THE LIFE HISTORY OF THE NEMATODE METABRONEMA SALVELINI (FUJITA, 1920) PARASITIC IN THE SPECKLED TROUT, SALVELINUS FONTINALIS (MITCHILL), IN QUEBEC

1955 ◽  
Vol 33 (1) ◽  
pp. 1-4 ◽  
Author(s):  
L. P. E. Choquette

In Quebec, the first larval stages of the spirurid, Metabronema salvelini (Fujita, 1920), parasitic in the speckled trout, Salvelinus fonlinalis (Mitchill), are to be found in nymphs of the mayfly, Hexagenia recurvata, and in those of a species of the genus Polymitarcys. The fourth larval stage develops in the fish host. The third and fourth larval stages are described. The feeding of larvae-harboring nymphs of Hexagenia recurvata to trout resulted in the establishment of infection and development of adult worms in from 60 to 70 days.

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.


Author(s):  
Marie V. Lebour

The present paper is a continuation of last year's work on the Euphausiidæ in the neighbourhood of Plymouth (Lebour, 1924), in which the early larval stages were described of Nyctiphanes Couchii, Meganyctiphanes norvegica and, less fully, those of Thysanoessa inermis and T. neglecta. These two last-named forms are reserved for a detailed description in another paper, only Nyctiphanes and Meganyctiphanes being dealt with here. The first paper described these as far as the last Calyptopis stages, and it was shown that they were much alike although perfectly distinct, especially as regards colour. The nauplii and metanauplii were easily distinguishable. The whole of the remaining life-history of Nyctiphanes Couchii has now been elucidated and also that of Meganyctiphanes norvegica, with the exception of a few late larval stages. The absence of these, however, does not materially affect our knowledge of its life-history.


2014 ◽  
Vol 11 (2) ◽  
pp. 943-951
Author(s):  
Baghdad Science Journal

The following dilution 5×10-1, 10-1, 10?2 , 10-3 gm/L for the indigenous isolate of Bacillus thuringiensis bacteria and the commercially isalate were used for experiments against the different stages of fig moth of E.cautella which exposed by filter paper method. The results showed that mortality of larval stages was increased with the increasing concentration of the biocide, in addition to increase in the mortality of the larval stages reached to the highest percentage in the third days of treatment of the larval stage in comparison with the first and second days of exposure. The results also showed that the sensitivity of larval stages was increased in first and second instars while reduced in the last instars .The high percentage of first instar mortality for the indigenous isolate in the concentration of 5×10-1 was 72.8% , while the low percentage of mortality showed in the concentration of 5×10-1 for the fifth instar larvae which was 13.3% in third days of treatment while a high percentage of mortality was showed for the first instar larvae for the commercially isulate in the concentration of 5×10-1 was 59.4% Furthermore, low percentage of mortality was shown in the concentration of 5×10-1 in fifth instar larval which was 8.3% in the third days of treatment. The results also showed that the indigenous isolated was more effective than the commercially produced bacteria for killing larval instars of fig moth E.cautella .The total percentage of larval instar mortality reached to 44.5 % after the third days of treatment in concentration 5×10-1 in the indigenous isolate , and it was 33.8 % in the commercially produced bacteria .


Author(s):  
J. E. Morton

The Plymouth Fauna List contains records of two genera of pteropods, Limacina and Clione. Of the first, Limacina retroversa (Flem.) is by far the better-known species, apparently occurring regularly at Plymouth in large numbers in townettings from outside, and sometimes inside, the Sound. It breeds at Plymouth from June to August, and Lebour (1932) has given a detailed account of its breeding and larval stages and has discussed its role in the plankton. The second species of Limacina at Plymouth is lesueuri (d'Orbigny), which has been observed from time to time since 1906, when it was very common. The last record in the Fauna is off the Breakwater in 1920. Of the gymnosomatous pteropods, Clione limacina Phipps is the only species regularly occurring. Lebour (1931) has described the life history of this form, and mentions February to August as its months of greatest abundance. Its breeding season is June to August. Another gymnosome, tentatively referred to as Clionina longicauda, is reported by Russell (1936), and from the specimen department at Plymouth Laboratory the writer obtained some preserved specimens, not easily identifiable, of a Pneumodermopsis taken locally; its species is perhaps ciliata, recorded by Massy (1917) from the Irish Coast.


1967 ◽  
Vol 15 (4) ◽  
pp. 739 ◽  
Author(s):  
RK Keith

Observations are reported on the morphology of the egg and infective larva, and on the development in calves of the parasitic stages of Cooperia pectinata Ransom. The third and fourth moults occurred 2 and 8 days, respectively, after infection. The pre-patent period was 13-14 days.


1987 ◽  
Vol 22 (3) ◽  
pp. 237-244 ◽  
Author(s):  
W. Davis Martin ◽  
G. A. Herzog

The life history of the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) (= Epitrix parvula Fab.) was studied under the controlled conditions of 27 ± 2.8°C, 80 ± 6% and a 14L:10D photophase. Eggs matured in ca. 4 days, the larval stage, including 3 instars, developed in 13 days, prepupal development took 3 days and the pupal stage lasted approximately 5 days. There was a 24 day interval between oviposition and adult emergence. Females laid 3.1 eggs/day with a 13 day period between adult emergence and first oviposition. The mean number of total eggs/female was 138.6 ± 14.7. Female oviposition continued until a few days before death and adult longevity was approximately 70 days. A visual means of distinguishing between male and female beetles was also developed.


1891 ◽  
Vol 23 (5) ◽  
pp. 106-108
Author(s):  
Harrison. G. Dyar

The preparatory stages of this species do not seem to have been described. Mr. Hy. Edwards in his catalogue gives eleven references, but in none is the egg mentioned, or any but a single larval stage, and in only one the pupa. It will, therefore, not be amiss to briefly describe the several stages here. I would like first to call attention to the remarkable fertility of the insect in question, at least in Southern Florida where I met with it.


Parasitology ◽  
1947 ◽  
Vol 38 (1-2) ◽  
pp. 10-16 ◽  
Author(s):  
H. A. Baylis

In a former paper (Baylis, 1944) an account was given of some observations on the life-history of Mermis nigrescens, and of its occurrence, naturally and experimentally, in earwigs (Forficula auricularia). As stated in that paper, the material then available did not seem to warrant an attempt to describe the larval development. Further material has now been obtained and studied, and it seems desirable to place on record some of the observations made, although many points still remain obscure.


1976 ◽  
Vol 108 (9) ◽  
pp. 931-934 ◽  
Author(s):  
P. Martel ◽  
H. J. Svec ◽  
C. R. Harris

AbstractLaboratory studies on the biology of the carrot weevil, Listronotus oregonensis (LeConte), were performed at 21° and 27 °C. At 21 °C females laid eggs for 88 days on carrot slices and 94 days on foliage. Egg production per female averaged 156 and 175 on slices and leaves respectively. Eggs hatched after 8.3 days incubation and the larval stage comprising four instars was completed in 19.1 days. The prepupal and pupal stages lasted 3.7 and 9.4 days respectively. The complete life cycle including an average preoviposition period of 17 days was 57.6 days. Development was more rapid at 27 °C, with the complete life cycle taking only 37 days.


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