Lab Final Flashcards
What are cestodes?
Tapeworms, dogs and cats are the definitive hosts, but they can be zoonotic
What are the different kinds of cestodes?
- Dipylidium canium
- Echinoccus spp
- Taneia spp
How my tapeworms be transmitted to humans?
Children may ingest via the mouth or people who sleep with infected pets
What is the definitive host?
The reproductive cycle host
What is the end stage host?
Not a typical host and the parasite will die
What is the most common intermediate host of the tapeworm?
Ctenocephalids felis
What is the prepatent period?
Time period prior to parasitic reproduction
Will Dipylidium caninum eggs be visible on a fecal float?
Not necessarily, because the eggs are heavy; think cucumber seeds
What are the parts of the tapeworm body?
- Scollex: head of the tapeworm
- Proglottid: segments behind the head
Which tapeworm is typically transmitted through infected stool?
Dipylidium caninum
What is the intermediate host of Echinococcus spp?
Mammal due to grass eating
What is the intermediate host of Taenia spp?
Small mammals making it the most common tapeworm of the cat
What is the prepatent period of Dipylidium caninum?
14-21 days
What is the prepatent period of Echinoccus spp?
47 days
What is the prepatent period of Taenia spp?
36-42 days
What are nematodes?
Any sphere shaped worms including hookworms, roundworms, threadworms, whipworms, and heartworms
Are nematodes zoonotic?
All except whipworms
Which species of hookworms only affect the dog?
Ancylostoma caninum
What species of hookworms only affect the cat?
Ancylostoma tubaeforme
What is the most common parasite of the dog?
Roundworms
How do children typically get roundworms?
Poor hygiene
What may humans develop from having hookworms?
Cutaneous larval migrans
What may humans develop from having roundworms?
Visceral or ocular larval migrans
Which nematode is the most dangerous to humans?
Racoon roundworms, which is why most heartworm prevenatives prevent against racoon roundworms
What is the prepatent period for hookworms?
15-18 days
Which parasites do puppies and kittens get dewormed for?
Hookworms and roundworms
Why are hookworms called such?
The adults have ventral teeth that hook onto the small intestine and suck blood
All endoparasites except which live in the small intestine?
Whipworms
Which stage of hookworm larvae are the infective stage?
The 3rd stage
What are the routes of transmission for hookworms?
- Direct ingestion of infected feces
- Transdermal penetration of paw pads
- Transplacental or transmammary
Which roundworm has the longest prepatent period?
Toxascaris leonina - 74 days
What is the prepatent period for Toxocara canis?
28-35 days
What are the routes of transmission for Toxascaris leonina?
Direct or indirect ingestion
What are the routes of transmission for Toxascaris canis?
- Direct or indirect ingestion
- Transplacental or transmammary ingestion
What are the routes of transmission for Toxascaris cati?
- Direct or indirect ingestion
- Transmammary ingestion
What is the first worm an animal can transmit after being born?
The threadworm due to its fast prepatent period of only 5-7 days and is only seen on a Baerman sediment technique
Why are whipworms so difficult to see on a fecal float?
Because they don’t float well and usually sink and have a prepatent period of about 3 months
How are whipworms transmitted?
Eggs are shed intermediately in feces and then eggs are ingested
What are protozoa?
Giardia, Cystoisospora spp and Toxoplasma gondii
Which protozoa only affect the dog and cat?
Coccidia, Giardia and Toxoplasmosis are zoonitic
What is the infective stage of Giardia?
Cysts which are best seen with iodine, while adults are best seen on a zinc sulfate float
What is the common name for Giardia?
Beaver fever
How is Giardia transmitted?
Direct ingestion of cysts
What is the infective stage of Coccidia?
The sporulated stage, when the cell has 2 nuclei, which typically happens in a perpatent period or 3-11 days
How is Coccidia transmitted?
Eggs are passed in feces, then develop into sporulates , then ingestion either directly or indirectly by an intermediate host
What is the prepatent period of Toxoplasmosis?
3-24 days
How can humans be exposed to Toxoplasmosis?
By ingesting undercooked meat or handling feces of feral cats
How are cats infected with Toxoplasmosis?
Through both direct and indirect ingestion
What is the most prevalent flea of all species, but most commonly effects the dog?
Ctenocephalides felis
What is the rat flea called?
Xenopsylla cheopis which transmits the Black Plague
What is the name of the Gram-negative, rod shaped bacteria that transmits the Black Plague?
Yersinia pestis
How many stages are in the flea life cycle?
Larva stage, pupa stage, and adult stage
What is the first feeding stage of the flea?
The larva stage, which are maggot like and covered in small hairs that feed on blood in flea feces, organic debris, flea eggshells and other flea larvae
How are flea eggs transmitted?
They are deposited on the host and readily fall into the environment within a few hours, then eggs hatch in 2-10 days
What controls the speed of development from flea larvae to pupae?
Temperature and humidity, usually in undisturbed protected sites such as carpets, under furniture and along baseboards; not typically outside due to sunlight exposure
Where do flea larvae typically go through metamorphosis?
Cocoons can be found in soil, vegetation, in carpets, under furniture and on animal bedding
How long after metamorphosis can adult fleas begin emerging?
Between 8-14 days after initial pupal development once their environment reaches 24C (745.2F) and 78% relative humidity
How long can delayed emergence for fleas last?
Up to 30 weeks at 11C (51.8F) and 75% relative humidity without environmental stimuli
What are some environmental stimuli that can trigger flea emergence?
Mechanical pressure or vibrations, CO2 exhaled from possible hosts or increased environmental temperatures
When does flea egg production begin?
Within 20-24 hours of females taking their first blood meal and they can produce 40-50 eggs per day
How long can fleas survive?
10 days at 3 C (37.4F), 5 days at 1 C (33.8), and without a host they die within 1-2 weeks
What causes flea allergy dermatitis?
Hypersensitive to antigenic material from the salivary glands of fleas
How many tick life stages are there?
Egg stage, larval stage, nymphal stage, and adult stage
What is the first feeding stage of the tick?
In about two weeks when eggs hatch, the larval stage move into grass or shrubs in search of their first blood meal
What is questing?
When a tick attaches their 3rd and 4th set of legs to a leaf or branch while its front legs wait for something to attach to
Which tick stage has the highest change for disease transmission?
The nymphal stage because they are small and often go undetected; disease typically starts transmitting after 24 hours of attachment
Which gender of the adult tick feeds on a host?
Females will feed, then fall off and mate and lay her eggs in a secluded place
How do topical ectoparasiticides work?
They spread rapidly over the hair coat within 24-48 hours, the skin distributes the agent and it is stored in the sebaceous glands
Which ectoparasiticides does the FDA authorize?
If it is taken internally or has internal actions
Which ectoparasiticides does the EPA authorize?
If it is applied externally with no internal affects
What are macrocyclic lactones?
Capable of killing both endo and eco parasites, it controls locomotion and feeding
What are some examples of macrocyclic lactones?
Avermectins such as Selemectin and Ivermectin, and Milbemycins
What parasites do macrocyclic lactones control?
Nematodes, insects and arachnids
What are tetrahydropyrimidines?
They depolarize the neuromuscular blocking agents of parasites
What is the most commonly used tetrahydropyrimidine?
Pyrantel
What is benzimidazoles or probenzimidazoles?
It stops microtubules assembly in the parasite
What is an example of a benzimidazole/probenzimidazole?
Fenbendazole or oxibendazole
How does feces get it dark brown color?
From stercobilin, with out it, it can appear gray and is referred to as acholic.
Why may feces of meat eaters be stinky?
Due to the typtophan in high protein meals, cats especially because of their intake of indole and skatol
How can a potent feces be treated?
With more carbs and milk proteins rather than meat
How might the feces smell of an animal with maldigestion or malabsorption?
Acidic or sour; nutrients are not getting absorbed so they are rotting in the GI tract
What is malassimilation?
A variety of diarrheal syndromes that result from incomplete absorption of the diet
What are the two basic mechanisms of malassimilation?
Maldigestion and malabsorption
What may the feces from animals with maldigestion typically contain?
May contain large quantities of undigested fat, protein and starch which can be identified by appropriate
What is maldigestion?
No breakdown of nutrients, therefore it is the main cause of diarrhea
What is malabsorption?
Food is broken down in the body, but it is not being absorbed
What is steatorrhea?
Fat in the stool
What is creatorrhea?
Muscle tissue/protein in the stool
What is amylorrhea?
Carbs in the stool
Will an animal with maldigestion also have malabsorption?
Yes, but they may not necessarily have maldigestion if they have malabsorption
What stain is used to test for steatorrhea?
Sudain stain III, direst tests for maldigestion and indirect tests for malabsorption
Which stain is used for creatorrhea?
New methylene blue
Which stain is used for amylorrhea?
Lugol’s Iodine 2%
What is used to evaluate proteolytic activity?
Radiographic film test, geleatin tube test or a baerman test which tests for things that don’t float
What is a culture media?
It is used tor grow bacteria
What is a nutrient agar?
A basic culture medium used to grow certain types of bacteria
What is a blood agar?
Enriched medium that supports growth of most pathogenic bacteria
What is a MacConkey agar?
Selective medium containing bile used for isolation of enterobacteria and some other Gram-negative bacteria
What is a Selenite Broth/Rappaport?
Used for isolation of salmonella from samples containing other Gram-negative bacteria
What is Edwards medium?
A blood agar based selective medium used for the isolation and recognition of Streptococci which is found in the throat and airways
What is Chocolate medium used for?
A heat treated agar which supplies special growth requirments to Factors V & X for the isolation of Hemophilius spp and Taylorella equigenitalis
What is Brilliant Green agar?
Indicator medium for the presumptive identification of Salmonella which gives a bright green color for a positive reaction
What color does Gram-positive bacteria stain?
They are stained blue by the crystal violet color retained in the cell wall; herbivores
What color does Gram-negative bacteria stain?
They are counterstained red; carnivores
What is Giemsa used for?
For finding Dermatophilis, Rickettsiae, and Borrelia, which all stain blue
What is dilute carbol fuschin used for?
Stains red for Campylobacter, Brachyspira, and Fusobacterium
What is polychrome methylene blue used for?
To identify anthrax is blood smears, it will stain blue with distinctive pink capsule within
What stain is used to find TB?
Ziehl-Neelsen
