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Abstract. Microsporidian spores have been detected by Chromotrope 2R and calcofluor stains in fecal samples of three free-ranging human-habituated mountain gorillas in Uganda and in two people who share gorilla habitats. All spore isolates have been identified by PCR with species-specific primers and fluorescent in situ hybridization with a species-specific oligonucleotide probe to be Encephalitozoon intestinalis. Sequencing analyses of the full length SSUrRNA amplified from all spore isolates were identical with Enc. intestinalis SSUrRNA GenBank SIU09929. Sequences generated from a fragment containing the internal transcribed spacer of these isolates were identical to GenBank sequence Y11611, i.e., Enc. intestinalis of anthroponotic origin. A single pathogen genotype in two genetically distant but geographically united host groups indicates anthropozoonotic transmission of Enc. intestinalis. It is highly unlikely that these two identical Enc. intestinalis genotypes were acquired independently by gorillas and people; it is much more probable that one group initiated infection of the other.

Abstract:  The therapeutic effect of halofuginone hydrobromide (Steronol) and spiramycin solubilized (Spirasol) applied to clinical Cryptosporidium serpentis infections in captive snakes was investigated. Pathological changes induced by C. serpentis were typical for snake cryptosporidiosis. Spiramycin induced no significant change in the pattern of shedding of fecal Cryptosporidium oocysts; biopsies and necropsies revealed cryptosporidiosis in gastric mucosa of all spiramycin-treated animals. In all, 8 of 21 (38%) halofuginone-treated snakes stopped shedding C. serpentis oocysts; examination of gastric tissue of 6 of these 8 animals revealed cryptosporidiosis in 2 snakes. Hepatotoxic and nephrotoxic pathological changes induced by halofuginone included focal or multifocal, severe, acute liver necrosis; severe liver hemosiderosis; and bilateral, severe, acute diffuse cortical and tubular necrosis and iron deposition. Postprandial regurgitation associated with midbody swelling, observed in 4 halofuginone-treated and 2 spiramycin-treated snakes at 15 and 21 weeks after drug withdrawal, did not coincide with oocyst-positive feces. Neither halofuginone nor spiramycin treatment produced a satisfactory therapeutic outcome when applied against clinical C. serpentis infections in snakes.

The value profiles of 5 intracellular enzymes, 15 metabolites (with 2 associated ratios), and 3 electrolytes were monitored over time in 9 captive-reared African black-footed penguins (Spheniscus demersus) with different avian malaria clinical status: uninfected, subclinically infected, and clinically infected with fatal outcome. Fatal infections were caused byPlasmodium relictum. Numerous schizonts were visible in the lungs, liver, spleen, and interstitial tissue of the kidneys. The feference ranges of 23 serum clinical chemistry parameters and 2 ratios were established forS. demersus. The mean values obtained for 8 of 23 parameters of the infected penguins were signficantly different from those recorded for the uninfected birds, indicating impaired renal function, hepatic dysfunction, and nonspecific tissue damage related to the infestation with exoerythrocytic schizonts. Analysis of sensitivity, specificity, and negative and positive predictive values (PPVs) showed that gamma-glutamyltranspeptidase (GGTP), alanine aminotransferase (ALT), and creatinine reached PPVs and a specificity over 57% for avian malaria infections in penguins. Creatinine, ALT, and GGTP values should be consulted in evaluation of the clinical malaria status ofS. demersus.

SummaryFive Cryptosporidium‐free Canada geese (Branta canadensis) were individually orally dosed with 3–5 × 106Cryptosporidium parvumoocysts infectious to neonatal BALB/c mice. After intestinal passage, inoculum‐derived oocysts extracted from goose faeces established severe infection in 14 neonatal BALB/c mice (inoculum dose 2.5 × 105/mouse). The inoculum‐derived oocysts were detected in goose faeces up to 9 days post‐inoculation (PI); the number of intact oocysts and oocyst shells shed during the first 3 days PI was significantly higher than for the remaining 6 days PI (P<0.01). Based on acid‐fast stained air‐dried direct wet smears, 62% of the oocysts in goose faeces were intact (oocyst shells constituted 38%) and conformed to morphological features of viable and infectious inoculum oocysts. The fluorescence scores of the inoculated oocysts, obtained by use of the MERIFLUORtest, were identical to those obtained for the faeces‐recovered oocysts (majority 3 + to 4 +). The dynamics of oocyst shedding showed that overall, the birds released a significantly higher number of intact oocysts than oocyst shells (P<0.01) Retention of the viability and infectivity of C. parvumoocysts following intestinal passage through a migratory water‐fowl species has serious epidemiological implications. Water‐fowl can serve as mechanical vectors for the water‐borne oocysts and can contaminate surface waters with C. parvum.As the concentration of Cryptosporidiumoocysts in source waters is attributable to water‐shed management practices, water‐shed protection programme officials should consider water‐fowl as a potential factor enhancing contamination of the source water with Cryptosporidium.

The applicability of ELISA detection of circulating Aspergillus spp. antigen (Ag) and systemic antibody (Ab) of IgG class, and the blood parameter values were evaluated for diagnosis of invasive aspergillosis in Aspergillus spp.-challenged Peking ducks (Anas platyrhynchos). The protective role of Aspergillus spp. IgG was evaluated in Cape shelducks (Tadorna cana) immunized with Aspergillus spp. Ag. Challenged but non-immunized A. platyrhynchos developed invasive aspergillosis on day 21 as demonstrated histopathologically by the presence of fungal microgranuloma in air sacs and lung tissue, with serum antigenemia fluctuating from 65 to 270 ng of 55-kD basic protein Ag per ml. Immunized A. platyrhynchos did not demonstrate Aspergillus spp. serum antigenemia but did show rare histopathological changes in some air sacs associated with fungal inflammation. Although the differences between immunized and non-immunized T. cana in blood evaluation parameters did not differ significantly, immunized birds mounted high Aspergillus spp.-specific IgG titer. There was no correlation between the blood parameter values and post-immunization timepoints in T. cana and in A. platyrhynchos. Intramuscular immunization with Aspergillus spp. mycelial phase cultures Ag provided protection against the pathogens. The lack of relations between blood parameter values and increasing Aspergillus spp. IgG titers (in T. cana and A. platyrhynchos) indicate low applicability of these parameters in evaluation of a bird Aspergillus spp. status. Detection of circulating 55-kDa Aspergillus spp. Ag has high early predictive values for invasive aspergillosis in birds.

Abstract: Hemocytes of the Asian freshwater clam Corbicula fluminea, phagocytosed in vitro infectious Giardia duodenalis cysts. After 15, 30, 60, 90, and 120 min of incubation an average of 22%, 32%, 43%, 54%, and 72% of the cysts were phagocytosed by 22%, 55%, 63%, 81%, and 86% of the hemocytes, respectively. The number of hemocytes showing phagocytosis and the mean number of cysts ingested per hemocyte increased␣significantly over time (P < 0.01); the numbers of nonphagocytosed cysts significantly decreased (P < 0.02). Extrapolation reveals that C. fluminea can retain by phagocytosis an average of 1.6 × 106 G. duodenalis cysts/ml hemolymph. The phagocytic capacity of C. fluminea hemocytes indicates the applicability of this freshwater benthic bivalve for bioindication of contamination of waste waters and agricultural drainage with Giardia cysts.