pt 6 (mouse)

Question 1

what is the genus of mouse

Answer 1

mus musculus

Question 2

describe 5 strains of mice commonly used in research and name characteristics

Answer 2

white swiss
C57 - agressive
hairless - have eyelashes
nude - athymic have no t-cells
SCID - no t- or b-cells

Question 3

describe the estrus cycle, gestation, and weaning age of a mouse

Answer 3

estrus cycle - 5 days
gestation - 19 days
weaning - 21 days

Question 4

are mice altricious or precocious? and what do those terms mean?

Answer 4

altricious - babies need a lot of care

Question 5

lee-boot effect

Answer 5

females are housed in groups synchronize estrus cycles; absence of male pheromones lead to anestrus

Question 6

whitten effect

Answer 6

female can be induced into estrus by exposure to male mouse urine

Question 7

bruce effect

Answer 7

pregnant females exposed to a strange male during the first four days of gestation will block the first pregnancy, reovulate

Question 8

how can you tell a female mouse has been bred?

Answer 8

a vaginal plug stays in the vagina 12 hours after mating

Question 9

a mouse is bred on postpartum heat, what is the effect of this?

Answer 9

delayed implantation occurs and increases gestation period 25-30 days

Question 10

what is the term used to describe the time of day when mice are most active?

Answer 10

crepuscular - twilight to dawn

Question 11

what causes ringtail and what are the symptoms?

Answer 11

improper humidity; annular constrictions on the tail leading to necrosis and sloughing

Question 12

what is barbering and how is it treated?

Answer 12

when mice chew the hair off of their cage mates; separate the mice

Question 13

what etiologic agent causes LCM? signs and treatment?

Answer 13

virus; acute death, hunched, rough coat, emaciated; no treatment - prevent by disease-free breeding stock

Question 14

what is another name for mouse typhoid? signs and treatment?

Answer 14

salmonellosis; diarrhea and many are diagnosed by fecal cultures; eliminate infected animals

Question 15

what is a disease other than salmonellosis that causes diarrhea in mice?

Answer 15

tyzzer’s disease

Question 16

how is tyzzer’s disease diagnosed on necropsy?

Answer 16

liver lesions

Question 17

what are the symptoms of respiratory disease in mice? 3 common etiological signs?

Answer 17

chattering, weight loss, unthrifty appearance, head-tilt or circling; mycoplasma, sendai virus, pneumonic virus of mice

Question 18

3 possible treatments for an outbreak of respiratory disease in a room full of mice?

Answer 18

antibiotics, let disease run its course, or depopulate

Question 19

name a zoonotic disease one can contract from mice

Answer 19

lymphocytic choriomeningitis virus

Question 20

what ectoparasites are common in mice?

Answer 20

fur mites
polyplax lice
demodectic mange

Question 21

name 2 endoparasites of mice that you might see on fecal float - should you also do a direct smear? describe procedure

Answer 21

pinworm and tapeworm;

Question 22

what are the 2 pinworm species commonly found in mice?

Answer 22

syphacia and aspicularis