Endocrine diseases in small mammals and exotics Flashcards
What clinical signs are associated with endocrine diseases in small mammals? (non-specific and system specific)
- Non-specific clinical signs of endocrine disease include PU/PD, anorexia, lethargy/weakness, weight loss.
- More specific signs depend on systems effected:
- Pancreatic adenomas: hindlimb weakness, nausea, gazed expression, ataxia, collapse, coma.
- Hypercalcemia: dysuria, pollakiuria, haematuria, thick, beige-brown urine, urine staining, abdominal pain.
- Reproductive: swollen vuvla, symmetrical hair loss, palpable cystic ovaries, anaemia etc.
What clinical signs are associated with metabolic bone disease in reptiles? How is it diagnosed? How is it treated?
- Anorexia
- Lethargy/weakness
- Abnormal gait
- Bone deformities and swellings e.g. mandible, long bones.
- Pathologic fractures
- Constipation, egg binding, cloacal prolapse
- Dysecdysis
- Muscle tremors/fasciculations and tetany.
Diagnosis
- total and ionised calcium may be low or normal
- History (diet, UV-B provision, egg-laying, temperatures etc).
* Total and ionised calcium, albumin, ALKP.
* Whole body radiographs (2 views).
Treatment
- Medical treatment
* Give calcium, route depends on severity: oral (calcium glubionate) or injectable (e.g. calcium gluconate IM or slow IV CAUTION)
* Cage rest and analgesia
* Apply splints to any recent/unstable fractures.
* Euthanasia if severe
- Surgical treatment
- Treating fractures surgically usually contraindicated.
- If a reptile, consider an ovariectomy once stable?
- Husbandry changes
- Provide warmth and the appropriate UV-B light (reptiles and birds)
- Reduce reproductive drive:
- Shorten day length
- Remove nest sites and/or mate (owner?)
- Diet changes
- Convert to an appropriate diet for the species.
- Use Ca/Vit-D supplement (appropriately).
What clinical signs are associated with endocrine diseases in birds? (non-specific and system specific)
- Non-specific clinical signs of endocrine disease include PU/PD, anorexia, lethargy/weakness.
- More specific signs depend on systems effected:
- Dyspnoea, regurgitation and dysphagia are seen with thyroid goitres in hyperthyroidism.
- Weakness, ataxia, bone deformity/fractures, tetany and seizures are common in parathyroid disease (MBD).
What are common endocrine diseases in the ferret, guinea pig, rabbit and other rodents?
Ferret
* Hyperadrenocorticism
* Insulinoma
* Persistent Oestrus
* Diabetes mellitus
* Hypothyroidism
* Phaeochromocytoma
Guinea pig
* Cystic Ovaries
* Urolithiasis (hypercalcaemia)
* Alopecia (during pregnancy/lactation)
* Diabetes mellitus
* Hyperthyroidism
* Hyperadrenocorticism
Rabbit
- Bladder sludge (hypercalcaemia)
- Urolithiasis (hypercalcaemia)
* Hypocalcaemia
* Diabetes mellitus
* Adrenal gland tumours
Other rodents
* Diabetes mellitus e.g. hamsters, degus, chinchillas, gerbils.
* Hyperadrenocorticism e.g. hamsters, gerbils.
* Pituitary Gland Adenoma e.g. rats
What causes insulinomas in ferrets? How do you treat clinical signs? How would you diagnose it? How is it treated?
- Pancreatic adenomas in ferrets.
- Hyperinsulinaemia leading to hypoglycaemia
- Clinical signs stop in response to food or glucose!
- Average occurrence 2-8 years.
- Feeding processed dry foods high in carbohydrate might stimulate the development of tumours.
Diagnosis
* Blood glucose <3.4 mmol/L after 4 hour fast.
* Clinical signs disappear are eating food (or being given glucose).
Treatment
* Medical: prednisolone +/- drugs that inhibit insulin secretion e.g. diazoxide or a somatostatin analogue.
* Surgery: partial pancreatectomy
* Diet changes:feed a high protein and fat, low in carbohydrate diet. Feed small but frequent meals.
What are common causes of hypercalcaemia in rabbits? What clinical signs will it cause?
Common causes
* Increased dietary intake e.g. alfalfa hay
* Renal disease
* Primary hyperparathyroidism
* Hypervitaminosis D
* Osteomyelitis
* Paraneoplastic syndrome e.g. thymoma
Consequences
- bladder sludge
- urolithiasis
- In rabbits persistently raised calcium may result in:
- Dystrophic calcification, particularly in the aorta and kidneys e.g. kidney damage.
- Hypermineralisation of the skeleton.
What are other causes of bladder sludge? How is it treated?
- Dehydration
- Reduced movement e.g. arthritis, obesity, and confinement.
- Not fully voiding bladder when urinating e.g. partial obstruction, spondylosis, abdominal pain.
Treatment
- Medical treatment
- Identify and treat any conditions that will predispose to urinary disease e.g. joint pain or abdominal pain.
* Fluid therapy to increase the need for urination.
* Gentle badder expressions to full void bladder.
* Place a urinary catheter and flush the bladder if unable to remove sludge through manual bladder expressions.
* If blood in urine, possible secondary infection that needs treating.
- Surgical treatment
* Cystotomy: same surgery as cats and dogs, extra precautions for the anaesthesia and minimise gut handling.
* Sample urine directly from the bladder for culture and sensitivity.
* Catheterise and flush so calculi in the urethra are flushed back into the bladder.
- Husbandry changes
* Change diet e.g VetCare Plus urinary diet, reduce vegetables that are high in calcium, no alfalfa hay.
* Weight loss if overweight.
* Increase water intake.
* Encourage exercise.
* Reduce stress.
What are the consequences of hypocalcaemia in rabbits?
- Calcium deficient diet leads to reduced serum calcium and increased PTH secretion.
- Leads to demineralisation of the skull, teeth and skeleton.
- Spine fractures and dental disease are commonly found.
- PTH also increases RBC osmotic fragility causing anaemia.
- Hypocalcaemia may be seen before parturition.
What are common endocrine disorders in reptiles?
- Hypocalcaemia/Metabolic bone disease:
- Nutritional secondary hyperparathyroidism (NSHP)
- Renal secondary hyperparathyroidism (RSHP)
- Hypercalcaemia
- Hypothyroidism and hyperthyroidism
What causes nutritional secondary hyperparathyroidism in reptiles?
- ↓ calcium in the diet (or ↑ phosphorous)
- Lack of UV-B light
- Poor environmental temperatures.
- ↓ Vitamin D in the diet
What causes renal secondary hyperparathyroidism?
Common causes of kidney disease:
* Over-supplementation of vitamin D3
* Malnutrition e.g. hypovitaminosis A
* High protein diet
* Kidney infections
* Chronic dehydration
What causes hypercalcaemia in reptiles and birds? What are the consequences of prolonged hypercalcaemia?
- Most commonly physiological in reproducing females.
- Para-neoplastic hypercalcaemia not reported.
- Can be caused by hypervitaminosis D and excessive dietary calcium intake in both reptiles and birds.
- In reptiles particularly, it can also be caused by primary hyperparathyroidism and osteolytic bone lesions.
Consequences of prolonged hypercalcaemia:
* Soft tissue mineralisation
* Nephrocalcinosis -> visceral and articular gout
What are common endocrine diseases in birds?
- Medullary hyperostosis
- Hypocalcaemia (NSHP and RSHP)
- Hypercalcaemia
- Thyroid hyperplasia (goiter) due to dietary iodine deficiency.
What is medullary hyperostosis?
- Hyperostosis = calcium storage in medullary bone changes the pneumatic appearance to solid and dense mineral.
- Egg laying places huge demands on calcium supply.
- Begins at 6 weeks prior to egg laying.
- Hyperostosis is reported in bothnormaland abnormal female psittacinebirds.
- Under the influence of oestrogen and vitamin D.
- Where calcium/Vitamin D3 is insufficient, a moth-eaten appearance often occurs.
What clinical signs are associated with hypocalcaemia in birds? How is it diagnosed? How is it treated?
Hypocalcaemia in birds has the same clinical signs as reptiles, plus feather plucking due to bone and joint pain. Breeding females also show egg-binding, soft-shelled eggs and infertility.
Diagnosis
- total and ionised calcium may be low or normal
- History (diet, UV-B provision, egg-laying, temperatures etc).
* Total and ionised calcium, albumin, ALKP.
* Whole body radiographs (2 views).
Treatment
- Medical treatment
* Give calcium, route depends on severity: oral (calcium glubionate) or injectable (e.g. calcium gluconate IM or slow IV CAUTION)
* Cage rest and analgesia
* Apply splints to any recent/unstable fractures.
* Diazepam +/- anaesthesia if seizure (birds).
* Deslorelin implant in birds if a prolific egg-layer?
* Euthanasia if severe
- Surgical treatment
- Treating fractures surgically usually contraindicated.
- Husbandry changes
- Provide warmth and the appropriate UV-B light (reptiles and birds)
- Reduce reproductive drive:
- Shorten day length
- Remove nest sites and/or mate (owner?)
- Diet changes
- Convert to an appropriate diet for the species. Do this very slowly in parrots (over 6 months).
- Use Ca/Vit-D supplement (appropriately).
