Intestinal helminth fauna of striped dolphins (Stenella coeruleoalba) in the western Mediterranean: No effects of host body length, age and sex

Abstract Background Current data about Pseudaliidae show contrasting patterns of host specificity between congeneric species. We investigated how both contact and compatibility between hosts and parasites contributed to the patterns of lungworm infection observed in a community of five species of cetaceans in the western Mediterranean. Methods The lungs of 119 striped dolphins Stenella coeruleoalba, 18 bottlenose dolphins Tursiops truncatus, 7 Risso’s dolphins Grampus griseus, 7 long-finned pilot whales Globicephala melas, and 6 common dolphins Delphinus delphis were analysed for lungworms. Parasites were identified by morphology and analysis of ITS2 sequences using both maximum likelihood and Bayesian inference methods. Body length was used as a proxy for lungworm species fitness in different hosts and compared with Kruskal-Wallis tests. Infection parameters were compared between cetacean species using Fisher’s exact tests and Kruskal-Wallis tests. Phylogenetic specificity was explored by collating the overall lungworm species prevalence values in hosts from previous surveys in various localities. To explore the relative importance of vertical and horizontal transmission, Spearman’s rank correlation was used to look for an association between host size and lungworm burden. A Mantel test was used to explore the association between lungworm species similarity and prey overlap using dietary data. Results Halocercus delphini had higher infection levels in striped dolphins and common dolphins; Stenurus ovatus had higher infection levels in bottlenose dolphins; and Stenurus globicephalae had higher infection levels in long-finned pilot whales. These results are congruent with findings on a global scale. Morphometric comparison showed that the larger nematodes were found in the same host species that had the highest parasite burden. Lungworms were found in neonatal striped dolphins and a Risso’s dolphin, and there was a weak but significant correlation between host size and parasite burden in striped dolphins and bottlenose dolphins. There was also a weak but significant association between prey overlap and lungworm species similarity. Conclusions Data indicate that phylogenetic specificity has an important role in governing host–parasite associations, as indicated by the higher infection levels and larger nematode size in certain hosts. However, diet can also influence infection patterns in these preferred hosts and contribute to less severe infections in other hosts.

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Distribution of larval anisakids in blue whiting off Portuguese fish market

Helminthologia ◽

10.2478/s11687-006-0051-8 ◽

2007 ◽

Vol 44 (1) ◽

pp. 21-24 ◽

Cited By ~ 15

Author(s):

C. Cruz ◽

C. Barbosa ◽

A. Saraiva

Keyword(s):

Body Length ◽

Body Cavity ◽

Mean Intensity ◽

Blue Whiting ◽

Host Body ◽

Fish Market

AbstractSpecimens of Micromesistius poutassou (n=238) obtained in a fish market of Oporto, Portugal, were examined for the presence of larval anisakids. Anisakis sp. L3 larvae (prevalence = 77.7 %; mean intensity = 5.8; mean abundance = 4.5) and Hysterothylacium sp. L3 larvae (prevalence = 5 %; mean intensity = 4.1; mean abundance = 0.2) were found in body cavity, mesenteries, liver and muscles. The Anisakis sp. intensity and abundance were significantly related to the host body length. The percentage of Anisakis sp. in muscle was inversely related to the host length.

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Food of striped dolphin, Stenella coeruleoalba, in the Ligurian Sea

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400033117 ◽

1993 ◽

Vol 73 (3) ◽

pp. 571-578 ◽

Cited By ~ 40

Author(s):

M. Würtz ◽

D. Marrale

Keyword(s):

Mediterranean Sea ◽

Western Mediterranean ◽

Important Food ◽

Ligurian Sea ◽

Stenella Coeruleoalba ◽

Striped Dolphin ◽

Western Mediterranean Sea ◽

Bony Fishes ◽

Food Species ◽

Ligurian Coast

The stomachsof 23 striped dolphins (Stenella coeruleoalba Meyen, 1833, Cetacea), stranded along the Ligurian coast (western Mediterranean Sea), contained 32 species of cephalopods, crustaceans and fishes, totalling an estimated 2,723 prey specimens representing about 36 kg in weight. Cephalopods and bony fishes were equally important in the diet (50%). Todarodes sagittatus (34.5%) and Micromesistius poutassou (25.9%) were found to be the most important food species. Other species belonging to six cephalopod families, three crustacean families and nine bony fish families, contributed to the diet with variable numbers, weights, and occurrences, demonstrating the opportunistic character of striped dolphin feeding.

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Microtriches of tetraphyllidean metacestodes from Western Mediterranean striped dolphins (Stenella coeruleoalba)

Journal of Morphology ◽

10.1002/jmor.10349 ◽

2005 ◽

Vol 265 (2) ◽

pp. 176-189 ◽

Cited By ~ 2

Author(s):

Celia Agustí ◽

Francisco Javier Aznar ◽

Juan Antonio Raga

Keyword(s):

Western Mediterranean ◽

Stenella Coeruleoalba

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Intestinal helminth parasites of the ray Raja naevus in British waters

Journal of Helminthology ◽

10.1017/s0022149x00007215 ◽

1977 ◽

Vol 51 (1) ◽

pp. 11-21 ◽

Cited By ~ 10

Author(s):

A. H. McVicar

Keyword(s):

Species Composition ◽

Significant Variation ◽

Nematode Species ◽

Life Cycles ◽

Helminth Fauna ◽

Intestinal Helminth ◽

Helminth Parasites ◽

Geographical Differences ◽

Host Sex ◽

Host Diet

ABSTRACTFive cestode, one monogenean, and two nematode species comprised the “normal” intestinal helminth fauna of Raja naevus in British waters. An additional two nematodes, a digenean, an acanthocephalan and a crustacean recorded are considered to be accidental infections. Geographical differences in the species composition and level of infection are noted and discussed. Short descriptions of the tetraphyllidean cestode Echeneibothrium sp. and the nematode Capillaria sp. are given, but the species, although probably both new, are left unnamed. The intensity of cestode infections show two patterns associated with host length and these are discussed in relation to variations in host diet. Speculations are made on the cestode life cycles. Only Echeneibothrium sp. numbers showed any significant variation associated with host sex.

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Morphological and molecular characterization of tetraphyllidean merocercoids (Platyhelminthes: Cestoda) of striped dolphins (Stenella coeruleoalba) from the Western Mediterranean

Parasitology ◽

10.1017/s0031182004006754 ◽

2004 ◽

Vol 130 (4) ◽

pp. 461-474 ◽

Cited By ~ 29

Author(s):

C. AGUSTÍ ◽

F. J. AZNAR ◽

P. D. OLSON ◽

D. T. J. LITTLEWOOD ◽

A. KOSTADINOVA ◽

...

Keyword(s):

Large Subunit ◽

Variable Region ◽

Single Species ◽

Western Mediterranean ◽

Apical Organ ◽

Morphological Data ◽

Histological Techniques ◽

Stenella Coeruleoalba ◽

Low Degree ◽

First Time

Two types of tetraphyllidean merocercoids, Phyllobothrium delphini and Monorygma grimaldii, are well known from most cetaceans world-wide. The role of cetaceans in the life-cycle of these merocercoids is unclear because their specific identity is as yet unknown. The problem is compounded by poor descriptions of both merocercoids. We used light and scanning electron microscopy, and histological techniques to provide a thorough description of merocercoids collected from 11 striped dolphins, Stenella coeruleoalba, from the Spanish Mediterranean. We also described, for the first time, specimens of P. delphini with immature proglottides. Our merocercoids were morphologically similar to those described previously, except in the structure of the apical organ. Intra- and inter-sample variability in the morphology of the apical organ suggested that it degenerates during larval development. A subsample of 16 specimens of P. delphini and M. grimaldii was characterized for the D2 variable region of the large subunit ribosomal RNA gene (LSU) and compared with published tetraphyllidean cestode LSU sequences. P. delphini showed 2 unique signatures that differed from one another by a single base, whereas all sequences of M. grimaldii were identical. This suggests that each type may represent a single species, contrary to previous speculations based on morphological data. All merocercoid specimens formed a clade together with Clistobothrium montaukensis. Based on the low degree of divergence, all specimens of this clade are predicted to be congeneric.

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