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The Closed Aviary
Concept
Dave J. Rupiper DVM
Kenneth T. Briggs PhD, DVM
The Closed Aviary Concept (CAC) is a system of specific management principles by
which aviculturalists maintain their aviaries in a disease-free state. The basis
of these principles is to prevent the spread of disease via the most common routes;
newly acquired birds, food sources, water sources, litter material and the owner.1,2
The CAC is exactly as its name implies --closed. Once the flock is free of disease
it is maintained that way. The first principle involves establishing a healthy flock.
This is usually accomplished by a yearly examination of the aviary by an avian veterinarian.
The veterinarian should first determine that the aviary can, in fact, become 'closed.'
The avian veterinarian will examine the housing, ventilation, water sources, food
sources and storage, and check for pests and rodents within the breeding aviary.
The nursery will be examined and the incubator, eggs, chicks and records closely
scrutinized. Last, biosecurity methods will be examined to be certain disease can
be monitored. Biosecurity principles employ cleaning, disinfection, vaccination,
foot baths, visitor limitations, boots and sometimes protective garments. Biosecurity
monitoring utilizes tests to evaluate the flock for the presence of disease, and
may include; fecal examinations, crop swabs, fecal cultures, other cultures and ocassionally
blood tests and autopsies (necropsies).3
Once the aviary has been certified disease-free by the avian veterinarian, it can
be maintained that way using the CAC principles. First, all supplies entering the
aviary should be clean and free of disease. This includes the water source, food
source, litter material and anything else entering the premises. Three measures of
biosecurity should be observed at this point. The person feeding should be 'clean':
infective organisms are left outside by stepping through a footbath and wearing protective
clothing. Additionally, the food storage should be a separate, 'clean' area (ie.
metal storage container, different rodent free building, etc.).4
Next, foot traffic should flow from the outside to the footbath, feed storage, breeding
birds, nursery and weanlings, isolation birds and finally quarantined birds.5 This
pathway follows from the 'cleanest' birds to the 'dirtiest' birds and prevents unnecessary
cross-contamination. Not only do the supplies follow a pathway but also the birds
(see accompanying diagram).
At this point, the aviary should be viewed as a six compartment system, as follows:
Food Storage, Breeding Birds, Nursery and Weanling Birds, Isolation, Quarantine,
and Laboratory. The only way a bird enters or re-enters the aviary is through Quarantine.
Quarantine should be differentiated from Isolation, which is used for in-house ill
birds. Quarantine is for new birds and those returning from shows, races and other
trips to the outside world. The only reason a bird enters the breeding aviary is
for the purposes of reproduction. During the 30-45 day period in quarantine, the
new bird must pass diagnostic tests to be accepted as a breeding bird. Depending
on your resources and previous disease problems, these tests may be as simple as
casual observation or as complex as obtaining cultures, chemistry tests and serologic
testing.1,3
After Quarantine and Laboratory, the bird may enter the Breeding flock with the ultimate
goal of producing offspring. The offspring will be housed in the Nursery and Weanlings
section and eventually be sold, retained as breeding stock or in the case of pigeons
and doves; shown, raced and flown.
Ocassionally disease may strike even the closed aviary from unavoidable sources:
contaminated feed, water and litter as well as insect and rodent pests. In these
cases, affected birds are placed in Isolation and must earn their way back into their
compartments by passing diagnostic tests. Isolated birds should not be housed with
quarantined birds as they are still members of the closed aviary.
Last, the owner exits the closed aviary through foot baths to prevent infecting other
aviculturalists' aviaries. Birds exit the aviary only through sale of breeding birds,
sale of weanling birds, defaulting during quarantine, and by death. Columbids are
an exeption in that they are shown, flown and exhibited but must still enter through
a quarantined area.
Let's examine the CAC by comparing two aviaries, one 'open', the other 'closed'.
In the 'open' aviary we can begin at any state of flock health; from disease-free
to disease-ridden. It is an easy system to maintain because there are no rules for
flow of materials, birds or people traffic. No quarantine, no delays in introduction
of new stock from the ourside, no restrictions on contact beween birds, and no 'down
time' for birds returning from shows or races. We can all jump ahead to the logical
conclusion should disease strike within the flock or enter with a newly acquired
bird: almost all birds will eventually come in contact and we've got a major 'brushfire'
to put out! Of course, almost no one pushes their luck with such and 'open' flock--
we all take some steps to prevent acquisition and transmission of disease. However,
epidemiologists (veterinarians and others with a 'population approach' to disease
control) and all large poultry growers will tell you that the closer you can come
to a CAC, your flock will healthier and your expenditures for disease control will
be less.
In summary, disease can be halted by employing the CAC to any aviary, flock or loft
of birds. Emphasis should be placed on establishing a clean, healthy flock and limiting
the birds' exposure to outside contaminants. The closer we approach the Closed Aviary
Concept in our own lofts and aviaries, the lower will be our costs associated with
disease control and prevention with drugs. And, the healthier will be our birds.
For further information regarding avicultural management principles, contact your
local avian veterinarian.
References
1)Speer BL: Personal communication, Oakley, CA, 1991.
2)Speer BL: Avicultural Medical Management. Proc of Parrot Management Seminar, Concord,
CA, Feb. 1991., Pub Avian Research Fund, Alamo , CA, pp 125-152.
3)Nicholas Turkey Breeding Farms: adapted from Breeder Management Guide, Sanitation
Sect.,
Nicholas Turkey Breeding Farms, Sonoma, CA, 1991, pp 1-3.
4)Flammer K: Aviculture Medicine Of Psittacine Birds. in Veterinary Clinics
Of North America Symposium On Caged Bird Medicine, WB Saunders Co., Philadelphia,
1984, Vol 14, N 2, pp 381-386.
5)Flammer K: Aviculture Management. in Clinical Avian Medicine And Surgery,
Harrison GJ (ed), WB Saunders, Philadelphia, 1986, pp 601-612.
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