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1.
The taxonomy of marine species of the genus Diphyllobothrium, particularly those parasitic in cetaceans, is rather confused. During parasitological investigations of long-finned pilot whales Globicephala melas from waters off the Faroe Islands, five diphyllobothriid species were detected: Diphyllobothrium sp. (possibly D. polyrugosum), D. stemmacephalum, Diphyllobothrium sp. A, Diphyllobothrium sp. B and Diphyllobothriidae sp. D. stemmacephalum is reported for the first time from G. melas. The stituation regarding the taxonomy of Diphylobothrium species from cetaceans is briefly reviewed. It is concluded that the recent development of genetic techniques may be of great value in relation to clarifying the taxonomy of this group.  相似文献   

2.
In November, 1968, a single specimen ofPhaneropsolus macacae (Premvati, 1958)Saoud, 1964 was collected from the small intestine of a female Taiwanese monkey,Macaca cyclopis (Swinhoe, 1862). The Taiwanese monkey was added as a new host for this trematode.  相似文献   

3.
The widely distributed long-finned pilot whale (Globicephala melas) has been reported off the Chilean coast, from Iquique (20°12′S) south to Navarino Island (55°15′S; 67°30′W), but little is known about its biology or ecology in the region. Here, we report on the prey of this species, identified by stomach content analyses from animals stranded on Holget Islets, Beagle Channel, southern Chile in August 2006. The stomachs of seven individuals (six females and one male) contained cephalopod remains. The prey composition found in these southern Chilean pilot whales was similar to that described in other parts of the world and the Southern Ocean. This is the first report on the feeding habits of this species from Chile.  相似文献   

4.
Ten prey taxa were recorded from the stomach contents of eight long-finned pilot whales ( Globicepbala melas ) independently stranded along the U.S. mid-Atlantic coast. Relative importance of prey species was determined by methods that incorporate prey frequencies of occurrence, proportions of numerical abundance, and proportions of reconstructed mass. Separate analyses of trace (free, durable body parts representing well-digested prey items) and non-trace (relatively intact prey specimens) food material were conducted in order to address biases caused by differential rates of digestion and passage through the gastrointestinal tract. Different measures of prey importance yielded varying results, but the long-finned squid ( Loligo pealei ) was the most important prey species regardless of how prey importance was defined. Fishes were relatively unimportant in the diet. Our results indicate that the diets of western North Atlantic long-finned pilot whales differ substantially from what has been previously reported in the literature and that results from food-habits studies that utilize different techniques may not be comparable.  相似文献   

5.
Two ecotypes of the common bottlenose dolphin (Tursiops truncatus) occur in New Zealand waters: a widely studied Nationally Endangered coastal ecotype and a little-known oceanic ecotype. Site fidelity and association patterns of the oceanic ecotype, and home range overlap with the coastal ecotype, are examined from photo-identification records collected off northeastern New Zealand between 2005 and 2016. The oceanic ecotype occurs widely in the study area: distance from shore ranged from <1 to ~150 km and home ranges of the two ecotypes overlap in some areas. Forty-nine percent of the 478 identified distinctive or very distinctive individuals were sighted during more than 1 year and resightings spanned over 10 years and 650 km. All individuals were linked by association in a single, albeit clustered, social network. Unlike the coastal ecotype, interspecific associations with false killer (Pseudorca crassidens) and southern long-finned pilot whales (Globicephala melas edwardii) were frequent, occurring during 84% of encounters. Only one oceanic individual matched any of the individuals from the coastal ecotype photo-identification catalogues throughout the study area, suggesting that the two ecotypes co-occur parapatrically. We recommend that the two ecotypes be considered independent management units for conservation purposes due to their divergent ecologies.  相似文献   

6.
7.
From samples collected in the Caribbean Sea during February, March, May and August 1991, a total of 22 508 holoplanktonic chaetognaths were caught. During the analyses of the samples, one non-cysted specimen of didymozoid metacercaria was found in the coelom of the chaetognath Serratosagitta serratodentata (prevalence 0.004%). Owing to the lack of an authentic stomach and the morphology of the intestine, this trematode seems to belong to the Torticaecum larval type. This is the first report of both the chaetognath species as a host and the geographical locality for this parasite.   相似文献   

8.
We report evidence of enzootic morbillivirus infection among long-finned, Globicephala melas, and short-finned, G. macrorhynchus, pilot whales in the western Atlantic. A retrospective serologic survey, using five morbilliviruses, was carried out on 99 G. melas from 14 stranding events between 1982 and 1993 and from 25 G. macrorhynchus stranded in 5 events between 1986 and 1994. A blood sample was also obtained from an adult G. melas by-caught in the western North Atlantic. Tissues were collected from 24 G. melas and 15 G. macrorhynchus for histology and immunoperoxidase staining. Neutralizing antibody titers were found in 92 (92%) of 100 G. melas and 16 (64%) of 25 G. macrorynchus, and titers were highest against cetacean morbilliviruses. Seroprevalence was similar between age classes and sexes. The earliest evidence of infection was in a G. melas that stranded in 1982. Stable antibody titers were observed in pilot whales under rehabilitation for up to eight months. Clinical disease consistent with morbillivirus pneumonia was detected in a G. melas calf. Immunoperoxidase staining confirmed that viral antigen was present in the lesions. We propose that enzootic infection in pilot whales is facilitated by population size, social structure, and migration patterns. Furthermore, through mixing with other odontocetes, pilot whales could act as vectors through the Atlantic. Clinical morbillivirus infection may precipitate mass strandings of highly social odontocetes.  相似文献   

9.
Three species of cyprinids, i.e., Capoeta antalyensis (n = 112), C. caelestis (n = 99) and C. angorae (n = 178) were collected from the Anatolian Region of Turkey to carry out this investigation. A total of 389 specimens of Capoeta were examined for Allocreadium isoporum infections throughout the four different seasons of 2012. The prevalence and mean intensity of infection of A. isoporum was investigated in relation to the host species, the seasons across the year, host size, and sex. Two‐hundred and twenty‐two specimens of a trematode identified as A. isoporum were found in these fishes. One‐hundred seventy‐eight C. angorae were caught, and 70 A. isoporum were recorded in 8 of 178 fish examined, with prevalence and mean intensity of infection of 4.49% and 8.7% parasites per infected fish, respectively. In the 112 specimens of C. antalyensis, 73 individuals of A. isoporum were found, with a prevalence of 19.6% and a mean intensity of 3.3. As for the infection in C. caelestis, a total of 79 specimens of A. isoporum were found in 17 of the 99 fish examined, with prevalence and mean intensity of infection of 17.1% and 4.6%, respectively. Prevalence and mean intensity values in relation to host size and sex, as well as the seasonality of infections was analyzed and the results were compared with other studies. The trematode A. isoporum is reported for the first time parasitising three endemic species of Capoeta spp. in Turkey, adding to the knowledge of geographical distribution and host range of this trematode species.  相似文献   

10.
The chemical nature and mode of stabilization of egg-shell protein in digenetic trematode Helicometra pulchella (Rudolphi, 1819) have been investigated using histochemical techniques. It was found that the egg-shell is stabilized by quinone-tanning together with dityrosine. Other structural proteins (elastin, collagen and keratin-like proteins), glycogen and acid mucopolysaccharides were absent in egg-shell. Tyrosine was present in vitelline cells and immature egg-shell indicating that the proteins involved in quinone-tanning were tyrosine rich and tyrosyl residues are modified to form dityrosine in mature egg-shell.  相似文献   

11.
Determining how intra-specific genetic diversity is apportioned among natural populations is essential for detecting local adaptation and identifying populations with inherently low levels of extant diversity which may become a conservation concern. Sequence polymorphism at two adaptive loci (MHC DRA and DQB) was investigated in long-finned pilot whales (Globicephala melas) from four regions in the North Atlantic and compared with previous data from New Zealand (South Pacific). Three alleles were resolved at each locus, with trans-species allele sharing and higher levels of non-synonymous to synonymous substitution, especially in the DQB locus. Overall nucleotide diversities of 0.49?±?0.38% and 4.60?±?2.39% were identified for the DRA and DQB loci, respectively, which are relatively low for MHC loci in the North Atlantic, but comparable to levels previously described in New Zealand (South Pacific). There were significant differences in allele frequencies within the North Atlantic and between the North Atlantic and New Zealand. Patterns of diversity and divergence are consistent with the long-term effects of balancing selection operating on the MHC loci, potentially mediated through the effects of host-parasite coevolution. Differences in allele frequency may reflect variation in pathogen communities, coupled with the effects of differential drift and gene flow.  相似文献   

12.
The reproductive cycle and parasitism in the clam Anomalocardia brasiliana were studied in two different areas, an intermediate beach (Cidade) and a tidal flat (Araçá), in Southeast Brazil. Four gametogenic stages were described for males and females in both areas. Mature and spawning individuals were present throughout the period of study at Cidade and Araçá; however, major temporal differences were recorded between sites. Whereas only a few individuals in the resting stage were recorded at Cidade throughout the study period, resting stage individuals were frequent at Araçá. Moreover, a shorter period of gametogenesis was observed at Araçá than at Cidade. Oocyte number was the most effective parameter to differentiate gametogenic stages. An unidentified digenetic trematode was the only parasite infecting A. brasiliana at the study sites, and caused castration of all hosts. Parasite prevalence (proportion of infected hosts) was similar and low (ca 7.5%) at Cidade and Araçá and therefore is not expected to compromise the reproductive output of these populations. Comparison with data from previous studies suggests a latitudinal pattern for the reproductive biology of A. brasiliana, with resting stages occurring only at two high-latitude sites; however, no evidence was found for a latitudinal pattern of trematode prevalence in this species.  相似文献   

13.
A new species, Gonapodasmius epinepheli (Didymozoidae: Gonapodasmiinae), is described from the fish Epinephelus tauvina from the Arabian Gulf. It differs from most other members of the genus in the presence of a bulbous swelling at the distal end of the ovary, the presence of a characteristic bulge in the genital junction region, in the dense mass of glandular cells around the intestinal limbs and in the presence of an empty metraterm and vas deferens in the male and female respectively. The new species represents the first record of a didymozoid trematode from fishes in the Arabian Gulf.  相似文献   

14.
Foote AD 《Biology letters》2008,4(2):189-191
The strength of selection to increase the span of a life stage is dependent upon individuals at that stage being able to contribute towards individual fitness and the probability of their surviving to that stage. Complete reproductive cessation and a long post-reproductive female lifespan as found in humans are also found in killer whale (Orcinus orca) and short-finned pilot whale (Globicephala macrorhynchus), but not in the long-finned pilot whale (Globicephala melaena). Each species forms kin-based, stable matrilineal groups and exhibits kin-directed behaviours that could increase inclusive fitness. Here, the initial mortality rate and mortality rate-doubling time of females of these three closely related whale species are compared. The initial mortality rate shows little variation among pilot whale species; however mortality rate accelerates almost twice as fast in the long-finned pilot whale as it does in killer whale and short-finned pilot whale. Selection for a long post-reproductive female lifespan in matrilineal whales may therefore be determined by the proportion of females surviving past the point of reproductive cessation.  相似文献   

15.
Nine polymorphic microsatellite loci were characterized from the freshwater trematode Coitocaecum parvum. This parasite can either reproduce sexually in the definitive host or produce eggs by selfing inside its second intermediate host. Two to 11 alleles per locus were detected in 24 trematode sporocysts and observed heterozygosities ranged from 0.04 to 0.96. These loci will be useful for identifying parasite genetic clones within hosts and testing for effects of relatedness on parasite life history strategy.  相似文献   

16.

A new cryptogonimid trematode, Siphoderina hustoni n. sp., is reported, collected off Lizard Island, Queensland, Australia, from the Maori snapper Lutjanus rivulatus (Cuvier). The new species is moderately distinctive within the genus. It is larger and more elongate than most other species of Siphoderina Manter, 1934, has the shortest forebody of any, a relatively large ventral sucker, a long post-testicular zone, and is perhaps most recognisable for the substantial space in the midbody between the ventral sucker and ovary devoid of uterine coils and vitelline follicles, the former being restricted to largely posterior to the ovary and the latter distributed from the level of the anterior testis to the level of the ovary. In phylogenetic analyses of 28S ribosomal DNA, the new species resolved with the other nine species of Siphoderina for which sequence data are available, all of which are from Queensland waters and from lutjanid and haemulid fishes. Molecular barcode data were also generated, for the ITS2 ribosomal DNA and cox1 mitochondrial DNA markers. The new species is the first cryptogonimid known from L. rivulatus and the first metazoan parasite reported from that fish in Australian waters.

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17.
In November 2007, a 46-year-old male Thai patient presented with chronic abdominal pain for over 3 years. Colonoscopy revealed a small parasite of about 2 × 1 mm in size attached to the cecum mucosa. The worm was removed endoscopically, fixed, and stained for morphological observations. The specimen was identified as Anchitrema sanguineum (Digenea: Anchitrematidae), a trematode first reported in a reptile, Chamaeleo vulgaris, from Egypt, and then sporadically found in the intestines of insectivorous bats and other mammals. The patient was treated with praziquantel but no more worms were found in his stool. His symptoms improved slightly but not cured completely. It remains unclear whether the chronic abdominal pain of the patient was caused by this trematode infection. Whatever is the pathogenicity of this trematode, this is the first human case of A. sanguineum infection in the literature.  相似文献   

18.
A new trematode genus, Grammatorcynicola n. g. (Bucephalidae: Dolichoenterinae), and two new species, G. brayi n. sp. and G. nolani n. sp. from the intestines of the scombrids, Grammatorcynus bicarinatus and Gr. bilineatus respectively, are reported from the Great Barrier Reef, Australia. Grammatorcynicola n. g. is placed in the Dolichoenterinae, as the pharynx is in the anterior quarter of the body, the caecum is tube-like and extends to the posterior quarter of the body, the cirrus-sac is small relative to the size of the worm when compared with other bucephalids and the pars prostatica is curved. Grammatorcynicola n. g. differs from other dolichoenterine genera in having a simple sucker-like rhynchus, the ovary anterior to the testes and by not having a particularly thick cirrus-sac wall.  相似文献   

19.
A preliminary study of the gill parasites from 61 common dentex (Dentex dentex, Pisces, Sparidae) was developed. Seven parasite species were found: one monogenean (Microcotyle erythrini), one udonellidean Udonella caligorum), one digenean trematode (Stephanostomum sp. metacercariae), three copepods (Caligus productus, Caligus diaphanus and Clavellopsis fallax) and one isopod (Gnathia vorax, praniza larvae). Only 1.6% of the fishes examined presented one parasitic species whilst the remainder had two parasitic species (13%), three (26%), four (21%), five (20%) and six different species (18%). The udonellidean U. caligorum was found as a hyperparasite or phoront of the three copepods. Prevalence and other ecological parameters as well as the spatial site of each parasite in the gill tissue are described. The multiparasitic combinations are also examined.  相似文献   

20.
Grass shrimp, Palaemonetes pugio Holthuis and P. vilgaris (Say), were collected at 11 localities along the coast of Georgia and surveyed for digenetic trematode metacercariae. The effect of trematode infection on grass shrimp fitness was also examined. Microphallus turgidas (Leigh) was the only trematode observed. The prevalence of metacercarial cysts of this parasite in P. pugio (75%) was higher than in P. vulgaris (24%), as were the mean intensity, abundance, and population density (no. cysts/cm host body length) of the parasite. Infected shrimp were found at every collection locality and parasite prevalence and density were greatest in P. pugio from higher salinity localities (> or = 20 parts per thousand [ppt]). There was no relation between host body size and parasite density in P. vulgaris, and parasite density increased with host body size in P. pugio, suggesting that the parasite does not affect host survival. There was no relation between parasite density and shrimp egg mass, but nonovigerous female P. pugio were more heavily infected than ovigerous ones. In addition, 1 metacercaria of M. turgidus in each of 2 specimens of P. vulgaris was parasitized by the haplosporidian Urosporidium crescens De Turk. This represents a new shrimp host record for this hyperparasite.  相似文献   

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