Lab Written Final Flashcards
What is the most common pinworms of the mouse?
Syphacia obvelata; also found in the rat
What is the most common pinworm of the rat?
Syphacia muris
What is another type of pinworm that may be seen in the mouse and rat?
Aspiculuris tetrapetera
What type of pinworm may be found in the hamster?
Syphacia mesocricetus
What type of pinworm may be found in the gerbil?
Denstomella translucida
What is the typical life span of the pinworm genus Syphacia?
11-15 days
Where are Syphacia eggs deposited in?
The perianal region
How long until Syphacia eggs become infectious?
- Within 6 hours and may survive for weeks- Eggs are lightweight and therefore have the ability to become aerosolized
What are the 3 possible routes of infection of Sphacia pinworms?
- Direct - when an animal ingests the eggs - Indirect - when food or water is contaminated- Retroinfection - when the larvae migrate into the colon
What is the typical life cycle of the pinworm genus Aspiculuris and Denstomella?
23-25 days
When do Aspiculuris/Denstomella eggs become infections?
After 6-7 days and may survive for weeks
Where are Aspiculuris/Denstomella eggs deposited?
In the colon and then expelled with feces
How are A/D pinworms infected?
By direct and indirect ingestion of eggs
What are some signs of pinworm infection?
- Usually subclinical- Rough haircoat- Reduced growth rate- Fecal impaction- Rectal prolapse- Intussusception
What is the morbidity and mortality of the pinworm?
Morbidity is high and mortality is rare
Are males of females more likely to be heavily parasitized by pinworms?
Males
At what life stage do rodents have the highest rate of parasite load?
Weanlings; pinworm number decreases with age of the host
How can pinworms be diagnosed?
- For adults, a direct exam of cecal or colonic contents- Eggs may be seen in a fecal floatation or a tape impression test; however this is not useful in finding A or D pinworms
How are pinworms treated?
- Fenbendazde (Panacur) medicated feed- Ivermectin in water
How can pinworms be controlled?
- NOT by routine disinfection- Quaternary ammonia (Rocal) must be used to clean- Chlorhexidine- 60-90% ethyl or isopropyl alcohol
What are lice and fleas considered?
Insects
What are ticks and mites considered?
Arachnids
What are some characteristics of insects?
- Body comprised of 3 segments: head, thorax and abdomen- 6 legs at adult stage- Compound eyes and antennae- May have wings- Mandibles- Undergo some form of metamorphosis
What are some characteristics of arachnids?
- Body comprised of 2 segments: cephalothorax and abdomen- 8 legs at the adult stage- Simple eyes- No antennae or wings or metamorphosis- Extensions off of the mouth called chelicerae
What kind of lice sucks?
Anoplura
What kind of lice bites?
Mallophaga
Are lice species specific?
Yes
What kind of lice do rats get?
Polyplax spinulosa
What kind of lice do mice get?
Polyplax serrata
What is the typical life cycle of lice?
They live their entire life cycle on their host, usually about 14-21 days
What are the stages of the lice/mite life cycle?
- Eggs (nits)- Nymph- Adult
How are lice or mites transmitted?
Either by direct contact of through fomites (transfer from an inanimate object)
Are mites species specific?
No
What kind of fur mites do mice get?
- Myobia musculi- Myocoptes musculinus- Radfordia affinis
What kind of fur mites do rats get?
Radfordia ensifera
What are some signs that a rodent may have fur mites?
- Patchy alopecia- Skin lesions or ulcerations
Where can burrowing mites be found?
On the ear pinna, tail, nose, or extremities
What is the name of the ear mange mite of the rat?
Notoedres muris
What is the name of the dog ear mite?
Octodectos cynotis
What is the name of the rabbit ear mite?
Psoroptes cunniculi
What is the name of the blood sucking mite of the rat?
Orhthonyssus bacoti; they are zoonotic and may cause anemia
What is the typical life cycle of the mite?
One week
How can mites be treated?
- Ivermectin- Pyrethics (<0.15%) - natural- Chrysanthemum - Disinfect cage with bleach
What types of solutions should be used for fecal floats?
- Sodium sulfate- Sucrose- Zinc sulfate
Which solution is best to see giardia?
Zinc sulfate
What is the Specific Gravity of a solution used for a fecal float?
At least 1.2
What is vaginal cytology?
A simple technique that can be used to help determine the sage of the reproductive cycle of the animal
What is vaginal cytology usually used in conjunction with?
- Physical exam- Clinical history- Vaginoscopy- Hormonal assays
When is a vaginal cytology especially important?
If artificial insemination has been performed
What are some other used of vaginal cytology?
- Determine whelping date (day 57 of diestrus)- Diagnosis of inflammation of the vagina- Identification of some types of neoplasia
What is a basal cell?
The youngest cells of the vaginal epithelium and serves as a precursors of the other epithelial cell types
Where are basal cells located?
Along the basement membrane and therefore rarely seen in exfoliative cytology and should not be seen on a vaginal smear
What is the nucleus to cytoplasm ratio of a basal cell?
The ratio is high and the cell has a high round nucleus and a basophilic cytoplasm
What is a parabasal cell?
The smallest vaginal epithelial cells seen in cytologic preparations
What is the nucleus to cytoplasm ratio of a parabasal cell?
The ratio is high and the cell has a round nucleus and basophilic cytoplasm; the cell is also uniform in size and shape
What are foam cells?
Cytoplasmic vacuoles that may be seen within parabasal cells that have no known function; large numbers of foam cells may be found in prepubertal samples
What are intermediate cells?
Usually about 2x the size of a parabasal cells that may be classified as transitional or superficial cells according to their stage in the reproductive cycle
What is the nucleus to cytoplasm ratio of an intermediate cell?
The ratio is decreased and they have large amounts of blue/green keratinized cytoplasm with borders that are round to irregular and folded
What is a superficial cell?
The oldest vaginal epithelial cell
What is the nucleus to cytoplasm ratio of a superficial cell?
They either have a small, round pyknotic nuclei or lack a nucleus completely if they have been cornified
What is in the cytoplasm of a superficial cell?
Their cytoplasm is abundant, blue green and keratinized, as well has the cell margins are angular with folded edges
What are the 4 types of vaginal cells in order of oldest to youngest?
- Superficial cells- Intermediate cells- Parabasal cells- Basal cells
What are the 4 stages of estrous?
- Proestrus- Estrus- Diestrus- Anestrus
What can the 4 stages of estrous be grouped into?
- Follicular phase (proestrus and estrus)- Luteal phase (diestrus and anestrus)
What is proestrus?
- When the female is getting ready to become pregnant- The vulva becomes increasingly swollen and turgid
What happens to the cells during proestrus?
- Epithelial cells are all non-cornified basal cells and parabasal and intermediate cells gradually decrease in number- Superficial cells appear by 2nd or 3rd day and increase in number over time- Erythrocytes are numerous and gradually decrease in number- Neutrophils disappear by the last day or 2 of proestrus and intermediate cells begin to dominate
What is estrus?
- The female is resceptive to breeding- The vulva suddenly becomes soft and pliable at the beginning of estrus, and gradually shrinks as estrus progresses
What happens to the cells during estrus?
- Mostly large flat angular cornified epithelial cells that become wrinkled and irregular as estrus progresses- Red cells may be observed microscopically- Leukocytes appear on the last day or 2, and a large number indicate the end of estrus and the end of breeding
What is diestrus?
- The period of sexual inactivity- The vulva quickly shrinks to normal anestrus size
What happens to the cells during diestrus?
- Abrupt decrease in superficial epithelial cell numbers- Marked increase in basal and parabasal epithelial cell numbers, as well as neutrophils, also though there is a gradual decrease in 1-2 days- RBC may be present
What is anestrus?
- Period of sexual inactivity- Vulva shows no evidence of swelling and there is no vaginal discharge
What happens to the cells during anestrus?
- Parabasal and basal epithelial cells predominate with scattered neutrophils and lymphocytes are present
What hormonal changes occur during proestrus?
Estrogen increases leading to vulvar edema and swelling with some bloody discharge
What hormonal changes occur during estrus?
LH and progesterone increaseswhile estrogen decreases resuting in less vulvular edema with a more clear discharge
What hormonal changes occur during diestrus?
Progesterone increases while vulvular edema and discharge decreases
What hormonal changes occur during anestrus?
Progesterone decreases resulting in almost no secretions or discharge
