Para_b90_02.405-407.tp

J. Parasitol., 90(2), 2004, pp. 405–407 ᭧ American Society of Parasitologists 2004 Infection by Anisakid Nematodes Contracaecum spp. in the Mayan Cichlid Fish
‘Cichlasoma (Nandopsis)’ urophthalmus (Gu
¨ nther 1862)
Gaddy T. Bergmann and Philip J. Motta, Department of Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa,
Florida 33620. e-mail: gaddyfl25@yahoo.com
Larval nematodes that parasitize the Mayan cichlid fish fection by Contracaecum spp. in ‘C. (Nandopsis)’ urophthalmus differs ‘Cichlasoma (Nandopsis)’ urophthalmus (Gu¨nther 1862) in southern among habitats or through ontogeny. Because Contracaecum spp. par- Florida were identified as Contracaecum spp. (Nematoda: Anisakidae, asitize both marine and freshwater fishes, it was hypothesized that nei- Anisakinae). The objective of this study was to determine whether in- ther prevalence nor infection intensity of the nematodes would differ fection intensity and prevalence of these parasites differ between a significantly between adult ‘C. (Nandopsis)’ urophthalmus from a brackish water and freshwater habitat or through ontogeny in the fresh- brackish water site (BWS) and a freshwater site (FWS). Finally, on the water habitat only. The nematodes were removed from the abdominal basis of the notion that Contracaecum spp. might accumulate in ‘C. cavity of the fishes and counted. Infection intensity was compared be- (Nandopsis)’ urophthalmus with time, it was hypothesized that both tween habitats using analysis of covariance and evaluated through on- prevalence and infection intensity would increase significantly through togeny using Spearman rank order correlation. Prevalence was com- ontogeny at the FWS where juvenile fishes were collected.
pared between habitats and between adults and juveniles from the fresh- The 2 sites chosen for this study, one of which is a brackish water water habitat using a z-test. Although infection intensity did not differ habitat and the other a freshwater, are part of the canal system of south- between habitats, infection prevalence was greater at the freshwater site ern Florida. The first site was located approximately at the intersection (FWS). Both the prevalence and intensity of nematode infection in- of US-41, the Tamiami Trail, and State Route 29. This is the site of creased through ontogeny at the FWS, and no nematode was found in intersection of the Tamiami Canal and the Main Barron River Canal in fishes that were smaller than 93 mm standard length. Thus, the parasites Carnestown, Collier County (25Њ54Ј41ЉN,81Њ21Ј53ЉW), at the western appear to accumulate during the lifetime of the fishes.
border of the Big Cypress National Preserve. This region of the Tam-iami Canal passes through brackish water and consists mostly of saltmarsh and some mangrove stands and naturally experiences seasonal Native to the Atlantic slope of tropical Central America (Miller, saltwater influx from Chocoloskee Bay. Data from a nearby water mon- 1966), the Mayan cichlid ‘Cichlasoma (Nandopsis)’ urophthalmus itoring station on the Tamiami Canal (25Њ57Ј40ЉN,81Њ30Ј60ЉW) are used (Gu¨nther 1862) was first recorded in Florida in 1983 from the Ever- in this study as indicators of the salinity fluctuations at this first collec- glades National Park (Loftus, 1987). It is referred to in this study as tion site. In this region, salinity fluctuates seasonally from 0.00 to 34.30 ‘C. (Nandopsis)’ urophthalmus in accord with the convention for tax- ppt. Sampling at this site took place on 29 April 2000 and 27 May onomically undetermined cichlids (Stiassny, 1991). The means by 2000. The second collection site was within the Big Cypress National which ‘C. (Nandopsis)’ urophthalmus was introduced into Florida are Preserve in the canal along State Route 94 (Loop Road), east of Trail unknown (Loftus, 1987), but it is likely that it was released by private City, Monroe County (25Њ45Ј35ЉN,81Њ0Ј9ЉW). This area is a freshwater aquarists. This species is euryhaline and can survive in a range of sa- cypress swamp, and sampling took place on a monthly basis from 24 linity from 0 to 40 ppt (Martinez-Palacios and Ross, 1992; Martinez- June 2000 to 19 October 2000. Data from a nearby water monitoring Palacios et al., 1993). ‘Cichlasoma (Nandopsis)’ urophthalmus is sus- station on the Tamiami Canal (25Њ50Ј35ЉN,80Њ55Ј4ЉW) verify that this ceptible to infection by parasites such as nematodes (roundworms), di- is a FWS, with salinity ranging from 0.00 to 0.29 ppt only.
genean trematodes, and poecilostomatoid copepods (Vidal-Martı´nez et Fishes were collected from the BWS and the FWS using seine and al., 1994; Salgado-Maldonado and Kennedy, 1997). In the present study, dip nets, hook and line angling, and minnow traps. Samples were ‘C. (Nandopsis)’ urophthalmus was found to have larval Contracaecum taken on a monthly basis from 29 April 2000 to 19 October 2000 to spp. (Nematoda: Anisakidae, Anisakinae) (E. C. Greiner, pers. comm.) minimize the confounding effect of changing seasons; 257 ‘C. (Nan- in the coelom. The species of Contracaecum infects ‘C. (Nandopsis)’ dopsis)’ urophthalmus were collected for this study. Fifty-three urophthalmus in Mexico (Vidal-Martı´nez et al., 1994; Salgado-Maldon- adults were collected from the brackish water population. Sixty-eight ado and Kennedy, 1997). Lament (1999) found parasitic nematodes in adults and 136 juveniles were collected from the freshwater popu- the visceral cavity of ‘C. (Nandopsis)’ urophthalmus collected in the lation. Only adult ‘C. (Nandopsis)’ urophthalmus were considered Everglades region but did not identify them. The nematode described when comparing the brackish and freshwater habitats. All individ- in Lament (1999) may also be Contracaecum spp.
uals greater than 102 mm standard length (SL) were considered to Contracaecum spp. are widely distributed parasitic nematodes. Be- be adults (Caso Cha´vez et al., 1986; Martinez-Palacios and Ross, sides ‘C. (Nandopsis)’ urophthalmus, they have also been recovered 1992; Martinez-Palacios et al., 1993; Faunce and Lorenz, 2000). It from other cichlids and many other fishes and aquatic birds (Deardorff was presumed that the 2 groups sampled are not subpopulations ca- and Overstreet, 1980; Banks and Ashley, 2000; Machado et al., 2000).
pable of intermixing because ‘C. (Nandopsis)’ urophthalmus is phil- Anisakids, such as Contracaecum spp., usually infect the alimentary opatric or site tenacious (Caso Cha´vez et al., 1986; Salgado-Mal- tract of their definitive hosts, which are generally marine mammals.
donado and Kennedy, 1997; Faunce and Lorenz, 2000).
Marine crustaceans, cephalopod mollusks, or fishes often serve as in- Fishes were killed with an overdose of tricaine methanesulfonate termediate or paratenic (transport) hosts. Anisakids are not found in the (MS-222). They were then injected with 10% buffered formalin and flesh of fishes, they infect the visceral organs instead. Thus, these par- placed on ice for preservation. On return to the laboratory, the fishes asites are not usually harmful to the fish they infect (Deardorff and were cut from vent to pelvic girdle. All parasitic nematodes found in Overstreet, 1980; Bush et al., 2001). In experimental infections of ju- the coelomic cavity were removed and counted. The parasites were then venile and adult chickens, mallard ducklings, mice, hamsters, and rats, fixed in 10% buffered formalin and stored in 70% ethanol. Twelve Contracaecum multipapillatum was not harmful. However, in marine nematodes from both the brackish and freshwater populations were birds, C. multipapillatum can infect the proventriculus portion of the identified by E. C. Greiner, Department of Pathobiology, College of stomach and cause lesions. This parasite can also cause granuloma in Veterinary Medicine, University of Florida, Gainesville, Florida. The dogs that eat fish. Contracaecum multipapillatum is also capable of fact that only 1 site was used for each habitat type means that there is infecting domestic cats (Deardorff and Overstreet, 1980; Vidal-Martı´nez no replication for each treatment. Therefore, statistical power is low, et al., 1994). Anisakids are dangerous when ingested by humans, caus- and the results of the analysis presented in this study must be interpreted ing a condition known as anisakiasis, which causes violent abdominal with caution. Parasite infection was quantified using both prevalence pain, nausea, and vomiting (Bush et al., 2001; Plath et al., 2001).
(the proportion of the host population infected) and intensity (the num- The goal of this study was to determine whether the pattern of in- ber of parasites per host). Descriptive statistics were computed using THE JOURNAL OF PARASITOLOGY, VOL. 90, NO. 2, APRIL 2004 the arithmetic mean as the measure of central tendency and the standard dopsis)’ urophthalmus is also detritivorous (Caso Cha´vez et al., 1986; deviation as the measure of data dispersion. Because nematodes are Martinez-Palacios and Ross, 1988; Bergmann, 2002). In the detritivo- individual organisms, descriptive statistics are reported in this study rous striped mullet, Mugil cephalus, fish size is likewise positively cor- using whole numbers. Prevalence was compared between sites and be- related with the intensity of infection by Contracaecum spp. and other tween adults and juveniles at FWS using a z-test with an alpha level of parasites combined (Valles-Rios et al., 2000). Thus, detritivory may lead 0.05. Comparison of infection intensity between sites was accomplished to an increase in infection intensity through ontogeny, perhaps because using analysis of covariance (ANCOVA), with SL as covariate and an of repeated exposure to the parasite. Further investigation would be alpha value of 0.05. Both the number of nematodes and the SL were necessary to determine whether predation, detritivory, or other factors square-root transformed for analysis. Infection intensity was examined are the primary sources of infection by Contracaecum spp. in ‘C. (Nan- through ontogeny at FWS using Spearman rank order correlation on dopsis)’ urophthalmus.
untransformed data (Zar, 1996). The statistical programs used were The Department of Biology at the University of South Florida pro- SigmaStat 2.03 and SYSTAT 10.0 (SPSS Science).
vided generous support. We thank S. S. Bell, E. D. McCoy, W. F. Font, Contracaecum spp. found in the visceral cavity of ‘C. (Nandopsis)’ and anonymous reviewers for their contributions to this publication. We urophthalmus ranged from approximately 5 to 20 mm in length. They are grateful to E. C. Greiner for identifying the parasitic nematodes were less than 1 mm in cross-sectional diameter, light pink in color, and found within the Mayan cichlids. We also thank S. Connor, J. Hill, S.
generally found in a coiled position, although some were extended.
Huskey, J. Lament, B. Loftus, and K. O. Winemiller for their guidance.
These larvae were probably all in the L3 stage (B. G. Chitwood and We are grateful to K. Dugan of Collier County for providing us with M. B. Chitwood, 1974; E. R. Noble and G. A. Noble, 1982; Olsen, water quality data. Finally, we acknowledge A. Cockburn, S. Jacobson, 1986), and only these larvae were considered in this analysis. Of the D. Klemm, J. Krebs, H. Porter, and M. Robeson for their critical tech- 56 fish collected from BWS, 22 contained Contracaecum spp. (none nical assistance. The contents of this paper are from a thesis submitted among the 3 juvenile specimens, and all 22 among the 53 adults). This to the University of South Florida by G.T.B. in partial fulfillment of the is equivalent to 39.3% of all BWS fish sampled or 41.5% of the adults.
requirements for an M.S. degree in zoology. This research was con- Of the 204 fishes collected at FWS, 47 were infected with the nema- ducted with approval by the University of South Florida Institutional todes (3 among the 136 juveniles and 44 among the 68 adults). This is Animal Care and Use Committee, file 1714.
equivalent to 23.0% of all FWS fishes or 2.2% of juveniles and 64.7%of adults. The z-tests revealed that prevalence of infection was signifi-cantly higher in FWS adults than in either BWS adults (z ϭ 2.359, P LITERATURE CITED
ϭ 0.018) or FWS juveniles (z ϭ 9.850, P Ͻ 0.001).
Infection intensity per individual fish at BWS ranged from 1 to 16 ANKS, S. M., AND D. C. ASHLEY. 2000. Observations on the internal helminth parasite fauna of largemouth bass, Micropterus salmoides, nematodes, whereas it ranged from 1 to 43 nematodes at FWS. If the from Smithville Reservoir, Missouri. Journal of Freshwater Ecol- individual fish that contained 43 nematodes is discarded from the anal- ogy 15: 299–306.
ysis, infection intensity at FWS ranged from 1 to 6 nematodes. Meaninfection intensity among adults at BWS was 2 Ϯ 4 worms/fish. At BERGMANN, G. T. 2002. Trophic ecomorphology of the nonindigenous FWS, mean infection intensity was 2 Ϯ 5 worms/fish for adults and 0 Mayan cichlid ‘Cichlasoma (Nandopsis)’ uropthalmus (Gu¨nther, Ϯ 0 worms/fish for juveniles. ANCOVA indicates that infection inten- 1862) in southern Florida. M.S. Thesis. University of South Flor- sity is not significantly different between sites (F ϭ 2.621, P ϭ 0.108).
Nematode infection showed an increase through ontogeny at FWS.
BUSH, A. O., J. C. FERNA´NDEZ, G. W. ESCH, AND J. R. SEED. 2001.
Very small fish showed no evidence of infection. Ninety-three milli- Parasitism: The diversity and ecology of animal parasites. Cam- meters was the first SL at which infection was recorded. Beyond this bridge University Press, New York, 566 p.
length, there was no clear relationship between SL and infection inten- CASO CHA´VEZ, M., A. YA´N˜EZ-ARANCIBIA, AND A. L. LARA-DOMı´NGUEZ.
sity as the fish continued to grow. A Spearman rank order correlation 1986. Biologia, ecologia y dinamica de poblaciones de Cichlasoma was performed to evaluate Contracaecum spp. infection through ontog- urophthalmus (Gunter) (Pisces: Cichlidae) en habitat de Thalassia eny. Two separate tests were performed, 1 including the outlying data testudinum y Rhizophora mangle, Laguna de Terminos, sur del Gol- point of 43 nematodes in the coelom of 1 fish and 1 excluding that data fo de Mexico. Biotica 11: 79–111.
point. If the outlier was included, there was a significant and positive CHITWOOD, B. G., AND M. B. CHITWOOD. 1974. Introduction to Nema- correlation between number of nematodes in the coelom and SL (R2 ϭ tology. University Park Press, Baltimore, Maryland, 334 p.
0.612, P Ͻ 0.001). If the outlier was excluded, a similar result was DEARDORFF, T. L., AND R. M. OVERSTREET. 1980. Contracaecum mul- obtained (R2 ϭ 0.605, P Ͻ 0.001).
tipapillatum (ϭC. robustum) from fishes and birds in the northern The broad ranges of Contracaecum spp. appear to be naturally oc- Gulf of Mexico. Journal of Parasitology 66: 853–856.
curring, probably because of migratory birds (Deardorff and Overstreet, FAUNCE, C. H., AND J. J. LORENZ. 2000. Reproductive biology of the 1980). It is presently unclear whether ‘C. (Nandopsis)’ urophthalmus introduced Mayan cichlid, Cichlasoma urophthalmus, within an es- in Florida are infected by a Contracaecum spp. from Florida, from tuarine mangrove habitat of southern Florida. Environmental Bi- Central America, or by species from both locations (Hoffman and Schu- ology of Fishes 58: 215–225.
bert, 1984; Lament, 1999). This study shows that although infection HOFFMAN, G. L., AND G. SCHUBERT. 1984. Some parasites of exotic intensity among adults did not differ significantly between sites, adults fishes. In Distribution, biology, and management of exotic fishes, at FWS exhibited a significantly higher prevalence of infection by Con- W. R. Courtenay Jr. and J. R. Stauffer Jr. (eds.). The Johns Hopkins tracaecum spp. than adults at BWS. The cause for this higher preva- University Press, Baltimore, Maryland, p. 233–261.
lence of infection at FWS could be attributed to a greater density of LAMENT, J. J. 1999. Life history variation in introduced populations of the fishes at this site, but this remains to be determined. This study also Mayan cichlid, Cichlasoma urophthalmus in the Everglades. Ph.D.
shows that smaller ‘C. (Nandopsis)’ urophthalmus harbors fewer para- Dissertation, University of Miami, Coral Gables, Florida, 153 p.
sites than do larger individuals. The smallest infected fish from BWS LOFTUS, W. F. 1987. Possible establishment of the Mayan cichlid, Cich- was 115 mm SL, and the smallest infected fish from FWS was 93 mm lasoma urophthalmus (Gu¨nther) (Pisces: Cichlidae), in Everglades SL. However, there is no clear relationship between size and infection National Park, Florida. Florida Scientist 50: 1–6.
intensity beyond the minimum age of infection.
MACHADO, P. M., S. C. DE ALMEIDA, G. C. PAVANELLI, AND R. M. TAK- Larger individuals may harbor more parasites because they have had EMTO. 2000. Ecological aspects of endohelminths parasitizing Cich- more time to accumulate them. ‘Cichlasoma (Nandopsis)’ urophthalmus la monoculus Spix, 1831 (Perciformes: Cichlidae) in the Parana are carnivorous, feeding on decapod crustaceans such as crayfish Pro- River near Porto Rico, State of Parana, Brazil. Comparative Para- cambarus sp. and shrimp Palaemonetes paludosus. They also prey on sitology 67: 210–217.
fish such as mosquitofish Gambusia holbrooki, sailfin mollies Poecilia MARTINEZ-PALACIOS, C. A., C. CHAVEZ-SANCHEZ, AND M. A. OLVERA latipinna, and juvenile ‘C. (Nandopsis)’ urophthalmus (Caso Cha´vez et NOVOA. 1993. The potential for culture of the American Cichlidae al., 1986; Martinez-Palacios and Ross, 1988; Bergmann, 2002). Con- with emphasis on Cichlasoma urophthalmus. Recent Advances in suming these prey items could have led to postcyclic parasitic trans- Aquaculture 4: 193–232.
mission (Scott, 1954; Smith and Wootten, 1975). However, ‘C. (Nan- ———, AND L. G. ROSS. 1988. The feeding ecology of the Central American cichlid Cichlasoma urophthalmus (Gunther). Journal of of the marine nematode from smelt. Journal of the Fisheries Re- Fish Biology 33: 665–670.
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J. Parasitol., 90(2), 2004, pp. 407–409 ᭧ American Society of Parasitologists 2004 Ex Vivo Anthelmintic Activity of Albendazole-Sulphoxide Enantiomers
F. Bola´s-Ferna´ndez, S. Rama-In
˜ iguez, and J. J. Torrado*, Departamento de Parasitologı´a, Facultad de Farmacia, Universidad Complutense,
28040 Madrid, Spain; *Deparmento de Farmacia y Tecnologı´a Farmace´utica, Facultad de Farmacia, Universidad Complutense, 28040 Madrid,Spain. e-mail: francisb@farm.ucm.es The antiparasitic activity of racemic albendazole-sulphox- macokinetic behavior of ABZSO enantiomers have been documented ide (Ricobendazole ϭ racRBZ) and its (ϩ) and (Ϫ) enantiomers was in sheep (Capece et al., 2000). Furthermore, the selective uptake of tested in an ex vivo murine model for Trichinella spiralis infection.
ABZSO enantiomers and their selective binding to cytosolic proteins Larvae were isolated from the muscle of infected mice and exposed to isolated from different helminth parasites has also been demonstrated concentrations between 0.01 and 1 ␮g/ml of the racemic mixture or to (Alvarez et al., 2000; Solana et al., 2002). Thus, these factors must be each of its enantiomers. The activity of each compound was then as- taken into account because they may contribute significantly to the phar- sayed by measuring the ability of the treated larvae to infect naive mice macological properties of this chiral molecule.
(larval viability). At a concentration of 0.5 ␮g/ml, all 3 compounds were However, despite the interest in these agents, the antiparasitic activity highly effective in reducing the viability of the larvae, achieving re- of the (ϩ)ABZSO and (Ϫ)ABZSO enantiomers has never been directly ductions of 91.26% (racRBZ), 96.7% (ϩ), and 89.2% (Ϫ), when com- tested. Using optimized chiral high-performance liquid chromatography pared with untreated controls. At lower concentrations (0.1 ␮g/ml), only (HPLC), we have been able to obtain very pure samples of (ϩ)ABZSO treatment with (ϩ)RBZ rendered a significant reduction in larval via- and (Ϫ)ABZSO. This has enabled us to test the anthelmintic activity of bility in comparison with controls (84.3%; P Ͻ 0.01), whereas at 0.01 these enantiomers in an ex vivo model system, using the well-estab- ␮g/ml, none of the compounds altered larval viability (P Ͼ 0.05).
lished murine model of Trichinella spiralis infection.
To purify ricobendazole enantiomers from a racemic ABZSO mixture Albendazole (ABZ), methyl (5-(propyl-thio)-1-H-benzimidazole-2yl) (Ricobendazole ϭ RBZ), a modular liquid chromatography apparatus carbamate, is a broad-spectrum drug that acts against the most important was used, equipped with: a Jasco PU-1580 isocratic pump (Tokyo, Ja- animal and human helminth parasite species (Horton, 2000). After ad- pan); an automatic sampler (Gilson 231 XL, Villers le Bels, France) ministration, ABZ is rapidly transformed by 2 distinct hepatic micro- fitted to a 100-␮l sampler loop (Rheodyne, Rohnert Park, California); somal enzyme systems: the flavin-containing monooxygenase system a variable wavelength detector (UV-1575, Jasco); and a PC integrator (Lanusse et al., 1993) and the cytochrome P-450 chain (Souhaili-El (Borwin 1.5, JMBS developments [Jasco]). Before injection, the sam- Amri et al., 1987). These modifications produce albendazole-sulphoxide ples were filtered through a polyvinylidene fluoride Durapore௡ 0.45-␮m (ABZSO) and albendazole-sulphone, the main metabolites that can be filter (Millipore Co., Boston, Massachusetts). Subsequently, the racemic recovered from the plasma of sheep (Lanusse et al., 1995), cattle (San- ricobendazole (racRBZ) sample mix was injected into the HPLC system chez et al., 1997), mice (Rueda-Polo et al., 1998), and humans (Pro- at a concentration of 0.1 mg/ml, and chiral HPLC separation was per- chanzkova et al., 2000). Because of their affinity for the parasite’s beta- formed according to a modified version of the method described pre- tubulin, both ABZ and ABZSO exhibit antiparasitic activity (Lacey, viously by Delatour et al. (1990) (Garcia et al., 1999). Briefly, a chiral– 1988). However, ABZ can be further metabolized and is thus only found alpha 1-acid glycoprotein column (100 ϫ 4 mm, 5 ␮m) and a mobile at low levels in plasma. Hence, the ABZSO product is thought to be phase containing sodium phosphate buffer (8 mM, pH 7.0), at a flow the more active of the 2 in combating tissue-dwelling parasites (Mar- rate of 0.9 ml/min, were used. The samples were analyzed at 290 nm, riner and Bogan, 1980). The chiral core in the sulfur atom of ABZSO and under these conditions, the retention times for (Ϫ) and (ϩ)RBZ permits 2 enantiomers to be generated, (ϩ)ABZSO and (Ϫ)ABZSO.
were 3.1 and 10.5 min, respectively. The liquid samples were collected The pharmacokinetic disposition of ABZSO enantiomers after oral ad- in accordance with the retention times of the enantiomers. The samples ministration of ABZ in distinct animal species and humans (Delatour, were concentrated to dryness under vacuum at 70 C using a Savant Benoit et al., 1991; Delatour, Garnier et al., 1991; Garcia et al., 1999) Speedvac௡ concentrator (Holbrook, New York). The samples recovered reveals differences that possibly reflect the selective metabolism of ABZ were quantified by the same HPLC method described above but in- and ABZSO enantiomers (Marques et al., 1999; Solana et al., 2000; cluded 2-propanol (1 ml/L) as an additive in the mobile phase. Under Virkel et al., 2002). Indeed, even sex-related differences in the phar- these conditions, the retention times after injection were 2.6 min for

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