Giardiasis in laboratory-housed squirrel monkeys: a retrospective study.

Giardia infection was diagnosed in a 1.5-year-old, group-housed, female squirrel monkey with diarrhea. A retrospective study was undertaken to evaluate the incidence of Giardia in the 190-member colony. Records were analyzed to determine whether any one of the following conditions applied: the animal had clinical signs referable to the gastrointestinal system; a fecal examination for ova and parasites was performed; gastrointestinal parasitism was revealed by necropsy; or a culture of samples from the gastrointestinal tract was performed. Analysis revealed a total of 19 monkeys, 68% (13/19) of which had gastrointestinal clinical signs. Giardia cysts were recovered from 33% (4/12) of monkeys with gastrointestinal signs in which fecal examinations were done. The yearly incidence of diarrhea in the colony was low at 0.61%; however, 33% (2/6) of the monkeys with diarrhea were positive for Giardia. Six animals had blood in the feces or rectal prolapse, in the absence of diarrhea, and 30% (2/6) of these animals were positive for Giardia. Of six animals without gastrointestinal clinical signs, 50% (3/6) had giardiasis, which was listed as an incidental finding. In light of these findings, an additional 16 healthy animals were examined for Giardia. Giardia cysts were recovered from 50% (3/6) of males and 70% (7/10) of females from which samples were obtained. Additionally, clean water consumed by the animals was negative for Giardia cysts, and facility waste water was positive. To our knowledge, this is the first report of giardiasis in squirrel monkeys.

Sinoatrial node arteriosclerosis in two young dogs.

Two 11-month-old 7-kg unrelated female Beagles had clinical signs referable to the cardiovascular system. Histologic studies in both dogs revealed strikingly similar findings of sclerosis of the arteries of the sinoatrial node. Histologic changes included intimal thickening and fibrosis, with marked luminal narrowing; medial hypertrophy, fibrosis, and smooth muscle cell proliferation; and elastic fiber disruption and reduplication. Possible differential diagnoses for this condition included systemic necrotizing vasculitis (canine pain syndrome), coronary polyarteritis, and atherosclerosis.

Epidemiologic and immunologic characteristics of Streptococcus equi infection in foals.

A 2-phase study was performed to characterize the effects of Streptococcus equi infection in unexposed and previously exposed foals. In phase I, 22 weanling foals involved in a naturally occurring S equi epizootic were studied, along with a comparison group of 11 unexposed foals, matched for age, sex, and breed. Six months later (phase II), an epizootic was experimentally induced in previously exposed and unexposed foals from phase I. The prevalence and duration of clinical signs, the relative risk of developing disease, bacteriologic culture results, hematologic responses, and mucosal and serum immunologic responses were determined. Disease protection in phase-I and -II foals was associated with high values for serum S equi M protein-specific IgG at the onset of the epizootic (P < 0.02 for phase 1 and P < 0.01 for phase II), and with a rapid (within 2 weeks of exposure) mucosal S equi M protein-specific IgG response (P < 0.05 for phase I and P = 0.01 for phase II).