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Austrodiplostomum compactum (Lutz, 1928) (Digenea, Diplostomidae) in the eyes of fishes from Parana river, Brazil/Austrodiplostomum compactum (Lutz, 1928) (Digenea, Diplostomidae) em olhos de peixes do rio Parana, Brasil.

Introduction

Metacercariae of Diplostomum and Austrodiplostomum are frequently reported parasitizing freshwater fishes which are the second intermediate hosts in the parasite's life-cycle (RINTAMAKI-KINNUNEN et al., 2004; SEPPALA et al., 2004). Whereas the adult stage inhabits the digestive tract of piscivore birds, its larval cercariae stage may be found in aquatic mollusks. The parasite has a geographically wide range with reports from over 125 fish species (EIRAS, 1994).

There are several reports from Brazil on diplostomid metacercariae parasitizing fishes. Metacercariae have been found in Plagioscion squamosissimus Heckel, 1840 (KOHN et al., 1995; MACHADO et al., 2005; MARTINS et al., 2002; PAES et al., 2003, 2010; SANTOS et al., 2002; TAKEMOTO et al., 2009), Hypostomus regani Ihering, 1905 (TAKEMOTO et al., 2009; YAMADA et al., 2008; ZICA et al., 2009), Cichla monoculus Spix and Agassiz, 1831 (MACHADO et al., 2000, 2005; TAKEMOTO et al., 2009), Cichla ocellaris Bloch and Schneider, 1801 (MACHADO et al., 2005; SANTOS et al., 2002), Pimelodus maculatus Lacepede, 1803 (BRASIL-SATO; PAVANELLI, 2004; BACHMANN et al., 2007), Hoplias malabaricus Bloch, 1794 (MACHADO et al., 2005; TAKEMOTO et al., 2009), Satanoperca pappaterra Heckel, 1840 (MACHADO et al., 2005; TAKEMOTO et al., 2009), Geophagus brasiliensis Quoy and Gaimard, 1824 (AZEVEDO et al., 2006; NOVAES et al., 2006) and Crenicichla britskii Kullander, 1982 (MACHADO et al., 2005; TAKEMOTO et al., 2009), Serrasalmus maculatus Kner, 1858, Schizodon borellii Boulenger, 1900 and Auchenipterus osteomystax Mirando Ribeiro, 1918 (TAKEMOTO et al., 2009; YAMADA et al., 2008), Conorhynchos conirostris Valenciennes, 1840 (BRASIL-SATO; SANTOS, 2005), Cyphocharax Gilbert Quoy and Gaimard, 1824 (ABDALLAH et al., 2005) and Cichlasoma paranaense Kullander, 1983 (MACHADO et al., 2005; TAKEMOTO et al., 2009).

The River Parana is the second largest river in extension in South America and commercial fishing is one of its important local economic activities. Kohn et al. (1995), Santos et al. (2002), Brasil-Sato and Pavanelli (2004), Machado et al. (2005) and Yamada et al. (2008) have registered parasitosis by A. compactum in fishes from the Parana river basin.

Current research reports on the occurrence of Austrodiplostomum compactum (Lutz, 1928) in four fish species from the Parana river, as well as its ecological aspects with regard to parasitological indexes, rainfall and water quality.

Material and methods

Current research was undertaken at the Aquaculture Center of the Universidade do Oeste Paulista (UNOESTE), on the shores of the Parana river, near the town of Presidente Epitacio, state of Sao Paulo (21[degrees] 45' 48" S; 52[degrees] 06' 56" W). Fifty-one specimens of P. squamosissimus, 39 G. surinamensis, 27 H. malabaricus and 23 Cichla sp. were collected with gill nets and hooks, between June 2007 and June 2008, comprising

the winter of 2007 thru the winter of 2008, for parasitological exam undertaken according to Santos et al. (2002). Geophagus surinamensis, H. malabaricus and Cichla sp. were not captured during the summer of 2007. Parasite specimens were fixed in 5% formaldehyde, washed in distilled water, stained in carmine or diaphanized in beechwood creosote and mounted on permanent slides using Canada balsam. The terms prevalence, mean intensity of infection and mean parasite abundance were attributed according to Bush et al. (1997).

The water quality was monthly measured. Water temperature and dissolved oxygen were measured with digital oxymeter YSI 5512; ammonia, pH, and alkalinity were calculated with Merk's colorimetric method. Rainfall indexes were obtained from the meteorological station of the Universidade do Oeste Paulista (UNOESTE) in Presidente Prudente, Sao Paulo State, Brazil.

Collected data underwent statistical tests to compare rainfall, air temperature and water quality between seasons; to determine differences between the intensity of infection and abundance of parasites in fish between the seasons; to verify which fish species was more parasitized during the whole period and the possible differences in host weight and length for each fish species examined according to season. ANOVA and Bartlett's test for variance homogeneity were used, with significance for all statistical analyses set at [alpha] = 0.05.

Results and discussion

No significant differences in rainfall indexes between seasons were observed. However, temperature rates were high (p < 0.05) in the spring and summer 2007. The highest water temperatures (p < 0.05) occurred in the spring 2007, summer 2007 and autumn 2008. High alkalinity rates were reported in the winter and spring 2007 and autumn 2008, but no difference in pH and dissolved oxygen occurred during the seasons (Table 1).

Mean highest rainfall during the studied period occurred in the winter 2007, spring 2007 and autumn 2008. Oscillations occurred in water alkalinity and pH during the period under analysis. The highest temperature rates were registered between spring 2007 and autumn 2008, although there were considerable variations in all months. Dissolved oxygen levels also varied during the year (Table 1).

Metacercariae at different stages of development were collected from the crystalline of host's eyes in all fish species.

Except for autumn 2008, the prevalence of A. compactum in P. squamosissimus was 100%, even though the highest parasite numbers were observed in autumn 2008 (255) and spring 2007 (222) (Table 2). The mean highest infection intensities were reported in spring 2007 (45.0 [+ or -] 65.8) and in autumn 2008 (59.3 [+ or -] 70.0) (Table 2).

Parasites from G. surinamensis were reported only between autumn and winter 2008. Although no fish was collected in the summer 2008, mean infection intensities were low, varying between 12 and 18.2 parasites, and mean abundance varying between 10.4 and 18.2 (Table 3).

Prevalence of H. malabaricus varied from 46.6 to 83.3% between winter 2007 and autumn 2008 (Table 4). The highest number of parasites was registered in winter 2007 (247) with mean infection intensity (35.2 [+ or -] 18.2) and mean abundance (16.4), followed by winter 2008, with total number of parasites 214, mean intensity 71.3 [+ or -] 97.6 and abundance 53.5 (Table 4).

Metacercariae prevalence in Cichla sp. varied between 23 and 100%, with the mean lowest infection intensities (1.3 to 8.5 parasites). Therefore, mean abundance values varied from 0.3 to 7.1, with the highest number of parasites in the autumn 2008 (50) (Table 5).

Regardless of fish species, no significant difference (p > 0.05) between the seasons was reported in parasitological indexes. Contrastingly, when each fish species was analyzed regardless of the season, P. squamosissimus was found to be the most parasitized fish (p < 0.05).

No significant difference (p > 0.05) occurred between host weight and total length for all fish species between the seasons.

Santos et al. (2002) registered a positive relationship between mean infection intensity and rainfall, associated with high temperatures. Current study agrees with previous one in which all fish species were reported with the highest infection intensity during the months with the mean highest rainfall and which coincided with the highest temperatures.

In contrast, analyzing P. squamosissimus from Nova Avanhandava reservoir in the state of Sao Paulo, Brazil, Paes et al. (2010) did not report any influence either of aquatic parameters or of rainfall on the parasitic fauna. Since transmission is a major determinant of parasite fitness, perhaps other factors, such as local host population dynamics, fish feeding habits, strategies in cercarial release from first intermediate hosts and also the type of fresh water environments (lotic or lentic environment), would be primarily influencing success in parasite transmission.

There is a wide range of fish species collected from Brazil which are parasitized by metacercariae of A. compactum. Fifty percent of these fish species, namely, A. osteomystax, C. monoculus, C. ocellaris, S. pappaterra, H. malabaricus and P. squamosissimus, registered over 50% prevalence rates. The latter species achieved indexes up to 100% (Table 6). Plagioscion squamosissimus, also with mean high infection intensity, was the most parasitized fish species reported not only in current study but also in Santos et al. (2002), Martins et al. (2002) and Paes et al. (2010). Santos et al. (2002) reported the highest parasitological indexes in March 2001 for fish species, with infection intensities ranging from 4 to 137 parasites per host eye, while Martins et al. (2002) reported the highest infection intensities during late winter 2000 and late summer 2001. Although no significant difference in mean intensity and abundance of metacercariae throughout the seasons has been reported in current research, P. squamosissimus examined in spring and autumn had the highest parasitic load when compared to findings by Paes et al. (2010) in the same fish species in the Nova Avanhandava reservoir.

According to Lyholt and Buchmann (1996) and Hakalahti et al. (2006), infection of fishes by Diplostomum spathaceum (Rudolphi, 1819) metacercariae is temperature dependent. Hoglund and Thulin (1990) observed in their study that the maximum temperature (up to 23[degrees]C) coincided with the period of reduced recruitment of Diplostomum baeri Dubois 1937 metacercariae in perch Perca fluviatilis Linnaeus 1758. The highest prevalence and mean intensity observed in this study for P. squamosissimus, G. surinamensis and H. malabaricus were registered at water temperatures between 21.4 and 29.0[degrees]C. Such data may be explained by data from Hakalahti et al. (2006), according to whom extended summer temperatures would alter the dynamic population of cercariae and consequently the fish infection by metacercariae.

Due to the fact that water temperature at the collection site analyzed in current research was higher than that in Hakalahti et al. (2006), infection behavior at low temperatures cannot be evaluated. Martins et al. (2002) registered the positive influence of high temperatures on A. compactum infection in P. squamosissimus. In fact, their suggestion may be confirmed in current study for P. squamosissimus, a fish collected during the whole period under analysis. According to Berrie (1960), Diplostomum cercariae emerge in waters only at temperatures above 10[degrees]C. Lyholt and Buchmann (1996) registered that daily shedding of D. spathaceum cercariae in Lymnaea stagnalis (Linnaeus, 1758) reached a maximum of 58,000 cercariae [snail.sup.-1] [day.sup.-1] at 20[degrees]C and a maximum of 10,000 cercariae [snail.sup.-1] [day.sup.-1] at 10[degrees]C. These authors also concluded that cercariae were 4 to 5 times more infective at 15[degrees]C than at 7[degrees]C, reinforcing the impact of temperature on the parasite's life-cycle. Although adaptations in temperature margins would be expected to suit local conditions, it seems that parasite biology is dependent on high temperatures, as suggested by Santos et al. (2002), Martins et al. (2002) and Hakalahti et al. (2006).

Luque and Poulin (2004) compared 50 teleost fish species from the coast of Brazil to evaluate the effects of host traits on the richness and abundance of larval helminths and reported that among all the potential correlates, host body length was positively correlated with helminth larvae abundance. Machado et al. (2005) registered a positive correlation between C. britskii size and the prevalence of A. compactum and attributed this fact to the possibility of larger fish being easier targets for cercariae. The parasite load in P. squamosissimus increased with fish length, as reported by Paes et al. (2010). These authors also attributed the cumulative process to a greater body surface available for cercariae infection. According to Pojmanska (1994), there is evidence on the positive correlation between parasite number and fish size, arguing that accumulation is due to the metacercariae's long life. On the other hand, Valtonen and Gibson (1997) concluded that the diplostomid metacercariae infection in fishes from northern Finland provided little or no association between the prevalence of infection and host-size, even though there was a distinct accumulation in the number of parasites.

With regard to the above, Burrough (1978), analyzing the population biology of D. spathaceum in roach Rutilus rutilus and rudd Scardinius erythrophthalmus, concluded that parasite accumulation occurred up to the time fish reached 130 mm. Unfortunately, it was not possible to compare our results with those of the latter author due to the lack of analyzed fishes measuring less than 130 mm. This fact did not depend on fishing tactics since the animals were captured with hook and net, similar to that for collection species. No distinct accumulation was reported and thereafter intensity ranged between all levels.

The Brazilian records for diplostomid metacercariae parasitosis show different sites of parasite infection in the host's body, despite an apparent preference for the fish's eyes, including aqueous humor and crystalline (Table 6). Amato et al. (2001) recorded an unidentified Diplostomidae from kidney, body cavity, mesentery and brain of Loricariichthys anus (Valenciennes, 1835), whereas Brasil-Sato and Santos (2005) registered A. compactum (D. compactum) in the gills and eyes of C. conirostris (Table 6). According to Eiras (1994), reports by several authors suggest that Diplostomum species have their own location preferences. Bortz et al. (1988) verified that parasites collected from the hosts' retina and crystalline corresponded to populations with different epidemiological characteristics and thus different parasite species. Alternatively, the parasite infection site may be related to fish species. Whatever the mechanisms involved in parasite's preferences, more studies identifying correctly the parasite location and also a revision of the group systematics are necessary to elucidate this question. The taxonomy, especially regarding larval stages, is still unclear and several species, considered adults in nature, have never actually been observed as larvae and vice-versa (HOGLUND; THULIN, 1990).

Conclusion

Hoglund and Thulin (1990) state that fishes harboring more than 40 diplostomid metacercariae on their eyes are largely parasitized. In the present study, P. squamosissimus and H. malabaricus may therefore be considered the main host resources used by the parasite within the context of the river under analysis. It may be concluded that these fish species may not only be the most susceptible fish species but also good indicators of Austrodiplostomum infection.

Doi: 10.4025/actascibiolsci.v34i2.9337

Acknowledgements

The authors thank CNPq (National Council of Scientific and Technological Development) for Grant to M.L. Martins and CAPES (Coordination of Improvement of Higher Education Personnel) for scholarship to N.C. Marchiori.

References

ABDALLAH, V. D.; AZEVEDO, R. K.; LUQUE, J. L. Ecologia da comunidade de metazoarios parasitos do sairu Cyphocharax gilbert (Quoy and Gaimard, 1824) (Characiformes: Curimatidae) do rio Guandu, Estado do Rio de Janeiro, Brasil. Revista Brasileira de Parasitologia Veterinaria, v. 14, n. 4, p. 154-159, 2005.

AMATO, S. B.; AMATO, J. F. R.; ALBRECHT, M. Metacercarias livres de diplostomideos (Digenea, Diplostomidae) em Loricariichthys anus (Val., 1840) (Siluriformes, Loricariidae) do Estado do Rio Grande do Sul, Brasil. Parasitologia al Dia, v. 25, n. 1-2, p. 24-29, 2001.

AZEVEDO, R. K.; ABDALLAH, V. D.; LUQUE, J. L. Ecologia da comunidade de metazoarios parasitos do acara Geophagus brasiliensis (Quoy & Gaimard, 1824) (Perciformes: Cichlidae) do Rio Guandu, Estado do Rio de Janeiro, Brasil. Acta Scientiarum. Biological Sciences, v. 28, n. 4, p. 403-411, 2006.

BACHMANN, F.; GREINERT, J. A.; BERTELLI, P. W.; SILVA FILHO, H. H.; LARA, N. O. T.; GHIRALDELLI, L.; MARTINS, M. L. Parasitofauna de Pimelodus maculatus (Osteichthyes: Pimelodidae) do rio Itajai-acu em Blumenau, Estado de Santa Catarina, Brasil. Acta Scientiarum. Biological Sciences, v. 29, n. 1, p. 109-114, 2007.

BERRIE, A. D. Two Diplostomulum larvae (Strigeida, Trematoda) in the eyes of sticklebacks (Gasterosteus aculeatus L.). Journal of Helminthology, v. 34, n. 21, p. 211-216, 1960.

BORTZ, B. M.; KENNY, G. E.; PAULEY, G. B.; BUNT-MILAM, A. H. Prevalence of two site-specific populations of Diplostomum spp. in eye infections of rainbow trout, Salmo gairdneri Richardson, from lakes in Washington State, USA. Journal of Fish Biology, v. 33, n. 1, p. 31-43, 1988.

BRASIL-SATO, M. C.; PAVANELLI, G. Digenea de Pimelodus maculatus (Osteichthyes, Pimelodidae) das bacias dos rios Sao Francisco e Parana, Brasil. Parasitologia Latinoamericana, v. 59, n. 3-4, p. 123-131, 2004.

BRASIL-SATO, M. C.; SANTOS, M. D. Metazoan parasites of Conorhynchos conirostris (Valenciennes, 1840), an endemic siluriform fish of the Sao Francisco Basin, Brazil. Revista Brasileira de Parasitologia Veterinaria, v. 14, n. 4, p. 160-166, 2005.

BURROUGH, R. J. The population biology of two species of eyefluke, Diplostomum spathaceum and Tylodelphys clavata, in roach and rudd. Journal of Fish Biology, v. 13, n. 1, p. 19-32, 1978.

BUSH, A. O.; LAFFERTY, K. D.; LOTZ, J. M.; SHOSTAK, W. Parasitology meets ecology on its own terms: Margolis et al. revisited. Journal of Parasitology, v. 83, n. 4, p. 575-583, 1997.

EIRAS, J. Elementos de ictioparasitologia. Porto: Fundacao Eng. Antonio de Almeida, 1994.

HAKALAHTI, T.; KARVONEN, A.; VALTONEN, E. T. Climate warming and disease risks in temperate regions --Argulus coregoni and Diplostomum spathaceum as case studies. Journal of Helminthology, v. 80, n. 2, p. 93-98, 2006.

HOGLUND, J.; THULIN, J. The epidemiology of the metacercariae of Diplostomum baeri and D. spathaceum in perch (Perca fluviatilis) from the warm water effluent of a nuclear power station. Journal of Helminthology, v. 64, n. 2, p. 139-150, 1990.

KOHN, A.; FERNANDES, B. M. M.; BAPTIST A FARIAS, M. F. D. Metacercariae of Diplostomum (Austroaiplostomum) compactum (Trematoda, Diplostomidae) in the eyes of Plagioscion aquamosissimus (Teleostei, Sciaenidae) from the reservoir of the Hydroelectric Power Station of Itaipu, Brazil. Memorias do Instituto Oswaldo Cruz, v. 90, n. 3, p. 341-344, 1995.

LUQUE, J. L.; POULIN, R. Use of fish as intermediate hosts by helminth parasites: a comparative analysis. Acta Parasitologica, v. 49, n. 4, p. 353-361, 2004.

LYHOLT, H. C. K.; BUCHMANN, K. Diplostomum spathaceum: effects of temperature and light on cercarial shedding and infection of rainbow trout. Diseases of Aquatic Organisms, v. 25, n. 3, p. 169-173, 1996.

MACHADO, P. M.; TAKEMOTO, R. M.; PAVANELLI, G. C. Diplostomum (Austrodiplostomum) compactum (Lutz, 1928) (Platyhelminthes, Digenea) metacercariae in fish from the foodplain of the upper Parana river, Brazil. Parasitology Research, v. 97, n. 6, p. 436-444, 2005.

MACHADO, M. P.; ALMEIDA, S. C.; PAVANELLI, G. C. ; TAKEMOTO, R. M. Ecological aspects of endohelminths parasitizing Cichla monoculus Spix, 1831 (Perciformes: Cichlidae) in the Parana river near Porto Rico, State of Parana Brazil. Comparative Parasitology, v. 67, n. 2, p. 210-217, 2000.

MARTINS, M. L.; PAIVA, A. M. F. C.; FUJIMOTO, R. Y.; SCHALCH, S. H. C.; COLOMBANO, N. C. Prevalencia, sazonalidade e intensidade de infeccao por Diplostomum (Austrodiplostomum) compactum Lutz, 1928 (Digenea, Diplostomidae), em peixes do reservatorio de Volta Grande, Estado de Minas Gerais, Brasil. Acta Scientiarum. Biological Sciences, v. 24, n. 2, p. 469-474, 2002.

NOVAES, J. L. C.; RAMOS, I. P.; CARVALHO, E. D.; SILVA, R. J. Metacercariae of Diplostomum compactum Lutz, 1928 (Trematoda: Diplostomidae) Quoy and Gaimard 1824 (Teleostei, Cichlidae) from Barra Bonita reservoir--Sao Paulo, Brazil. Arquivo Brasileiro de Medicina Veterinaria e Zootecnia, v. 58, n. 6, p. 1229-1231, 2006.

PAES, J. V. K.; CARVALHO, E. D.; SILVA, R. J. Infection levels of Austrodiplostomum compactum (Digenea, Diplostomidae) metacercariae in Plagioscion squamosissimus (Teleostei, Sciaenidae) from the Nova Avanhandava reservoir, Sao Paulo State, Brazil. Journal of Helminthology, v. 84, n. 3, p. 284-91, 2010.

PAES, J. V. K.; SANTOS, K. R.; CARVALHO, E. D.; SILVA, R. J. Ocorrencia de metacercaria de Diplostomum compactum (Trematoda, Diplostomidae) parasitando Plagioscion squamosissimus (Teleostei, Sciaenidae) proveniente do reservatorio de Nova Avanhandava, Buritama, Sao Paulo. Arquivos do Instituto Biologico, v. 70, n. 3, p. 383-387, 2003.

POJMANSKA, T. Infection of common carp, and three introduced herbivorous fish from Zabieniec fish farm, in relation to their sizes. Acta Parasitologica, v. 39, n. 1, p. 16-24, 1994.

RINTAMAKI-KINNUNEN, P.; KARVONEN, A.; ANTTILA, P.; VALTONEN, E. T. Diplostomum spathaceum metacercarial infection and colour change in salmonid fish. Parasitology Research, v. 93, n. 1, p. 51-55, 2004.

SANTOS, R. S.; PIMENTA, F. D. A.; MARTINS, M. L.; TAKAHASHI, H. K.; MARENGONI, N. G. Metacercarias de Diplostomum (Austrodiplostomum) compactum Lutz, 1928 (Digenea: Diplostomidae) em peixes do rio Parana, Brasil. Prevalencia, sazonalidade e intensidade de infeccao. Acta scientiarum. Biological Sciences, v. 24, n. 2, p. 475-480, 2002.

SEPPALA, O.; KARVONEN, A.; VALTONEN, T. Parasite-induced change in host behaviour and susceptibility to predation in an eye fluke-fish interaction. Animal Behaviour, v. 68, n. 2, p. 257-263, 2004.

TAKEMOTO, R. M.; PAVANELLI, G. C.; LIZAMA, M. A. P.; LACERDA, A. C. F.; YAMADA, F. H.; MOREIRA, L. H. A.; CESCHINI, T. L.; BELLAY, S. Diversity of parasites of fish from the upper Parana river foodplain, Brazil. Brazilian Journal of Biology, v. 69, n. 2, p. 691-705, 2009.

VALTONEN, E. T.; GIBSON, D. I. Aspects of the biology of diplostomid metacercarial (Digenea) populations occurring in fishes in different localities of northern Finland. Annales Zoologici Fennici, v. 34, n. 1, p. 47-59, 1997.

YAMADA, F. H.; MOREIRA, L. H. A.; CESCHINI, T. L.; TAKEMOTO, R. M.; PAVANELLI, G. C. Novas ocorrencias de metacercarias de Austrodiplostomum compactum (Lutz, 1928) (Platyhelminthes, Digenea) parasitas de olhos de peixes da Bacia do rio Parana. Revista Brasileira de Parasitologia Veterinaria, v. 17, n. 3, p. 163-166, 2008.

ZICA, E. O. P.; SANTOS, K. R.; RAMOS, I. P.; ZANATTA, A. S.; CARVALHO, E. D.; SILVA, R. J. First case of an infection of the metacercariae of Austrodiplostomum compactum (Lutz, 1928) (Digenea, Diplostomidae) in Hypostomus regani (Thering, 1905) (Siluriformes: Loricariidae). Pan-American Journal of Aquatic Sciences, v. 4, n. 1, p. 35-38, 2009.

Received on February 4, 2010.

Accepted on June 30, 2010.

License information: This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Rosemeire de Souza Santos (1), Natalia Marchiori (2), Vamilton Alvares Santarem (1), Haroldo Kazuyuki Takahashi (1), Jose Luis Pedreira Mourino (2) and Mauricio Laterca Martins (2) *

(1) Centro de Aquicultura, Universidade do Oeste Paulista, Presidente Prudente, Sao Paulo, Brazil. (2) Departamento de Aquicultura, Universidade Federal de Santa Catarina, Rod. Admar Gonzaga, 1346, 88040-900, Florianopolis, Santa Catarina, Brazil. * Author for correspondence. E-mail: mlaterca@cca.ufsc.br
Table 1. Rainfall, air temperature and water quality mean rates
measured at the shores of the Parana river, near Presidente Epitacio,
Sao Paulo State, Brazil.

                Rainfall     Air temperature     Water temperature
Seasons           (mm)        ([degrees]C)         ([degrees]C)

Winter 2007       3.1             21.9                 22.5
                 (0-90)       (12.6-26.3) c        (21.5-23.0) a
Spring 2007       4.6             26.8                 26.5
                 (0-54)       (19.6-32.1) a       (25.8-28.4) bc
Summer 2007       2.1             27.7                29.0 c
                 (0-28)       (24.6-29.8) a
Autumn 2008       5.7             23.7                 25.7
                 (0-82)       (16.2-28.4) b        (26.2-27.3) b
Winter 2008       0.8             20.6                 21.4
                 (0-8)        (13.0-24.8) c        (21.3-21.6) a

                  Alkalinity                          Oxygen
Seasons         (mg [L.sup.-1])        pH         (mg [L.sup.-1])

Winter 2007          17.0              7.0              7.7
                (15.0-18.0) ab                       (7.5-7.8)
Spring 2007          18.7              7.0              6.9
                 (18.0-21.0) a                       (6.3-7.2)
Summer 2007         15.0 a             6.8              5.6

Autumn 2008          16.9              7.0              6.3
                (12.0-18.0) ab      (6.8-8.0)        (3.8-7.5)
Winter 2008          13.8              7.0              7.7
                 (12.0-15.0) b                       (6.4-8.4)

* Different letters indicate significant difference
(p < 0.05) between the seasons.

Table 2. Parasitological indexes ([+ or -] standard error) and
biometry of Plagioscion squamosissimus parasitized by
Austrodiplostomum compactum from the Parana river, region of
Presidente Epitacio, Sao Paulo State, Brazil. Mean values and
variation, between parentheses, of fish weight and length,
infected fish/examined fish (IF/IE), prevalence, total number
of parasites (TNP), mean intensity and range, between
parenthesis, and mean abundance.

                  Fish           Fish                Prevalence
Seasons        weight (g)    length (cm)    IF/EF        (%)

Winter 2007       480.1          33.3       16/16        100
               (185-1360)      (25-50)
Spring 2007       626.0          33.8       15/15        100
               (162-1998)      (24-54)
Summer 2007       497.0          32.8        6/6         100
               (236-1290)     (26.5-47)
Autumn 2008       666.9          32.8       14/15       93.3
               (214-2560)      (25-52)
Winter 2008       231.2          27.8        5/5         100
                (166-276)      (26-31)

Seasons        TNP      Mean intensity        Mean abundance

Winter 2007    577     36.1 [+ or -] 7.2     36.1 [+ or -] 7.2
                            (2-90)
Spring 2007    634    45.0 [+ or -] 20.8    45.0 [+ or -] 20.8
                            (7-222)
Summer 2007    201    36.8 [+ or -] 14.4    36.8 [+ or -] 14.4
                            (12-92)
Autumn 2008    831    59.3 [+ or -] 18.7    55.4 [+ or -] 17.9
                            (2-255)
Winter 2008    148           29.6           29.6 [+ or -] 13.4
                            (1-76)

Table 3. Parasitological indexes ([+ or -] standard error) and
biometry of Geophagus surinamensis parasitized by Austrodiplostomum
compactum from the Parana river, region of Presidente Epitacio, Sao
Paulo State, Brazil. Mean values and variation, between parentheses,
of fish weight and length, infected fish/examined fish (IF/IE),
prevalence, total number of parasites (TNP), mean intensity and
range, between parentheses, and mean abundance.

                  Fish           Fish                Prevalence
Seasons        weight (g)    length (cm)    IF/EF        (%)

Winter 2007       147.5          20.2        0/15         0
                (85-215)       (17-23)
Spring 2007       130.4          19.6        0/5          0
                (122-144)      (19-20)
Summer 2007         -             -           -           -

Autumn 2008       179.8          21.2       13/15       86.6
                (132-254)      (18-23)
Winter 2008       144.0          19.8        5/5         100
                (108-178)      (18-22)

Seasons        TNP       Mean intensity          Mean abundance

Winter 2007     0              0 a                     0

Spring 2007     0              0 a                     0

Summer 2007     -               -                      -

Autumn 2008    157    12.0 [+ or -] 4.1 bc    10.4 [+ or -] 3.7 b
                             (0-53)
Winter 2008     91     18.2 [+ or -] 7.6 c    18.2 [+ or -] 7.6 c
                             (3-46)

* Different letters indicate significant difference
between months (p < 0.05).

Table 4. Parasitological indexes([+ or -] standard error) and
biometry of Hoplias malabaricus parasitized by Austrodiplostomum
compactum from Parana river, region of Presidente Epitacio, Sao
Paulo State, Brazil. Mean values and variation, between parentheses,
of fish weight and length, infected fish/examined fish (IF/IE),
prevalence, total number of parasites (TNP), mean intensity and
range, between parentheses, and mean abundance.

                  Fish           Fish                Prevalence
Seasons        weight (g)    length (cm)    IF/EF        (%)

Winter 2007       643.5          40.1        7/15       46.6
               (410-1025)      (35-47)
Spring 2007       407.3          35.0        2/3        66.6
                (250-580)      (29-41)
Summer 2007         -             -           -           -

Autumn 2008       729.0          40.3        5/6        83.3
               (394-1022)      (32-46)
Winter 2008       609.5          39.5        3/4        75.0
                (360-782)      (35-44)

Seasons        TNP      Mean intensity        Mean abundance

Winter 2007    247     35.2 [+ or -] 6.9     16.4 [+ or -] 1.7
                            (0-57)
Spring 2007     26     13 [+ or -] 11.1      8.6 [+ or -] 7.8
                            (0-24)
Summer 2007     -              -                     -

Autumn 2008     68     13.6 [+ or -] 6.6     11.3 [+ or -] 5.9
                            (0-38)
Winter 2008    214    71.3 [+ or -] 57.4    53.5 [+ or -] 43.5
                            (0-184)

Table 5. Parasitological indexes ([+ or -] standard error) and
biometry of Cichla sp. parasitized by Austrodiplostomum compactum
from Parana river, region of Presidente Epitacio, Sao Paulo State,
Brazil. Mean values and variation, between parenthesis, of fish
weight and length, infected fish/examined fish (IF/IE), prevalence,
total number of parasites (TNP), mean intensity and range, between
parentheses, and mean abundance.

                  Fish           Fish                Prevalence
Seasons        weight (g)    length (cm)    IF/EF        (%)

Winter 2007       450.6          29.7        3/13        23
               (225-2365)      (26-53)
Spring 2007       311.3           29         2/3        66.6
                (296-320)      (28-30)
Summer 2007         -             -           -           -

Autumn 2008       378.5          30.2        7/7         100
                (140-498)      (22-33)
Winter 2008         -             -           -           -

Seasons        TNP     Mean intensity        Mean abundance

Winter 2007     4     1.3 [+ or -] 0.3     0.3 [+ or -] 0.2 a
                            (0-2)
Spring 2007     17    8.5 [+ or -] 6.5    5.6 [+ or -] 4.7 ab
                           (0-15)
Summer 2007     -             -                    -

Autumn 2008     50    7.1 [+ or -] 3.3     7.1 [+ or -] 3.3 b
                           (1-21)
Winter 2008     -             -                    -

* Different letters indicate significant difference
between the months (p < 0.05).

Table 6. Parasitological indexes and sites of infection of
Austrodiplostomum compactum collected in fishes from Brazil.

Hosts                         n     p (%)          MI

Anostomidae
Schizodon borellii            15     6.6           -
Auchenipteridae
Auchenipterus osteomystax     2      50.0          -
Characidae
Serrasalmus maculatus         3      33.3          -
Cichlidae
Cichla monoculus              40     65.0         7.8
C. monoculus                 136     5.2          2.7
C. ocellaris                  80     56.2         6.0
C. ocellaris                  66     12.5         3.5
Cichla sp.                    23     52.1         5.9
Cichlasoma paranaense         25     12.0         1.0
Crenicichla britskii          44     22.7         6.2
Geophagus brasiliensis        50     14.0         1.5
G. surinamensis               39     46.1         13.7
Satanoperca pappaterra        89     71.9         8.0
Curimatidae
Cyphocharax Gilbert           60     1.7          1.0
Erythrinidae
Hoplias malabaricus          198     11.1         1.4
H. malabaricus                27     66.6         32.6
Loricariidae
Hypostomus regani             8      25.0          -
Pimelodidae
Conorhynchus conirostris      24     8.3          7.5
Pimelodus maculatus           82     17.0         1.0
Sciaenidae
Plagiosaon squamosissimus    378     94.3         21.6
P. squamosissimus             61     92.6         39.0
P. squamosissimus             70     52.8         2.6
P. squamosissimus             81     95.0         38.9
P. squamosissimus             17    100.0    2-100 per eye
P. squamosissimus             51     98.0         44.1

Hosts                         MA           Site of infection

Anostomidae
Schizodon borellii            0.1            Aqueous humor
Auchenipteridae
Auchenipterus osteomystax     0.5            Aqueous humor
Characidae
Serrasalmus maculatus         0.3            Aqueous humor
Cichlidae
Cichla monoculus              5.1    Cranial cavity/vitreous humor
C. monoculus                  0.1                 Eyes
C. ocellaris                  5.3                 Eyes
C. ocellaris                   -                  Eyes
Cichla sp.                    3.0             Crystalline
Cichlasoma paranaense         0.1    Cranial cavity/vitreous humor
Crenicichla britskii          1.4    Cranial cavity/vitreous humor
Geophagus brasiliensis        0.2                 Eyes
G. surinamensis               6.3             Crystalline
Satanoperca pappaterra        5.7    Cranial cavity/vitreous humor
Curimatidae
Cyphocharax Gilbert            0                  Eyes
Erythrinidae
Hoplias malabaricus           0.1    Cranial cavity/vitreous humor
H. malabaricus               20.5             Crystalline
Loricariidae
Hypostomus regani             0.1            Aqueous humor
Pimelodidae
Conorhynchus conirostris      0.6              Gills/Eyes
Pimelodus maculatus           0.1                 Eyes
Sciaenidae
Plagiosaon squamosissimus    20.2                 Eyes
P. squamosissimus            43.0                 Eyes
P. squamosissimus              -                  Eyes
P. squamosissimus            37.0    Cranial cavity/vitreous humor
P. squamosissimus              -                  Eyes
P. squamosissimus            43.2             Crystalline

Hosts                                  Reference

Anostomidae
Schizodon borellii                Yamada et al. (2008)
Auchenipteridae
Auchenipterus osteomystax         Yamada et al. (2008)
Characidae
Serrasalmus maculatus             Yamada et al. (2008)
Cichlidae
Cichla monoculus                 Machado et al. (2005)
C. monoculus                     Machado et al. (2000)
C. ocellaris                      Santos et al. (2002)
C. ocellaris                     Martins et al. (2002)
Cichla sp.                           Current study
Cichlasoma paranaense            Machado et al. (2005)
Crenicichla britskii             Machado et al. (2005)
Geophagus brasiliensis           Azevedo et al. (2006)
G. surinamensis                      Current study
Satanoperca pappaterra           Machado et al. (2005)
Curimatidae
Cyphocharax Gilbert              Abdallah et al. (2005)
Erythrinidae
Hoplias malabaricus              Machado et al. (2005)
H. malabaricus                       Current study
Loricariidae
Hypostomus regani                 Yamada et al. (2008)
Pimelodidae
Conorhynchus conirostris     Brasil-Sato and Santos (2005)
Pimelodus maculatus              Bachmann et al. (2007)
Sciaenidae
Plagiosaon squamosissimus          Paes et al. (2010)
P. squamosissimus                 Santos et al. (2002)
P. squamosissimus                Martins et al. (2002)
P. squamosissimus                Machado et al. (2005)
P. squamosissimus                  Kohn et al. (1995)
P. squamosissimus                    Current study
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Author:Santos, Rosemeire de Souza; Marchiori, Natalia; Santarem, Vamilton Alvares; Takahashi, Haroldo Kazuy
Publication:Acta Scientiarum. Biological Sciences (UEM)
Date:Apr 1, 2012
Words:5020
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