An 8-year-old, female Kirk’s dik-dik (Madoqua kirkii) housed in a southwestern United States zoo was anesthetized for examination due to declining body condition, hyporexia, poor hair coat, lethargy, and abnormal behavior of shivering and defecating in atypical locations. The only abnormalities noted on physical examination were thin body condition and prominent lung sounds on auscultation. Thoracic radiographs showed a mixed alveolar and structured interstitial pattern throughout all lung lobes. Complete blood cell count and serum chemistry panel revealed a severe leukocytosis due to neutrophilia with a left shift, severe normocytic-normochromic anemia, and severe hyperglobulinemia. Due to the high incidence of coccidioidomycosis in the southwestern United States, all mammalian chemistry samples from this zoological institution are assessed for a coccidioidomycosis titer. This animal was found to have a severely elevated coccidioidomycosis titer of >1:256 with the presence of both IgG and IgM antibodies, suggestive of active infection. Coccidioides immitis is a pathogenic, dimorphic fungi—also known as valley fever. While numerous other taxa1 (including great apes, prosimians, old and new world primates,2 equids, mustelids, and procyonids) have been diagnosed with and treated for coccidioidomycosis, no members of the subfamily Antilopinae have been reported as infected to date. Oral fluconazole therapy was initiated at 5.3 mg/kg daily. Due to insufficient fluconazole levels (4.34 µg/ml) measured one month into treatment, the dosage was increased to 10 mg/kg daily, which eventually resulted in therapeutic drug levels. To date, this dik-dik has been treated for 23 months with resolution of clinical signs and marked improvement in blood work and valley fever titer values. While uncommon in ruminants, coccidioidomycosis is an important differential for systemic disease and pulmonary abnormalities in exotic ruminants housed in southwestern United States institutions.
The authors thank Phoenix Zoo’s animal care and veterinary technician staff for their assistance with this case, particularly the hoofstock keepers for all their efforts in the continued care of this animal.
1. Churgin SM, Garner MM, Swenson J, Bradway DS, French S, Kiupel M, West G. Intestinal coccidioidomycosis in a red coachwhip snake (Masticophis flagellum piceus). J Zoo Wildl Med. 2013;40(4):1094–1097.
2. Goe A, Swenson J, West G, Evans J. Meningoencephalitis with secondary obstructive hydrocephalus caused by probable Coccidioides species in a buff-cheeked gibbon (Nomascus gabriellae). J Zoo Wildl Med. 2013;40(3):781–785.