Intro to Snakes Flashcards
(34 cards)
1
Q
What coelomic cavities do snakes have
A
- Single pleuroperitoneal cavity
2
Q
What is the dental anatomy of snakes
A
- 6 rows of teeth
- 4 rows on top, 2 on bottom
- Venomous snakes have venom delivering teeth (voluntary control)
- can deliver a dry bite when striking instead of with intent to kill
3
Q
Describe GI system of snakes
A
- Short GI tract
- very distensible stomach
- Venomous glands - in venomous species
- Viperides, elapids: located in temporal region
- Colubrids: Devernoy’s gland
- Forked tonge
- Metabolism when in the process of digesting may increase by 7-10x
4
Q
Describe respiratory system of snakes
A
- Unicameral lungs
- cranial part of lungs - respiratory
- Caudal part - avascular, air-sac like
- Only have a RIGHT lung
- except in pythonidae and biodae
5
Q
Describe cardiovascular system of snakes
A
- 2 atria + 1 ventricle
- ventricle divided into 3 subchambers
- Location: ⅓ - ¼ of the length caudal to the head
- Very mobile
- Hear rate increases after a meal
6
Q
Describe the renal system of snakes
A
- Loopless “reptilian” nephrons
- Do NOT concentrate water
- Post-renal handling of urine
- Male snakes have a “sexual segment” of the kidneys
- enlarges the renal organ during heightened reproductive activity
- Produces a secretion rich in proteins and lipids ⇢ copulatory plug
- Do NOT have a urinary bladder
7
Q
What special senses do snakes have
A
- Fused eyelids - shed during ecdysis
- Jacobson organ (vomeronasal organ)
- Infrared receptors
- No external ears
8
Q
Describe the repro system of snakes
A
- Intracoelomic gonades
- Hemipenes in males
- housed in openings caudal to the cloaca
- used for sexing
- Most lay eggs
- viviparous - boids, viperids
9
Q
How are snakes sexed?
A
- Use well-lubricated, clean metal probe or rubber feeding tube
- insert into lateral portion of cloaca (left or right) directed caudally
- stop once resistance is met
- Male: enters area of inverted hemipenis - reaches 6-8 subcaudal scale lengths
- Females - enters blind ended scent sacs - reaches 2-4 subcaudal scale lengths
10
Q
Where can venipuncture be done on snakes
A
- ventral coccygeal vein
- Cardiac vein
11
Q
What unique cells are on the CBC of a snake
A
- Heterophil
- Azurophil - behaves like a heterophil
12
Q
What imaging can be done on snakes
A
- Radiographs
- dorsoventral
- lateral - horizontal beam
- Ultrasound
- need to get gel and alcohol between scles
- CT-scan
- MRI
13
Q
where are IM injections given in snakes
A
- Epaxial muscles
- insert needle between scales
- draw back and inject as normal
- CRANIAL half of the body
- renal/portal changes
14
Q
How are SQ injections given in snakes
A
- Small subcutaneous space with imited vascularity - absorption of medications and fluids variable
- May need to use multiple locations
- No need to tent skin
- Location - lateral body wall
- insert needle parallel to body wall in between scales
15
Q
What other routes for medication administration exist for snakes
A
- Intracoelomic - not recommended
- Oral
- Intravenous - challenging - jugular
- Intraosseous - not possible
- Cloacal route
16
Q
What non-infectious diseases are common in snakes
A
- Hypovitaminosis D
- Rodent Trauma
- Thermal burns
- Fecal Impaction
- Retained shed
17
Q
What infectious diseses are common in snakes
A
- Respiratory disease
- Bacterial
- Viral
- Fungal
- Parasitic
- Inclusion body disease
- Fungal disease
- Gastric cryptosporidiosis
- Amaebiasis
- Snake mites
- Infectious stomatitis
18
Q
What contributes to respiratory disease in snakes
A
- Problems wiht humidity
- problems with ventilation
- Inappropriate temperature (too low
19
Q
What are the clnical signs of respiratory disease in snakes
A
- Open mouth breathing
- dyspnea, tachypnea
- Extended/elevated head or neck
- Forced exhalation
- swollen or distended neck
- stomatits
- discharge from choana and glottis with bubbles
- increased respiratory sounds
- anorexia
- Lethargy
20
Q
What are the different causes of Respiraotyr disease in snakes
A
- All have similar presentation
- Bacterial:
- Aeromonas, E. coli, Klebsiella, Proteus, Psuedomonas, Slamonella
- Atypical: Chlamydia spp, Mycobacterium spp. Mycoplasma spp
- Anaerobes
- Viral:
- Ferlavirus (paramyxovirus)
- Nidovirus
- Fungal
- Parasitic
- Pentastomes
- lungworms (Rhabdias spp.
21
Q
How is repiratory disease diagnosed in snakes
A
- Clin Path:
- CBC - Leukocytosis (heterophilia + azurophilia)
- Biochemistry
- Imaging
- CT mor sensitive and precise for pulmonary lesions versus radiographs
- Endoscopy - tracheoscopy, pulmonoscopy
- Cytology, culture
- swab
- trach wash
- endocopically
22
Q
Treatment for respiratory disease in snakes
A
- Fluid therapy
- Agressive antimicrobial therapy
- min 4-6wks
- Cefotaxime, ceftazidime, ceftiofur
- Treat underlying conditions
- Nebulization
- Husbanry corrections
23
Q
What is Ferlavirus? transmission? Clin signs? Dx? Tx?
A
- Ophidian paramyxovirus
- Neurologic and respiratory signs
- Transmission: repiratory secretions
- Very pathogenic in viperdae and elapidae
- Clinical signs:
- nasal discharge
- open mouth breathing, labored breathing
- pus in oral cavity
- tremors
- opithotonos
- Dx:
- histopath
- EM
- virus isolation
- PCR and sequencing
- serology with paired titers (hemagglutination inhibition)
- Tx;
- supportive care
- husbandry corrections
- antibiotics for secondary bacterial infections
24
Q
What is Nidovirus?
A
- Recently discovered (Coronoaviridae)
- Causes pneumonia and stomatits in pythons and boas
- Clin signs:
- increased clear mucus in oral cavity
- open mouth breathin
- wheezing
- anorexia
- lethergy
- Dx:
- PCR on trach swab or tissue samples
25
What is Inclusion body disease
* Caused by Arenavirus - Reptarenavirus
* Transmission: breeding, bite wounds, fecal/oral, snake mites
* Neuro Signs
* Head tremors
* Anisocoria
* Muscle spasms with neck arching (stargazing)
* Impaired righting reflex
* decreased muscle tone
* abnormal tongue flicking
* seizures
* Dx:
* PCR on blood or tissue
* Inclusion bodies in the WBC (examin buffy coat smear with HE stain)
* Often develop secondary infections/disease due to immune suppression
* Bacterial (salmonellosis)
* Fungal (aspergillosis)
* Protozoal (amoebiasis)
* Neoplasia of the blood/bone marrow (lymphoma)
* Tx - NONE
26
WHat is Snake fungal disease
* Etiologic agent: *Ophidiomyces ophiodiicola*
* most common in wild/zoo snakes
* Potential to cause population decline of many important snake species
* Can become systemic
* Clinical signs: dermatologic infections
* Localized thickening and crusting of skin
* skin ulceration
* nodules
* abnormal molting
* cloudy eyes
* facial disfiguration (can lead to emaciation and death
* Dx: skin biopsy with culture, PCR and sequencing
* Tx: difficult
* Terbinafine (Nebulization, SC injection)
* Other antifungals
* Toxicities reported with voriconazole
* Challenges with achieving therapeutic plasma concentrations
27
What is Gastric Cryptosproidiosis
* *Cryptosporidium serpentis*
* Type A - snakes
* Type B - lizards
* *C. varanii* - primarily in lizards but has been revocered from snakes with proliferative enteritis
* COntributing factors
* Stress
* Concurrent infection
28
Life cycle of Cryptosporidium
* Asexual and sexual reproduction
* Oocysts release sporozoites (S) ⇢ Invade brush border of gastric epithelial cells ⇢ trophozoites (T) and type I meronts (M1) containing type I merozoites (Mz1)
* Merozoites ⇢ trophozoites ⇢ reinfect host
* Merozoites ⇢ macrogamonts (Ma) or Microgamonts (Mi)
* Mi ⇢ microgametes (g) ⇢ fertilize macrogamonts
* 2 mitotic divisions ⇢ Zygote (S)
* zygote ⇢ thick-walled oocyst ⇢ environment
* Zygote ⇢ thin-walled oocyst ⇢ autoinfection
29
Clinical signs of Gastric cryptosporidiosis
* Some asymptomatic
* clear infection
* carriers
* pre--clinical
* Mid-body swelling
* chronic regurgitation
* weight loss
* anorexia
30
How is Gastric cryptosporidiosis diagnosed
* Fecal testing or cloacal swab
* shedding intermittent
* larger sample better
* Serum antibody testing - interpretation difficult, high false negatives
* Gastric lavage
* best if 3 days after feeding
* Gastric swab - PCR or cytology
* Gastric biopsy - Most sensitive
* Sample analysis:
* easiest - cytology
* Direct smear or wet mount in saline or Wright-Giemsa
* false negatives if asymptomatic are common
* Sheather's sugar solution floatation
* Acid fast staining
* Once ID, need further testing to determine species
* Cryptosporidium IFA
* PCR - most sensitive
31
Treatment for Gastric cryptosporidiosis
* None completely effective
* Paromomycin
* improved C/s and decreased oocyst shedding, but recrudescence common
* Confirm all suspected positives
* isolate, treat, and monitor
* if clinical, euthanasia most humane
32
What is Amaebiasis?
* *Entamoeba invadens*
* Snakes most commonly affected
* Contact with freshwater turtles
* chelonians and crocodilians have commensal relationship
* Risk Factors:
* Mixed collections (snakes, carnivorous lizards, aquatic reptiles)
* Poor quarantine and hygiene
* Transfer of infectious cysts form food items such as insects
* Environmental temperatures play role
* Dx: fecal wet mount
* Tx: metronidazole
33
Clinical signs/Histologic lesions of Amaebiasis
* Clinical Signs:
* anorexia
* dehydration
* regurgitation
* diarrhea
* hematochezia
* weight loss
* sudden death
* seizures
* Histologic lesions:
* necrotic and hemorrhagic enteritits and colitis
* hepatitis with hepatic necrosis and abscessation
* Can cause amoebic encephalitis - seizures, neurologic disease
34
What are snake mites
* *Ophionyssys natricis*
* Very common
* vector for many viruses and bacteria
* Tx:
* ivermectin spray of snake and enclosure
* Pyrethrins/permethrin spray of snake and enclosure
* Clean enclosure and discard all substrate and encloseure furniture
* decrease humidity and increase temperature
* predatory mites
* bravecto
