rats

why are pet rats so popular on here??

I've wondered the same thing.

shock value?

double

[Edited on Oct 10, 2005 by waldo]

I want a pet snake so my interest in rats are merely of feeding interest.

they're smart, small, and lovable and perform slapstick type humor

They can be really affectionate if you care for them well, kinda like dogs.

They don't take up much space and their poop doesn't stink. Kinda like fish, but furry.

I'll take a hamster over a rat any day.

I have a snake and he's still a baby so he's eating pinkie mice stil. But it's gonna be awesome when he gets bigger and I get to feed him rats. Rats are ugly and digusting and carry disease. All the goth kids are quite fond of them. I wrote in my journal once about how awesome it's gonna be when Larry starts eating rats and these 2 dumb goth "hardcore" bitches were like "That's uncalled for! How would you feel if I talked about animals eating snakes?!??!" Ummm it's nature. Animals eat other animals. Deal with it and go cut yourself in the closet.

I have two hairless rats. They feel like warm little shammy cloths.

because they don't shit where they're not supposed to, don't take what's not theirs, they don't compare.

i personally dont like them but ppl tell me they are fun to play with and pretty smart...i dont think i will have one though

they eat their babies

The choice of pre-killed vs. live has to be made from the get-go. If you buy a snake, and it's been fed live animals, you need to continue along this path, and vice versa.

/Fucking serpents
//Best friend has a snake
///Pays attention, waiting for an opening

We're all bad people. We just have an implied social contract to keep it in check.

Completely untrue.
I've switched snakes from live food to prekilled MANY times with few problems.

Also, there's the snakes who eat anoles and house geckos and frogs and such- they can be successfully switched to mice as well.

A quick google search shows that there doesn't seem to be any opinion on it, so I'll go with your word, as he is a new snake owner. Most people seem to suggest that feeding them dead animals is the way to go, as they don't fight back.

/The more you know

He eats pre-killed mice They can't bite my baby and if those tiny little 2 day old babies have any diseases they are killed when frozen. Good times good times. I think mice are cute but the babies are ugly. I think all rats are disgusting and ugly. Probably cuz I've seen them in the slums in garbage eating shit. And their tails freak me out.

But yes, that's what boards are for

[Edited on Oct 10, 2005 by CrazyWhiteGirl]

Rats are adorable, beautiful and have better personalities than some people. I would never refer to an animal as "ugly" or "disgusting". not even one I didn't like (if one existed)
And as far as carrying disease- any animal can, rats are one of the cleanest animals.

I love mine like children.

Diseases of the Rat (Rattus norvegicus)

Skin Conditions

Staphylococcus aureus - ulcerative dermatitis over nape of neck, shoulders. Prominent colonies of Staphylococcus on surface. Ulcerative dermatitis probably associated with epidermolytic strains of bacteria, but Koch's postulates not fullfilled.

Trichophyton and Microsporum rare in pet rats, can be common in wild rats

Diagnosis: skin scrapings/KOH of lesions, histology with methenamine silver stain

Disease: subclinical to florid ringworm on neck, back and base of tail. Patchy hair loss, hyperkeratosis,

erythema. Arthrospores investing keratin of hair follicles.

Treat with griseofulvin @ 25 mg/kg PO for 30-60 days.

Comment: zoonotic

Ectoparasites

FLEAS Leptopsylla spp., Nosopsyllus spp. Xenopsylla spp.

LICE Polyplax spinulosa (spined rat louse), Hoplopleura pacifica (tropical rat louse)(Zoonotic!)

MITES Demodex spp. Laelaps echidninus (spiny rat mite), Notoedres muris, Ornithonyssus bacoti (tropical rat mite), Radfordia ensifera

Rat arthropods

Arthropods are rare in rats, except Radfordia fur mites. Fleas can serve as intermediate hosts for

Hymenolepis and transmit other agents such as Rickettsia typhy and Yersinia pestis (plague!!)e. Lice can also serve as vectors of disease, including Hemobartonella (Polyplax) and trypanosomes. Mites are rare, except Radfordia, which can be common in some colonies. Non-pathogenic fur mite. Demodex found in as an incidental finding, Laelaps transmits Hepatozoon, but requires absolutely filthy conditions to survive. Notoedres muris is ear mange mite. Burrows in cornified epithelium, causing pruritis and self-trauma. Extremely rare in rats. Ornithonyssus lives off host and is non-selective in host range, including humans. Can cause anemia, debilitation and death in rats. Treat with ivermectin @ 200mcg/kg, or use light dusting of pyrethrin-based flea powder.

Diseases of the Respiratory System

Respiratory disease is one of the commonest reasons for the presentation of pet rats to the vet. The commonest aetiology is a combination of M. pulmonis, CAR and paramyxovirus (Sendai virus). SDAV is also very common. All respiratory diseases are exacerbated by high environmental NH3 levels. Rats possess retrobulbar Harderian glands which secrete tears rich in porphyrins. These tears are often mistaken for blood-staining and should be differentited from such natural staining.

Cowpox Virus

1. Prevalence: rare

2. Diagnosis: lesions

3. Disease: subclinical. Necrotizing rhinitis.

4. Transmission: unknown

5. Duration: unknown

Rat Coronaviruses (Sialodacryoadenitis virus SDAV)

1. Prevalence: v.common

2. Diagnosis: serology, lesions

3. Disease: cervical edema, nasal/ocular discharge including pinkish staining of tears from porphyrin rich Harderian gland production, photophobia, keratitis, megaloglobus, anestrus, fetal resorption. Virus replicates in upper respiratory mucosa (necrotizing rhinitis, tracheitis, bronchitis), with secondary involvement of salivary, lacrimal and lower respiratory tissues (sialodacryoadenitis and interstitial pneumonia). Sublingual salivary gland usually spared. Lacrimal gland dysfunction results in secondary keratitis sicca, ulcers, uveitis, megaloglobus, etc. Chronic wasting disease in athymic rats due to progressive pneumonia and salivary gland lesions. Olfactory mucosal dysfunction in sucklings may lead to failure to nurse, mortality.

Pneumonia is common in infant rats.

4. Transmission: respiratory

5. Duration: acute (except in athymic rats)

Pneumonia Virus of Mice (PVM)

1. Prevalence: common

2. Diagnosis: serology, lesions

3. Disease: subclinical. Lungs develop perivascular and focal interstitial lymphocytic infiltrates in seropositive (recovered) rats. Lesions persist after virus is cleared. Athymic rats likely to have persistent infections with chronic lung disease, but never reported.

4. Transmission: respiratory

5. Duration: acute

6. Comment: PVM more apt to produce lung lesions in naturally infected rats than mice.



Paramyxovirus (Sendai Virus)

1. Prevalence: common

2. Diagnosis: serology, lesions

3. Disease: In enzootic populations, manifests as subclinical or mild disease in rats of one to two months old (when maternal immunity subsides). In naive populations, severe respiratory disease, poor growth and infant mortality. Chronic wasting syndrome/pneumonitis in rnu/rnu rats.

4. Transmission: respiratory

5. Duration: acute

Bordetella bronchiseptica

1. Prevalence: rare, depending on population

2. Diagnosis: culture

3. Disease: may be associated with respiratory disease, but probably in association with primary pathogen, such as Mycoplasma. Rhinitis, otitis, lower respiratory disease.

4. Transmission: contact

5. Duration: unknown

6. Comment: minor primary significance in rats

Cilia-Associated Respiratory (CAR) Bacillus

1. Prevalence: common

2. Diagnosis: silver stain, lesions, serology developed but not used

3. Disease: subclinical to chronic respiratory disease similar to mycoplasmosis. Organisms on apical

membrane among cilia of respiratory epithelium. Often co-infection with Mycoplasma.

4. Transmission: respiratory, presumed

5. Duration: chronic

6. Comment: does not grow in cell-free medium. Found in multiple species. Experimental infection of SPF rats with CAR bacillus will induce chronic respiratory disease and natural infections manifesting as chronic respiratory disease have CAR bacillus in the absence of Mycoplasma, but natural infections are usually mixed.

Hemophilus spp.

1. Prevalence: rare

2. Diagnosis: culture

3. Disease: mild inflammation of lower respiratory tract. Isolation from nose, trachea, lung and female genital

tract.

4. Transmission: unknown

5. Duration: unknown

6. Comment: unclassified species. Single report, but a high prevalence of infection within the colony.



Klebsiella pneumoniae

1. Prevalence: infection common, disease rare

2. Diagnosis: culture

3. Disease: opportunistic gut microflora, but can be associated with respiratory disease (mild rhinitis) and

abscesses.

4. Transmission: orofecal, contact

5. Duration: unknown, probably chronic microflora

6. Comment: seldom significant

Mycoplasma spp. (chronic respiratory disease, murine respiratory mycoplasmosis)

M. pulmonis

M. arthritidis

M. neurolyticum

M. collis

1. Prevalence: common

2. Diagnosis: serology, culture, lesions. Infected rats may be seronegative for months.

3. Disease: often subclinical. Sneezing and snorting characteristic. M. pulmonis is only significan natural pathogen, causing rhinitis, otitis, laryngitis, tracheitis, bronchiolitis, bronchopneumonia with pronounced bronchiolectasis, bronchiolar lymphoid hyperplasia (strong mitogen) and abscessation. M. pulmonis can also cause perioophoritis, salpingitis and torticollis secondary to otitis media. Chronic respiratory disease often associated with CAR bacillus and exacerbated by ammonia, Sendai virus, SDAV, etc. Other mycoplasmas inhabit respiratory or genital tract without disease. M. arthritidis infection can result in seroconversion to M. pulmonis.

4. Transmission: respiratory, contact

5. Duration: chronic

6. Comment: important rat pathogen



Pasteurella pneumotropica

1. Prevalence: common

2. Diagnosis: culture

3. Disease: opportunistic organism. Associated with respiratory, ear, reproductive, mammary gland,

conjunctival and skin lesions, abortion. Co-pathogen with respiratory pathogens (Sendai virus, mycoplasma)

4. Transmission: orofecal

5. Duration: chronic

6. Comment: inhabits respiratory, intestinal tracts as normal microflora

Streptococcus pneumoniae (Diplococcus, Pneumococcus)

1. Prevalence: low

2. Diagnosis: culture lesions, Gram stain exudate

3. Disease: subclinical carriers common (80%). Rhinitis, fibrinopurulent pleuritis, pericarditis, peritonitis, periorchitis, meningitis, otitis and pneumonia. Abscesses.

4. Transmission: respiratory, contact

5. Duration: chronic carriers/acute disease

6. Comment: pathogenicity varies with serotype. Although mice are susceptible to infection, natural infection and disease is rare. Outbreaks of disease can occur among rats.

Pneumocystis carinii

1. Prevalence: infection frequent, disease rare

2. Diagnosis: lesions, silver stain for cysts

3. Disease: pulmonary disease can be induced in naturally exposed young rats by low protein diet combined with steroids. Difficult to induce in older rats. Spontaneous disease not seen in immunocompetent rats and not reported as a problem in athymic rats.

4. Transmission: unknown

5. Duration: chronic

6. Comment: carriers very common in conventional, "dirty" rats, especially rats from colonies infected with multiple viruses (probably a reflection of overall dirtiness)



Diseases of the GI Tract

Rat Adenovirus

Prevalence: common

Diagnosis: serology, inclusions. Cross-reacts antigenically with MAd-2

Disease: subclinical. Intranuclear inclusions in enterocytes of small intestine found incidentally. Inclusions more common in young rats.

Transmission: orofecal

Duration: unknown

Comment: high prevalence of seroconversion with K87 antigen. Rats not susceptible to MAd-1 or -2, so probably separate, but related viruses. Enteric inclusions found only occasionally, but unknown if this is the only adenovirus of rats. Isolation attempts have failed.

Rat Cytomegalovirus (RCMV)

Prevalence: rare or non-existent in laboratory rats, common in wild rats

Diagnosis: histology. Serology, but seldom used

Disease: cytomegaly, inclusions in acinar and duct epithelium of salivary and lacrimal glands, especially

submandibular gland. Mild nonsuppurative interstitial inflammation. Do not confuse with normal exorbital gland morphology.

Transmission: unknown (salivary?)

Duration: chronic

Infectious Diarrhea of Rats (IDIR) Virus

Prevalence: rare

Diagnosis: lesions. Serology available, but not used.

Disease: suckling rats (less than 12 days of age) develop diarrhea, erythema of anus, runting. Malabsorption with watery digesta. Villus attenuation, necrosis, enterocytic syncytia and intracytoplasmic inclusions, especially distal small intestine.

Transmission: orofecal

Duration: acute

Comment: antigenically distinct rotavirus (separate from typical or type 1 rotaviruses). Pathogenesis similar to EDIM in mice, with age-dependent susceptibility to disease but not infection. Infectious to humans and umans probable source of infection in laboratory rats.

Clostridium piliformis (Tyzzer's disease)

Prevalence: rare

Diagnosis: lesions, silver stains, serology developed but not used

Disease: ileitis with dissemination to liver and heart, especially in post-weaning rats. Adynamic ileus can

occur, resulting in megaloileitis, but not a constant feature. Silver stains reveal characteristic intracellular

bacteria.

Transmission: spores, orofecal. In utero transmission possible in immunosuppressed rats, but not likely to be

significant means of transmission.

Campylobacter spp.

Prevalence: variable

Diagnosis: culture, silver stains of lesions

Disease: there is a single report of intracytoplasmic organisms in apical cytoplasm of hyperplastic/neoplastic enterocytes with colonic adenocarcinoma. Agent not characterized, but morphologically reminiscent of Campylobacter-like organisms in hyperplastic enteritides of a variety of species (rabbit, guinea pig, hamster, ferret, lamb, calf, piglet, etc.). Campylobacter jejuni can also be isolated from rats with soft feces. This is probably common and agent can be cultured.

Transmission: orofecal

Duration: unknown

Salmonella enteritidis

Prevalence: low

Diagnosis: culture (especially mesenteric lymph nodes)

Disease: similar to mouse. Often subclinical. Starry coat, soft to fluid feces. Cecal ulcers can persist.

Transmission: orofecal

Duration: acute to chronic. Approximately 60% of rats remain carriers with intermittent shedding.

Comment: infection in rats is currently more common than in mice. Depopulate.

Spirillum minus - see Streptobacillus moniliformis

Streptococcus spp.

Prevalence: organism(s) frequently isolated, but specific disease(s) rare

Diagnosis: culture, lesions

Disease: high morbitity epizootics with 50% mortality among suckling rats. Runting, distended abdomen and fecal staining of perineum. Large numbers of Gram + cocci on surface of normal appearing villi with minimal inflammation. Enterococcus faecium-durans-2 and Enterococcus hirae identified in 2 outbreaks. Streptococcus spp. also an opportunistic pathogen.

Transmission: orofecal

Duration: unknown

Comment: likely to be encountered, but sporadic outbreaks

Cryptosporidium parvum

Prevalence: unknown

Diagnosis: organisms on brush border of villi

Disease: probably opportunistic or marginally pathogenic. Outbreaks of diarrhea with high mortality among infant rats has been reported. Surviving pups runted. Hyperplastic enteritis, especially jejunum, with organisms toward villus tips.

Transmission: orofecal, cysts

Duration: unknown

Comment: Experimental infection in rats is mild and transient, except in immunosuppressed or athymic rats. May have zoonotic potwential. Also may be source of cryptosporidial infections in snakes, although it may be a specific snake pathogen.

Eimeria spp.

Prevalence: common in wild rats, nonexistent in laboratory rats

Diagnosis: intestinal lesions, oocysts in feces

Disease: hyperplastic enteritis, especially in young rats.

Transmission: orofecal, oocysts

Treat with sulphonamides.

Giardia muris

Prevalence: infrequent

Diagnosis: histology, cysts in feces

Disease: subclinical or diarrhea. Low-grade chronic enteritis with trophozoites aligned along brush border of villi.

Transmission: orofecal

Duration: chronic

Spironucleus muris

Prevalence: high

Diagnosis: microscopy of intestine, wet mounts of small intestinal digesta, cysts in feces

Disease: none or rare in rats. If disease present, probably opportunistic.

Transmission: orofecal, cysts

Duration: chronic

Comment: probably not pathogenic in rats

HELMINTHS

NEMATODES - Aspicularis tetraptera, Syphacia muris, Trichosomoides crassicauda

CESTODES - Cysticercus fasciolaris (Taenia taeniaeformis) , Hymenolepis nana and diminuta.



Aspicularis tetraptera, Syphacia muris (pinworms)

Prevalence: common - Syphacia obvelata and Syphacia muris may be same species.

Diagnosis: ova in feces. Scotch tape test for Syphacia, adults in lumen

Disease: none. Syphacia is only species that deposits ova on anus.

Transmission: orofecal. Ova resistant.

Treat with levamisol or fenbendazole.

Cysticercus fasciolaris (Taenia taeniaeformis)

Prevalence: rare

Diagnosis: cysts in liver

Disease: incidental finding of strobilocerci, usually in liver. Rats respond with fibroplasia. Sarcomas can

develop from reactive zone. Studied as a model for parasite-induced neoplasia.

Transmission: contamination of feed and bedding with cat feces

Duration: chronic

Comment: intermediate state of cat tapeworm.



Hymenolepis nana, diminuta - see mouse

Diseases of Uro-Genital System

Leptospira icterohemorrhagiae

Prevalence: rare in pet rats, common in wild rats (<70% of wild rats excreting at any given time).

Diagnosis: culture

Disease: subclinical

Transmission: urinary, contact, copulation, skin wounds

Duration: chronic

Comment: most common L. icterohemorrhagiae in rats, but other species too. Human infection (Wiels Disease) often associated with rat origin.

Trichosomoides crassicauda (bladder thread worm)

Prevalence: infrequent

Diagnosis: bipolar ova in urine, worms in bladder, ureters and renal pelves

Disease: eggs hatch, penetrate stomach wall, migrate through lungs and other viscera and seek urinary tract epithelium. Migrating larvae incite eosinophilia and granulomata, especially in lungs. Adult females burrow in transitional epithelium, smaller males live in lumen or inside female uterus. Reaction minimal, but dead worms may serve as nidus for calculus formation.

Transmission: urine. Egg masses stick to environmental surfaces, resistant to dessication

Duration: chronic

Comment: drug treatment can be effective - try ivermectin @ 200mcg/kg

Chronic renal Disease is common in older rats. By 12-14 months old, up to 50% of rats will have a proteinuria >20mg/dl (normal <5mg/dl). Glomerulosclerosis develops with an interstitial fibrosis. Clinical signs may include polydipsia, fibrous osteodystrophy, hydrothorax and ascites. Biochemistry findings may show elevated BUN (normal 6-23mg/dl) and creatinine (normal 0.2-0.8 mg/dl).

Mycoplasma pulmonis endometritis and pyometra

Preputial Gland Abcess - usually due to Staphylococcus aureus and/or Pasteurella pneumotropica

Musculoskeletal Disorders

Ringtail - if the humidity is too low (<40%) rats can develop annular constrictions around the tail which can cause a distal necrosis and sloughing. Trauma may also give rise to a degloving of the distal tail. Treatment involves surgical removal of the affected area. Then drawing back the skin to exposed the most distal coccygeal verterae, these are remvoed. The skin is then allowed to spring back to cover the stump and the skin is sealed by tissue glue - no sutures to chew!

Disorders of the Sensory Organs and Nervous System

Encephalitozoon may occasionally act as a cause of CNS signs.

Systemic Diseases

Rat Parvoviruses

Rat Virus

H-1 Virus

Rat Orphan Parvovirus

Prevalence: common (all 3)

Diagnosis: serology, lesions (RV). As with mouse OPV, rat OPV does not share virus structural antigens

with RV, H-1. Rat and mouse OPVs are different viruses.

Disease: RV associated with natural disease. Others subclinical. Most RV infections are subclinical, but

can cause fetal resorption, neonatal cerebellar hypoplasia with ataxia, hepatitis, jaundice, steatorrhea.

Hemorrhagic disease in adults, especially when stressed or immunosuppressed. Hemorrhage in CNS and

peritesticular reported.

Transmission: various routes of excretion, in utero possible but not likely

Duration: acute to chronic (latent?)

Comment: RV and H-1 antigenically cross-reactive, but serologically distinct. OPV not cross-reactive, but shares non-structural antigens. IFA serology, using infected cells therefore most useful seroassay.

Corynebacterium kutscheri (pseudotuberculosis)

Prevalence: variable

Diagnosis: culture of lesions, oral washes, cervical lymph nodes. Lesions with characteristic Gram +

colonies

Disease: rats may carry organisms in oral cavity and cervical lymph nodes without disease. Infected cervical lymph nodes may be slightly enlarged (reactive) without abscessation. Stress, immunosuppression, other unknown factors may precipitate bacteremic dissemination to lungs, kidneys, liver, etc. with formation of abscesses. Active lesions possess prominent colonies of Gram + bacilli at periphery, but eventually scar over and resolve.

Transmission: direct contact

Duration: chronic

Comment: pathogenesis may differ from mice. Different organ distribution. Depopulate.



Erysipelas rusiopathiae

Prevalence: rare

Diagnosis: culture lesions

Disease: a single report from Scandinavia with chronic fibrinopurulent polyarthritis, myocarditis and

endocarditis. Organism isolated from lesions.

Transmission: unknown

Duration: unknown

Metabolic Disorders

Neoplasia

Mammary-fibroadenomas are common in adult female rats. Although considered benign these growths can become very large. The mammary tissue in rats and mice can be found at quite a distance from the standard mammary line so such growths may be found throughout the perineal or scapular region and high up on the flanks. Surgery is indicated.

Diseases of the Haematopoetic System

Rat Leukemia Virus (RLV)

Prevalence: 100%

Diagnosis: not done

Disease: none

Transmission: germ line, endogenous provirus

Duration: chronic, latent

Comment: minimal significance in rat. RLV sequences have been combined with MuLV or other RLVs to form experimental rat sarcoma viruses (Kirsten, Harvey, etc.)

Hemobartonella muris

Prevalence: rare

Diagnosis: organisms on surface of erythrocytes; splenectomy of carriers

Disease: usually subclinical. Transient parasitemia, anemia, splenomegaly/

Transmission: Polyplax spinulosa

Duration: chronic, but recovery in some

Comment: severe anemia, parasitemia within 2 weeks of splenectomy. Steroids do not activate subclinical infection.



Miscellaneous

Hemorrhagic Fever with Renal Syndrome (HFRS) Virus

Prevalence: widespread in wild Norway rats. Rare in laboratory rats.

Diagnosis: serology

Disease: none reported in rats, but not thoroughly evaluated

Transmission: urine, saliva, respiratory

Duration: chronic

Comment: Zoonotic. Synonyms: Korean hemorrhagic fever, muroid virus nephropathy, Hantaan virus

(single virus), Hanta virus. Proteinuria, azotemia, petechiae, hemoconcentration, hypotension, renal failure, etc. in humans. Recovery usual, but several fatal cases recently reported in Southwest associated with Peromyscus mouse reservoir.

Mouse Encephalomyelitis Virus (MEV)

Prevalence: seroconversion rare to moderate

Diagnosis: serology

Disease: none

Transmission: orofecal

Duration: unknown

Comment: MHG virus isolated from rats. Antigenically cross-reactive with MEV of mice. Probably mouse origin.

Streptobacillus moniliformis

Prevalence: common in wild rats, rare in pet rats

Diagnosis: culture

Disease: commensal in rats. Disease minimal or absent. Inhabits oropharynx. Can be transmitted by bite, causing abscesses in rats, septicemia in mice (see mice) and rat-bite fever (Haverill fever) in humans.

Transmission: rat bites, milk, contact

Duration: chronic carriers

Comment: Spirillum minus also a cause of rat-bite fever, but not found in laboratory or pet rats.