Reproductive disease in avian and exotic species

• Clinical signs of reproductive disease in reptiles

  Lethargy

  Anorexia

  Bloated/ distended celomic cavity.

  Dyspnoea

  Lameness/ leg paresis (tortoises mainly)

  Swelling around the cloaca.

  Straining +/- blood or prolapsed tissue from the cloaca.

  Behaviour changes e.g. pacing, nesting, digging.
• Clinical signs of reproductive disease in Birds

  Lethargy/ depression

  Inappetance/ reduced crop fill

  Bloated/ distended

  Dyspnoea

  Seizure/ tremors

  Separation from the group/ being bullied (chickens).

  Lameness/leg paresis, reluctant to move/perch.

  Straining +/- blood or prolapsed tissue from the cloaca.

  ’Fluffed up’ appearance, hunched posture, wide legged stance.

  Behaviour changes e.g. Feather plucking, aggression, regurgitation.
• Common reproductive conditions in the reptile

  Prolapse e.g. hemipene/cloaca/oviduct

  Impactions e.g. hemipene/femoral pores

  Hypocalcaemia

  Pre-ovulatory ovarian stasis (POOS)

  Post-ovulatory egg stasis (POES/Dystocia)

  Neoplasia
• Common reproductive conditions in the Reptile - prolapse

  Hemipene, cloaca and uterine prolapses are common.

  First step of treatment - identify the prolapsed organ. Common causes are constipation, endoparasites, impaction, egg binding, egg in the bladder, cystitis/bladder stones, traumatic copulation
• Common reproductive conditions in the Reptiles - pre-ovulatory ovarian stasis

  In oviparous reptiles, the ovaries produce follicles, when they ovulate these become eggs.

  Some reptiles, like tortoises, are induced ovulators.

  For this reason, it is very common for tortoises to suffer from POOS.

  Ovaries produce follicles but they never ovulate so they increase in volume and size each year -> space occupying effect -> fatal.
• Common reproductive conditions in the Reptile - obstructive dystocia


  Uroliths

  Egg/foetus oversize.

  Pelvic abnormalities.

  Renomegaly.
• Common reproductive conditions in the reptiles - non-obstructive dystocia

  Hypocalcaemia

  Inadequate husbandry, diet, nesting site.

  Poor muscle tone.

  Dehydration.
• Common reproductive conditions in the Bird

  Sexual frustration.

  Chronic egg laying

  Abnormal eggs

  Egg binding

  Prolapse e.g. oviduct, phallus

  Coelomitis (egg yolk peritonitis).

  Salpingitis (inflammation of the oviduct)

  Neoplasia.
• Sexual frustration in birds

  This is a very common problem for pet parrots who live alone.

  In the wild they have monogamous pairings that bond for life.

  Behaviours that bonded birds display to each other:

  • Stroking
  • Beak touching
  • Preening/ cleaning each other.
  • Feeding each other
• What problems will sexual frustration cause in birds?

  A bird that is lonely or inappropriately bonded to their owner will be more likely to demonstrate:

  • Excessive regurgitation (especially if there are mirrors in their cage).
  • Feather plucking due to frustration, stress and anxiety.
  • Jealousy and aggression, especially to spouses of their partner.
  • Excessive egg laying.
• How to prevent sexual frustration in birds?

  Share interaction and caring responsibilities equally between members of household.

  Avoid stroking down length of back.

  Avoid certain behaviours e.g. mouth to beak feeding.

  Do not positively reinforce courtship behaviours E.g. regurgitation.

  Remove mirrors in their cage so they cannot self-bond.

  Keeping them a a pair (depending on species).
• Chronic egg laying in birds

  Particularly common in captive cockatiels, lovebirds and budgies.

  They can lay a large number of eggs in succession.

  Can be without the presence of a mate and outside of the correct breeding season.

  Removing the eggs as they are laid can ‘induce’ the bird to lay more (‘double clutching’).
• What can chronic egg laying lead to?

  Uterine intertia

  Calcium depletion

  Egg binding

  Yolk coelomitis

  Oestoporosis

  Uterus prolapse/ cloaca
• What are the predisposing factors for avian chronic egg laying?

  Increased photoperiod

  Food type (e.g. high fat)

  Presence of actual or perceived mates.

  Lack of environment enrichment.
• Why is egg binding a problem?

  An egg lodged in the pelvic canal may compress the pelvic blood vessels, kidneys, ureters and ischiatic nerves causing:

  • Circulatory disorders
  • Lameness, paresis or paralysis.
  • Pressure necrosis of the oviductal wall may occur.
  • Dystocia may causes metabolic disturbances by interfering with normal defacation and micturition, and cause ileus and renal disease.
• What are the common causes of egg binding?

  Laying e.g. chronic egg laying or first time layers.

  Eggs e.g. malformed eggs

  Disease e.g. systemic disease, oviductal disease.

  Husbandry e.g. lack of exercise, low temperatures, malnutrition (deficiencies Ca, Vita A and E and obesity).

  Genetic predisposition.
• What can eg binding lead too?

  Circulatory disorders

  Lameness, paresis or paralysis.

  Pressure necrosis of the oviduct.

  Metabolic disturbances by interfering with normal defecation and micturition, and cause ileus and renal disease.
• What is Coelomitis?

  Inflammation of the celomic cavity (mammal equivalent is peritonitis). Celomic cavity because fluid filled.
• What are the common cause of Coelomitis?

  Ectopic eggs

  Ovarian neoplasia

  Cystic ovarian disease

  Oviductal disease e.g. salpingitis.
• Diagnostic test for reproductive issues in the Bird

  Diagnosis can often be made based on clinical exam and history e.g. prolonged straining and nesting with an egg palpable.

  Diagnostic imaging is the most useful when diagnosing reproductive diseases e.g. looking for eggs, follicles, neoplasia.

  Aspiration +/- culture and sensitivity and cytology is useful for diagnosing e.g. egg yolk peritonitis and treating infections.
• Exploratory laparotomy in birds for reproductive issues

  Exploratomy laparotomy sometimes used to both diagnosis and treat if a lesion is found in a radiograph or abdominal palpation. This isn't often performed inn birds due to the risks associated with celomic surgery in birds, bit it is commonly performed in reptiles.
• Blood tests and feacal testing in birds with reproductive issues?

  Blood tests:

  • Biochemistory, can be useful to assess systemic health and rule in or out other differentials and body systems as the underlying causes e.g. MBD and renal disease can present with lameness, lethargy, fluffed up, seizures.

  Faecal testing:

  • Parasitology, can be useful to rule in or out other differentials and underlying causes e.g. cloacal prolapse.
• Blood testing for reproductive issues in birds

  Calcium:

  • When female birds and reptiles are reproductively active they tend to have increased total Ca levels (not ionised).
  • Useful to double check findings that may be incidental e.g. follicles in reptiles.

  Can also have increased uric acid levels, serum proteins (mainly globulins), and cholesterol.
• Radiography for birds with reproductive issues

  Very useful in birds, can give good detail.

  Useful for screening in reptiles, can identify large space occupying lesions but can be hard to identify the organ and structure involved.
• Ultrasound for birds with reproductive issues


  Not very useful in birds due to feather coverage.

  Very useful in reptiles, particularly for space occupying lesions that are hard to indemnify on radiographs e.g. follicles.
• CT for birds with reproductive issues


  Superior for diagnosing reptiles, especially in tortoises, but expensive and will often require referral.
• Pre-ovulatory ovarian stasis diagnosis in birds

  Radiograph = lateral view shows reduced lung field but no eggs.

  Bloods = increased total calcium (causes you to suspect reproductive cause).

  Ultrasound = via prefemoral fossa, can visualise follicles (or CT scan).
• Coelomitis diagnosis in birds

  History of prior egg laying.

  Hugely distended on clinical exam.

  Radiogrpah = fluid filled soft tissue density throughout the celomic cavity. Displacement of ventriculus and compressed air sacs.

  Celomic aspirate showed a large volume of cloudy fluid with evidence of egg yolk.
• What are the surgical treatments for reproductive issues in birds?

  Ovariectomy for pre-ovulatory ovarian stasis (follicles).

  Salpingohysterotomy/ectomy for egg binding, oviductal disease, ovarian tumours, chronic egg laying.

  Ovocentesis for egg binding/post-ovulatory stasis.

  Orchidectomy for tumours.

  Prolapse = lubricate and replace or amputate prolapses, can place stay sutures to prevent future prolapses and treat the underlying cause.
• Medical treatments for reproductive issues in birds

  Hormone implants e.g. Leuprolide acetate (Lupron) or GnRH-agonist (deslorin implant), stops reproduction. Expensive and short duration.

  Hormone injections e,g, repeat oxytocin injections for egg binding/ post-ovulatory stasis +/- prostaglandin.

  Calcium injections if hypocalcaemia (after blood test).

  Ascites: abdominocentesis and treat with NSAIDs if coelomitis. +/- antibiotics (only secondary infection has tracked up from vent).

  Husbandry changes e.g. nesting sites, temperature, mate, toys.
• Treatment for pre-ovulatory ovarian stasis

  In reptiles only. Ovariectomy needed - always surgical (referral)

  Mating and hormone injections are ineffective once symptoms begin.

  
• Non-obstructive dystocia treatment in birds

  Non-obstructive dystocia:

  • Hypocalcaemia
  • Inadequate husbandry, diet, nesting suite
  • Poor muscle tone.
  • Dehydration.

  Treat with husbandry changes +/- medical treatment first.
• Surgical treatment for egg binding

  Salpingotomy = remove eggs only (can breed again).

  Ovariosalpingectomy = remove oviduct and ovaries

  Both options need referral.

  After the above surgeries, place an oesophagostomy tube in all tortoises for post-op feeds and medication.
• Ovencentesis

  Surgical treatment for egg binding

  • Needle is inserted into an egg and its contents aspirated under GA (via cloaca or percutaneous).
  • Followed by manually moving the egg (milking it along) or deliberately collapsing the egg shell and it removing it piece by piece (or let it be passed piece by piece by the animal).
  • First opinion option (not tortoises or ectopic eggs).
• Husbandry corrections in reptiles.

  Correct husbandry and dietary deficiencies.

  Temperature and humidity requirements may be different/more specific when gravid.

  Bathe and keep hydrated e.g. misting for chameleons and large shallow bowls for tortoises.

  Ensure access to an appropriate substrate/ nesting site for the species.
• Husbandry corrections in birds

  Decrease photoperiod (8-10 hours)

  Remove real/percieved mates. Discourage territorial behaviour.

  Prevent nesting by removing all shredable/ nesting material.

  Reduced the amount and calorie (fat) content of food.

  Increase exercise and foraging time.

  Stop stroking and petting and mouth to mouth actions.
• Routine neutering reptiles

  Not routinely performed. It is only performed when there is a problem that requires surgery as treatment.

  Apart from prolapses, males rarely have problems with their reproductive tract.

  Outside of breeding season/ reproductive activity the reproductive tract in reptiles can be very hard to find.

  Ovaries are diffuse in reptiles, so can be difficult to remove all ovarian tissue/follicles, so no guarantee of future problems.

  Husbandry is key to healthy reproduction
• Routine neutering birds

  Not often routinely performed. It is only usually performed when there is a problem that requires surgery as treatment.

  Particularly risky procedure in birds. The ovaries are firmly attached to the dorsal abdominal wall, the cranial renal artery and the common iliac vein overlay them. Lacerating the common iliac vein can cause life threatening haemorrhage during ovariectomy.

  Hormone implants are seen as the alternative to surgery nowadays.