The response of Anisakis larvae to freezing

2002 ◽  
Vol 76 (4) ◽  
pp. 363-368 ◽  
Author(s):  
D.A. Wharton ◽  
O. Aalders

AbstractAnisakis third stage larvae utilize a variety of fish as intermediate hosts. Uncooked fish are rendered safe for human consumption by freezing. Larvae freeze by inoculative freezing from the surrounding medium but can survive freezing at temperatures down to -10°C. This ability may be aided by the production of trehalose, which can act as a cryoprotectant, but does not involve recrystallization inhibition. Monitoring of fish freezing in commercial blast freezers and under conditions which simulate those of a domestic freezer, indicate that it can take a long time for all parts of the fish to reach a temperature that will kill the larvae. This, and the moderate freezing tolerance of larvae, emphasizes the need for fish to be frozen at a low enough temperature and for a sufficient time to ensure that fish are safe for consumption.

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


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.


2022 ◽  
Vol 12 ◽  
Author(s):  
Michelle F. O’Brien ◽  
Sarah Pellett

Gastropods (class Gastropoda) form the largest of the classes in the phylum Mollusca and inhabit terrestrial, fresh water and marine environments. A large number of these species are of major conservation importance and are an essential component of ecosystems. Gastropods may be deemed as pests, having a negative impact in horticulture and agriculture, whereas others may be used as a food source for human consumption and therefore are beneficial. Gastropods are susceptible to primary diseases and also act as intermediate hosts for diseases which affect other animals, including humans. The diseases described include two that are notifiable to the World Organisation for Animal Health (OIE): Xenohaliotis californiensis and Abalone viral ganglioneuritis caused by Haliotid herpesvirus-1 (HaHV-1). Research into the diseases of gastropods has often focused on those species that act as intermediate disease hosts, those that are used in research or those cultured for food. In this paper we review the viral, bacterial, fungal, parasitic and miscellaneous conditions that have been reported in gastropods and mention some of the factors that appear to predispose them to disease. The pathogenicity of a number of these conditions has not been fully ascertained and more research is needed into specifying both the etiological agent and significance in some of the diseases reported.


2019 ◽  
Vol 4 (2) ◽  
pp. 232-236
Author(s):  
Irnawati Marsaulina ◽  
Harlem Marpaung

This community service activity aims to increase the ability of fishermen and apply appropriate technology to cultivate Vannamei shrimp in a sustainable manner so that it will improve the welfare of fishermen's families. To achieve the objectives, several stages of activities are carried out, the first stage of the survey is to find out how the fish cultivator fishermen groups carry out their activities. The second stage is the socialization of activities that will be carried out to increase the ability to grow shrimp so that the results in a long time can increase the income (economy) of the fishermen. The third stage is to carry out coaching and counseling related to shrimp farming and can make decisions in the next economic field. This service program is carried out within 6 months. Program targets and outcomes (1). Increased knowledge and skills on appropriate technology in conducting Vannamei shrimp cultivation (2). Increased Vannamei shrimp yields by conducting shrimp culture training using tarpaulins. (3). In the long run, the results of aquaculture increase the economic welfare of the fishermen's family.


Author(s):  
Rafael Lucyk MAURER ◽  
Carlos GRAEFF-TEIXEIRA ◽  
José Willibaldo THOMÉ ◽  
Luís Antônio CHIARADIA ◽  
Hiroko SUGAYA ◽  
...  

Angiostrongylus costaricensis is a nematode parasitic of rodents. Man may become infected by ingestion of the third stage larvae produced within the intermediate hosts, usually slugs from the family Veronicellidae. An epidemiological study carried out in a locality in southern Brazil (western Santa Catarina State) where these slugs are a crop pest and an important vector for A. costaricensis has documented for the first time the natural infection of Deroceras laeve with metastrongylid larvae. This small limacid slug is frequently found amid the folds of vegetable leaves and may be inadvertently ingested. Therefore D. laeve may have an important role in transmission of A. costaricensis to man.


Marine Drugs ◽  
2013 ◽  
Vol 11 (1) ◽  
pp. 233-252 ◽  
Author(s):  
Maria Raposo ◽  
Rui De Morais ◽  
Alcina Bernardo de Morais

Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina), and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS). It goes through the most studied activities of sulphated polysaccharides (sPS) or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review.


1955 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
MJ Mackerras ◽  
DF Sandars

Adult Angiostrongylus cantonensis live in the pulmonary arteries. Unsegmented ova are discharged into the blood stream, and lodge as emboli in the smaller vessels. First-stage larvae break through into the respiratory tract, migrate up the trachea, and eventually pass out of the body in the faeces. Slugs (Agriolimax laevis) act as intermediate hosts. Two moults occur in the slug, and third-stage larvae appear about the 17th day. The larvae remain within the two cast skins until freed in the stomach of the rat by digestion. They then pass quickly along the small intestine as far as the lower ileum, where they leave the gut and become blood-borne. They congregate in the central nervous system, and have been found there 17 hr after ingestion. The anterior portion of the cerebrum is the most favoured site, and here the third moult takes place on the sixth or seventh day and the final one between the 11th and 13th days. Young adults emerge on the surface of the brain from the 12th to 14th day, and spend the next 2 weeks in the subarachnoid space. From the 28th to 31st days they migrate to the lungs via the venous system, passing through the right side of the heart to their definitive site in the pulmonary arteries. The prepatent period in the rat usually lies between 42 and 45 days.


1998 ◽  
Vol 76 (7) ◽  
pp. 1226-1235 ◽  
Author(s):  
Réjean Hays ◽  
Lena N Measures ◽  
Jean Huot

To determine abundance of larval Anisakis simplex in euphausiids of the St. Lawrence estuary, Meganyctiphanes norvegica and Thysanoessa raschii were collected at seven sites from the mouth of the Saguenay River to Baie des Outardes. Larvae were removed from euphausiids by means of a modified Baermann apparatus filled with a pepsin-HCl digest solution. Abundances of larvae in euphausiids ranged from 0 to 58.2 × 10-5. Larvae (N = 100) were in the third stage (bearing one cuticle) or moulting from the second stage to the third stage (bearing two cuticles). Euphausiids, particularly T. raschii, which represented 98% of the total euphausiids sampled, are important intermediate hosts of A. simplex in the St. Lawrence estuary. These data indicate the importance of the St. Lawrence estuary as an enzootic zone for A. simplex and thus a valuable area to study the biology and the transmission of this parasite.


1988 ◽  
Vol 66 (10) ◽  
pp. 2212-2222 ◽  
Author(s):  
Lena N. Measures

In Guelph Lake, a man-made reservoir in Ontario, Canada, prevalence of larval Eustrongylides tubifex in pumpkinseed (Lepomis gibbosus), rock bass (Ambloplites rupestris), and yellow perch (Perca flavescens) was 12.9% and mean intensity ranged from 1 to 1.8. Larvae were encapsulated on the mesentery of fish. Pumpkinseed and yellow perch were the important fish hosts in Guelph Lake as most larvae in these fish were alive. In contrast, 40% of larvae in rock bass were dead and calcified. Third- and fourth-stage larvae from naturally infected fish are described. Larvae in the three species of fish elicited a granulomatous inflammatory reaction. Attempts to transfer third-stage larvae from experimentally infected oligochaetes and third-stage larvae from naturally infected fish to laboratory-reared pumpkinseed were unsuccessful. Fourth-stage larvae from naturally infected fish were transferred successfully to pumpkinseed. Eutropic lakes such as Guelph Lake are particularly suitable enzootic areas because of the abundant populations of tubificid intermediate hosts and the presence of fish hosts such as pumpkinseed and perch. The advanced stage and development of larvae (to the fourth stage) in fish likely represents an adaptation for a parasite that occurs in a migratory host such as Common Mergansers (Mergus merganser), which frequent Guelph Lake for only about 1 month in spring and fall.


Author(s):  
Nydia Edith Reyes Rodríguez ◽  
Vicente Vega Sánchez ◽  
Fabián Ricardo Gómez de Anda ◽  
Patricia Beatriz García Reyna ◽  
Luis González de la Rosa ◽  
...  

Abstract Anisakisspp. nematodes are potentially zoonotic parasites; that infects a wide variety of aquatic species worldwide, with marine fish being the paratenic hosts. The aim of study was identify the presence of Anisakidae nematodes, and other parasites in Mugil curema . A total of 96 M . curema obtained from local markets in Tulancingo, Hidalgo, Mexico, were analyzed by necropsy. Only five M . curema present nematode collection in epaxial muscle. The tissues with the highest prevalence of parasites were identified, and samples of epaxial muscle with larval migration analyzed by histopathology. Visible parasites in necropsy tissues were classified according to their morphology. Nematode found in the liver were Contracaecum spp. (41.17%) and Pseudoterranova spp. third stage (7.36%); in the caudal part of the kidney were Anisakis spp. (13.23%), Pseudoterranova spp. third stage (11.77%) and Contracaecum spp. (5.88%); and in epaxial muscle were Anisakis spp. Larva I (5.88%) and Pseudoterranova spp (4.42%). In one fish, Clinostomum spp. was detected in epaxial caudal muscle. The present work reports for the first time the presence of nematodes of the family Anisakidae and Clinostonum spp. metacercariae, with zoonotic potential, in M . curema intended for human consumption in Tulancingo, Hidalgo, Mexico.


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