Intestinal distribution and fecundity of two species ofDiplostomumparasites in definitive hosts

This paper investigated the intestinal distribution and fecundity of 2 species ofDiplostomumparasites,D. spathaceumandD. pseudospathaceum, in 2 species of definitive hosts, herring gull (Larus argentatus) and common gull (L. canus), using both empirical field data and experimental infections. At the level of individual hosts, the parasite species occupied different parts within the intestine, but the fecundity of the worms, measured as the number of eggs in the uterus, did not differ between the parasite species except in wild common gulls. Interestingly, egg numbers in individual hosts were positively correlated between the parasite species suggesting that some birds provided better resources for the parasite species. At the host population level, fecundity of the worms did not differ between the host species or between adult birds and chicks. Both parasite species were also aggregated to the same host individuals and it is likely that aggregation is transferred to gulls from fish intermediate hosts. Individual differences in suitability and parasite numbers between hosts provide important grounds and implications for epidemiological model-based parasite prevention strategies.

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The population dynamics of competition between parasites

Parasitology ◽

10.1017/s0031182000057401 ◽

1985 ◽

Vol 91 (2) ◽

pp. 317-347 ◽

Cited By ~ 124

Author(s):

A. P. Dobson

Keyword(s):

Population Dynamics ◽

Parasite Species ◽

Interference Competition ◽

Population Level ◽

Experimental Tests ◽

Theoretical Models ◽

Control Agent ◽

Host Population ◽

Free Living ◽

The Impact

A number of published studies of competition between parasite species are examined and compared. It is suggested that two general levels of interaction are discernible: these correspond to the two levels of competition recognized by workers studying free-living animals and plants: ‘exploitation’ and ‘interference’ competition. The former may be defined as the joint utilization of a host species by two or more parasite species, while the latter occurs when antagonistic mechanisms are utilized by one species either to reduce the survival or fecundity of a second species or to displace it from a preferred site of attachment. Data illustrating both levels of interaction are collated from a survey of the published literature and these suggest that interference competition invariably operates asymmetrically. The data are also used to estimate a number of population parameters which are important in determining the impact of competition at the population level. Theoretical models of host-parasite associations for both classes of competition are used to examine the expected patterns of population dynamics that will be exhibited by simple two-species communities of parasites that utilize the same host population. The analysis suggests that the most important factor allowing competing species of parasites to coexist is the statistical distribution of the parasites within the host population. A joint stable equilibrium should be possible if both species are aggregated in their distribution. The size of the parasite burdens at equilibrium is then determined by other life-history parameters such as pathogenicity, rates of resource utilization and antagonistic ability. Comparison of these theoretical expectations with a variety of sets of empirical data forms the basis for a discussion about the importance of competition in natural parasite populations. The models are used to assess quantitatively the potential for using competing parasite species as biological control agents for pathogens of economic or medical importance. The most important criterion for identifying a successful control agent is an ability to infect a high proportion of the host population. If such a parasite species also exhibits an intermediate level of pathology or an efficient ability to utilize shared common resources, antagonistic interactions between the parasite species contribute only secondarily to the success of the control. Competition in parasites is compared with competition in free-living animals and plants. The comparison suggests further experimental tests which may help to assess the importance of competition in determining the structure of more complex parasite-host communities.

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Molecular identification of four Sarcocystis species in the herring gull, Larus argentatus, from Lithuania

Parasites & Vectors ◽

10.1186/s13071-019-3869-x ◽

2020 ◽

Vol 13 (1) ◽

Cited By ~ 2

Author(s):

Petras Prakas ◽

Dalius Butkauskas ◽

Evelina Juozaitytė-Ngugu

Keyword(s):

Light Microscopy ◽

Current Knowledge ◽

Bird Species ◽

Larus Argentatus ◽

Infected Bird ◽

Herring Gull ◽

Sarcocystis Species ◽

Intermediate Hosts ◽

Its1 Sequence ◽

Herring Gulls

Abstract Background Birds of the family Laridae have not been intensively examined for infections with Sarcocystis spp. To date, sarcocysts of two species, S. lari and S. wobeseri, have been identified in the muscles of gulls. The aim of the present study was to evaluate the species richness of Sarcocystis in the herring gull, Larus argentatus, from Lithuania. Methods In the period between 2013 and 2019, leg muscles of 35 herring gulls were examined for sarcocysts of Sarcocystis spp. Sarcocystis spp. were characterised morphologically based on a light microscopy study. Four sarcocysts isolated from the muscles of each infected bird were subjected to further molecular examination. Sarcocystis species were identified by means of ITS1 sequence analysis. Results Sarcocysts were detected in 9/35 herring gulls (25.7%). Using light microscopy, one morphological type of sarcocysts was observed. Sarcocysts were microscopic, thread-like, had a smooth and thin (about 1 µm) cyst wall and were filled with banana-shaped bradyzoites. On the basis of ITS1 sequences, four Sarcocystis species, S. columbae, S. halieti, S. lari and S. wobeseri, were identified. Furthermore, it was demonstrated that a single infected herring gull could host two Sarcocystis species indistinguishable under light microscopy. Conclusions Larus argentatus is the first bird species found to act as intermediate host of four Sarcocystis spp. According to current knowledge, five species, S. falcatula, S. calchasi, S. wobeseri, S. columbae and S. halieti can use birds belonging to different orders as intermediate hosts.

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Herring Gull (Larus argentatus)

10.2173/bna.hergul.03 ◽

2017 ◽

Cited By ~ 6

Author(s):

Ian C. T. Nisbet ◽

D. V. Weseloh ◽

Craig E. Hebert ◽

Mark L. Mallory ◽

Alan F. Poole ◽

...

Keyword(s):

Larus Argentatus ◽

Herring Gull

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Multivariate Abundance Analysis of Multi-Host/Multi-Parasite Lungworms in a Sympatric Wild Ruminant Population

Diversity ◽

10.3390/d13060227 ◽

2021 ◽

Vol 13 (6) ◽

pp. 227

Author(s):

Tessa Carrau ◽

Carlos Martínez-Carrasco ◽

María Magdalena Garijo ◽

Francisco Alonso ◽

Rocío Ruiz de Ybáñez ◽

...

Keyword(s):

Population Level ◽

Parasite Load ◽

Fallow Deer ◽

Host Population ◽

Marginal Effect ◽

Wild Ruminant ◽

Additional Species ◽

Parasite Abundance ◽

Associated Risk Factors ◽

Natural Dynamics

In the analysis of a multi-host/multi-parasite system and its associated risk factors, it is particularly interesting to understand the natural dynamics among pathogens, their hosts, and the environment in wildlife populations. This analysis is particularly feasible in a scenario where multiple overlapping host populations are present in high densities, along with a complex community of parasites. We aimed to describe and analyze the naturally occurring lungworm polyparasitism in a wild ruminant community in Southeast Spain. The respiratory tracts of 250 specimens belonging to four different species (red deer, mouflon, Iberian ibex, and fallow deer) were studied. Almost half (48.0%) of the animals were infected with bronchopulmonary nematodes. Seven different nematodes were identified of which two genera (Protostrongylus spp. and Dictyocaulus spp.) and three additional species (Cystocaulus ocreatus, Muellerius capillaris, and Neostrongylus linearis) were recorded in at least two ruminants, with the mouflon as the commonest host. Our study shows a significant effect of host species and sampling area, plus a marginal effect of age, on parasite multivariate abundance at the host population level. Mouflon and adults of all hosts appear to carry the highest parasite load on average. From a spatial perspective, the highest parasite abundance was detected at the central part of the park.

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Residues of DDE and PCB in Eggs from Herring Gull (Larus Argentatus) and Common Gull (Larus Canus) in Norway

Acta Veterinaria Scandinavica ◽

10.1186/bf03547741 ◽

1971 ◽

Vol 12 (3) ◽

pp. 429-441

Author(s):

John Erik Bjerk ◽

Gunnar Holt

Keyword(s):

Larus Argentatus ◽

Herring Gull

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Do different parasite species interact in their effects on host fitness? A case study on parasites of the amphipod Paracalliope fluviatilis

Parasitology ◽

10.1017/s0031182011000928 ◽

2011 ◽

Vol 138 (9) ◽

pp. 1176-1182 ◽

Cited By ~ 16

Author(s):

C. A. RAUQUE ◽

R. A. PATERSON ◽

R. POULIN ◽

D. M. TOMPKINS

Keyword(s):

Parasite Species ◽

Low Frequency ◽

Host Population ◽

Interactive Effects ◽

Population Means ◽

Significant Relationships ◽

Coitocaecum Parvum ◽

Paracalliope Fluviatilis ◽

Generally True

SUMMARYThere is a gap in our understanding of the relative and interactive effects of different parasite species on the same host population. Here we examine the effects of the acanthocephalan Acanthocephalus galaxii, an unidentified cyclophyllidean cestode, and the trematodes Coitocaecum parvum and Microphallus sp. on several fitness components of the amphipod Paracalliope fluviatilis, using a combination of infection surveys and both survival and behavioural trials. In addition to significant relationships between specific parasites and measures of amphipod survival, maturity, mating success and behaviour, interactions between parasite species with respect to amphipod photophilia were also significant. While infection by either A. galaxii or C. parvum was associated with increased photophilia, such increases were negated by co-infection with Microphallus sp. We hypothesize that this is due to the more subtle manipulative effect of A. galaxii and C. parvum being impaired by Microphallus sp. We conclude that the low frequency at which such double infections occur in our sampled population means that such interactions are unlikely to be important beyond the scale of the host individual. Whether or not this is generally true, implying that parasitological models and theory based on single parasite species studies do generally hold, requires cross-species meta-analytical studies.

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Temporal and geographic variation of organochlorine residues in eggs of the common snapping turtle (Chelydra serpentina serpentina) (1981–1991) and comparisons to trends in the herring gull (Larus argentatus) in the Great Lakes basin in Ontario, Canada

Archives of Environmental Contamination and Toxicology ◽

10.1007/bf00212435 ◽

1996 ◽

Vol 31 (4) ◽

pp. 512-524 ◽

Cited By ~ 27

Author(s):

C. A. Bishop ◽

P. Ng ◽

R. J. Norstrom ◽

R. J. Brooks ◽

K. E. Pettit

Keyword(s):

Great Lakes ◽

Geographic Variation ◽

Larus Argentatus ◽

Herring Gull ◽

Chelydra Serpentina ◽

Great Lakes Basin ◽

Snapping Turtle ◽

The Common

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The herring gull Larus argentatus as a likely transmitting agent of Salmonella montevideo to sheep and cattle

Journal of Hygiene ◽

10.1017/s0022172400060472 ◽

1983 ◽

Vol 91 (3) ◽

pp. 437-443 ◽

Cited By ~ 33

Author(s):

J. C. Coulson ◽

J. Butterfield ◽

C. Thomas

Keyword(s):

Geographical Distribution ◽

Feeding Behaviour ◽

Circumstantial Evidence ◽

Larus Argentatus ◽

Herring Gull ◽

Breeding Area ◽

Original Source ◽

Herring Gulls ◽

Wintering Area

SUMMARYThis paper presents evidence for the involvement of herring gulls (Larus argentatus) as vectors in the recent outbreaks of Salmonella montevideo in sheep and cattle in Scotland and suggests that the transfer can take place over considerable distances. The breeding area in Scotland of herring gulls which overwinter in N.E. England is remarkably similar to the geographical distribution of the outbreaks. This pattern, together with the feeding behaviour of herring gulls on farmland, the presence of S. montevideo in herring gulls just before their departure from the wintering area and the timing of the return just before the peak of outbreaks are all circumstantial evidence implicating this gull in the outbreaks. The rapid return of these gulls to their breeding areas means that S. montevideo can be transported long distances in one day and raises the possibility that the original source of S. montevideo could have been in N. E. England rather than in Scotland.

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