Veterinary Tidbits - Pigeon Fever

Etiologic Agent:  Bacteria, Corynebacterium pseudotuberculosis

Mode of Infection:

¨    Through skin or mucous membranes

¨    Skin abrasions

¨    Biting insects (flies, gnats)

Seasonality:

¨    July thru January

¨    External abscesses – mostly Sept, Oct, Nov

¨    Repeat/Internal abscesses – Nov, Dec, Jan

¨    Recurrence/Internal abscessation usually within 3-6 months

Symptoms/Clinical Signs:

¨    External abscesses – chest, sheath, udder, ventral abdomen, side of face, neck, shoulder, hip

¨    Internal abscesses (<10%) – lungs, liver, spleen, kidney, axillary region etc.

o       Typically a lymph node or lymph vessel

¨    Swelling/Edema – ventral abdomen, limbs, sheath, udder, chest

¨    Lameness

¨    Rupture w/ drainage or just oozing of serum

o       Thick, caseous, white pus; non-odorous

¨    +/- fever

¨    +/- anorexia

¨    listless

¨    Internal abscesses = fever, lethargy, anorexia, weight loss, abdominal pain, abortion, inc. HR, inc. RR

o       30% Fatal, 100% Fatal if not treated

Diagnosis:

        Clinical signs, bacterial culture of pus, ultrasound

            SHI serum titers ≥ 512  (Synergistic Hemolysin Inhibition)

            PCR

            Basic Blood work:

¨    inc WBC (elev. Neutrophils)

¨    inc Fibrinogen

¨    inc TP (globulins fraction)

¨    dec HCT (anemia)

Treatment:

¨    Lance/flush abscesses whenever possible

¨    Hot packs, poultice

¨    Antibiotics (internal abscesses require long-term)

¨    Anti-inflammatories

¨    Immune Stimulants

Prevention:

¨    No vaccine!!

¨    Fly control

¨    General environmental cleanliness

¨    Varying levels of immunity:

1.      No infection

2.      lymph node abscesses

3.      multiple abscesses

4.      internal abscesses

 

¨    Endemic in certain areas – new horses, young horses, aged horses, immune compromised at greatest risk

 

¨    Contagion –

o       Not contagious in the typical ways

o       Does not transfer horse to horse

o       Fly bites occur in summer & may take weeks/months to show clinical symptoms

o       May show up all of a sudden – swelling, pain, etc.