Birds - Medical Conditions
A wide variety of cage birds are kept as domestic pets including budgerigars, cockatiels, lovebirds, parrots, cockatoos, macaws, parakeets, mynahs, canaries and finches. Most are fruit and /or seed eaters, a few are insectivorous. Diet is important since malnutrition accounts for a high proportion of the clinical disease occurring in cage birds. Poor nutritional status and mineral deficiencies can compromise the birds immune system and predispose it to infectious disease. Please seek advice on the most suitable dietary content and variety. Cuttlefish or oystershell are an important source of calcium. Vitamin A is essential for proper functioning of the immune system and is plentiful in such foods as green vegetables, carrot and sweetcorn. All diets based purely on seeds are deficient in vitamin A.
Obesity is a frequent cause of illness in cage birds, especially those kept singly with little exercise. Sunflower, safflower seeds and peanuts can be addictive to some parrots and dietary change can be difficult but is essential since these are high in fats and oils. Diets based purely on these foods result in fat deposition in the liver and blood vessels causing fatty liver disease and arteriosclerosis. Encourage birds to eat a wide variety of foods and good proprietary supplements can also be provided if required.
A stimulating environment is important to prevent boredom which can result in feather plucking. This can be a serious problem especially in birds kept singly.
Sick birds generally all present with similar symptoms, dull, lethargic, and 'fluffed up'. They are good at hiding signs of illness to prevent bullying from other birds in a flock, it means that they are generally seriously ill by the time they are presented at the vets surgery. Prompt attention is important.
This disorder occurs in adult egg laying hen birds. It is caused by the obstruction of the genital tract by an egg or material associated with inflammation of the oviduct (egg peritonitis).
Lowered blood calcium levels during formation of the eggshell can cause progressive muscle weakness and paralysis leading eventually to death. The egg may be palpable within the abdomen. The birds are dull, fluffed up, often sitting on the floor of the cage.
It is important to help the bird pass the egg as soon as possible, this may be carried out simply by cleaning and lubricating the vent area, or it may prove to be more difficult. Initial treatment involves warming the bird, and administering calcium, usually in the form of intravenous or subcutaneous injection sometimes along with oxytocin. Manual removal of the egg through the cloca by collapsing the shell carries significant risk but may be necessary. X-rays can help to confirm the diagnosis along with blood sampling of calcium levels. It is important to correct any dietary deficiencies that may have predisposed to this problem. If the egg cannot be passed normally it may be necessary to consider surgical correction by means of a hysterectomy.
Egg peritonitis is a condition caused by leakage of the yolk material into the abdominal cavity and is often associated with other reproductive problems.
Diarrhoea and vomiting are the two most common presenting signs of intestinal disease in birds. Abnormal droppings can be caused by liver disease, nutritional imbalance, bacterial, viral or chlamydial infection, pancreatitis, or parasites.
This is often a symptom of more generalised bacterial infection, since regurgitation, crop stasis and diarrhoea are frequently associated with bacterial septicaemia. Bacteria such as E.coli, Klebsiella, Pasteurella, Salmonella, Clostridia and Mycobacterium spp have all been recorded. Supportive therapy is crucial to successful treatment, fluid supplementation may be required and/or tube feeding if the bird is anorexic. Antibiotics such as enrofloxacin should be used. Oral dosing or injection is preferable to medicating through the drinking water to prevent variability in the dose ingested. It may be necessary to use probiotics after recovery to aid the re-establishment of normal bacterial flora of the gut.
Inflammation or infection of the pancreas can cause diarrhoea in psittacine birds but is difficult to diagnose and may only be discovered at post mortem. It may be associated with diabetes mellitus.
The proventriculum is first part of the stomach in birds. Proventriculitis as a result of infection with Candida or Megabacterium spp can occur in birds, inappetance with diarrhoea, vomiting, and passage of undigested food are common signs. Treatment is with ketoconazole and probiotics.
This may cause the bird to attempt to regurgitate, the bird may show interest in food without attempting to eat. The contents of the crop can be softened with vegetable or mineral oil, or the crop emptied under anaesthesia and flushed out.
This is usually caused by infection with bacteria, fungi or protozoal organisms. The crop becomes flaccid, the bird inappetent and may loss weight. An increase in thirst is common. Low dietary Vitamin A can predispose to this problem. The treatment depends on the specific infectious agent causing the problem but Trichomoniasis is common in budgerigars and metronidazole is effective. Spread of the infection to other sites in the body is possible and respiratory infections are a common complication.
Other major problems will present with vomiting and /or diarrhoea, liver disease, Psittacine Proventricular Dilatation Syndrome, papillomatosis, crop burns, Sour crop etc. It can also be a normal physiological response particularly in hand reared birds where regurgitation is a part of normal courtship behaviour. It is important to have your bird examined by a vet in order to differentiate between the various causes.
Normal preening in birds can occasionally be taken to an extreme form resulting in self mutilation with an exaggerated, aggressive chewing and plucking of feathers.
Occasionally birds will become inappetent and can lose condition. Differentiation of normal grooming from abnormal plucking is important, in birds plucking feathers the feather will not be deformed or discoloured and they are lost from areas that the bird is able to reach.
The common causes of feather plucking are:
- Boredom and/or neurosis.
- Malnutrition, poor husbandry and hormonal imbalance create poor quality feathers which will often be plucked.
- Bacterial or fungal infection infection of the feather follicles.
- Feather mites.
Neurosis is a common cause of feather plucking, especially in birds kept singly with little opportunity for social interaction. Correcting behavioural problems and vices can be difficult. Attempts should be made to enrich the birds environment and provide mental and/or social stimulation. The use of toys, mirrors and unusual foods can help to achieve this, and possibly the introduction of another bird. Frequent moving of the cage to different locations and the use of natural branches for perching are recommended. The level of nutrition should be improved to allow growth of replacement feathers, particular attention should be given to the calcium, protein and energy levels. Elizabethan collars may be used to physically prevent the bird being able to pluck feathers, and may need to be left on the bird for up to 2 months to allow complete feather regrowth. A hide to provide some privacy should be included in the cage and daylight hours should not extend beyond the normal level of 8-12 hours (some birds are kept in light environments for much longer). Birds should be sprayed regularly or allowed to bathe.
Correction of malnutrition or treatment with antibiotics, antifungals, or antiparasitic drugs may be needed.
If these measures do not help then drug or aversion therapy may be required and this is best discussed with your vet on an individual case basis.
Articular gout is common in budgies and presents as creamy white nodules under the skin associated with the limb joints. These masses can be extremely painful causing difficulty in perching. Treatment cannot unfortunately cure this problem, and is only palliative. The cause is the collection of urate crystals in these masses, and in a few individuals these crystals can also be deposited within the internal organs. Dehydration, high protein diet and concurrent kidney disease are all contributory factors in the development of gout.
Anti inflammatory drugs may be of use along with the administration of allopurinol. Lowering the protein intake and increasing water consumption may also be of value. This is easiest achieved by giving plenty of fruit and fresh green food.
Many species of non pathogenic feather mites can infest birds but two mites in particular are of significance.
Dermanyssus gallinae: the 'red mite' can be found on budgies, generally more active at night, the affected birds should be removed from the cage during the day and the cage thoroughly cleaned using an approved product (ask your vet).
Cnemidocoptes pilae: infection with this mite can result in crusting growths around the beak, with deformity and overgrowth of the beak itself. It is particularly common in budgies and cockatiels. The mite burrows into the skin and lives entirely within the keratin layer interfering with the growth of the beak. The skin around the eyes and the legs and feet are also susceptible and may develop a scaly, thickened appearance.
There are multiple causes of breathing difficulty in birds such as bacterial, viral, fungal, and parasitic infection, allergic and nutritional problems and finally cancerous masses within the chest.
Bacterial Respiratory Disease
A large number of organisms can infect the respiratory tract of birds causing sinusitis, rhinoliths (blockage of nasal passages), abscesses, and air sacculitis. Treatment with antibiotics, and /or flushing out the sinuses and nasal passages is required. Vitamin A supplementation may be required and the birds environment should be checked to ensure the temperature, humidity and ventilation are adequate.
Viral Respiratory Disease
Influenza and paramyxovirus can cause a varying severity of problem. Influenza can be transmitted to parrots from humans and vice versa and paramyxovirus can also be responsible for neurological disease. There are also avian pox viruses which can cause sinusitis.
This disease is caused by Chlamydia psittaci and often presents as a mild respiratory infection but many birds can be asymptomatic carriers. The clinical signs associated with this problem are non specific and can vary considerably in severity. Mortality can be high and spread to humans is possible. Long term antibiotic treatment may be required in an attempt to eliminate the infection (up to 45 days of oxytetracycline).
Fungal Respiratory Disease
Aspergillosis is the most common fungal respiratory infection of birds. Often develops when the bird is debilitated with another disease problem, stress, or malnutrition. It should always be suspected in a chronically ill bird with respiratory disease. The infection usually develops within the air sacs and is usually a chronic problem. It can be exacerbated by a damp environment. Treatment with antifungal drugs can be attempted but is often unsuccessful.
Parasitic Respiratory Disease
- Trichomoniasis: occurs mainly in budgies, develops as a creamy deposit around the mouth and 'gurgly' breathing. Treatment is with metrondiazole.
- Syngamus trachea: generally only seen in aviary birds. Parasite lives in the windpipe.
- Sternostoma trachaecolum: this mite lives in the respiratory tract of canaries and finches, occasionally budgies. It can be treated with ivermectin or levamisole but the mortality rate is high.
Nutritional Respiratory Disease
Both vitamin A deficiency and iodine deficiency have been implicated in causing respiratory disease.
Allergic Respiratory Disease
Asthma does occur in birds and is often diagnosed on the basis of response to treatment with corticosteroids.