Experimental transmission of Otostrongylus circumlitus (Railliet, 1899) (Metastrongyloidea: Crenosomatidae), a lungworm of seals in eastern arctic Canada

1997 ◽  
Vol 75 (9) ◽  
pp. 1364-1371 ◽  
Author(s):  
Emmanuelle Bergeron ◽  
Jean Huot ◽  
Lena N. Measures

The transmission of few metastrongyloids infesting marine mammals is known. The results of experimental infections using Otostrongylus circumlitus (Crenosomatidae), a lungworm of pinnipeds, suggested that this metastrongyloid uses fish as intermediate hosts. Various marine organisms (crustaceans, molluscs, and fish) were exposed to first-stage larvae from naturally infected young-of-the-year ringed seals (Phoca hispida) from northern Quebec (Salluit). The first and second moults occurred 3 and 56 days post exposure in the mucosa and muscularis of the intestine of American plaice (Hippoglossoides platessoides) kept at 4 °C. Third-stage larvae were found under the intestinal serosa. Attempts to infect invertebrates were unsuccessful. Transmission to seals may occur from mid-June through the autumn as young seals start feeding intensively on invertebrates and fish. First-stage larvae leave the lungs via the bronchial escalator and are swallowed and released into the sea with the faeces of seals, where they would be available to benthic or pelagic fish. The morphology of the first three larval stages is described.

Parasitology ◽  
2007 ◽  
Vol 134 (11) ◽  
pp. 1541-1550 ◽  
Author(s):  
N. CARRASCO ◽  
I. LÓPEZ-FLORES ◽  
M. ALCARAZ ◽  
M. D. FURONES ◽  
F. C. J. BERTHE ◽  
...  

SUMMARYSince the first description of Marteilia refringens (Paramyxea) in flat oysters Ostrea edulis in 1968 in the Aber Wrach, Brittany (France), the life-cycle of this parasite has remained unknown. However, recent studies, conducted in the ‘claire’ system, have proposed the planktonic copepod Acartia grani as a potential intermediate host for the parasite. Nevertheless, experimental transmission of the parasite through the copepod has failed. Recent studies in this field have reported the presence of the parasite in zooplankton from the bays of the Delta de l'Ebre, a more complex and natural estuarine environment than that of the claire. As a result, 2 new Marteilia host species were proposed: the copepods Oithona sp. (Cyclopoida) and an indeterminate Harpaticoida. Consequently, the objective of the present work was to study the dynamics of Marteilia in the zooplankton community from one of the bays, Alfacs Bay, as well as the dynamics of the parasite in cultivated mussels during 1 complete year. Six different zooplankton taxa appeared to be parasitized by M. refringens, including copepods (3 Calanoida, Acartia discaudata, A. clausi and A. italica; 1 Cyclopoida, Oithona sp.; and 1 Harpacticoida, Euterpina acutifrons), and larval stages of decapod crustaceans (zoea larvae of Brachyura, probably Portumnus sp.). These taxa are thus proposed as new subjects for study, since they could be intermediate hosts in the infection process of mussels by Marteilia.


1998 ◽  
Vol 76 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Murray W Lankester ◽  
Ing-Marie C Olsson ◽  
Margareta Stéen ◽  
Alvin A Gajadhar

Dimensions and illustrations of the first-, second-, and third-stage larvae of Elaphostrongylus alces are presented for the first time. First-stage larvae were 417 ± 16 µm long (mean ± SD) (range 377-445 µm) and similar in size to those of E. cervi (420 ± 13 µm long; range 392-445 µm) and E. rangiferi, the other recognized members of the genus. The mean length of third-stage E. alces larvae (714 ± 23 µm long; range 675-756 µm) recovered from gastropod intermediate hosts was significantly less than that of E. cervi (831 ± 78 µm long; range 669-954 µm) and E. rangiferi, providing further evidence of the distinct status of E. alces, a recently described species from moose in Fennoscandia.


1997 ◽  
Vol 54 (10) ◽  
pp. 2443-2448 ◽  
Author(s):  
E Bergeron ◽  
L N Measures ◽  
J Huot

Otostrongylus circumlitus, a metastrongyloid nematode found in the lungs of ringed seals (Phoca hispida) and other pinnipeds, may affect the health of seals and reduce diving capacity. Of five sites sampled in eastern Arctic Canada (190 seals examined), Salluit, Que., is an important enzootic zone (prevalence 48.2%, n = 27). Maximum intensity of O. circumlitus was 32 worms. Infection is restricted to young-of-the-year seals and may have an impact on recruitment of the population. Local geographic conditions may influence transmission of the parasite and thus prevalence and intensity of O. circumlitus among populations of ringed seals. No condition index used showed any significant relationship to infection, but prevalence and intensity were related to sternal blubber thickness (0.01 < p < 0.05) indicating that this parasite may have an effect on the physical condition of seals. Otostrongylus circumlitus may have an indirect effect on seals by modifying their diving behavior. Severe infections may lead to death, but light infections could be lost after a certain time with subsequent development of protective immunity.


1962 ◽  
Vol 40 (7) ◽  
pp. 1175-1186 ◽  
Author(s):  
Roy C. Anderson

Eggs of Diplotriaena bargusinica from worms found in a Hylocichla fuscescens from Algonquin Park, Ontario, hatched and developed in the fat body of grasshoppers (Melanoplus bilituratus, M. fasciatus, Camnula pellucida). At approximately 30–33 °C the first molt took place on the 9–11th day, the second on the 14–16th day. Most second- and third-stage larvae were enveloped in capsules, more than one larva often being present in a single capsule. The larval stages from grasshoppers are described. Grasshoppers with infective larvae were fed to two H. fuscescens, one H. ustulata. one Turdus migratorius, and one Quiscalus quiscula. Subadult worms were found in the two H. fuscescens and the H. ustulata 55–301 days later but none was found in the other birds examined 78–97 days later. Late fourth-stage larvae from the heart and aorta of a nestling H. ustulata captured in the field are described. It is believed tridents first make their appearance during development in the definitive host from the infective stage to the fourth stage. Observations on the morphology of adult D. bargusinica are also reported.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
William Robbins ◽  
Gary Conboy ◽  
Spencer Greenwood ◽  
Roland Schaper

Abstract Background Metastrongyloid parasites Angiostrongylus vasorum and Crenosoma vulpis infect wild and domestic canids and are important pathogens in dogs. Recent studies indicate that gastropod intermediate hosts infected with various metastrongyloids spontaneously shed infective third-stage larvae (L3) into the environment via feces and mucus under laboratory conditions. Shed L3 retain motility up to 120 days, but whether they retain infectivity was unknown. Methods To assess the infectivity of shed L3, the heart/lungs of six red foxes (Vulpes vulpes) were obtained from trappers in Newfoundland, Canada. Lungs were examined for first-stage larvae (L1) by the Baermann technique. A high number of viable A. vasorum L1 and a low number of C. vulpis L1 were recovered from one fox; these were used to infect naïve laboratory-raised Limax maximus. L3 recovered from slugs by artificial digestion were fed to two naïve purpose-bred research beagles (100 L3/dog). L1 shed by these two dogs was used to infect 546 L. maximus (2000–10,000 L1/slug). L3 shedding was induced by anesthetizing slugs in soda water and transferring them into warm (45 °C) tap water for at least 8 h. Shed L3 recovered from slugs were aliquoted on romaine lettuce in six-well tissue culture plates (80–500 L3/well) and stored at 16 °C/75% relative humidity. Four naïve research beagles were then exposed to 100 L3/dog from larvae stored for 0, 2, 4, or 8 weeks, respectively, after shedding. Results All four dogs began shedding C. vulpis L1 by 26–36 days post-infection (PI). All four dogs began shedding A. vasorum L1 by 50 days PI. Conclusions L3 infectivity for the definitive host was retained in both metastrongyloids, indicating the potential for natural infection in dogs through exposure from environmental contamination. As an additional exposure route, eating or licking plant or other material(s) contaminated with metastrongyloid L3 could dramatically increase the number of dogs at risk of infection from these parasites. Graphic Abstract


Parasitology ◽  
1946 ◽  
Vol 37 (3-4) ◽  
pp. 192-201 ◽  
Author(s):  
J. F. A. Sprent

A description is given of the processes of copulation, formation of the egg and spermatozoon, cleavage, embryogeny and hatching in B. phlebotomum. These processes were found to be essentially similar to those in other strongyle nematodes.The anatomy of the first three larval stages is described and the observations of Conradi & Barnette (1908) and Schwartz (1924) were largely confirmed.Penetration of the skin of calves by the infective larva was observed histologically. The larvae were found to have reached the dermis within 30 min. and to have penetrated the cutaneous blood vessels within 60 min. of application to the skin. The larvae were found in the lung where the third ecdysis was in progress 10 days after penetration of the skin. A description is given of the growth of the third-stage larva in the lung, the changes which take place during the third ecdysis, and the anatomy of the fourth-stage larva.The fourth-stage larvae exsheath in the lungs and travel to the intestine. After a period of growth in which sexual differentiation takes place, the fourth ecdysis occurs and the adult parasite emerges. The time required for the attainment of maturity was found to be somewhere between 30 and 56 days after penetration of the skin.This paper was written at the Ministry of Agriculture and Fisheries Veterinary Laboratories, Wey-bridge, and the writer would like to express his gratitude to the Director, Prof. T. Dalling, also to Dr W. R. Wooldridge, chairman of the Council of the Veterinary Educational Trust for their help and encouragement. The writer's thanks are also due to Dr H. A. Baylis, Prof. R. T. Leiper and Dr E. L. Taylor for their advice and help on technical points, and to Mr R. A. O. Shonekan, African laboratory assistant, for his able co-operation.


2015 ◽  
Vol 52 (3) ◽  
pp. 229-235 ◽  
Author(s):  
E. M. Mbokane ◽  
J. Theron ◽  
W. J. Luus-Powell

Abstract This study provides information on seasonal occurrence of developmental stages of endoparasites infecting three cyprinids in the Nwanedi-Luphephe dams, Limpopo River System. Labeobarbus marequensis (Smith, 1841), Barbus trimaculatus Peters, 1852 and Barbus radiatus Peters, 1853 were investigated seasonally from January 2008 to October 2008. The following larvae of metazoan parasites were collected: Diplostomum sp. from the eyes of L. marequensis and B. trimaculatus; Ornithodiplostomum sp. from the gills of B. trimaculatus; Posthodiplostomum sp. from muscle, skin and fins of B. trimaculatus and B. radiatus; third-stage Contracaecum larvae (L3) from the mesentery fats and on the liver lobes of L. marequensis and B. trimaculatus and gryporynchid cestode larvae from the outer intestinal wall of B. radiatus. All the flukes encountered were metacercariae. Diplostomum sp. and Contracaecum sp. dominated the parasite communities. Their prevalence exhibited seasonal fluctuations with maxima in summer. Factors likely to influence fish infection such as the body size of fish and their condition factors were also briefly considered in this study.


1976 ◽  
Vol 54 (12) ◽  
pp. 2055-2060 ◽  
Author(s):  
A. K. M. Bashirullah ◽  
Benazir Ahmed

The larval development of Camallanus adamsi Bashirullah, 1974 was followed in intermediate hosts, Mesocyclops leuckarti (Claus) and Thermocyclops crassus (Fischer), which were kept at 24 °C and 27 °C (average). The nematode molted twice in the haemocoel of copepods. The first molt occurred 117 h after infection at 24 °C and the second molt after 249 h. At 27 °C, the first and the second molts occurred 72 and 168 h respectively after the infection. Three larval stages are described.


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1757
Author(s):  
Davide Mugetti ◽  
Elena Colombino ◽  
Vasco Menconi ◽  
Fulvio Garibaldi ◽  
Walter Mignone ◽  
...  

The genus Pennella comprises hematophagous parasites of marine aquatic species, including cephalopods, marine mammals, and pelagic fish. Nine species have been officially included in the genus Pennella plus another six species inquirendae. They are most often found in the host’s musculature, without penetrating internal organs. For the present study, 83 hearts from swordfish (Xiphias gladius) caught in the Mediterranean Sea were sampled and immediately fixed in formalin for histopathological analysis. In total, 10 (12.05%) hearts were found to be parasitized by copepods of the genus Pennella. Macroscopically, there was mild-to-severe fibrinous pericarditis with atrial wall thickening and multiple parasitic nodules. Histologically, the parasitic nodules were surrounded by an inflammatory-necrotizing reaction. Parasitic infestation by Pennella spp. is common in pelagic fish and in swordfish, in particular. Here, however, we report atypical cardiac localization. A future area of focus is the evaluation of cardiac Pennella spp. infestation by histopathology and genetic identification of the parasites.


1978 ◽  
Vol 56 (4) ◽  
pp. 688-694 ◽  
Author(s):  
Stephen R. Kearney ◽  
Frederick F. Gilbert

Terrestrial gastropods were collected within the 1220-ha Himsworth Game Preserve in central Ontario during 1974 to determine their abundance and habitat preference. Collections from systematically arranged plots occurred 23 May to 4 June, 6 July to 14 July, and 26 August to 5 September. In all 16 498 gastropods were collected; 4351, in the first, 5622 in the second, and 6525 in the third collection period. Sixteen species were represented with Discus cronkhitei and Zonitoides arboreus accounting for 69.3% of the specimens. Deroceras laeve and Pallifera dorsalis were the most common slugs. Gastropods (excluding slugs) showed a significant preference for mixed forest and a significant aversion to open habitat types during all collection periods. Slugs were significantly less abundant in mixed forest and more abundant in open habitat types during the third collection period.Eight of the 16 species collected (80.1% of the specimens) have previously been identified as intermediate hosts of Parelaphostrongylus tenuis. However, only 19 third-stage larvae of P. tenuis were obtained from the 16450 gastropods digested in pepsin. It is proposed that Zonitoides arboreus in association with Betula papyrifera may be important components in the transmission of P. tenuis to cervids on the Himsworth Game Preserve.


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