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This paper presents quality assurance data and quality control data on the recovery of Ascaris suum eggs from various biosolid matrices: acid-treated, alkaline-treated, amended-soil blended, and lagoon stored biosolids. Over a period of years, the same procedure, the "Tulane Method," was performed on different matrices, and in this work, the data collected on the recovery of the eggs from the different matrices is examined and compared. The egg recoveries are discussed in terms of precision (the comparison of the recovery of eggs from a sample processed in duplicate) and in terms of accuracy (the percentage of eggs recovered from a sample to which eggs were added at the beginning of the extraction procedure). This form of quality analysis/control is typically called the "Split/Spike" method. This method of biosolid processing for helminth egg recovery had an overall accuracy of about 60% or greater and a percent variation from the mean density (an indirect method of assessing precision) of only 3-35%.

Mountain gorillas (Gorilla gorilla beringei) are critically endangered, remaining only in two isolated populations in Central Africa. The objective of this study was to determine the prevalence and intensity of intestinal parasites in a single group of mountain gorillas in Bwindi Impenetrable National Park, Uganda over 7 weeks from June to August 2000. Fecal samples were collected from night nests and transported in formalin for examination at Cornell University and the Centers for Disease Control. All fecal samples were examined microscopically for parasitic larvae, cysts, and eggs. The following were found: strongylid eggs, Probstymaria sp. larvae, and two parasitic nematode larvae that were not identified. Additional examination techniques will be used to further examine the fecal material specifically for protozoan cysts. An increasing threat to this group of gorillas is the presence of local field assistants and researchers. We found no evidence of human parasites in the fecal samples from this gorilla group.

The efficacy of moxidectin injection (ProHeart 6 Sustained Release Injectable for Dogs, Fort Dodge Animal Health) against naturally acquired infections of Toxocara canis was compared with that of milbemycin oxime/lufenuron tablets (Sentinel Flavor Tabs, Novartis Animal Health). Eighteen dogs with naturally acquired infections of T. canis were ranked by egg counts and randomly assigned to treatment with moxidectin (170 micro g/kg), milbemycin (500 micro g/kg)/lufenuron (10 mg/kg), or to an untreated control group (six dogs per treatment). Dogs were euthanized 7 days after treatment for recovery, identification, and enumeration of parasites by species. There was no apparent efficacy for moxidectin against T. canis. Conversely, milbemycin oxime/lufenuron was 91.5 % effective against naturally occurring infections of this canine parasite.

Efficacy of moxidectin injection (ProHeart 6 Sustained Release Injectable for Dogs, Fort Dodge Animal Health) against naturally acquired infections of Trichuris vulpis was compared with that of milbemycin oxime/lufenuron tablets (Sentinel Flavor Tabs, Novartis Animal Health). Eighteen dogs infected with T. vulpis were ranked by egg counts and randomly allocated to treatment with moxidectin (170 micro g/kg), milbemycin (500 micro g/kg)/lufenuron (10 mg/kg), or to an untreated control group (six dogs per treatment). Dogs were euthanized for worm counting 7 days after treatment. Efficacy of milbemycin/lufenuron against T. vulpis was 99.6 %, compared with 67.5 % for moxidectin. The commercial formulation of milbemycin oxime/lufenuron provided excellent control of whipworm infection, whereas moxidectin demonstrated variable efficacy against this parasite.

The effects of freeze-thaw events on the inactivation of Cryptosporidium parvum oocysts in soil were examined. Oocysts were inoculated into distilled water in microcentrifuge tubes or into chambers containing soil the water content of which was maintained at 3%, 43%, or 78% of the container capacity. The chambers and tubes were then embedded in 3 soil samples from different aspects of a hillside landscape (Experiments 1 and 2) and in 3 distinct soil types (Experiment 3) and frozen at -10 C. Containers were thawed every 3 days for a period of 24 hr in 1-9 freeze-thaw cycles over 27 days (Experiments 1 and 2) and 2-5 freeze-thaw cycles over 15 days (Experiment 3). Oocyst viability was measured using the fluorescent dyes 4'6-diaminidino-2-phenylindole and propidium iodide. Inactivation rates were greater in soils than in water and greater in dry soil than in moist and wet soils. Soil type showed no effect on inactivation. Oocysts subjected to freeze-thaw cycles had inactivation rates not significantly different from those of oocysts subjected to -10 C under static conditions. The results indicated that 99% of oocysts exposed to soils that are frozen at -10 C will become inactivated within 50 days whether or not freeze-thaw cycles occur.

A kinetics enzyme-linked immunosorbent assay (ELISA) and a single-read ELISA for the detection of ovine anti-Toxoplasma gondii IgG were developed and optimized. During the kinetics assay, 3 optical densities were obtained for each serum sample at intervals of 45 seconds, and the results were presented as average slopes (replicates of 2) of the reaction rate between bound enzyme and substrate solution. The kinetics ELISA was stopped 5 minutes after dispensing the substrate to constitute the single-read ELISA, and the results were presented as average optical densities for duplicates of each sample. Performance of the assays was evaluated using the modified agglutination test (MAT) as the "gold standard." There was a high level of agreement between both ELISAs and the MAT, as measured by Pearson correlation coefficients, kappa statistics, and the area under the receiver operating characteristics curves. The single-read ELISA was as accurate as the kinetics ELISA, with a sensitivity of 89% and a specificity of 96%.

Cryptosporidium parvum oocyst viability was determined by a dye permeability assay using a flow cytometric method. Oocysts were inoculated into small chambers with soil and biosolids. Oocysts extracted from soil and biosolids were then stained with propidium iodide (PI) and labeled with a fluorescein isothiocyanate (FITC)-conjugated monoclonal antibody. The oocyst population in each sample was determined using forward and side scatter plots, then further analyzed with fluorescence. A red and green fluorescence detector using gates established single populations of unstained, PI-stained, or FITC-labeled oocysts. No statistical difference was observed between viability of oocysts extracted from soil and biosolids as determined by either flow cytometry or microscopy. The location of excysted oocysts was changed in forward and side scatter plots. Results indicated that, although oocysts are not identified if they excyst, the flow cytometric method could be used to determine oocyst viability from spiked environmental samples.