POULTRY HEALTH

Pet Chickens and the Vet

It may surprise some people to learn that chickens are in fact the third most common bird presented to avian veterinarians for examination and treatment. More and more people are realising that a few chickens kept as pets or maintaining a larger number for breeding or showing is not only rewarding but also lots of fun. Many breeds of chicken live as long as dogs and cats, they recognize their owners, come when they are called, fit into a routine, have their own individual personalities, and are relatively cheap to maintain.  At the end of a busy day is not only relaxing but probably therapeutic to let the birds out and watch them scratch around.

Getting started

Healthy chickens that are well maintained and fed tend to be pretty problem free. Starting with the right birds is important. Obtaining birds form situations where lots of birds have come together from different backgrounds, such as markets or pet shops, means that the birds have a much higher potential for disease exposure. This is not ideal. It is always much better to buy directly from a breeder and preferably one that has good health management programs in place. It is also much much better if the birds are vaccinated, particularly against Mareks disease and CRD (see below). Reputable breeders will also have effective parasite control measures in place, have had the birds accurately sexed and also established on a nutritious balanced diet.

 

Feeding

Because of the commercial importance of chickens, more is known about their nutritional requirements than any other bird. The commercially available pelleted rations make the provision of a complete nutritious diet easy for pet chicken owners. Base your birds diet on an appropriate commercial ration for their stage of life i.e. starter, grower (up to 4 months), adults maintenance or layer. This diet can be varied by adding grain, table scraps (not dairy products, coffee or tea residues or avocado, rhubarb or onion off cuts) and also by giving the birds the opportunity to forage in the garden (where they will eat at a variety of insects, worms, soil and plant material).

 

Basic health care

Chickens are fairly tough. Provided they have a dry clean place to get out of the weather and are well fed, most tend to be problem free from a health point of view. It is however important to provide good control of parasites. Chicken lice and coccidia (a protozoan parasite of the bowel) are specie specific.  This means that they only infect chickens. Treating all birds simultaneously or new birds prior to entry means these problems can be eradicated. Many of the mites and internal worms however are not species specific and exposure to wild birds provides an ongoing reservoir of infection. Wild birds such as doves and starlings are often drawn to chicken feeding areas. Their droppings and feathers contaminate the environment and are sources of infection for the chickens.  This means that regular treatment for these parasites should be given.

Suggested treatments:

 Worms- Moxidectin 2mg/ml, 5ml/L for 24 hours in the drinking water, or 0.25ml/400gm body weight orally.

Mites- Moxidectin used as above will also kill mites on the bird (which feed off blood). Mites also live in the environment, particularly dry areas such as nests. Therefore simultaneously spraying the environment with a suitable insecticide such as Permethrin 40ml/g, dilute 10ml/L is necessary to achieve control. It is best to spray the pen in the morning of a warm day so that it is dry for the chickens to roost in that night.

Lice- live their entire life on the bird, spray the birds with Permethrin 40ml/g, and dilute 10ml/L. Treat all birds simultaneously.

 Coccidia- toltrazuril 25mg/ml, 0.3ml/kg orally or 3ml/L for 48 hours in the drinking water.

Reproductive issues

Compared to other birds chickens lay a lot of eggs. Sometimes this comes with a cost to the birds health. Breeds that have not been selected for high egg production, such as many of the show breeds and bantams, that are kept as backyard pets often develop laying patterns similar to those of wild birds. In these birds most eggs are laid through spring and early summer. Egg production declines through autumn (when moulting occurs) with only a few eggs being laid through winter. However some of the commercial breeds, such as Isa browns ,if they are kept as pets lay enormous numbers of eggs. This makes them more vulnerable to problems of the reproductive tract. Sometimes as problems begin abnormally shaped eggs or eggs with an abnormal, often roughened surface or eggs with blood on the surface will be passed. Birds with any of these symptoms should be taken to an avian vet. Egg binding (difficulty in or inability to lay an egg), oviduct infections, egg peritonitis (where egg material escapes into the abdomen), post egg laying paralysis (seen as decreased function of the legs) and cancers of the reproductive tract are all common. Affected birds often become quieter than other birds, less interactive, have a reduced appetite, become fluffed, develop a purplish comb, adopt a horizontal posture, lose weight, can develop a distended abdomen or have trouble breathing.

 

Going to the vet

Some people think that it is unusual to take a chook to the vet but it is normal, many people do. In fact it is the normal thing to do when you have an unwell animal. The important thing to have in your mind  when assessing if a bird is unwell and may need to go to the vet is that chickens mask health problems very well and the problem is almost invariably more severe than it appears. In the wild chickens are prey species. The ones that look sick stand out from the crowd and is targeted by predators as an easy catch. Often chickens only look sick when they can no longer compensate for their problems. By this stage the condition is often advanced. The most common reason for treatment failure in unwell chickens is delayed presentation to the vet. If your bird appears unwell it should go to an avian vet straight away. It is disturbing that some people take initial advice from the internet or You tube over that of a qualified avian vet. Delayed presentation and inappropriate treatment can mean the opportunity for a good outcome is lost.

 

Roosters and other council concerns

Most councils have limits on the number of chickens that can be kept and often have additional restrictions on the keeping of roosters. Libido reducing medications are available and the use of rooster boxes is encouraged. Most councils encourage owners to work with their vet to overcome neighbour concerns.

 

Common diseases (that you might have heard of)

Mareks disease – caused by a Herpes virus that transmits from one bird to another, this disease was once extremely common killing 60% of the Australian layer flock annually. Now controlled through vaccination in the first five days of life this disease is still common in unvaccinated birds. The virus induces a cancerous change in a particular type of white blood cell called a T cell. Clinically affected birds develop paralysis of the wings, legs or neck amongst other signs and almost invariably die. It is much better obviously to buy chickens that have been vaccinated.

 

Avian Leucosis- caused by a Retrovirus, this is a complex disease. This virus also targets an immune cell- the B cell and is principally spread by asymptomatic  carrier hens through their eggs. Chicks that hatch from these eggs are infected with the virus and develop the disease.   Birds that become sick always die.  When purchasing birds try and ensure that the parent flock is free of leucosis.

Fowl Pox -   caused by a Pox virus, transmitted by blood sucking insects and fighting amongst infecting birds. Infected healthy adults usually recover in 4-6 weeks. Infected birds develop scabby nodules over the unfeathered parts of the body, particularly the face and beak margins. Chickens are protected through  vaccination which can be given at any age. 

Chronic respiratory disease (CRD) - the common respiratory infection of chickens. Affected birds develop red watery eyes, swollen sinuses and a nasal discharge. Caused by Mycoplasma spp. Chicks become passively infected from their mother or other adults. Once infected, they are infected for life. Appropriate antibiotics can control the disease but not eradicate the organism.  Vaccines, given as an eye drop in the first few days of life and prior to contact with other chickens contain modified  non- disease causing Mycoplasma strains that colonise the birds sinuses and exclude disease causing Myco plasmas. 

Coryza – causes signs similar to CRD.Caused by the bacteria, Haemophilus sp.. Controlled through antibiotics, good management and quarantine.

Infectious Laryngo Tracheitis (ILT) – caused by a Herpes virus that principally inflames the top third of the windpipe leading to difficulty breathing. Controlled through vaccination.

Some unwell chickens do have one of the common infectious diseases, but many have problems that need to be diagnosed and addressed on an individual basis. In a similar way to dogs and cats, pet chickens develop tumours, catch infections, injure themselves and swallow things they shouldn’t.

When an unwell pet chicken is presented to an avian veterinarian, sometimes a thorough clinical examination and the bird’s recent history enables a diagnosis to be made. If not, at least these orientate the diagnostic approach. Looking at droppings microscopically and drawing blood for routine biochemistry (organ function tests) and haematology (red and white blood cell parameters) are common tests that may either enable a definitive diagnosis to be made or indicate further diagnostic tests (such as X-rays) or tests for specific disease (e.g. bacterial culture). Once a diagnosis has been made the correct treatment and control measures can be implemented for the unwell bird and if necessary to protect any other bird in the group.