Avian Serology/PCR

Avian Serology/PCR

Testing available and recommended sample types:

TestSample required
*Chlamydia psittaci PCRCloacal swab
*Psittacine Beak and Feather Disease PCRBlood or blood feather
*Polyoma virus PCRBlood or blood feather
*Mareks disease PCRBlood or blood feather
SexingBlood spot on filter paper or blood feather

 * can be done individually or as part of the Avian Panel

Chlamydophila (Chlamydia) psittaci

Chlamydophila psittaci infection can be the cause of fever, anorexia, lethargy, diarrhoea, excretion of green to yellow urates and occasionally shock and death in birds. Infection can be associated with conjunctivitis, enteritis, pericarditis, air sacculitis, sinusitis, coelomitis, hepatitis and splenitis. The importance of this infection in birds is enhanced by its zoonotic potential. C. psittaci infection has been demonstrated in over 460 bird species with the highest infections rates reported in psittacine birds and pigeons.  Survivors of infection can become asymptomatic carriers. Transmission is from close proximity to another infected bird. The bacteria are shed in nasal secretions and faeces – faecal shedding is intermittent and can be activated by any cause of stress. The organism can survive in the environment for several months if protected by organic debris. Predator or scavenger species can become infected through consumption of the carcass of an infected bird. Nest transmission is possible through regurgitation feeding and via biting/blood-sucking arthropods.

Human infections (psittacosis) occur most commonly from inhaling aerosolized organisms from urine, respiratory secretions or dried faeces. Beaks to mouth contact, a bite from an infected bird or handling the plumage of an infected bird are other possible sources of infection. Appropriate protective equipment should be used if performing a post-mortem on an infected bird.

Psittacine Beak and Feather disease (PBFD)

PBFD is caused by beak and feather virus which is from the family Circoviridae. Infection with this virus causes chronic feather dystrophy and loss, beak deformities, occasionally immunosuppression and death. Death in chronic cases is often due to secondary infections associated with immunosuppression. There are acute and peracute forms which can cause sudden death. Parrots that are known to be particularly susceptible to PBFD include, Cockatoos, Ringneck parakeets, Eclectus Parrots and Lovebirds but all parrot breeds should be considered at risk.  Any psittacine bird with chronic feather loss should be tested for this infection.

Polyoma virus (Budgerigar Fledgling Disease)

Polyoma virus in birds can be seen clinically as sudden death, neurological signs, abdominal distension (hepatomegaly or ascites), petechial to widespread haemorrhage or failure of development of normal feathers. All psittacine birds can be infected however fledgling and juvenile birds are most susceptible. Chronic, subclinical infection with intermittent viral shedding is common in birds that recover from acute infection. Infection is most commonly due to contact with another infected bird – the virus is shed in feather dander and faeces. The virus can remain stable in the environment for long periods.

Marek’s disease

Caused by Gallid herpesvirus-2, Marek’s disease is a highly infectious, wide spread infection in chickens. The viral incubation period is 4-6 weeks and flock mortality is reported to be 10-50%. Infection is most common in young flocks. Clinical signs include hind limb or wing paralysis, dyspnoea, depression, weakness, tumors on feather follicles, blindness and a withered comb. Most clinical signs are associated with the development of T cell lymphoma and the infiltration of lymphocytes into tissues and nerves. Infection with Marek’s disease also causes immunosuppression and increases susceptibility to secondary infections. The virus is shed in the feather dander and droppings or any secretions. The virus can persist for long periods in poultry yards.