rodents Flashcards
T or F: rodents are the most numerous of all mammalian species
true
are rodents herbivorous, omnivorous or carnivorous?
can be either herbivorous or omnivorous
why do rodents have nocturnal habits and most have rapid flight?
because they are subject to predators
what do rodents gain due to their nocturnal habits
good sense of smell and hearing ( due to their lack of vision)
what does it mean when someone says rodents are on the fast track?
they develop rapidly, reproduce quickly and have a short lifespan
what is the sexual maturity, gestation and lifespan of small rodents ( gerbils, rats and mice)?
sexual maturity - 6-10 weeks
Gestation - 3 wks
lifespan- 1-3 yrs (mouse: 1.5-2.5 yrs , rat: 2.5 - 3.5 yrs)
what is the gestation and lifespan of guinea pigs?
gestation - 2-2.5 months
lifespan - 8 yrs
what is the gestation and lifespan of chinchillas?
gestation - 3.5 months
lifespan - 18 yrs
what is the largest known rodent species?
Capybara (66 kg) most rodents weight less than 100g
why are rodents prone to heat stress?
have no sweat glands and cannot pant
T or F mice are coprophagic but mice are not.
false they are both corporphagic
they need to do this because their feces contain nutrients produced by colonic bacteria
common name for Mus musculus is
house mouse
common name for Rattus norvegicus is
Norway rat
T or F rats and mice are not social but can be very intelligent
false they are social and active intelligent
why do most labs like to keep mice and rats around for research instead of other species?
they are adaptive, small reproduce rapidly extensive genetic characterization over 1000 inbred and outbred strains thousands of genetic mutants
you have a new client bring there mouse into your clinic due to it not acting right. what are somethings you need to tell them when they bring it in?
bring animal in its home cage
need to make an evening appointment
do not clean their cage before coming
why is it better to feed rodents a pelleted diet vrs a mixed diet?
because they are selective eaters and may only eat one ingredient
what is the best way to perform a physical exam on rodent?
observe in cage it’s: posture, grooming activity, respiration and if it is acting depressed.
if it is dyspneic need to handle carefully and caution the owner.
what to most rodents do when you handle them?
they urinate and defecate, so be prepared to collect samples
in small rodents what diagnostics do you usually do with the blood you collect?
PCV and smear - because you can only collect a small amount of blood
in large rodents what diagnostics do you usually do with the blood you collect?
CBC and chem - because you can usually get a higher quantity of blood in large rodents compared to small rodents.
where do you collect blood from a rodent?
lateral tail vein
lateral saphenous vein
you prick the vein and use a hematocrit tube(small or large) to collect it or a small green top tube (large)
what is the normal temperature for a rat? A mouse?
rat - 99.5-100.6
mouse - 98 - 101
what are some signs of illness in rodents?
weight loss Hunched posture Lethargy rough hair coat rapid or labored breathing closed or squinted eyes perineal staining or stain around the eyes
If a rodent bites you what should you not do?!!!
don’t drop it or throw it across the room!! Clients will not like you!!
how do you hold/restrain a mouse?
scruff whole body and stabilize tail with ring or little finger (one handed)
or you can scruff the neck with one hand and stabilize the base of the tail with the other
how do you hold/restrain a rat?
place two fingers behind jaws/ears
one finger in front of leg and one finger behind leg
with other hand stabilize base of the tail
IF YOU PICK THEM UP BY THE TAIL THEY WILL TURN AND BITE YOU!!!!
what will happen in you pick a mouse or rat up by the end of the tail?
there skin might slough off - called tail degloving injury
why you handle them by the base of the tail
they may also bite you
what would happen if you put two adult, unrelated male rodents in together?
they will fight to the death, can be very aggressive. except with hamsters : females tend to be more aggressive.
what can you do to decrease aggression in rodents
raise littermates together or introduce them at weaning
introduce animals in clean cage ( no pheromones and neutral territory)
provide hiding places
observe closely for first few days
what are some ways you can give medications to rodents
orally with ball ending dosing needles (gavage needles) 20 gauge in rats and 22 gauge in mice
intraperitoneal or subQ ( IV injections are difficult)
how much oral medication can you give to rats? mice?
1 ml rats
0.1 ml in mice
where do you give subQ injections in rodents and how much can you give
flank or intrascapular
5 ml in rats
1 ml in mice
where do you give intraperitoneal (IP) injections in rodents and how much can you give?
lateral aspect of the lower left abdominal quadrant with the rodents head slanted downward
5 ml rats
2 ml mice
if you have to give an IV injection in a rodent what can you do to the lateral tail veins to make it easier
dilate vessels with warm water or a heat lamp ( any heat source)
T or F rodents incisors grow continuously, but the upper incisors are longer than the lower incisors. Do not clip them.
false. they do grow continuously, but the lower incisors are longer than the upper incisors