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Domestic Poultry 129

Bacterial Infections
There are many different species in the bacterial genus of Salmonella. Generally speaking,
Salmonella pullorum and Salmonella gallinarum are reportable diseases and cause the greatest
problem for poultry; Salmonella enterica serotype Typhimurium and serotype Enteritidis are
important for the public health aspect. Pullorum (S. pullorum) is egg‐transmitted and causes a
diarrheal disease in young chicks and turkey poults resulting in high mortality. Adult birds are
asymptomatic carriers. Diagnosis is based on disease history and isolation of the bacteria.
Prevention is achieved by purchasing birds from disease‐free flocks, such as participants of the
National Poultry Improvement Plan (NPIP) program. Treatment is not recommended because it
can cause birds to become carriers. Fowl typhoid (S. gallinarum) occurs in chickens, turkeys, and
many other game and wild birds. Fowl typhoid is similar in disease presentation and diagnosis to
pullorum, although mature birds can show clinical signs of fowl typhoid. Prevention is again
achieved by obtaining disease‐free stock. Clinical signs are infrequently observed in poultry
infected with Salmonella enteritidis and Salmonella typhimurium. Flocks can be monitored by
regulatory blood testing and obtaining egg samples or environmental samples for culturing the
organism.
Chronic respiratory disease in poultry (primarily chickens and turkeys) is generally caused by
Mycoplasma gallisepticum infection. Pathogenicity of the organism is enhanced by co‐infection
with other organisms. Clinical signs of respiratory disease develop slowly in a flock and feed con-
sumption drops. Infection of the sinuses is common in turkeys. Serology and identification of the
organism can be used for diagnosis. Contact your veterinarian or local veterinary diagnostic labo-
ratory for testing options. Prevention, as with the Salmonellas, rests with the establishment of a
clean flock by eliminating the infected flock, complete sanitation, and obtaining clean stock. Live
vaccination is available on a state‐by‐state basis. Treatment is expensive, and the disease often
recurs after cessation of treatment. Other important mycoplasmas in poultry include Mycoplasma
synoviae (infectious synovitis) and Mycoplasma meleagridis (venereal infection and airsacculitis).
Colibacillosis is caused by the organism Escherichia coli (E. coli) and is usually secondary to
other infections such as IBV and mycoplasmosis. A wide variety of clinical signs can be observed,
and the organism occurs in most species and age groups. Vigorous adherence to biosecurity and
sanitation programs will effectively prevent the organism from causing disease. Many antibiotics
can be used for treatment, and sensitivity to the antibiotic should be ascertained. Treatment is usu-
ally successful if the disease is in the early stages.

Fungal Diseases
Aspergillosis (brooder pneumonia) occurs in many poultry and nonpoultry species of birds. Birds
under 3 weeks of age are most commonly affected, and infection is obtained from hatchers or
brooders that are contaminated with fungal spores. Morbidity is variable and mortality can be high
in clinically affected birds. Culturing the fungus or demonstration of typical fungal hyphae in fresh
preparations from lesions are used for diagnosis. Prevention is obtained by thoroughly cleaning
hatchers, incubators, waterers, feeders, and ventilation fans and by keeping litter clean and dry.
Treatment is expensive and may not be effective. Ketoconazole and nystatin have been used.

When to Notify State Authorities
Reportable diseases are those diseases that cause severe morbidity and/or mortality, are economi-
cally harmful, or spread very rapidly. Veterinarians and rehabilitators are very important first lines
of defense in identifying reportable and potentially devastating avian diseases such as virulent
Newcastle disease virus (vNDV) and avian influenza. It was a veterinarian in private practice who