GI disease in avian and exotic species Flashcards
1
Q
Reptile CE, cf dog
A
- thin abdominal muscles so you can palate organs easily, transillumination sometimes possible (geckos)
- head and mouth examination very important
- faecal analysis is routine
- look for MBD
2
Q
Bird CE, cf dog
A
- observe the bird 1st before handling
- careful handling, don’t restrict rib cage
- look at droppings in travel cage
- limited coelomic palpation due to large ribcage
3
Q
General clinical signs (same as other animals)
A
- reduced appetite/anorexia/dysphagia
- reduced faecal droppings / constipation
- diarrhoea/tenesmus/undigested faeces
- pain (e.g. changed posture)
- lethargy/depression
- weight loss
- dehydration
- haematochezia
4
Q
General clinical signs (different to other animals)
A
- enlarged crop (birds)
- fluffed up (birds)
- heat seeking (reptiles)
- stomatitis (reptiles)
- prolapses (reptiles)
- body swelling (snakes)
5
Q
Vomiting/regurgitation
A
- vomiting only common in ferrets
- vomiting and regurgitation aren’t a clinical sign seen in omnivorous rodents
- regurgitation in reptiles is often husbandry related
- regurgitation is very common in birds – it can be normal or indication of dz
6
Q
Normal regurgitation in birds
A
- courtship behaviour (male psittacines)
- physiological cast formation (raptors)
- crop milk feeding (pigeons)
- fear, excitement (vultures, penguins)
7
Q
Common GIT conditions in reptiles
A
- husbandry causes
- bacterial e.g. mycoplasma
- viral e.g. herpes, inclusion body disease, adenovirus
- endoparasites e.g. oxyurids, ascarids and strongyles
- protozoa e.g. cryptosporidium, coccidia, trichomonas
- neoplasia
- impactions/obstruction e.g. dehydration, FB
- prolapses
8
Q
Reptile husbandry causes
A
- inappropriate temperature (usually too cold / incorrect bulb type)
- dehydration
- inappropriate or excessive quantities of food
- excessive handling after a meal (snakes)
- ingestion of substrate and foreign material
- overcrowding/mixing of species
- poor hygiene
9
Q
What do oxyurids commonly cause?
A
- straining
- eventual cloacal prolapse
10
Q
Body distension/swellings in snakes can indicate
A
- a recent meal
- gravity
- neoplasia
- abscess
- organomegaly
11
Q
Cryptosporidium
A
- protozoa affecting the stomach and SI
- when the stomach is infected it causes V+, weight loss, hypertrophic gastritis
- when the SI is affected it causes D+, passing undigested food and weight loss
- very infectious and progressive in snakes & lizards, and is difficult to treat
- no effective tx
12
Q
Herpes virus
A
- virus often involves multiple body systems (GI + resp signs)
- clinical signs include necrotising stomatitis and enteritis
13
Q
Inclusion body disease
A
- arenavirus affecting snakes
- spread by ectoparasites (mites)
- boas = regurgitation, slow wasting and neurological signs
- pythons = more rapid and acute death
- don’t keep boas and pythons in the same collections because of this virus
14
Q
Adenovirus
A
- affects bearded dragons (usually juveniles)
- causes anorexia, diarrhoea, wasting and neurological signs
15
Q
Foreign bodies
A
- commonly substrate impactions e.g. sand, corncob, wood chip
- water gels designed for feeder insects
- tortoises seem to deliberately ingest white objects
16
Q
Liver disease
A
- hepatitis due to toxins, fibrosis, neoplasia as well as viral, bacterial, fungal or protozoal infections
- mild hepatic lipidosis can be considered normal (depending on age, species, sex, season of year) (don’t over-diagnose if mild, but severe is an issue)
17
Q
What does pathological hepatic lipidosis often occur secondary to?
A
- poor husbandry and diet
- improper or lack of hibernation
- bacterial infection
- parasitism
- NSHP
- POOS
18
Q
Common GIT conditions in birds
A
- crop impactions and infections e.g. sour crop
- FB/lower GI obstruction
- systemic infection (e.g. viral)
- endoparasites (esp backyard chickens)
- dietary change (D+) or poor diet (e.g. hypovitaminosis A)
- GIT infections/enteritis (e.g. bacterial, viral)
- liver dz (e.g. hepatic lipidosis)
- neoplasia
- antibiotic overuse
19
Q
Cause of abnormal regurgitation in birds
A
- iatrogenic (medically induced)
- organomegaly (puts pressure on the GIT and so can force food upwards)
- infectious cause (e.g. bacterial, viral, parasitic, fungal)
- obstructive GIT
- crop stasis +/- infection
- plants (yew, rhododendron, range of houseplants, avocado)
- toxicity (e.g. lead, zinc, chocolate)
20
Q
Crop stasis presents as
A
- crop stasis and dilatation = clinical sign, not dz itself
- regurgitation
- delayed crop emptying
- sour odour (due to stagnant fluid)
- inappetence, dehydration, lethargy
21
Q
Sour crop
A
- can be a primary crop infection
- most commonly crop stasis complicated by secondary bacterial and/or fungal infection
22
Q
Normal crop fill
A
- overnight: no eating
- early morning: empty crop
- daytime: eating
- late afternoon: full crop
23
Q
D+ in birds
A
- watery droppings are normal for some bird spp e.g. nectar feeders (e.g. lorries) and waterfowl
- the consistency of the faecal component of the droppings is affected by the diet
- dietary change may induce (temporary) D+
- confirm that is is D+ and not polyuria
- more often a systemic cause rather than bacterial gastroenteritis
24
Q
Haematochezia causes
A
- causes can be from the cloaca itself or the GIT, uro tract or repro tract
- egg-laying problems
- cloacal papillomas or neoplasia or ulcers
- infectious enteritis
- heavy metal toxicity (kidneys)
25
Q
Cloacal prolapses
A
- same principles for finding the cause of prolapse
- cloacal prolapses are fairly common
- rectal prolapse = due to enteritis, parasites etc
- oviductal prolapse = in egg-laying females that strain excessively
26
Q
Stomatitis (definition, differentials) in birds
A
= inflammation or irritation of the mm in the mouth
- candida (yeast)
- bacterial
- capillariasis (endoparasite)
- trichomoniasis (flagellated protozoa)
- viral e.g. pox virus (wet form), pigeon herpesvirus
(- pox virus uncommon but possible in outdoor birds)
27
Q
Proventricular dilatation dz (PDD)
A
- caused by a Bornavirus that mainly affects psittacine birds
- doesn’t always cause clinical signs, birds can be carriers
- inflammatory dz of the GI and neurological systems
- the damaged nervous system doesn’t allow nutrients to be digested or absorbed
- causes an increase in the size of the proventriculus
- progressive, fatal condition
- no known tx
(- proventriculus = glandular part of the stomach just before the ventriculus [the mechanical part])
28
Q
Liver dz in birds
A
- generally non-specific clinical signs
- biliverdinuria is a strong indication of liver dz (green colouration of urate fractions of the excreta)
- occasionally an enlarged liver can be palpated below the sternum
- PD and V+ are sometimes associated with liver dz
29
Q
Common causes of liver dz in birds
A
- bacteria (mycobacterium, chlamydiosis, salmonella)
- viruses (polyomavirus, adenovirus)
- protozoa (atoxaplasmosis, coccidia)
- parasites (fluke, migrating nematodes)
- toxins (mycotoxins, plants, chemicals)
- hepatic lipidosis is very common in obese birds (high fat diet)
- amyloidosis (due to long term inflammation)
- neoplasia
30
Q
Diagnostic plan
A
- location -> upper or lower GI? other organs involved?
- infectious?
- severity/prognosis?
- diagnosis?
31
Q
Diagnostic options
A
- haematology/biochem
- imaging (radiography, CT, endoscopy, US)
- crop and faecal cytology and bacteriology (C&ST)
- PCR testing
- histology and FNAs
- ex-lap/coeliotomy
- PM for flock/collection problems
32
Q
Radiography
A
- can see FB, organ enlargement, tumours
- contrast medium is very useful in birds and reptiles, can help identify obstructions and slow GI motility
33
Q
Haematology/biochem
A
- can be used to detect some things e.g. inflammatory process/infection, organ damage (liver/kidney)
- can be normal despite pathology of the GIT
- can help determine severity and help stabilise e.g. dehydration
- can detect what organs/systems are involved
- pre-GA for imaging?
- always do a fresh blood smear
34
Q
Faecal testing
A
- flotation parasitology to look for endoparasites
- gram stains +/- culture to look for bacterial causes (commensal?)
- faecal PCR for specific pathogens such as bornavirus (PDD), chlamoydophila (Psittacosis, 3d pooled), crypto
35
Q
Mouth and crop testing
A
- cytology/wet prep of oral lesions or crop fluid
- trichomonas = motile flagellated organism (high power magnification), warming samples increases activity
- candida = yeasts (low levels are normal)
36
Q
Diagnostics for liver dz
A
- faecal examination (in birds might be green)
- total body radiograph: enlarged liver? (trans-illuminaton in geckos)
- haematology exam: PCV, WBC and differentiation, Buffy coat for parasites
- biochemistry: total protein and albumin: globulin ratio
– birds: GLDH, bile acids (AST, LDH)
– reptiles: none, LDH/ALT/ALP/GGT all widely distributed
– rabbits: GGT more specific than ALT and ALP
37
Q
Husbandry tx
A
- correct deficiencies in husbandry and diet
- temp
- UV
- ventilation
- humidity
- diet
- supplements
- good biosecurity (e.g. F10)
- won’t immediately change dz but will increase over time and help with recovery
38
Q
Supportive care
A
- analgesia (e.g. NSAID [meloxicam] and opioids)
- fluids (oral, SC, IC, IV, IO)
- warmth for all spp (specific POTZ for reptiles)
- tube feeding birds and reptiles (high protein recovery diet)
- liver supplements (lactulose, thyroxin, SAM-e, sylmarin, L-carnitine)
39
Q
Opioids in reptiles, birds, small mammals
A
- reptiles: morphine (buprenorphine?)
- birds: butorphanol
- small mammals: buprenorphine
- birds have more kappa than mu receptors therefore butorphanol a better opioid for analgesia
- morphine is best for reptiles but is not often stocked in practice, so buprenorphine is the next best thing
40
Q
Drugs to tx specific underlying causes
A
- injectable vitamins e.g. vitamin B/C appetite stimulant in reptiles
- antibiotics e.g. TMPS, doxy (e.g. Chlamydophila), metronidazole, C&ST recommended
- antifungals e.g. oral nystatin for sour crop, oral amphotericin B for avian gastric yeast, for prevention use apple cider vinegar in drinking water (5-20ml/L)
- anthelmintics e.g. fenbendazole, ivermectin
- antiprotozoal e.g. metronidazole (also an appetite stimulant in reptiles)
- pro-kinetics e.g. metoclopramide (e.g. crop stasis)
- H2 antagonists e.g. ranitidine or famotidine (ferret stomach ulcers)
41
Q
Drug cautions
A
- ivermectin will kill Chelonia, safe for other spp when used appropriately
- Metronidazole is used frequently for protozoal and bacteria infections in snakes, but kingsnakes and indigo snakes appear very sensitive to it (use lower doses if no alternatives)
42
Q
No tx recommended for
A
- salmonella in reptiles (commensal)
- cryptosporidium in reptiles (no effective tx, PTS to prevent suffering and spread)
- PDD in birds (no effective tx)
- with chickens there isn’t a licensed tx in a food producing animal (supportive tx only)
43
Q
Species differences with ‘normal’ bacteria
A
- commensal bacteria of the oral cavity and cloaca in reptiles include Salmonella, E.coli, Pseudomonas, Klebsiella, Aeromonas and Citrobacter
- these may also become pathogenic (often due to poor husbandry)
44
Q
Salmonella spp in reptiles
A
- generally considered a harmless commensal of the GIT in reptiles (rarely pathogenic)
- unsuccessful attempts to produce salmonella-free reptiles
- potentially a significant zoonosis – but salmonella spp in reptiles is different to that which causes dz in humans, but can still potentially carry ‘zoonotic’ salmonella
- don’t recommend tx, to prevent resistant strains
- sensible to assume all reptiles are carriers
- appropriate hygiene measures are important
45
Q
Surgery to tx specific underlying causes
A
- FB/impaction removal (laxatives and enemas may work in selected cases to avoid surgery)
- persistent or severe prolapses
- surgical biopsies
- endoscopic visualisation e.g. stomach ulcers, growths
46
Q
Nutritional support - starving
A
- don’t starve exotic animals, with the exception or prior to a GA
- birds: only for crop emptying (budgie ~1h, parrot ~3h)
- reptiles: 24-72h but often not necessary (anorexic already)
- very important to provide nutritional support to exotic animals with GI dz
47
Q
Parrot diet changes
A
- long term seed-based diets can cause obesity, liver damage and nutritional deficiencies
- make diet changes very slowly or use crop feeds whilst adapting to the new diet (6m-1y)
- ‘Seed junkies’ need to be converted slowly or will suffer from hepatic lipidosis due to starvation which can kill them
48
Q
Medical prolapse tx in reptiles
A
- if tissue is viable
- analgesia (NSAID + opioid)
- lubricate, sugar + lube can help reduce tissue swelling
- gently replace the prolapse with cotton buds
- correct underlying issue e.g. tx endoparasites
49
Q
Surgical prolapse tx in reptiles
A
- cloacaplexy if medical tx hasn’t worked or if reoccurrence
- hemipenes prolapses can be amputated
50
Q
Crop stasis tx in a parrot
A
- crop flush for cytology/diagnostics
- oral metoclopramide
- anti-inflammatories if indicated
- tx underlying cause(s)
- antibiotics/antifungals if indicated by cytology
- radiographs if chronic, obstructive or no response to tx, or if history makes you suspect FB
51
Q
Crop stasis tx in a pet chicken
A
- restrict grass and free access to water
- empty crop content using a tube and perform cytology/diagnostics
- ingluviotomy if emptying not possible
- anti-inflammatories if indicated
- treat underlying cause(s)
- antibiotics if indicated by cytology
- apple cider vinegar in drinking water if yeasts
52
Q
Indications for an ingluviotomy
A
- crop impaction
- crop FB
- crop tumour
- crop burns/injuries
- access to the rest of the GIT
53
Q
Ingluviotomy method
A
- anaesthetise bird
- intubate to prevent aspiration
- pluck feathers
- iodine scrub (no spirit)
- elevate head
- midline incision into the skin
- midline incision into the crop
- empty crop contents
- close the crop with absorbable monofilament suture and atraumatic needle, use an inverting or appositional pattern
- flush with warm sterile saline
- inject saline into the crop to check for leakage along the suture line
- skin closure using an appositional suture pattern and a monofilament suture material
54
Q
A
