Pigeon Fever
Pigeon fever is a disease with
high prevalence in the southwestern United States where it is primarily
seen in the summer and fall months. Despite the name, it has
absolutely nothing to do with pigeons other than the fact that affected
horses often develop a swollen "pigeon breast" due to abscess formation
in the chest area. Pigeon fever is caused by a specific bacteria
calledCorynebacterium pseudotuberculosis which can survive in the soil
for more than 8 months. It is believed that the bacteria is
transmitted from one horse to another by flies feeding on the exudate
from draining abscesses or by contamination of superficial skin wounds
by soil containing the bacteria.
Although pigeon fever abscesses can occur anywhere, the most common locations are the chest and ventral abdomen, the sheath of males and the udder of mares. These infections are often noticed first as a generalized swelling along the belly or on one side of the chest. This progresses to reveal a smaller, more discrete, very firm swelling which is the abscess itself. These swellings can be quite painful and cause signs of lameness and stiffness if they are near a leg. About 25% of horses will also develop a fever and may go off feed.
TREATMENT
Once they come to a head, abscesses must eventually be opened and drained to the outside. It may take from one to several weeks before an abscess matures enough to be drained. Hot water compresses applied for 10-15 minutes twice daily and application of Numotizine or ichthammol ointment can hasten the maturation process. Antiinflammatory drugs such as phenylbutazone can be given to relieve pain and swelling as necessary. Antibiotics will delay the maturation process and are usually not given to horses with pigeon fever. As it matures, the abscess will develop a soft area in the center, the skin will develop a bruised appearance and the hair will fall out. The abscess may then rupture spontaneously or be opened with a surgical blade. Once open and draining, the abscess should be flushed once or twice daily with dilute Betadine solution. If good drainage has been established, the abscess will usually heal within two weeks without complications. The spread of pigeon fever abscesses to internal organs is a serious complication that occurs in about 8% of affected horses, and requires long term antibiotic therapy.
PREVENTION & CONTROL
Steps you can take to reduce the occurrence and spread of pigeon fever:
1. Control flies which can cause ventral midline dermatitis and spread the disease
2. Reduce contamination of your property by having abscesses lanced and drained under controlled conditions rather than allowing them to rupture in pasture
3. Confine horses with draining lesions to a stall with daily disinfection of lesions, fly control, and proper disposal of contaminated bedding
Although pigeon fever abscesses can occur anywhere, the most common locations are the chest and ventral abdomen, the sheath of males and the udder of mares. These infections are often noticed first as a generalized swelling along the belly or on one side of the chest. This progresses to reveal a smaller, more discrete, very firm swelling which is the abscess itself. These swellings can be quite painful and cause signs of lameness and stiffness if they are near a leg. About 25% of horses will also develop a fever and may go off feed.
TREATMENT
Once they come to a head, abscesses must eventually be opened and drained to the outside. It may take from one to several weeks before an abscess matures enough to be drained. Hot water compresses applied for 10-15 minutes twice daily and application of Numotizine or ichthammol ointment can hasten the maturation process. Antiinflammatory drugs such as phenylbutazone can be given to relieve pain and swelling as necessary. Antibiotics will delay the maturation process and are usually not given to horses with pigeon fever. As it matures, the abscess will develop a soft area in the center, the skin will develop a bruised appearance and the hair will fall out. The abscess may then rupture spontaneously or be opened with a surgical blade. Once open and draining, the abscess should be flushed once or twice daily with dilute Betadine solution. If good drainage has been established, the abscess will usually heal within two weeks without complications. The spread of pigeon fever abscesses to internal organs is a serious complication that occurs in about 8% of affected horses, and requires long term antibiotic therapy.
PREVENTION & CONTROL
Steps you can take to reduce the occurrence and spread of pigeon fever:
1. Control flies which can cause ventral midline dermatitis and spread the disease
2. Reduce contamination of your property by having abscesses lanced and drained under controlled conditions rather than allowing them to rupture in pasture
3. Confine horses with draining lesions to a stall with daily disinfection of lesions, fly control, and proper disposal of contaminated bedding
