moisture and proper temperature
Their eggs are smaller and the larval development can be inhibited when the temperatures are low
Identify this parasite superfamily trichostongylodia
Haemonchus
Ostertagia
Toxacaris canis
Ancylatoma caninum
Morphological features of eggs are important criteria for identification of parasite species and confirmation of the diagnosis of parasitic diseases. Eggs like those shown in the attached photo were found in the faeces of a young sheep from Victoria (faecal floatation).Name the genus the eggs labeled ‘A’ belong to.
Nematodirus
Ostertagia
Haemonchus
Trichostrongylus
Cooperia
Ostertagia ostertagi is an important trichostrongylid worm (Class Nematoda, superfamily Trichstrongyloidea) of cattle from temperate areas. Type II Ostertagiosis is most likely caused by
Direct development of large numbers of adult Ostertagia ostertagi over a relatively short period of time
Synchronous maturation and emergence of large numbers of hypobiotic larvae of Ostertagia ostertagi from mucosa
Migration of the larvae of Ostertagia ostertagi through internal organs, especially liver, heart and lungs
Large numbers of female Ostertagia ostertagi that infected the host transcutaneously
Large numbers of female Ostertagia ostertagi that are feeding on blood
Nodules like those shown in the attached photo were found in the abomasum of a cow from Victoria. Select from the following list the parasite that is likely to have caused the nodules.
Ostertagia ostertagi
Nematodirus battus
Cooperia curticei
Trichostrongylus axei
Haemonchus contortus
Superfamily Trichostrongyloidea (order Strongylida) comprises parasites that infect a wide range of hosts with most species locating in the gastrointestinal tract. However, ruminants can be infected by whitish, filiform trichostrongylid nematodes that locate in the bronchi and trachea. From the following list select the genus the trichostrongylid worms that locate in the bronchi and trachea of ruminants belong to:
Ostertagia
Dictyocaulus
Nematodirus
4. Aelurostrongylus
Angiostrongylus
Identify this species superfamily trichostongylodia
Ostertagia
Haemonchus
Nematodirus
Ancylastoma caninum
Dictyocaulus filaria is a worm from superfamily Trichostrongyloidea that locates in the trachea and bronchi of sheep and goats. Small ruminants infected with this parasite will pass in their faeces
Thin shelled, embrionated eggs
Thin shelled, in a morula stage eggs
First stage larvae
Thick shelled, in a one cell stage eggs
Third stage larvae
Dictyocaulus filaria is a whitish trichostrongylid worm, up to 12 cm long, that locates in the bronchi and trachea of sheep and goats. The morphological features of the posterior end of the males from class Nematoda are important for identification of these worms. From the photos below select the posterior end that belongs to the male D. filaria
Photo 1
Photo 2
Photo 3
Photo 4
Photo 5
Pale nodules with a slightly depressed center in the abomasum of cattle are most likely caused by
Adults of Haemonchus contortus
Larvae of Ostertagia ostertagi
Adults of Dictyocaulus filaria
Larvae of Trichostrongylus axei
Larvae of Nematodirus battus
Larvae of many of the important trichostrongylid species may undergo a period of arrested/inhibited development (hypobiosis) in the third or early fourth larval stages. Select the parasite species that is well known for its propensity to arrest as early fourth stage larvae in the wall of the abomasum of cattle
Ostertagia ostertagi
Moniezia expansa
Haemonchus contortus
Trichostrongylus axei
Identify this parasite from the superfamily trichostongylodia
dictyocaulus filaria
Ostertagia
Haemonchus
Nematodirus
Genus Strongylus (superfamily Strongyloidea) contains parasites that are very common in horses that are using pastures. Adult worms of the species from genus Strongylus
Locate in the cranial mesenteric artery and feed on blood
Locate in the small intestine and feed on intestinal content
Locate in the large intestine and feed on blood
Locate in the small intestine and feed on blood
Locate in the abomasum and feed on blood
Strongylus vulgaris is an important nematode parasite of horses that in the adult stage locates in the large intestine and feeds on blood. Larvae of Strongylus vulgaris will migrate to and develop to the adult stage in
Cranial mesenteric artery
Liver
Lungs
Pancreas
Kidneys
Around 60 species of worms from class Nematoda locate in the large intestine of horses. Worms up to 2.5 cm long and with a big buccal capsule (as shown in the attached photo) found in the large intestine of an one year old horse belong to
Strongylus edentates
Strongylus vulgaris
Strongylus equinus
Chabertia ovina
Triodontophorus tenuicollis
Genus Strongylus contains important horse parasites that in the adult stage locate in the large intestine and feed on blood. Adults of Strongylus edentatus have at the anterior end a
Small buccal capsule with 2 leaf crowns
Big buccal capsule with 3 sharp teeth
Big buccal capsule with 2 rounded teeth
Big buccal capsule without teeth
Small buccal capsule with 2 cutting plates
Strongylus vulgaris is a roundworm that infects horses and in the adult stage locates in the large intestine. Adults of S. vulgaris can be identified by
Small buccal capsule with 3 teeth
Small buccal capsule without teeth
Large buccal capsule with 2 ear shaped teeth
Large buccal capsule with 2 sharp teeth
Large buccal capsule without teeth
Genus Strongylus contains important parasites for the health of horses. Horses can become infected with parasites from this genus by:
Ingestion of third stage larvae with pasture and water
Ingestion of hexacanth embryos with pasture or water
Ingestion of metacercaria with food and water
Ingestion of snails with pasture and water
Bites of insects from the genus Culicoides
Genus Strongylus contains important parasites for the health of horses. Eggs shed by animals infected with parasites from this genus are
Thin shelled and contain many cells
Thin shelled and contain a hexacanth embryo
Thick shelled and contain a hexacanth embryo
Thick shelled and contain many cells
Nematode species from the genus Strongylus (S. vulgaris, S. edentates, S. equinus) infect horses and lay eggs that are thin shelled and contain many cells inside (‘strongyle’ eggs). However, thin shelled eggs that contain many cells if found in the faeces of horses younger than 5 months cannot belong to these parasite species because
The eggs of species from genus Strongylus are inside gravid proglottids
The prepatent time of species from genus Strongylus is longer than 5 months
Species from the genus Strongylus do not infect horses younger than 5 months
Larvae hatch during the transit through the digestive tract
Pathology in the horses infected with parasite species from the subfamily Cyathostominae (small strongyles) is usually associated with
Inhibited larvae in the wall of the large intestine
Migration of the larvae through the lungs
Transition of larvae to adults in the large intestine
Synchronous emergence of the larvae from the tissue cysts
Adults that feed on large amounts of blood
What are the characteristics of the super family strongyloidea?
Buccal capsule
bursa well developed
Small mouth
Mouth surrounded by corona radiata (leaf crowns)
Identify this species that belongs to the genus strongylus, superfamily strongyloidea
Strongylus endentatus
Strongylus vulgaris
Strongylus Equinus
Haemonchus
For some nematode parasites species, synchronous reactivation and emergence of large numbers of larvae from the wall of the digestive tract is associated with severe pathology and death of the host. From the following list select the worms that are likely to enter hypobiosis in the wall of the large intestine of the horses and cause severe pathology when larvae resume development and emerge from the wall
Subfamily Strongylinae (large strongyles)
Subfamily Cyathostomine (small strongyles)
Family Oxyuridae (pinworms)
Family Strongiloididae (thredworms)
Subfamily Cyathostomine (small strongyles) contains common worm species that are very important for the health of horses and have a propensity to inhibit development as fourth stage larvae. Which factors might trigger the resumption of development of the larvae and the associated pathology?
Presence of wound or skin areas with moisture
Age and sex of the animals
Pregnancy and lactation
Season and anthelmintic treatments
Larvae of some worm species can stimulate the development of large nodules (visible with naked eye) in the wall of the intestine. Infection with which of the following worm species might be associated with big nodules in the wall of the intestine of the sheep?
Trichostrongylus
Oesophagostumum
Chabertia
Ostertagia
Haemonchus
Larvae of roundworms species from the genus Oesophagostomum have been associated with development of large nodules in the wall of the intestine of sheep, cattle, pigs etc. Adults of the roundworms from the genus Oesophagostomum (nodular worms) are characterized by:
Location in the abomasum and presence of a tooth in the buccal capsule;
Location in the large intestine and presence of a cephalic vesicle;
Location in the small intestine and presence of cutting plates in the buccal capsule;
Location in the small intestine and presence of a cephalic vesicle;
Location in the large intestine and presence of a tooth in the buccal capsule
Big nodules (0.5-1 cm diameter) easily visible on the serosa of the intestine in sheep (as shown in the below photo) are likely to be caused by:
Larvae of Oesophagostomum
Adults of Chabertia ovina
Adults of Oesophagostomum
Adults of Trichuris ovis
Many species of worms locate in the large intestine of the ruminants. Select the genus of the parasites that in the adult stage locate in the large intestine of the ruminants and it is shown in the attached photo.
Strongylus
Trichuris
Trichostrongylus
Oesophagostumum
Chabertia
Chabertia ovina is a parasite from superfamily Strongyloidea (class Nematoda) that infects sheep, locates in the large intestine and feeds by ingesting large plugs of intestinal tissue. Morphological this worm can be identified by:
Big buccal capsule without teeth but with small leaf crowns
Big buccal capsule without teeth but with big leaf crowns
Small buccal capsule without teeth but with big leaf crowns
Small buccal capsule with teeth and small leaf crowns
Big buccal capsule with teeth and small leaf crowns
Fig 1 shows the anterior end of a worm found in the large intestine of a sheep. Select the parasite from the following list
Oesophagostumum columbianum
Chabertia ovina
Ostertagia ostertagi
Haemonchus contortus
Trichostrongylus colubriformis
Stephanurus dentatus is a pig parasite that locates in the pelvis of the kidney and is prevalent in free range systems. Pigs can become infected with Stephanurus dentatus:
Orally by ingesting third stage larvae from environment or paratenic hosts (earthworms) that contain third stage larvae
Orally by ingesting embrionated eggs or paratenic hosts (earthworms) that contain embrionated eggs
Orally by ingesting third stage larvae in milk or paratenic hosts (earthworms) that contain third stage larvae
Via intermediate hosts (ticks and mosquitoes) that inject thirds stage larvae or embrionated eggs
Stephanurus dentatus is a pig parasite that locates in the pelvis of the kidney and is prevalent in free range systems. The most important morphological features used for identification of the adult stage of this worm are:
Stout worms with transparent cuticle and cup shaped buccal capsule
Stout worms with big bursa and cup shaped buccal capsule
Slender worms with big bursa and a cephalic vesicle
Slender worms with big bursa and cup shaped buccal capsule
The photo below shows the anterior end of a parasite that was found in the pelvis of a kidney of a pig from an organic farm. From the list below select the name of the parasite:
Strongylus edentatus
Chabertia ovina
Stephanurus dentatus
Ascaris suum
Oesophagostomum dentatum
Stephanurus dentatus is a pig parasite that in the adult stage locates in the pelvis of the kidney and is prevalent in free range systems. In which organs do the larvae of this parasite spend up to 9 months and cause significant pathology?
Liver
Heart
Pancreas
Lungs
Birds (pheasants, turkeys, chickens etc) can be infected by a roundworm that looks like the letter ‘Y’ and locates in the trachea. This parasite belongs to the genus:
Aelurostrongylus
Angiostrongylus
Dictyocaulus
Syngamus
Syngamus trachea is a nematode parasite (order Strongylida, superfamily Strongyloidea) that can infect birds, locates in the trachea and is prevalent in free range systems. How could the birds become infected with this worm?
ingestion of paratenic hosts that contain third stage larvae;
ingestion of morulated eggs;
ingestion of infective cysts;
Ingestion of paratenic hosts that contain plerocercoid larvae ;
Syngamus trachea is a nematode worm from order Strongylida that can infect birds, locates in the trachea and is prevalent in free range systems. The eggs of this worm are different from the eggs of most species from order Strongylida by:
Having a thin shell
Containing a miracidium
Containing an hexacanth embryo
Being in a morula stage
Having an operculum at each pole
Eggs like those shown in the attached photo were found in the faeces of large numbers of chickens grown in a free range farm. From the list below select the parasite species the chickens are infected with:
Trichostrongylus tenuis
Ascaridia galli
Heterakis gallinarum
Syngamus trachea
Bursa is a bell shaped structure with three lobes supported by rays or papillae. From the following list of parasites that can infect dogs select the worm species whose males have a bursa
Dirofilaria immitis
Ancylostoma caninum
Toxocara canis
Trichuris vulpis
Hookworms (Phylum Nematoda, Order Strongylida, Superfamily Ancylostomatoidea) are blood feeding parasites that infect humans and animals. Morphologically they are characterized by:
Anterior part of the body bent dorsally and presence a large buccal capsule provided with teeth and/or cutting plates
Anterior part of the body bent dorsally and presence of a small mouth surrounded by 3 lips
Anterior part of the body bent dorsally and presence of a small mouth surrounded by a collar
Anterior part of the body bent ventrally and presence a large buccal capsule provided with two leaf crowns (corona radiata);
Ancylostoma caninum is a blood feeding worm that locates in the small intestine of the dogs and other canid species. Adults of Ancylostoma caninum are:
Bent dorsally and have a big buccal capsule provided with 3 pairs of sharp teeth
Bent ventrally and have a big buccal capsule provided with 2 pairs of teeth
Bent dorsally and have a big buccal capsule provided with one pair of cutting plates
Bent dorsally and have big buccal capsule without teeth;
Ancylostoma caninum is a blood feeding worm from family Ancylostomatoidea that infects the dogs and has the anterior end bent dorsally (hookworm) and the buccal capsule provided with three pairs of teeth (see attached photos). Where do the adult parasites locate
heart
small intestine
large intestine
stomach
Identify the species in the image. it is a hookworm that infects dogs
Toxacaris canis
Ancylostoma cati
Ancylostoma caninum
ostertagia
Ancylostoma caninum is a blood feeding worm that locates in the small intestine of the dogs and other canid species. Dogs can become infected with Ancylostoma caninum
Orally and via placenta
Transcutaneously and orally
Transcutaneosly and via placenta
Orally and via tick bites
Larvae of some species of hookworms (Phylum Nematoda, Order Strongylida, Superfamily Ancylostomatoidea) that infect dogs and cats may infect humans and cause
Cysts in the striated muscles
OLM (Ocular Larva Migrans);
CLM (Cutaneous Larva migrans)
VLM (Visceral Larva Migrans);
Hookworms (Phylum Nematoda, Order Strongylida, Superfamily Ancylostomatoidea) are blood feeding parasites that infect humans and animals. Third stage larvae of which hookworm can infect the host via the milk and thus cause severe pathology and death in neonates?
Ancylostoma caninum
Ancylostoma tubaeforme
Ancylostoma braziliense
Bunostomum trigonocephalum
Uncinaria stenocephala
Hookworms (Order Strongylida, Superfamily Ancylostomatoidea) are important parasites for the health of animals and humans. The most common species of hookworms that infect dogs are
Ancylostoma caninum, A. braziliense, A. ceylanicum and Bunostomum phlebotomum
Ancylostoma caninum, A. braziliense, A. ceylanicum and Uncinaria stenocephala
Ancylostoma caninum, A. braziliense, A. ceylanicum and Bunostomum trigonocephalum
Ancylostoma tubaeforme, A. braziliense, A. ceylanicum and Bunostomum trigonocephalum
Ancylostoma tubaeforme, A. braziliense, A. ceylanicum and Uncinaria stenocephala
Detection of eggs in the faeces of animals is a common method to confirm infections with mature parasites. From the photos 1-5 select the egg that is going to be found in the faeces of animals infected with hookworms (order Strongylida, superfamily Ancylostomatoidea).
Photo 5
Photo 4
Photo 3
Photo 2
Photo 1
A paratenic (or transport host) is a host in which the parasite does not undergo any development but in which it remains alive and infective to another host. Paratenic hosts might be a source of infection for which of the following hookworms
Ancylostoma caninum only
Ancylostoma braziliense only;
All of the above mentioned parasite species;
Ancylostoma tubaeforme only
Uncinaria stenocephala only
Bunostomum trigonocephalum is a hookworm that infects sheep and locates in the small intestine. The most important morphological features used for identification of this worm are:
Big buccal capsule provided with two leaf crowns (corona radiata);
Big buccal capsule provided with a dorsal cone (dorsal tooth);
Small buccal capsule without teeth;
Small buccal capsule provided with two pairs of teeth;
Bunostomum trigonocephalum is a blood feeding worm that infects sheep and locates in the small intestine. The sheep can become infected with this worm with:
embrionated eggs orally only
third stage larvae orally only
third stage larvae transcutaneously only
third stage larvae orally and transcutaneously
Identify this species of hook worm that infect dogs and cats
Uncinaria stenocephala
Ancylostoma caninum
Ancylostoma brasilianse
Ancylostoma tuberforme
Identify this hook worm that infects sheep and goats
Ancylostoma caninum
Bunostomum trigonocephalum
ancylostoma brasilianse
What are the characteristics of the superfamily metastrongyloidea (lungworms)
Usually found in the respiratory system
Mouth is small and surrounded by 6 lips
Bursa is small
Single tooth
Large mouth
Protostrongylus rufescens and Mullerius capillaris are two roundworms (class Nematoda) from order Strongylida, Superfamily Metastrongyoidea that locate in the bronchioles and alveoli of sheep and goats. Sheep and goats infected with these lungworms will pass in the faeces:
Microfilaria
Larvae
Eggs with larvae;
Eggs that contain one cell only;
Protostrongylus rufescens and Mullerius capillaris are small size worms that locate in the bronchioles and alveoli of the sheep and goats. How do the animals become infected with these parasites?
Ingestion of third stage larvae from intermediate hosts
Ingestion of third stage larvae from environment
Ingestion of embrionated eggs from intermediate hosts
Ingestion of microfilaria from environment
Ruminants might become infected with many species of roundworms that locate in the lungs. From the list below select the genera of the worms that might locate in the lungs of sheep and goats:
Dictyocaulus, Metastrongylus and Aelurostrongylus
Dictyocaulus, Protostrongylus and Mullerius
Protostrongylus, Mullerius and Aelurostrongylus
Protostrongylus, Mullerius and Metastrongylus
Metastrongylus spp are roundworms that infect pigs and locate in the bronchi and bronchioles. Pigs infected with Metastrongylus spp will shed in the faeces:
Microfilaria
First stage larvae
Embrionated eggs
Eggs that contain one cell
Metastrongylus spp are roundworms that infect pigs and locate in the bronchi and bronchioles. Pigs can become infected with Metastrongylus spp by
Ingestion of infective larvae in the milk;
Ingestion of microfilaria from environment
Ingestion of earthworms that have infective larvae in their body;
Ingestion of eggs that contain infective larvae
Metastrongylus spp are roundworms that infect pigs grown under extensive systems and are transmitted via earthworms. Where do these worms locate within the body of the mammalian host?
bronchi and bronchioles
kidneys and ureters
small and large intestine
stomach and small intestine
Oslerus osleri, a roundworm that infects dogs:
Locates in trachea/bronchi and its first stage larvae found in the saliva or feces are infective for another host;
Locates in trachea/bronchi and its third stage larvae found in the saliva or feces are infective for another host;
Locates in the oesophagus and its third stage larvae found in the paratenic hosts are infective for another host;
Locates in the large intestine and its embrionated eggs found in the environment are infective for another host;
Aelurostrongylus abstrusus is a roundworm that infects cats and locates in bronchiole and alveoli. Which of the following statements is true ?
It does not have intermediate hosts and the cats get infected by ingestion of free infective larvae;
It has snails and slugs as intermediate hosts and the cats most often become infected by ingestion of paratenic hosts;
It has mites as intermediate hosts and the cats get infected by ingestion of paratenic hosts
It has earthworms as intermediate host and the cats get infected by ingestion of free infective larvae;
Aelurostrongylus abstrusus is a roundworm that infects cats and locates in bronchiole and alveoli. Cats infected with this parasite will shed in the faeces:
Embrionated eggs
Microfilariae
First stage larvae
Eggs that contain a hexacanth
Angiostrongylus cantonensis is a worm that infects rats and locates in the adult stage in the pulmonary artery. Humans and dogs can serve as paratenic hosts for this worm. Where do the worms locate in the body of humans and dogs?
Brain and spinal cord
Liver and lungs
Pulmonary artery and heart
Small and large intestine
Parasites from order Ascaridida are characterized by the following:
Large, whitish and stout bodies provided with three lips at the anterior end;
Large, whitish and stout bodies provided with a buccal capsule at the anterior end;
Large, reddish and stout bodies provided with three teeth at the anterior end;
Small, reddish and stout bodies provided with 6 lips at the anterior end;
Eggs of most species of parasites from order Ascaridida are:
Thick shelled and contain 1-2 cells when laid by the female parasites
Thick shelled and contain a larva when laid by the female parasites;
Thin shelled and contain many cells (morula stage) when laid by the female parasites;
Thick shelled and contain many cells (morula stage) when laid by the female parasites;
‘Milk spots’ in the liver of the pigs are likely to be caused by
Larvae of Stephanurus dentatus;
Larvae of Ascaris suum
Immature stages of Fasciola hepatica
Larvae of Hyostrongylus rubidus
Commonly, adult stages of parasites from order Ascaridida:
Locate in the small intestine and feed on blood;
Locate in the abomasum and feed on blood;
Locate in the small intestine and feed on intestinal content;
Locate in the large intestine and feed on intestinal content;
Eggs of which parasite from the following list are known to survive for a long time (years) in the environment?
Ancylostoma caninum
Ascaris suum;
Draschia megatsoma
Thelazia rhodesii
Infection of the hosts with parasites from order Ascaridida can be done by:
Ingestion of sporulated oocysts from the environment
Ingestion of third stage larvae within the intermediate hosts
Ingestion of third stage larvae that are free in the environment;
Ingestion of embrionated eggs from the environment
The eggs in the image from the order ascaridida belong to what species?
Toxocari cati
Ascaris suum
Toxocaris canis
Infection of humans with larvae of Toxocara canis might cause
visceral larva migrans (VLM)
cutaneous larva migrans (CLM);
‘Milk spots’ in the liver
Granulomas (‘Coin’ lesions) in the lungs
Larvae of Toxocara canis can follow either a tracheal migration or a somatic migration after they infect the dogs. Which is the most important factor that determines the type of migration?
Number of adult parasites in the host;
Age of the host;
Size of the infective dose
Season the host gets infected;
From the following list select the ways dogs can become infected with Toxocara canis.
Ingestion of sporulated oocysts or paratenic hosts that contain sporozoites, via ticks and mosquitoes;
Ingestion of the third stage larvae or paratenic hosts that contain thirds stage larvae, via placenta and milk;
Ingestion of embrionated eggs or paratenic hosts that contain third stage larvae, via placenta and milk;
Ingestion of first stage larvae from saliva and faeces, via ticks and mosquitoes;
The lifecycle of Toxocara cati differs from that of Toxocara canis in many respects, one of the most important one being:
Infection with free third stage larvae does not occur;
Infection via placenta does not occur
Infection via milk does not occur;
Infection with embrionated eggs does not occur;
After hatching from eggs in the intestine of the host third stage larvae of Toxascaris leonina and Ascaridia galli will:
Migrate to liver, heart and lungs where they mature;
Migrate to liver, heart, lungs and musculature where they enter hypobiosis
Mature in the small intestine without migration to other organs
Migrate to liver, heart, lungs, pharynx and back to small intestine where they mature;
Ascaris suum is white, stout worm that infects pigs and locates in the small intestine. How do the eggs of this parasite look like when shed in the faeces of the host?
Not coloured, thick and smooth shell and with an hexacanth embryo inside
Yellow-brown, thick and mammilated shell and with one cell inside
Yellow brown, thick and smooth shell and with plugs at both poles
Not coloured, thin shelled with many cells inside
Ascarids are common parasites in young pigs and horses. Pigs and horses can become infected with Ascaris suum and Parascaris equorum, respectively by
ingestion of eggs that contain infective larvae
ingestion of mites that contain cysticercoid larvae;
ingestion of free third stage larvae
ingestion of metacercaria fixed on the grass;
Toxocara vitulorum is a roundworm that locates in the small intestine of the calves. Development of patent infections (infections with adult worms) occurs when the animals become infected:
With larvae from the milk
With larvae from paratenic host
With larvae from the environment
With embrionated eggs from environment
Infections with the ascarid worm Toxocara canis are very common in puppies under the age of 3 months. What are some of the most important morphological features used for identification of this worm?
Whitish, very slender worms (less than 2 mm diameter) with a mouth without lips
Whitish, stout worms (longer than 10 cm) with 3 lips and cervical alae
Whitish, long worms (longer than 1 m) with a scolex and 4 suckers
Reddish, small worms (less than 2 cm long) with a buccal capsule and 3 pairs of teeth
The attached photos show the anterior (A) and posterior (B) ends of worms that were found in large numbers in the small intestine of a 6 week puppy. From the following list select the parasite the puppy was infected with.
Uncinaria stenocephala
Taenia pisiformis
Toxocara canis
Ancylostoma caninum
Toxocara canis is a roundworm that locates in the small intestine of the dogs. How do the eggs of this parasite look like when shed in the faeces of the host?
Dark brown, thick shelled with a finely pitted outer coat and only one cell inside
Yellowih brown, thick shelled with a smooth outer layer and plugs at both poles
Not coloured, thin shelled with a smooth outer layer and many cells inside
Dark brown, thick shelled with a smooth outer layer and only one cell inside
Detection of eggs in the faeces of animals is a common method to confirm infections with mature parasites. Eggs like the one shown in the below photo were found in large numbers in the faeces of all 6 week puppies from a litter. Name the parasite the puppies are infected with.
Toxocara canis
Toxascaris leonina
Ancylostoma caninum
Uncinaria stenocephala
Infections with the mature worms from the species Toxocara canis are very common in puppies under the age of 3 months. How do the puppies become infected with this worm:
with third stage larvae via placenta
with microfilaria found in the intermediate hosts
with third stage larvae found in the intermediate hosts
with free third stage larvae from environment
Identify this species of Ascarid
Toxocara cati
Toxocaris canis
Ancylostoma caninum
Haemonchus
Heterakis gallinarum is a roundworm that locates in the caeca of chickens and turkeys and has earthworms as paratenic hosts. H. gallinarum is important for the health of chickens and turkeys because:
It can perforate the wall of the caeca and cause peritonitis
It grows very quickly and spoliate the host of nutrients
It is vector for Histomonas meleagridis
It feeds on blood and cause severe anemia
The adult stage of the roundworm of Oxyuris equi locates in the lumen of the large intestine while the immature stages locate in the wall of the large intestine. Horses infected with adult stages of Oxyuris equi are likely to show the following clinical signs:
Diarrhoea with mucus and abdominal distension;
Pruritus and rubbing of their rumps against stall fixtures, trees, and fence posts etc;
Icterus and severe muscular pain;
Chronic coughing and dyspnoea;
Oxyuris equi is a roundworm that locates in the large intestine of the horses. Females of Oxyuris equi will usually lay eggs in:
The perianal area;
The cranial mesenteric artery;
The lumen of the large intestine;
The lumen of bronchi and trachea;
Oxyuris equi is a roundworm that locates in the large intestine of the horses and is very common in stabled horses. Eggs of Oxyuris equi are
thin shelled, symmetrical and with a mucoid plug at one end and can be found in the fresh faeces passed by horses;
thick shelled, symmetrical and with two mucoid plugs and can be found in crusts present around the anus of the horses;
thick shelled, asymmetrical and with a mucoid plug at one end and can be found in crusts present around the anus of the horses;
thin shelled, symmetrical and with two mucoid plugs and can be found in the lumen of the large intestine;
Identify this parasite that infects horses
Oxyuris equi
Stonrylus vulgaris
Strongylus edentatus
Ascaris suum
Draschia megastoma is a worm from order Spirurida that infects horses and has muscid flies as intermediate hosts. Which of the following statements is true about Draschia megastoma?
Adults can cause cutaneous habronemosis while the larvae might cause VLM (visceral larva migrans);
Adults cause large nodules in the stomach of the horses while the larvae might cause a skin condition called cutaneous habronemosis
Adults cause blockage of the small intestine of the horses while the larvae cause CLM (cutaneous larva migrans);
Adults cause pruritus and rubbing of the horses’ rumps against stall fixtures and the larvae might cause a skin condition cutaneous habronemosis;
Spirocerca lupi is a roundworm from superfamily Spiruroidea that infects dogs and has dung beetles as intermediate hosts. Where in the body of the definitive host does S. lupi locate?
Adults in the wall of oesophagus and larvae in the stomach and aorta
Adults in the small intestine and larvae in the liver
Adults in the stomach and the larvae in the skin;
Adults in the pulmonary artery and larvae in the skin;
Draschia megastoma is a worm from order Spirurida that infects horses and locates in the stomach where it can cause development of large nodules. The intermediate host of Draschia megastoma is represented by
Copepods
Snails
Flies
Mosquitoes
Gnathostoma spp are stout roundworms that belong to superfamily Spiruroidea and that at the anterior end are provided with a cuticular swelling covered with spines. These parasites can infect a wide range of hosts. Where do the adult stages of the species from the genus Gnathostoma locate?
Oesophagus
Lungs
Stomach
Intestine
Thelazia rhodesii is a whitish roundworm that belongs to superfamily Spiruroidea. The adults of Thelazia rhodesii locate in the conjunctival sac and lacrimal duct of cattle, goats sheep etc. Who are the intermediate hosts of T. rhodesii?
Flies
Mosquitoes
Ticks
Lice
Oxyspirura mansoni is roundworm from order Spiruroidea that locates in the inner corner of the orbit, under the nictitating membrane of the chickens. How do the birds becomeinfected with this parasite:
Third stage larvae are transferred when infected mosquitoes feed on the host;
Third stage larvae within infected cockroaches are ingested by the host;
Third stage larvae are transferred directly from the eye of an infected host to the eye of another bird;
Third stage larvae are transferred when infected flies feed around the eyes of the host;
The posterior end of males in the order spirurida are what?
square
Have spines
Slender
Spirally coiled
Identify this parasite from the order spirurida
Draschia megastoma
Oxyspirura mansoni
Thelazia rhodesii
Parasites from order Filaroidea are best characterized by:
Long, thin worms that locate in blood, body cavities, connective tissue etc and have haematophagous arthropods as intermediate hosts;
Long, stout worms that locate in the stomach, small and large intestine and have direct lifecycles;
Short worms with the anterior end filiform and the posterior one thick and that locate in the large intestine and have direct lifecycles;
Short, reddish worms that locate in abomasum and the small intestine and use snails/slugs as intermediate hosts;
Bleeding nodules on the neck and trunk of horses can be caused by the following parasite:
Parafilaria multipapillosa
Stephanofilaria spp.
Dirofilaria immitis
Parasites from the order spirurida infect canids and located in the oesophagus and cause nodules
Draschia megastoma
Spirocerca lupi
Habronema muscae
Oxyuris equi
Dirofilaria immitis harbours intracellular bacteria that are important in the pathogenesis of heartworm disease. Select the genus these bacteria belong to
Escherichia
Salmonella
Wolbachia
Staphylococus
Pseudomonas
Female of Dirofilaria immitis lay in the blood of the host microfilaria that to develop further need to be ingested by the intermediate hosts represented by:
Mosquitoes from the genera Culex and Aedes;
Ticks from the genera Rhipicephalus and Dermacentor;
Fleas from the genera Ctenocephalides and Echidnophaga;
Tabanids from the genera Tabanus and Chrysops
The prepatent time of Dirofilaria immitis is approximately:
7 months
1 week
1 month
2 weeks
Adults of Dirofilaria immitis can locate in the pulmonary artery, right ventricle, right atrium and the caudal vena cava. Which are some of the most important factors that determine the location of the parasites?
intermediate host and sex of the dog;
intermediate host and the immune response of the host;
sex of the dog and worm burden;
size of the dog and worm burden
Onchocerca cervicalis is a roundworm that
infects cattle, locates in the funicular portion of the ligamentum nuchae and it is transmitted by Simulium spp;
infects horses, locates in the subcutaneous tissue of the skin and it is transmitted by Musca spp
infects horses, locates in the funicular portion of the ligamentum nuchae and it is transmitted by Culicoides spp
infects dogs, locates in the funicular portion of the ligamentum nuchae and it is transmitted by Aedes spp;
Onchocerca gibsoni is a parasite common in cattle from Northern Australia that:
Locates in nodules in the brisket and it is transmitted by Culicoides spp
Locates in nodules in the skin and it is transmitted by Musca spp;
Locates in the subcutaneous tissue of the skin and it is transmitted by Haematobia spp;
Locates in the conjunctival sac and lacrimal duct and it is transmitted by Musca spp;
Trichinella spirallis is a roundworm that infects a wide range of hosts. Where do the parasites locate?
Adults locate in the musculature and the larvae in the small intestine;
Adults locate in the blood and the larvae in the musculature;
Adults locate in the small intestine and larvae in the musculature;
Adults locate in the small intestine and the larvae in the blood;
How do the hosts get infected with Trichinella spirallis?
ngestion of meat that contain infective larvae;
Ingestion of infective larvae from environment;
Ingestion of embrionated eggs;
Ingestion of paratenic hosts that contain infective larvae;
How long can the larvae of Trichinella spiralis remain infective in the host?
Up to 2 days
For the life of the host
Up to 2 months
Up to 6 months
Trichuris spp are roundworms that infect many host species. Where do the worms locate?
The adult parasites locate in the large intestine with the thin part of the body embedded in the mucosa
The adult parasites locate in the large intestine with the thick part of the body embedded in the mucosa;
The adult parasites locate in the small intestine with the buccal capsule fixed in the mucosa;
The adult parasites locate in the large intestine with the buccal capsule fixed in the mucosa;
How do the hosts get infected with Trichuris spp?
Ingestion of embrionated eggs;
Via the milk with reactivated larvae;
Transcutaneously with free larvae from environment;
Ingestion of free larvae from environment
Eggs of Trichuris spp that are found in the faceal samples are:
Not coloured, thin shelled and with a larva inside;
Not coloured, thin shelled and with many cells (morula) inside
Yellow-brown, with thick and smooth shell, plugs at poles and only one cell inside and look like a lemon
One of the most important morphological differences between species from genus Trichuris and Capillaria is
The transition between the anterior, filiform portion and the posterior, thick portion is gradual in Capillaria and abrupt in Trichuris;
Trichuris has a buccal capsule with teeth while Capillaria does not;
Males of Trichuris have one spicule only while those of Capillaria have 2 spicules;
Males of Trichuris have a copulatory bursa while those of Capillaria do not have;
Dirofilaria immitis is a nematode that infects dogs and cats and locates in the pulmonary arteries and right ventriculum. How do the dogs become infected (stage of the parasite and way of entry into the host) with this parasite?
L3 from fleas, ingestion of fleas
L3 from mosquitoes, deposited on the body of the host by mosquitoes;
L3 from ticks, injected with tick saliva;
L3 from environment, ingestion with food or water
Strongyloides spp. might cause damage to the host
At the site of penetration of the skin, during migration through the lungs and during the enteric stage
At the site of penetration of the intestine, during migration through the kidneys and during the enteric stage
At the site of penetration of the skin, during migration through the mammary gland and during the enteric stage;
At the site of penetration of the intestine, during migration through the liver and during the enteric stage
Spirocerca lupi is a dog parasite that locates in:
Adults in the pulmonary artery and larvae in the skin;
Spirocerca lupi is a dog parasite that locates in:
Adults in the small intestine and larvae in the liver;
Adults in the stomach and the larvae in the skin;
