Thomas L. Deardorff

Contracaecum multipapillatum (= C. robustum ) from Fishes and Birds in the Northern Gulf of Mexico

of the sediment in 1 cc of sterile saline. The results were expressed per mouse. White cell counts for 10 noninfected mice in the second group were 10.5 (+2.04) x 106 per animal, whereas the count in the third group of control mice was 6.4 (+3.5) x 106 leukocytes per mouse. The respective coefficients of variation were 0.19 and 0.55. This indicates a recovery of 64% higher cell counts and a reproducibility 2.8 times greater for the dye method. The mean volume of peritoneal fluid in noninfected mice was 0.28 (?0.08) cc. In 10 infected mice examined by the technique described, the data were 17.1 (?4.1) x 106 white cells, 56.0 (?12.01) x 106 trophozoites, and 1.09 (?0.18) cc of peritoneal exudate per mouse. The dye method provides an accurate assessment of cell and parasite number in the peritoneal cavity by the use of Evans blue as a dilution stain marker. Spectrophotometric absorption curve for the stain showed good absorption at 610 nm. At this wavelength, the yellow color of the FCS was minimal. Evans blue had no noticeable effect on the viability of parasites under the conditions employed. This technique also provides good resolution of differences in cell number and liquid volume in the peritoneum between infected and noninfected mice owing to the marked development of ascites in mice inoculated with T. gondii intraperitoneally. The ability to obtain cell and parasite counts for each infected mouse has an advantage in host-parasite studies by providing a more direct measure of the infection itself than parameters based on number per unit volume. The injected volume (V) may be altered as desired without change in the results, because it is substituted in the equation for the new value. Varying amounts may be especially useful in the evaluation of T. gondii infection in mice of different ages or between different rodent species. The present method has been applied successfully in experiments with a large number of mice. Calculations can be performed with a single desk-top calculator program, cutting down the time of repetitive calculations.

COMMERCIAL BLAST-FREEZING OF THIRD-STAGE ANISAKIS SIMPLEX LARVAE ENCAPSULATED IN SALMON AND ROCKFISH

Sixty-four fish were blast-frozen to -35 C for 15 hr to determine the effects of commercial blast-freezing on the viability of third-stage larvae of Anisakis simplex encapsulated in the muscle and viscera of sockeye salmon (Oncorhynchus nerka) and canary rockfish (Sebastes pinniger). Parallel tests were conducted on larval nematodes in 16 whole (round) salmon, 16 dressed salmon (heads and viscera removed), and 32 whole (round) rockfish. After blast-freezing, 4 in-the-round salmon, 4 dressed salmon, and 8 in-the-round rockfish were examined at 1, 24, 48, and 72 hr. A total of 3,539 dead and 6 live larvae were collected from the fish tissues after standard enzymatic digestion. Salmon were infected with 1,245 of these larvae, and rockfish with 2,300. The 6 live worms, 2 from salmon and 4 from rockfish rounds, were recovered from muscle 1 hr after freezing; they were slightly motile and showed severe internal damage. No viable worms were found at or after 24 hr. The commercial blast-freezing process effectively killed larval nematodes in whole or dressed fish. Market-ready samples of previously blast-frozen silver salmon (O. kisutch) and chum salmon (O. keta) fillets and chum salmon steaks yielded no live worms, thereby confirming the efficacy of this process.

Anisakis simplex: histopathological changes in experimentally infected CBA/J mice

Third-stage juveniles (L3) of Anisakis simplex, surgically implanted into the abdominal cavity of CBA/J mice and necropsied at 7, 14, or 21 days postinfection (PI), embedded in the gut mesentery and only rarely invaded viscera. Histologically, intense aggregations of neutrophils adjacent to the parasites were noted at Day 7 PI. At Day 14 PI, mature granulomata consisting mostly of eosinophils and large numbers of fibroblasts and associated collagen were observed. Granulocytes and occasionally multinucleate giant cells occupied the host-parasite interface. At 21 day PI, lesions displayed the predominance of connective tissue. Multinucleate giant cells were found adjacent to the L3 with eosinophils adjacent to parasite remnants or scattered within the walls of the granulomata. Most L3 were viable at Days 7 and 14 PI; however, at Day 21 PI the L3 were dead and invaded by inflammatory cells. Hematological findings indicated that infected mice had a neutrophilia of varying magnitude regardless of the number of worms implanted. Eosinophil levels as a percentage of the total leukocyte pool in peripheral blood always remained at or below normal limits. On Days 7 and 14 PI, the peripheral blood showed an increase in neutrophils that began to return to normal values at 21 day PI. Conversely, peripheral blood eosinophils decreased on Days 7 and 14 PI and returned to normal values on Day 21 PI. Surgical implantation of A. simplex L3 into mice produced both a hematological and histological picture consistent with that seen in human anisakiasis.

Anisakis simplex: Larval excretory secretory protein production and cytostatic action in mammalian cell cultures

Excretory secretory proteins produced in vitro by Anisakis simplex larvae incubated in Medium 199 or phosphate buffered saline with dextrose are similar with respect to protein content and biological activity. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggested that the molecular weight of the component(s) responsible for inhibition of mitogen induced lymphocyte blastogenesis is between 66,000 and 95,000. In vitro production of excretory secretory protein, approximately 1 microgram/24 hr by a single larva, was sufficient to inhibit lymphocyte blastogenesis. Serum from a human anisakiasis patient reacted with these proteins in immunoblots, indicating that, during invasion of the gastric mucosa, enough of them are produced in vivo to induce an immune response. The excretory secretory proteins significantly inhibited proliferation of transformed mammalian cell lines of lymphoid (P3/X63-Ag8) and epithelioid (HeLa) origin. As in mitogen stimulated lymphocytes, the inhibitory effect was cytostatic rather than cytotoxic. These findings suggest that, in addition to being potent immunogens, larval excretory secretory proteins are produced in sufficient quantity to modulate the host response in anisakiasis.

Seafood-Transmitted Zoonoses in the United States: The Fishes, the Dishes, and the Worms

We live in a parasite-filled world. Nearly every animal—if not parasitic itself— hosts one or more parasitic organisms. Most parasites live in harmony with their hosts and remain of little concern with regard to economics or public health. On the other hand, some parasitic relationships involving humans and domestic animals result in diseases that have a serious impact on the host populations. Examples of such diseases include malaria, African sleeping sickness, and hookworm disease. In areas with heavy infections of such parasites, both human health and the corresponding economic climates are affected.

Terranova ceticola n. sp. (Nematoda: Anisakidae) from the dwarf sperm whale; Kogia simus (Owen), in the Gulf of Mexico

SummaryTerranova ceticola n.sp. is described from specimens in the stomachs of an individual dwarf sperm whale, Kogia simus, which stranded on the beach at Biloxi, Mississippi. It is characterized by possessing a single pair of medial preanal papillae, 38 to 40 pairs of lateral preanal papillae, five pairs of postanal papillae, and spicules 1 to 2% of the body length and by lacking cuticular plates at the posterior anal lip of males. ac]19800820

Raphidascaris camura sp. n., Hysterothylacium eurycheilum (Olsen) comb. n., and comments on Heterotyphlum Spaul (Nematoda: Ascaridoidea) in marine fishes

Raphidascaris camura sp. n. infected the stomach and intestine of Pomatomus saltatrix (type host), from the northern Gulf of Mexico. It is characterized by having the following combination of features: 31 to 40 pairs of preanal papillae, 10 pairs of postanal papillae with the third papilla from the posterior extremity doubled, nearly equal spicules 1.8 to 2.7% of the body length, and lateral alae abruptly curved near their anterior extremity. Additional species of Raphidascaris were examined and are discussed. Hysterothylacium eurycheilum (Olsen, 1952) comb. n. (=Heterotyphlum e.) from Epinephelus itajara in Florida and the Lesser Antilles, previously known from female worms only, is redescribed as is the anterior end of Heterotyphlum himantolophi Spaul, 1927.

RHINEBOTHRIUM DEVANEYI N. SP. (EUCESTODA: TETRAPHYLLIDEA) AND ECHINOCEPHALUS OVERSTREETI DEARDORFF AND KO, 1983 (NEMATODA: GNATHOSTOMATIDAE) IN A THORNY BACK RAY, UROGYMNUS ASPERRIMUS, FROM ENEWETAK ATOLL, WITH PHYLOGENETIC ANALYSIS OF BOTH SPECIES GROUPS

The new species is a member of an apparently monophyletic group within the genus that includes R. flexile, R. walga, R. himanturi, R. burgeri, R. euzeti, R. hawaiiensis, R. urobatidium, R. paratrygoni, R. ditesticulum, R. tetralobatum, R. margaritense, R. biorchidum, and R. spinicephalum. All of these species have bothridia with medial longitudinal septa, a constriction at mid-bothridium, and, primitively, at least 42 loculi per bothridium and 17-22 testes per proglottid. Of the above, the new species is apparently most closely related to R. burgeri, with which it shares an increased number of testes (30-43) per proglottid, a V-shaped ovary, and a muscular genital pore. The new species is distinct by virtue of possessing 94-152 loculi per bothridium--no other known species has more than 78. This is the second report of Echinocephalus overstreeti from a stingray. It represents a new host, U. asperrimus, and a new location, Enewetak Atoll. Phylogenetic and biogeographic analysis of each species group suggests an ancient Tethys Sea-circum-Pacific origin and evolution. This supports the hypothesis of ancient Pacific origins for potamotrygonid stingrays.

HISTOPATHOLOGY INDUCED BY LARVAL TERRANOVA (TYPE HA) (NEMATODA: ANISAKINAE) IN EXPERIMENTALLY INFECTED RATS

Terranova Type Hawaii A larvae, gavaged into the stomach of Wistar rats, demonstrated the ability to invade the stomach and intestinal tissues of the rat without penetrating the serosa. Lesions induced by these third-stage larvae were present in 25 of 37 (68%) inoculated rats. Larvae adhered to the mucosa of the stomach within 1 hr PI. Mucosal ulceration and acute, focal, hemorrhagic areas in the mucosa and submucosa were associated with most worm-penetrations. Reactions of inflammatory tissue occurred from 4 hr to 6 days PI and granulomas occurred by day 7 PI. Indurated craterlike lesions were noted 10 to 15 days PI. Resolving granulomas were present by day 30 PI. Chronic gastric ulcers were observed at day 30 PI.

Behavior and Viability of Third-Stage Larvae of Terranova sp. (Type HA) and Anisakis simplex (Type I) Under Coolant Conditions

This study reports effects of storage at cold temperatures on behavior and survival of third-stage larvae of Terranova sp. (type HA) and Anisakis simplex (type I) in marine fishes. Snappers, caught near the Hawaiian Islands, were examined to determine whether type HA and type I larvae could migrate from the viscera of ungutted fishes into edible musculature when maintained at 12, 8, and 0°C. Our data are suggestive that both type HA and type I larvae possess the ability to migrate. Temperatures of 12, 8, and 0°C had no noticable adverse affect on viability of both larval types within fish tissues; however, both larval types were extremely sensitive to temperatures below freezing. Death of both larval types encysted within Hawaiian snappers occurred by day 4 at -5°C and within 24 h at -10, -15, and -20°C. Other type I larvae, collected from fishes ( Sebastes spp.) imported to Hawaii from the western Pacific, survived for slightly longer periods at -5, -10, -15, and -20°C when compared with type I larvae from Hawaiian fishes. Subjecting Hawaiian snappers to at least -20°C for 1 d and imported rockfishes to at least -20°C for 5 d is recommended to inactivate the living anisakines before ingesting any raw fish products.