Kangaroo Rats: Dipodomys, Pack Rats: Neotoma, Grasshopper Mice: Onychomys

Dipodomys spectabilis and D. merriami

The two species generally studied are Dipodomys

spectabilis (Bannertail kangaroo rat) and D. merriami

(Merriam’s kangaroo rat). Dpo / stands on two feet

What is the family of Heteromyidae?

Kangaroo rat

What species is this?

Dipodomys spectabilis, kangaroo rat

What is the long tail for in the kangaroo rat?

The tail is longer than the head and body and

serves as a balancing organ in locomotion and as a

prop when standing.

What anatomical feature of Dipodomys is unique amongst Heteromyadae?

Dipodomys are unique in the Heteromyidae

because their cheek teeth grow throughout life; the

cheek teeth of other genera of Heteromyidae do not.

What do geomyidae and heteromyidae have in common regarding their cheek pouches?

They are fur lined

Where are kangaroo rats endemic to?

North America

What are kangaroo models for?

1. Kangaroo rats have been used extensively in the study

of renal physiology and water conservation.

2. been used in investigations

   looking at disuse osteoporosis

3. evolutionary neuroanatomy

4. decompression sickness

5. climate change

6. as biosentinels for environmental contamination by mining operations

Kangaroo rats and goats are what similar models for?

decompression sickness

Is the dorsal gland on kangaroo rats androgen dependent or independent?

The dorsal gland, a prominent

androgen-independent, oil-secreting gland, is present on

the back between the shoulders of males and females

Activity, estrus, gestation and need to drink water for kangaroo rats?

Diurnal, seasonally polyestrus, 29-33 day gestation, do not

recommend ad libitum water, as some kangaroo rats

become addicted to drinking and develop a diabetes

insipidus-like syndrome. Gestation lasts approximately

29–33 days.

Are kangaroo rats easy to breed?

No very territorial and difficult to breed in the laboratory because of

their aggressive nature toward one another. However,

they are not aggressive toward humans. During periods of

nonreceptivity, female kangaroo rats are extremely

aggressive toward males and will frequently attack

and sometimes kill cage mates

Diets of kangaroo rats?

The diet in the laboratory is usually grains

and seeds with lettuce as a source of water

What do kangaroo rats and chinchillas have in common for husbandry practices?

require dust baths

Should you restrain kangaroo rats by the tail?

Nope tend to break off

Which mammals need dust baths?

Kangaroo rat

Chinchilla

Grasshopper mouse

Degu

Japanese Quail

Gerbils

sand rats

What type of degenerative disease do kangaroo rats get and what other rodent is this similar to?

Kangaroo rats develop spongiform degeneration of

the central auditory system, particularly in the cochlear

nucleus and auditory nerve root. The lesions are similar

to that seen in the Mongolian gerbil.

What happens when kangaroo rats are exposed to modest levels

of low-frequency noise <75 dB SPL?

Kangaroo rats develop spongiform degeneration of

the central auditory system, particularly in the cochlear

nucleus and auditory nerve root.

Neotoma floridana

Allegheny wood rat or pack rat

Neotoma albigula

white throated wood rat

Neotoma mexicana

Mexican wood rat

Neotoma cinerea

bushy-tailed wood rat

Neotoma fuscipes

dusky footed wood rat

Common research uses for pack rats (Neotoma):

Wood rats have been used in behavioral and neurological

studies (Towe and Harrison, 1993; Williams,

1980). Additionally, their role as reservoirs for a variety

of zoonotic disease agents has been examined, including

endemic murine typhus (Rickettsia typhus) (Worth, 1950),

trypanosomiasis (Chagas disease) (Charles et al., 2013),

Bartonella spp. (Morway et al., 2008), and Leishmaniasis

(McHugh et al., 1996). Wood rats have been identified as

mammalian hosts for plague (Yersinia pestis) in British

Columbia and California (Davis et al., 2008; Lewis, 1989;

Mian et al., 1996). N. fuscipes is an important mammal reservoir

of Lyme disease (Borrelia burgdorferi) in California

and Oregon (Burkot et al., 1999) and of human granulocytic

ehrlichiosis (Ehrlichia phagocytophila).

Sin nombre virus (hantavirus) has been identified in four

species of Neotoma.

What 3 species have a hemorrhagic factor that makes them more immune to western rattle snake venom?

An antihemorrhagic factor in the serum of N. micropus

against western rattlesnake venom has been identifie

and found similar to that in hispid cotton rat (Sigmodon

hispidus) and in opossum (Didelphis virginiana) sera

Activity, estrus, social structure, gestation or neotoma spp?

nocturnal, breed all year long, solitary animals, gestation length is 30 - 40 days

Do pack rats carry young on nipples and in general what is the anatomic characteristic of pups that enable nipple attachement in certain rodents?

The incisor teeth of nursing pups

are laterally divergent for the first 2 weeks of life, and

the mother’s nipple fits into the gap

Diet of neotoma spp.

In captivity, wood rats can be successfully maintained on standard laboratory rat diets fed fresh fruits and vegitabbles as well

How should neotoma get their hydration?

ad libitum water

Onychomys torridus and O. leucogaster

Grasshopper mice

Which rodent is carnivorous?

grasshopper mouse

What species is this?

Onychomys leucogaster

What species is this?

Onychomys torridus

How do you differentiate O. torridus from O. leucogaster? What is an anatomic characteristic they share but is distinctive within Onychomys?

The dorsal coat of O. torridus is gray and of O. leucogaster, brown. Both species have white ventral fur and distal tail tips

Are grasshopper mice aggressive?

Captive individuals of the same sex are very

aggressive to one another, often fighting to the death

Research uses of grasshopper mice?

Because of their aggression, they are used in behavior studies. These have included studies on predatory behavior (McCarty et al., 1976);

sex differences in behavior, activity, and discrimination

learning (Kemble and Enger, 1984); and drug effects on

aggression (Cole and Wolf, 1970). Grasshopper mice

have also been used to investigate Lyme disease (Borrelia

burgdorferi) transmission via urine (Czub et al., 1992) and

the effect of photoperiod and melatonin on seasonal

gonadal cycles (Frost and Zucker, 1983).

Grasshopper mice have been used to examine comparative

antibody formation (Lochmiller et al., 1991),

cancer induction (Dewsbury and Jansen, 1972; Taylor

et al., 1993), and population dynamics using DNA and

mitochondrial analysis (Alexander and Riddle, 2005;

Riddle et al., 1993; Sullivan et al., 1996).

Grasshopper mice are an alternate host to prairie dogs

(C. ludovicianus) for the plague bacillus Yersinia pestis

Activity, estrus, weaning, and gestation of grasshopper mice?

Females have a 5- to 7-day estrous cycle,

and gestation lasts 26–37 days, nocturnal, weaned at 3 weeks

Do grasshopper mice require dust baths?

yes

The midventral sebaceous gland is larger in the male or female?

Male

What are O. torridus resistant too because of their diet

scorpian venom

Diet of grasshopper mice?

but the main diet consists of grasshoppers,

beetles, and small vertebrates, including other rodents.

What species can you cross-foster grasshopper mice with?

Southern grasshopper mice can be

successfully cross-species fostered on white-footed mice

(Peromyscus leucopus

Are grasshopper mice more sensitive or resistant to the plague?

One of the O. leucogaster populations was associated with a known epizootic focus of the disease and was nearly 2000 times more resistant to mortality than were members of another population from an area historically free of plague

What idiopathic condition are grasshopper mice prone to, similar to the mongolian gerbil?

idiopathic seizures