Ferret Medicine Flashcards
(51 cards)
1
Q
Common reasons for presentation
A
- D+ + V+ - gastroenteritis
- Dental disease
- Fight wounds
- Insulinoma
- Lymphoma
- Adrenal disease
- Cardiac disease
- Persistent oestrous
2
Q
D+ + V+ - GIT physiology
A
- Typical diet = dry ferret diet (35-40% protein)
- Hunting ferrets - fresh carcass feeding
- Short simple GI tract (no caecum)
- Rapid transit time (~ 3
hours)
3
Q
Infectious causes of GI disease - bacterial
A
- Helicobacter mustelae - gastritis
- Campylobacter jejunae
- Lawsonia intracellularis
4
Q
Infectious causes of GI disease - viral
A
- Coronavirus (ECE) (Epizootic Catarrhal Enteritis)
- Canine distemper
- Rotavirus
5
Q
Infectious causes of GI disease - parasitic
A
- Coccidia
- Giardia
- Cryptosporidium
6
Q
Non-infectious causes of GI disease
A
- Inflam - IBD
- Neoplastic - lymphoma
- Traumatic - FB
- Stress/diet change
- Idiopathic - megaoesophagus
7
Q
Coronavirus
A
- Epizootic catarrhal enteritis (ECE) - spread by contact
- Ferret shows, rescue ferrets
- Green slime disease
- Dx: faecal PCR
- Tx - general supportive care - allow to develop immune response
- Beware systemic FIP-like form
8
Q
Helicobacter mustelae
A
- Ulcerative gastritis
- CS - Anorexia, nausea, V+/D+, abdo pain, melaena * Recent stress
- Dx - Gastric biopsy and histopathology
9
Q
Helicobacter mustelae
A
- Amoxicillin 20 mg/kg PO q 12 h
- Metronidazole 20 mg/kg PO q 12 h
- Bismuth subsalicyclate (Pepto-bismol) 0.25 mL/kg PO q 4 - 6 h
10
Q
Arenal disease
A
- Neutered ferrets
- Middle aged
- Aged 3 ½ to 4 ½ years peak time
- Neutered > 18 months previous
- Indoor pets
- light > 8 h/day
- No sex predilection
- Overproduction of sex hormones, most common cause = hyperplasia of adrenal gland(s) (+ tumours seen)
11
Q
Adrenal disease CS
A
- Asymptomatic
- Tail alopecia, comedones
- Progressive bilateral
flank alopecia - easily epilated, may be pruritic (40%)
Sex hormone changes
- Vulval swelling
- Dysuria with prostatomegaly
- Aggression/sexual behaviour
- Increased scent
- Mammary gland enlargement
- Petechiae
12
Q
Adrenal disease Dx
A
- CS + signalment - suggestive but not pathognomonic - older ferret, recently neutered
- Exclusion of other causes - parasitic skin disease, ovarian remnant
- Further diagnostics needed to confirm adrenal cause
- Hormone panel
- US
13
Q
Adrenal disease hormone panel Dx
A
Measurement of multiple
sex hormones
- Oestradiol
- 17-hydroxyprogesterone
- Androstenedione
- Dehydroepiandrosterone sulfate
- False negatives possible as only the three most common hormones are included in most panels
14
Q
Adrenal disease US Dx
A
Right adrenal gland
- Identify vena cava at the level of the right kidney
- Adrenal gland adjacent to vena cava, where portal vein joins
- Should be less than 10 mm long and 4 mm wide
Left adrenal gland
- Identify renal artery at level of cranial left kidney
- Adrenal gland between aorta and renal artery
- Should be less than 10.5 mm long and 4 mm wide
Common abnormalities
- Increased size
- Rounded appearance
- Altered echogenicity
15
Q
A
- Normal left adrenal gland
- Elipsoid
- Within expected size parameters
16
Q
A
- Left adrenal hyperplasia
- Rounded
- Excessively wide (6.1 mm)
17
Q
A
- Right adrenal adenocarcinoma
- Enlarged (8.4 mm
- Impinging on vena cava
- Irregular echogenicity - mottled (not homogenous)
18
Q
Adrenal enlargement
A
- Adrenal hyperplasia (56%)
- Adenocarcinoma (26%)
- Adrenocortical adenoma (16%)
- Cystic/other change (2%)
- All presumed to be related + progressive changes
19
Q
Adrenal disease medical therapy
A
- Mitotane/Trilostane - no effect on sex hormone production, dec cortisol, cushing;s Tx in dogs
- Melatonin implant - cosmetic effects
- Androgen/oestrogen blockers - can be used short-term to reverse severe clinical signs - get to urinate
- GnRH agonist - Desloerlin acetate implant - lasts > 18 m, expensive, easy to obtain
20
Q
GnRH agonist MoA
A
- Pulsatile release of GnRH is overcome
- Constant high level of GnRH - > negative feedback
- Lack of release of FSH + LH - > shutdown of adrenal stimulation
- Ineffective if autonomous tumour has developed - tumour -> adrenalectomy
- Effective if hyperplasia, before neoplasia
21
Q
Adrenal disease prevention
A
- Data indicates surgical neutering main factor
- Removal of gonads prevents negative feedback on
hypothalamic-pituitary axis - LH and FSH levels high
- Adrenal receptors present
- Adrenal hyperstimulation and exogenous sex hormone
production results
22
Q
Reasons for neutering - even though risk of adrenal disease
A
- Breeding control
- Reduce aggression
- Minimise ‘unpleasant’ scent
- Prevent reproductive neoplasia/infections
- Prevent oestrogen toxicity in unmated jills
- Adrenal disease not seen widely in UK, risk of oestrogen marrow suppression bigger risk - when remain in season + not mated (induced ovulators)
23
Q
Options for neutering/contraception
A
- Sx neuter
- Deslorelin implant
- Both neuter + deslorelin implant
- Vasectomised hob
- ‘Jill jab’
24
Q
Sx neuter
A
- Introduces risk of adrenal disease
- Likely that some degree of hormonal alteration will occur
- Not all neutered ferrets will develop clinical disease
- Outdoor ferrets low-risk
- Cost effective
- Permanent and reliable method of preventing
pregnancy and marrow suppression - Can use deslorelin should adrenal disease develop
25
Chemical neuter - Deslorelin implant
- Appears safe and effective
- Not permanent
- 4.7 mg: recommended to replace every 12 - 18 m
- 9.4 mg: lasts 3 - 4 years
- Expensive
- NB used off licence in most cases
- 9.4 mg licensed for chemical
castration of male ferrets
26
Both neuter + deslorelin implant
- Spay prevents breeding and marrow suppression
permanently
- Deslorelin acts as concurrent preventative treatment for
negative adrenal aspect of spay
- Expensive combination for many owners
- Need to replace implant in future
27
Vasectomised hob
- Sterile mating brings entire females out of season by mating w/ them, won't produce viable ejaculate
- Only one animal requires surgery
- No need for medical intervention in any animal
- Utilises physiological contraceptive
- Hob can inflict bite injuries on females
- False pregnancies common
28
'Jill jab'
- Injected when signs of oestrus seen, requires vigilance by owner
- Variable costs - repeated consults, single use vials raise costs
- Potential for pyometra (rare)
rare
- Delvosteron (0.5 mL) - licensed - not currently available
- HCG (100 iu) – off licence, risk of reduced efficacy or anaphylaxis with repeat injection - okay as one-off, efficacy can reduce as Ab develop against hormone
29
Decision on neuter/contraception protocol
- Rescue centre = Sx neuter
- Working ferrets = vasectomised hob
- Per ferrets = any options
30
Insulinoma
- Pancreatic islet B-cell neoplasm
- Overproduction of insulin - drives glucose into intravascular space
- Hypoglycaemia
- Episodic lethargy and ataxia
- Approx 25% of ferret neoplasms - genetic cause, excessive CHO exposure, common in middle-aged ferrets = approx 4 y/o
31
Insulinoma Dx
- Blood glucose < 3.4 mmol/L highly indicative if not starved
- If not convincing then fast for 3 - 4 h + retest
- Ensure ongoing observation
- Measurement of insulin ideal
- Normal/high insulin in face of hypoglycaemia indicative
- ALT and AST may be elevated due to hepatic lipidosis
- US = limited use: microadenomas, can use to assess for metastasis (liver, lymph nodes)
32
Insulinoma - first aid Tx
- Offering food often sufficient
- Syrup on mucosa for inappetant patients
- IV glucose in comatose patients = 50% dextrose (0.25 - 2 mL) as slow bolus + maintain on glucose saline
- Fluid therapy
- Ad lib food high protein, low carbohydrate food access
- SC glucose = one-ff - don't used repeatedly - will get irritation
33
Insulinoma - long-term care Tx
- Partial pancreatectomy - methylene blue IV for visualisation, not used clinically
- Px - Histopathology indicated as adenomas,
carcinomas and hyperplasia have different prognoses
- Diet management
- Diazoxide
- Prednisolone
- Octreotide
- Monitor BG - initially q 3 - 4 d -> stable, q 2 m, point measurement before medication admin, O can do at home
- Survival 12 - 24 m - low rate of metastasis, progressively refractive to medical management
34
Insulinoma Tx - partial pancreatectomy
- Methylene blue IV - enhances visually, not used clinically
- Histopath - indicated as adenomas, carcinomas + hyperplasia - diff Px
35
Insulinoma Tx - diet managment
- Low CHO, high meat diet
- Ad lib access to food
36
Insulinoma Tx - Diazoxide (Eudemine)
- 5 - 15 mg/kg BID
- Inhibits insulin secretion
- Promotes gluconeogenesis + glycolysis
- Inhibits glucose uptake
37
Insulinoma Tx - Prednisolone
- 0.25 - 2 mg/kg BID
- Inc hepatic gluconeogenesis
- Dec peripheral tissue glucose uptake
- Inhibits insulin binding to receptors
- Control symptoms while disease progresses
- Either 1y or rescue therapy
38
Insulinoma Tx - Octreotide
- Somatostatin analogue
- Used for refractory cases in other species - limited benefits in ferrets
39
Lymphoma
Two distinct subtypes
- Juvenile lymphoma
- Adult onset lymphoma
- Transmissible + seen as ‘outbreaks’
- Viral aetiology?
- Transplantable neoplastic cells? - through bites
- Predominantly T cell lymphoma
40
Juvenile lymphoma
- Aged < 3 y, typically 1 y
- Lymphoblastic
- Organomegaly due to diffuse infiltration
- Thymus enlargement common
- Poorly responsive to treatment
41
Adult onset lymphoma
- More common
- Aged > 3 y
- Lymphocytic
- Peripheral + abdominal LN enlargement
- Clinically ‘well’ initially
- Eventual infiltration into viscera -> progressive non-specific signs -> splenomegaly common in ‘normal’ and neoplastic cases
42
Lymphoma Dx
- FNA of organ/lymph node
- Incisional biopsy of viscera
- Excisional biopsy of lymph node - avoid mesenteric nodes due to interference with vasculature
- Cytology of fluid
43
Lymphoma Tx options
- Prednisolone - sole therapy
- Cyclophosphamide + vincristine = poorly tolerated, cause Tx-limiting neutropaenia
- TUFTS oral + SC multidrug protocol
- Mean survival = 6 m (0.5 - 19 m) - T cell = 5 m, B cell = 8.4 m
- On chemo survival: T cell = 4.3 m; B cell = 8.8 m
44
Lymphoma - sole prednisolone therapy
- Often gives remission for weeks to months
- Resurgent (relapse) lymphoma is resistant to further chemotherapy
- Rapid deterioration following recurrence
- Cheap, simple and non invasive
45
Lymphoma - TUFTS protocol
- Oral and SC multidrug protocol: Prednisolone; L-asparaginase; Cyclophosphamide; Cytarabine; Methotrexate; Chlorambucil; Procarbazine
- 26 week treatment period with 19 visits
- 7 haematology samples
46
Co-morbidity of adrenal disease, insulinoma + lymphoma
- AKA = Multiple Endocrine Neoplastic Syndrome
- Chronic inflammatory process?
- Viral aetiology
- Coincidence - ferrets living longer lives; common diseases of elderly animals; chronic conditions only detected on presentation
47
Routine vaccination
- Distemper = only routine given in UK
- Full vs 1/2 or 1/4 / yearly, two yearly or 6 yearly boosters
- Give 1 full vial at > 12 w/o
- Booster q 2 y
- High risk animals - initial dose 8 w/o + 2nd 12 w/o, e.g. Rescues, kept outdoors, risk of fox contact
48
Elective vaccs
- Feline parvovirus (feline panleucopoenia) - requested vacc, but ferret virus different
- Parvovirus in ferrets (Aleutian disease) is caused by a mink parvovirus
- No vaccine for aleutian disease in the UK
- No clinical evidence that vaccination with feline parvovirus is protective
- Not currently advisable
49
Parasite control - fleas
- Cat flea (Ctenocephalides felis)
- Routine control not commonly used unless persistent problems exist
- Frontline Combo + Advocate both licensed for use in ferrets
50
Parasite control - ticks
- More of a problem in working ferrets
- Frontline combo licensed
51
Parasite control - endoparasites
- Not Tx routinely
- No licensed drugs
- Fenbendazole (cestodes, nematodes, mesocestoides sp.) - either 20 mg/kg PO q 24 h for 5 d or 50 mg/kg PO q 24 h for 30 d
- Piperazine (intestinal nematodes) - 50 - 100 mg/kg PO q 14 d
- Praziquantel (cestodes) - 5 - 10 mg/kg PO, SC repeat in 10 - 14 d
