Spontaneous Cryptosporidiosis in Captive White-Tailed Deer (Odocoileus Virginianus)

Abstract

In August 1994, cryptosporidiosis was diagnosed in a diarrheic fawn from a captive white-tailed deer (Odocoileus virginianus) herd maintained for research purposes at The University of Georgia's Warnell School of Forest Resources in Athens, Georgia (USA). From June through August 1995, 11 captive female white-tailed deer were housed in individual barn stalls where they gave birth to 18 fawns. Feces collected at 2 or 3 day intervals from the 18 neonatal fawns for at least 21 days and from 11 adult females once from 1 to 30 days before fawns were born and on three to 12 occasions after their birth were examined for oocysts of Cryptosporidium spp. Feces from all animals appeared normal throughout the period of examination. Oocysts morphologically indistinguishable from those of Cryptosporidium parvum were detected intermittently in the feces of one adult female from 1 to 25 days after parturition and in the feces of her fawn from 11 to 22 days of age. Oocysts also were detected intermittently in feces from twin fawns from 9 to 20 days of age, but not from their mother. Oocysts from deer were infectious for neonatal mice as determined histologically, and for calves as determined by clinical signs and excretion of oocysts.

Cryptosporidium parvum Infection Involving Novel Genotypes in Wildlife from Lower New York State

“…Based on morphometric analysis, in the previous reports of infections in deer cryptosporidia were designated C. parvum (13,29). In addition, for one of the captive deer isolates, the SSU rRNA gene sequence was identical to the C. parvum genotype 2 sequence (GenBank accession number AF093494).…”

“…Cryptosporidium infection was first reported in white-tailed deer in a captive herd in Georgia in a small sample of neonatal fawns and their mothers; most infections were asymptomatic (13). Recently, the first study of Cryptosporidium infection in wild white-tailed deer was described (29); the prevalence of infection was determined by microscopic methods.…”

“…White-tailed deer (Odocoileus virginianus) are of particular concern in the eastern United States because of their high population densities in both rural and suburban areas, including the watersheds of New York City's CatskillDelaware and Croton water supply systems. Cryptosporidium infection has been reported in both captive and wild whitetailed deer populations in the mid-Atlantic, southern, and western United States (11,13,29). We performed a survey of wildlife in lower New York State; focusing on white-tailed deer and small mammals, to assess whether they might be an environmental source of Cryptosporidium.…”

The Prevalence of Cryptosporidium and Giardia Spp. in Fecal Samples from Free-Ranging White-Tailed Deer (Odocoileus Virginianus) in the Southeastern United States

“…8,9,20,30 However, detection in older animals may be considered by some to be unusual. In cattle, natural infections with C. parvum have been reported in calves as young as 4 days but appeared to be most common around 2 weeks of age.…”

“…8 That study demonstrated that captive WTD can excrete C. parvum oocysts that are infectious for other mammals. However, the role of free-ranging WTD in the epidemiology of cryptosporidiosis could not be inferred from that study.…”