Highest Mean Intensity Research Articles

Co-infection and morphometrics of three clinostomatids (Digenea: Clinostomatidae) in Tilapia guinensis Bleeker, 1862 from Opi lake, Nigeria

Co-infection and morphometrics of helminth parasites of Tilapia guinensis in Opi Lake (GPS N06.75275*, E007.49104*), were studied from (Nov 2007– Oct 2008) using multiple fishing gear techniques; cast nets, hook and line, and seine nets (150 mm – 200 mm). The parasites recovered were C. tilapiae, C. complanatum and E. heterostomum. The prevalence was low, indicative of parasitic infection in the wild. Prevalence of (33.9 %) was recorded in C. complanatum, (7.2 %) in E. heterostomum and (12.6 %) in C. tilapiae. But high mean intensity was suggestive of heavy parasite burden; C. complanatum (4.8), C. tilapiae (2.8), and E. heterostomum (5.1). Morphometrics of the parasites showed no significance difference in the distance between oral and ventral suckers. However, they differed in all other parts significantly (p < 0.05). In the rank-abundance curve for parasite communities, C. complanatum was most abundant (pi 0.63). Differential parasitic effects were due to selection for relatively better adaptiveness to host’s microhabitats, more population size, better host location, and larger body size. Consequently, this resulted in a trade-off between larger morphometric parts and population size among the parasites

HELMINTHS OF MURRES (ALCIDAE: URIA SPP.): MARKERS OF ECOLOGICAL CHANGE IN THE MARINE ENVIRONMENT

Seabirds are prominent components of the North Atlantic marine environment, and their parasites offer an insight into seabird ecologic interactions. Parasites also provide vital information on historic biogeography of host associations and thus may reveal broad changes in the marine ecosystem. Helminths of Common Murres (Uria aalge) and Thick-billed Murres (Uria lomvia) in the northwest Atlantic marine environment were assessed to determine parasite community composition and changes in their parasite fauna since the 1960s. In total, 623 helminths, representing Digenea, Eucestoda, Nematoda, and Acanthocephala, were recorded from 100 Common and Thick-billed Murres collected from breeding colonies along the coasts of Labrador, Newfoundland, and Greenland. Parasite communities differed from those reported from the 1960s, and over 85% of the specimens were tapeworms (mostly in the genus Alcataenia). The high prevalence (26%) and mean intensity (14.6) of A. longicervica, a Pacific species recorded recently from Newfoundland, indicates that this tapeworm was established in the Atlantic by 2006. Significantly higher A. longicervica prevalence (>53%) and mean intensity (27.3) in the murres from Greenland and in wintering murres compared to murres from breeding colonies in Labrador and Newfoundland suggest a mechanism for the introduction of this species to the Atlantic. Periodic mixing of populations of Thysanoessa species, the euphausiid intermediate host of Alcataenia, occurs along the seas adjacent to the North Pacific and those along the Siberian Arctic. The mixing of infected Thysanoessa likely exposed North Atlantic and Arctic murres, which are geographically isolated from Pacific murres, to this tapeworm. The greater prevalence of A. longicervica in Thick-billed Murres was consistent with diet analyses, which revealed a greater proportion of euphausiids.

Prevalence and intensity of Otodectes cynotis in kittens from Thessaloniki area, Greece

From May 2007 to May 2008 we have examined by otoscopy a total number of 214 cats, aged between 0 and 6 months, brought in for their first veterinary examination to a private veterinary clinic. All cats were of urban origin. In all positive cats we performed a washing of the ear using warm paraffin oil in order to determine intensity of infection. Statistical analysis was performed using the Chi-square test. A total number of 30 cats were found to be infected with Otodectes cynotis (prevalence 14.02%). Prevalence of infection was significantly ( p < 0.05) higher in cats aged between 3 and 6 months (17.58%) than in cats aged below 3 months (11.38). Intensity of infection ranged between 7 and 85 (mean intensity 35.60) mites per infected cat. The same age group of cats between 3 and 6 months had significantly ( p < 0.05) higher mean intensity (47.19) compared to cats aged under 3 months (22.36). No statistical significance was found between males and females for neither prevalence nor intensity. Differences and similarities with other studies are discussed.

Monogenoidea (Dactylogyridae) em tilápias-do-nilo cultivadas sob diferentes densidades de estocagem em tanques-rede

Avaliaram-se a prevalência e a intensidade de infecção por Monogenoidea em tilápias-do-nilo (Oreochromis niloticus) cultivadas sob diferentes densidades de estocagem em tanques-rede de 4m³. O delineamento experimental foi inteiramente ao acaso, com quatro tratamentos - densidades (D) de D1=250, D2=300, D3=350 e D4=400 peixes/m³, três repetições por tratamento, utilizando-se 360 peixes capturados e analisados no período de fevereiro a junho de 2003. Os parâmetros físico-químicos da água foram mensalmente monitorados. Observaram-se prevalências de 52,8; 62,5; 69,4; 83,3; 58,3% e intensidade média parasitária de 112,8; 65,7; 274,0; 97,8; 100,2 de Dactylogyrus sp. (Monogenoidea: Dactylogyridae). Não houve relação da prevalência e intensidade de infecção com a densidade de cultivo, porém foi verificado efeito quadrático (P&lt;0,05) da intensidade parasitária em função do mês. Verificaram-se maior intensidade média de infecção (274) e elevada prevalência (83,3%) nos meses em que a temperatura e a transparência da água oscilaram abaixo dos limites recomendados para o conforto térmico e bem-estar das tilápias.

Anisakid parasites of the pouting (Trisopterus luscus) from the Cantabrian Sea coast, Bay of Biscay, Spain

An epidemiological survey was undertaken of anisakids in 139 specimens (length: 13.2-24.5 cm) of pouting or bib (Trisopterus luscus) captured off the coast of northern Spain in the Cantabrian Sea. Third-stage larvae of two species of nematodes, Anisakis larvae type I and Hysterothylacium aduncum, were isolated. One adult female H. aduncum was also detected in the intestine of one pouting. Total prevalence of anisakids was 88.5%. Hysterothylacium aduncum and Anisakis showed, respectively, prevalence of 87.8% and 22.3%, mean intensity of 19.7 and 3.5, and mean abundance of 17.3 and 0.8. Analysis of infection parameters as a function of host length revealed a much higher prevalence in pouting specimens with length < 20 cm (94.4% for H. aduncum; 28.0% for Anisakis) than in those with length > or = 20 cm (65.6% for H. aduncum; 3.1% for Anisakis). The high mean intensity of Anisakis in muscle of parasitized pouting (5.9) may pose human health risks, although these are minimized by eating only thoroughly cooked pouting, as is the custom in Spain.

Helminth Parasites in Chaunus marinus and Cranopis valliceps (Anura: Bufonidae) from Lagunas Yalahau, Yucatan, Mexico

Eight helminth taxa were found parasitizing Chaunus marinus (n = 40) and Cranopsis valliceps (n = 40) from the Parque Estatal Lagunas Yalahau, Yucatan, Mexico. Seven taxa (2 digeneans: Langeronia macrocirra, Mesocoelium monas; 1 acanthocephalan: Oncicola sp.; 3 nematodes: Rhabdias füleborni, Aplectana itzocanensis, Cruzia morleyi; and a nematode larva) were found in C. marinus, while 4 taxa (all nematodes: Rhabdias fuelleborni, Aplectana itzocanensis, Ozwaldocruzia sp., and a nematode larva) were present in C. valliceps. Nematodes, particularly A. iztocanensis, showed high prevalence, mean abundance, and mean intensity values for both species of amphibians. The occurrence of R. fuelleborni, M. monas, L. macrocirra, and C. morleyi in these amphibians from the Yucatan Peninsula confirms their neotropical distribution, while the presence of A. itzocanensis increases its geographical distribution, suggesting a preference by neotropical, rather than neartic areas.

Ultraweak emissions of developing Xenopus laevis eggs and embryos

We measured ultraweak emissions of the Xenopus laevis eggs and embryos during normal development and under the influence of stress factors in a spectral range of 250 to 800 nm using a photomultiplier. The registered emissions were analyzed by several basic characteristics: mean intensity, histograms, kurtosis, linear trends, and Fourier spectra. We followed relationships between these parameters and developmental stage, as well as the number of individuals in optic contact with each other. The ultraweak emissions did not differ from the background at all developmental stages according to the mean intensity. But Fourier analysis revealed the reliable presence of a number of spectral lines of ultraweak emission, predominantly in the ranges of 10-20 and 30-40 Hz, in the embryos at developmental stages 2 to 11. The intensity of ultraweak emissions reliably decreased within the first 10 min after egg activation and fertilization, as well as in the case of optic interaction between groups of embryos. Sharp cooling, increase in osmotic medium pressure, and transfer in a Ca(2+)- and Mg(2+)-free medium induced a short term (approximately 1-5 min) increase in the mean intensity of ultraweak emission. We studied specific features of ultraweak emissions from different parts of the embryo. The intensity of emission from the animal part of early blastula exceeded those from the vegetal area and entire embryo. Separated fragments of the lateral ectoderm at the neurula stage had higher mean intensities of ultraweak emission than intact embryos at the same developmental stages.

PARASITES OF JUVENILE BROOK TROUT (SALVELINUS FONTINALIS) FROM HUNT CREEK, MICHIGAN

Four parasite species (Crepidostomum cooperi, Cystidicoloides ephemeridarum, Acanthocephalus dirus, Salmincola edwardsii) infected 215 juvenile brook trout (105 young-of-year; 110, 1-yr-old) from Hunt Creek, Michigan, in 2003, 2004, and 2005. Prevalences of these species in 2004 (main study year) varied from 29 to 37%. Crepidostomnum cooperi had the highest mean intensity and mean abundance, followed by C. ephemeridarum. The number of fish infected with each parasite species was significantly higher in 1-yr-old fish than in young-of-year fish. Also, the mean intensities and mean abundances of C. cooperi and C. ephemeridarum and the mean abundance of A. dirus were significantly higher in older fish. The mean intensity of C. cooperi and prevalence of A. dirus were significantly higher in fish between creek sections. Fish length had a significant positive effect on the abundances of C. cooperi and C. ephemeridarum; parasite species richness, on the abundances of A. dirus and S. edwardsii; and parasite species richness in the 2003 and 2004 trout cohorts, respectively. Crepidostomum cooperi, C. ephemeridarum, A. dirus, and S. edwardsii commonly infect Michigan brook trout. The small number of parasite species infecting Hunt Creek brook trout is similar to the number of parasite species of brook trout from other Michigan creeks.

Helminth parasites of the African lizard Agama agama (Squamata: Agamidae), in Lagos, Nigeria

Agama agama, the agamid rainbow lizard, has been reported to serve as transport and reservoir host to several protozoan and helminth parasites. We randomly sampled 310 specimens between May and July, 2005, at Oyingbo, Lagos, Nigeria (6 degrees 34'60" N-3 degrees 19'59" E and 6 degrees 34'60" N-3 degrees 19'59" E).They harboured four species of nematodes: Strongyluris brevicaudata, Parapharyngodon awokoyai, Capillaria sp. and Oxyuris sp.; one of Cestoda, Oochoristica agamae; one of Trematoda, Mesocoelium monas; and one of Pentastomida, Raillietiella sp. Strongyluris brevicaudata had the highest prevalence of infection (82.3%), followed by P. awokoyai (74.5%), Raillietiella (10.3%), Capillaria sp. (8.4%) and O. agamae (7.4%). M. monas and Oxyuris sp. had low prevalences: 1.61% each. Raillietiella sp. and Capillaria sp. can cause localized inflammation and intestinal infections in humans. The prevalence of infection was higher in larger adult lizards. Prevalence in males was 97.6% (94.1% in females). In four of the helminth species, intensity of infection was higher in male lizards. Parasite intensity was highest in the rectum, followed by the intestine (p<0.05). Infection intensity was, to a large extent, dependent on the type of parasite, and age of lizard. During May, P. awokoyai had its highest mean intensities and prevalence. The prevalence and mean intensity of helminthes varied with the month of collection (both p<0.05). For the three months studied, prevalence and mean intensity of S. brevicaudata were highest in June (July for the other species).

Population dynamics of Chaetogaster limnaei (Oligochaeta: Naididae) in the field populations of freshwater snails and its implications as a potential regulator of trematode larvae community

The objectives of this work were to study (1) the population dynamics of Chaetogaster limnaei in the field populations of freshwater snails and the implications for the species as a potential regulator of the trematode larvae community and (2) prevalence and intensity of C. limnaei in relation to host species, host size, and season. This study was conducted at Al-Salam Canal and Al-Abtal village (new cultivated area in north Sinai). The samples were collected from March 2004 to February 2005. The natural infection rate by trematodes and C. limnaei was assessed monthly. Thirteen species of snails were examined for C. limnaei infection, five species were found infected. There were positive correlations between host size and both combined prevalence and mean intensity in all hosts. The data demonstrated that prevalence in Bulinus truncatus was higher when compared with other hosts. Bellamya unicolor has higher mean intensity when compared with other host species. A significant difference was found between host species and both prevalence and intensity. There were spatial and temporal variations in prevalence and mean intensity in most hosts, and the data suggest some seasonality. A negative correlation was found between prevalence of C. limnaei and trematode infection. C. limnaei did not co-occur with trematode larvae in infected hosts indicating that the oligochaete may protect the hosts from trematode infection. B. unicolor was recorded for the first time as a host for C. limnaei. C. limnaei may be a potential regulator of the trematode community in freshwater snails. In conclusion, this study demonstrated that C. limnaei, symbiotically associated with snail vector of parasitic diseases, may have important implications with respect to biological control and/or changes in the epizootiology of native parasites in the study area.

Parasites of Tadpole Madtom, Noturus gyrinus (Mitchill, 1817) (Ictaluridae), from Silver Creek, Michigan, U.S.A., with a Checklist of the North American Parasites of Tadpole Madtom

Abstract Ninety-two tadpole madtom, Noturus gyrinus, collected in May through August 2005 from Silver Creek in Lower Michigan, were examined for parasites. Ten parasite species (5 Digenea, 1 Monogenea, 1 Cestoda, 1 Nematoda, 1 Acanthocephala, and 1 Ciliophora) infected madtom. Macroderoides sp. and Alloglossidium corti had the highest prevalence and mean abundance, respectively. Although Maritreminoides sp. had the highest mean intensity, it is considered an accidental parasite of tadpole madtom. Azygia sp., Macroderoides sp., Maritreminoides sp., and Neoechinorhynchus sp. are reported for the first time from tadpole madtom. This study is the first account of parasites of tadpole madtom from Michigan and represents the largest number of tadpole madtom examined for parasites from one locality in North America. A checklist of parasites of tadpole madtom from published records in North America is also presented.

Endohelminth fauna of the marsh frog Rana ridibunda from Lake Hazar, Turkey

In this study, 236 marsh frogs Rana ridibunda collected from Lake Hazar (Elazig, Turkey) at 15 d intervals between March 2001 and February 2002 were examined for endohelminths; of these, 148 (62.71%) frogs were found to be infected with helminths. In total, 9 helminth species (3 trematodes, 5 nematodes and 1 acanthocephalan) were identified. We observed Gorgoderina vitelliloba (prevalence 2.97%) in the urinary bladder, Haematoloechus variegatus (4.66%) and Rhabdias bufonis (8.90%) in the lung, Pleurogenoides medians (1.69%), Oswaldocruzia filiformis (3.81 %) and Acanthocephalus ranae (26.27 %) in the small intestine, Neoxysomatium brevicaudatum (16.95%) and Cosmocercoides sp. (3.39%) in the large intestine, and Eustrongylides excisus (14.41%) in the body cavity and on,the stomach. No helminth was found in the spleen, kidney, gall bladder, liver, heart or muscle. Of the 9 helminth species identified, Acanthocephalus ranae (26.27 %) had the highest prevalence and abundance and Oswaldocruzia filiformis (8.33+/-4.09) had the highest mean intensity.

From a Whisper to a Roar: Adaptation to the Mean and Variance of Naturalistic Sounds

In this issue of Neuron, Nagel and Doupe make a quantitative assessment of temporal adaptation in the avian auditory forebrain, capturing seemingly complex responses with a simple linear-nonlinear (LN) model of kinetics and gain. A comparison of these findings with similar results in the early visual system shows an important unifying picture of efficient sensory processing and adaptation.

Re-infection patterns of ascariasis among school children in Ogun State, Nigeria

A study was conducted to determine the direct prevalence, intensity and re-infection pattern of ascariasis among school pupils aged 6-17 years in Ogun State, Nigeria; 2,837 primary school pupils randomly selected from twenty schools in five Local Government Areas (LGAs) namely: Odeda, Obafemi/Owode, Ewekoro, Ado-Odo/Otta, and Ogun Waterside were enlisted for the study. Drug (Levamisole) administration was used to determine the direct prevalence, intensity and the re-infection patterns of infection. The overall direct prevalence for A.lumbricoides was 48.5%. Obafemi/Owode had the highest mean infection rate of 62.6%, followed by Ogun Waterside (59.19%), Odeda (44.8%), Ewekoro (34.2%) and Ado-Odo/Otta (25.6%). Male pupils were slightly more infected (51.9%) than females (48.1%) and also had higher mean intensity (2.2) than females (1.7). Statistical analysis showed no significant difference between the infection rates in both sexes (t=2.60, p=0.234). The cumulative numbers of worms expelled by pupils in the LGAs were Ogun Waterside 778 (39.5%), Obafemi/Owode 768 (39%), Odeda 216 (11%), Ewekoro 152 (7.7%) and Ado-Odo/Otta 55 (2.8%). The morphometric studies revealed that of the 1969 worms voided, adult worms accounted for 92.7% while young worms formed only 7.3%. Re-infection of pupils with ascariasis from different LGAs varied. The calculated monthly re-infection rates (X) were: Ewekoro (1.6%), Odeda (2.3%), Ado-Odo/Otta (2.3%), Ogun Waterside (3.8%), and Obafemi/Owode (4.2%); with a mean value of 2.84% for Ogun State. The re-infection time (N months) are Ado-Odo/Otta (12.7), Ogun Waterside (21.8), Obafemi/Owode (22.92), Odeda (25.45), and Ewekoro (25.9). The mean value for N in Ogun State was 21.75, which implies that it would require 22 months for initial equilibrium of A.lumbricoides infection to be attained in school pupils in Ogun State, Nigeria. Keywords : Ascaris lumbricoides , reinfection, primary school pupils, Ogun State Nigerian Journal of Parasitology Vol. 25, 2004: 7-13

Effect of age, sex and season on the prevalence and intensity of helminth infections in domestic pigeons (Columba livia) from Bursa Province, Turkey

The one-year study reported in this paper was carried out from April 2002 to March 2003 in domestic pigeons (Columba livia) of Bursa Province (Turkey) to determine the occurrence of helminth species and to evaluate the effect of host age, sex and season on their prevalence and intensity. A total of 100 (31 young and 69 adult) domestic pigeons were necropsied and examined. The results of necropsies revealed that 74 pigeons harboured helminth infections. Three helminth species were identified: Baruscapillaria obsignata (63%), Ascaridia columbae (42%) and Raillietina echinobothrida (1%). There were no significant differences in the prevalence of B. obsignata and A. columbae by host age and sex. Significantly the highest prevalence rate of A. columbae was observed in the autumn months, but there was no significant difference in the seasonal prevalence of B. obsignata. The mean intensity of B. obsignata and A. columbae was higher in adults than in young pigeons but it did not differ significantly between the two sexes. The highest mean intensity rate of B. obsignata was observed in the autumn, while there was no significant difference for A. columbae with regard to season. From the data obtained in this study it can be concluded that in regions with similar climatic conditions as those in the present study area, pigeon breeders should be cautioned especially of B. obsignata and A. columbae infections of adult pigeons in the autumn months.

Neoechinorhynchus curemai (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus (Osteichthyes: Prochilodontidae) from the Paraná River, Brazil

This work evaluated parasitic infections by Neoechinorhynchus curemai (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus captured between August 2000 and August 2001 in the Paraná River, Presidente Epitácio, São Paulo, Brazil. Of 87 fishes examined, 59 were infected (25 males and 34 females). High mean intensities occurred in August 2000 (45.2, range 2–204), September 2000 (28.5, range 11–73), October 2000 (59.3, range 2–250) and February 2001 (27.3, range 3–73). There was no relationship of rainfall with mean intensity and prevalence. Males were more parasitized ( P < 0.05) than females. This work contributes to the knowledge of helminth parasites of fish from a little studied region of the Paraná River, showing diversity in their fauna when compared to other places in the same river.

The effect of physical activity in leisure time on neck and upper limb symptoms

Background. Little is known of the preventive effects of physical activity in leisure time on neck and upper limb symptoms. Methods. A cohort of 1742 employees was selected from a prospective cohort study with a follow-up period of 3 years. Independent variables were sporting activities and physically active commuting. Outcome measures were neck/shoulder symptoms and elbow/wrist/hand symptoms as well as sickness absence due to these symptoms. To analyze the data, the generalized estimating equation (GEE) method was used, with adjustment for individual characteristics, such as age, gender, lifestyle, and the outcome at baseline. Results. Practicing sports for at least 10 months a year decreased the risk of neck/shoulder symptoms (OR: 0.82; CI: 0.67–0.99), sickness absence (OR: 0.48; CI: 0.28–0.84), and long-term sickness absence (OR: 0.37; CI: 0.17–0.84) due to neck or upper limb symptoms. A high mean intensity (≥3 h per week) of sporting activities had less effect than the continuation of these activities throughout the year. Conclusion. Sustained sporting activities have a favorable effect on neck/shoulder symptoms and on sickness absence due to neck or upper limb symptoms. An effect of physically active commuting could not be demonstrated, although there was a tendency towards a favorable effect on sickness absence.

METAZOAN PARASITE FAUNA AS A BIOLOGICAL TAG FOR THE HABITAT OF THE FLOUNDER HIPPOGLOSSINA MACROPS FROM NORTHERN CHILE, IN A DEPTH GRADIENT

Quantitative changes in the parasite communities of the flounder Hippoglossina macrops (Steindachner) were studied along a depth gradient. Samples were obtained from the waters off Coquimbo, Chile (29 degrees 18'S to 30 degrees 50'S), at depths ranging from 160 to 342 m. Samples were assigned to 3 depths, i.e., shallow water (less than 200 m), midwater (from 200 to 300 m), and deep water (more than 300 m). Twelve parasite species were recorded: Neoheterobothrium chilensis and Entobdella hippoglossi (Monogenea); Holobomolochus chilensis and Protochondria longicauda (Copepoda); Gliptonobdella sp. (Hirudinea); Nybelinia surmenicola, Scolex pleuronectis, and Neobothriocephalus adspinosus (Cestoda); Floridosentis sp. and Corynosoma australe (Acanthocephala); Anisakidae (Nematoda); and an unidentified hemiurid (Digenea). Univariate analyses showed that C. australe has its highest prevalence and mean intensity of infection in hosts from shallow waters. Floridosentis sp. showed significant differences along the depth gradient, with higher mean intensity and prevalence of infection in fish from midwater. Among the ectoparasites, only N. chilensis exhibited differences in mean intensity with depth, where intensity of infection increased with depth of host habitat. A canonical multivariate analysis demonstrated that parasite burdens can be a good predictor of the environment (shallow, mid-, or deep water) occupied by the flounders.

Boreal forest fires burn less intensely in Russia than in North America

Around 5–20 million hectares of boreal forest burns annually, mainly in Russia and North America. However, there are reports of significant differences in predominant fire type between these regions, which may have major implications for overall emissions of carbon, gases and aerosols. We examine boreal forest fire intensities via MODIS observations of fire radiative energy release rate. Results support the contention of a consistent difference in fire intensity and mean fuel consumption in Russia and North America, due to differences in dominant fire type. North American fires have higher mean intensities, increasing in proportion to percentage tree cover, characteristics indicating likely crown fire dominance. Russian fires have lower mean intensities, independent of percentage tree cover, characteristics more indicative of surface fire activity. Per unit area burnt, the results suggest Russian fires may burn less fuel and emit fewer products to the atmosphere than do those in North America.

Occurrence of acanthocephalans in largemouth bass and smallmouth bass (Centrarchidae) from Gull Lake, Michigan.

A total of 65 largemouth bass, Micropterus salmoides, and 27 smallmouth bass, M. dolomieu, collected in April-September 2000 and April-July 2001 from Gull Lake, Michigan, were examined for acanthocephalans. Leptorhynchoides thecatus and Neoechinorhynchus cylindratus infected all the bass examined. Leptorhynchoides thecatus had the highest mean intensity (258.2 +/- 185.4 in 2000 and 145.0 +/- 61.0 in 2001) of the species infecting smallmouth bass. Although N. cylindratus had higher mean intensities (42.1 +/- 37.9 in 2000 and 68.9 +/- 70.5 in 2001) than did L. thecatus in largemouth bass, the values were not significantly different between bass species. The prevalence, mean intensity, and mean abundance of Pomphorhynchus bulbocolli in the bass species were below the values for the other acanthocephalan species. Leptorhynchoides thecatus and N. cylindratus are the most abundant intestinal helminths in bass from Gull Lake.