The parasitic life-cycle of the swine kidney worm Stephanurus dentatus Diesing

1969 ◽  
Vol 17 (4) ◽  
pp. 607 ◽  
Author(s):  
AH Waddall

Third-stage larvae of S. dentatus exsheath in and invade the tissues of a variety of animals. After oral infection of guinea pigs and pigs, third-stage larvae migrate principally from the small and large intestine via the portal blood, mesenteric lymphatics, and, to a lesser degree, the peritoneal cavity. Large numbers of larvae invade the liver, and it was shown that some larvae can escape from the liver and lungs. After infection via the skin, third-stage larvae migrate mainly to the lungs. There was evidence that some larvae undertake a tracheal migration from the lungs and subsequently penetrate the digestive tract. The third moult occurs in a variety of tissues, and by using transplantation techniques, it was shown that fourth-stage larvae are capable of extensive migration. The liver is the most suitable organ for the development of fourth-stage larvae and immature adult worms. The migratory behaviour of mature adult worms was studied by transplanting adult worms into the peritoneal cavity. One patent infection was established using this technique, but it appeared that most worms migrated randomly throughout the carcass.

1968 ◽  
Vol 42 (3-4) ◽  
pp. 269-278 ◽  
Author(s):  
D. N. Dhar ◽  
Kunwar Suresh Singh

1. A precipitate was formed at the oral opening, excretory pore and anal opening of the fourth stage juveniles of O. columbianum in the presence of immune serum in vitro, causing their immobilisation and subsequent death in large numbers. The precipitates failed to appear on these juveniles in normal serum or in saline; nor did they appear on the third stage juveniles on incubation in immune sera. Apparently the excretory-secretory products of the fourth stage juveniles of O. columbianum serve as antigen and play an important role in the stimulation of antibodies in the host.2. Inactivation of the immune serum did not destroy the precipitin type of antibody, nor was it affected when the immune animals had been treated with cortisone.3. Immune serum from animals receiving multiple infections showed a higher antibody titre.4. The possible way in which the antibody acts on the fourth stage juveniles, causing their immobilisation and subsequent death, is discussed.


2000 ◽  
Vol 78 (2) ◽  
pp. 182-190 ◽  
Author(s):  
Marianne Køie

Mature specimens of Cucullanus cirratus O.F. Müller, 1777 (Cucullanidae) were obtained from the pyloric caeca and intestine of Atlantic cod, Gadus morhua L., from Danish waters. Eggs embryonate in seawater. Third-stage larvae about 400 µm long, with amphids and dereids, hatch from the egg. Experimental studies indicated that third-stage larvae were infective to calanoid and cyclopoid copepods and sand gobies, Pomatoschistus minutus (Pisces, Gobiidae). Larvae entered the haemocoel of copepods but did not grow. In gobies, the third-stage larvae entered the intestinal mucosa and grew to 800 µm in length within 6 months. They were not encapsulated. Experimental infections of cod (8-30 cm long) showed that free-living third-stage larvae are not infective, whereas >700 µm long third-stage larvae from gobies survived in the cod. Third-stage larvae 700-1200 µm long occur in the stomach mucosa, where they develop and moult to fourth-stage larvae. The fourth-stage larvae then migrate to the pyloric caeca and anterior part of the intestine, where they moult and develop to the mature adult stage. No developmental stage became encapsulated. Naturally infected cod (>20 cm total length) harboured moulting third-stage larvae and <2 mm long fourth-stage larvae 2 months post capture. Naturally infected 4- to 5-month-old codlings (8-10 cm total length) harboured 2-3 mm long fourth-stage larvae only, indicating that they acquired the third-stage larvae as planktivorous fry only a few centimetres long. Cucullanus cirratus may have a life-cycle that involves copepod transport hosts and fish (gobies or cod fry) intermediate hosts. Postcyclic development occurs in gadoids when an infected cod is consumed by another cod (cannibalism). Examinations of 350 (8-78 cm total length) naturally infected cod showed that group 1 and older cod are infected throughout the year, with maximum prevalence of third-stage larvae in spring and summer. The greatest prevalence of gravid worms was observed in autumn.


Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 184-209 ◽  
Author(s):  
J. F. A. Sprent

1. Evidence from previous literature shows that puppies are commonly infected with larvae ofToxocara canisat birth and that prenatal infection can be produced by feeding embryonated eggs to pregnant bitches.2. Observations on fifty-eight dogs in Brisbane showed that all of twenty-nine puppies 1–6 months old were infected, while only three out of twenty-nine dogs over 6 months old were infected.3. In naturally infected puppies, 1–3 weeks old, it was found that at birth third-stage larvae were present in the lungs. Third-stage larvae continued to appear in the lungs for the first week of life; their length was 0·6–1·3 mm.4. Third-stage larvae were found in the stomach on the day after birth; at 3 days after birth fourth-stage larvae were found in the intestine.5. It appeared likely that the second moult occurs in puppies before birth, and that the third moult takes place at a length of 1·0–1·3 mm. in the lungs and stomach within the first week of life.6. By the beginning of the second week, fourth-stage larvae were fully grown and had commenced the fourth moult at a length of 5–7 mm.7. Throughout the second and third weeks, adults grew rapidly, reaching a length of about 67 mm. by the end of the third week, but no eggs had appeared in the faeces at this time.8. Experimental infection of mice with eggs showed that the larvae were distributed to the somatic tissues, few reaching the alimentary tract. The larvae did not progress beyond the second stage in the tissues of mice.9. Experimental infection of dogs with eggs showed that in dogs over 5 weeks old the larvae were distributed to the somatic tissues and did not reach the alimentary tract. The larvae did not progress beyond the second stage, though some of them showed signs of commencing the second moult. In contrast, 1 to 3-week-old puppies infected in the same way were found to harbour larvae in the alimentary tract. Though some of these larvae were probably derived from a naturally acquired prenatal infection, it was evident from the progress of development that the experimental infection resulted in the presence of second-stage larvae in the liver and lungs and that these larvae underwent the second moult, commenced development as third-stage larvae in the lungs, migrated into the stomach and developed to the adult stage in the intestine.10. Experimental infection of dogs and foxes with mice harbouring second-stage larvae in the tissues showed that, in some instances, development of larvae proceeded in the alimentary tract. No evidence of somatic migration was found in dogs infected in this way, but in foxes second-stage larvae were found in the lungs.11. The structure and development of the second, third and fourth stage is described in detail and found to resemble closely the development ofT. catilarvae (Sprent, 1956). Second-stage larvae from dog tissues had a length of 0·34–0·44 mm. and the second moult occurred at a length of 0·37–0·44 mm. Third-stage larvae varied in length from 0·46 to 1·36 mm., and the third moult occurred at a length of 0·98–1·3 mm. Fourth-stage larvae measured 1·2–6·3 mm., though moulting fourth-stage larvae were observed up to a length of 7·4 mm. Sexual differentiation occurred during the fourth stage and was evident at a length of about 1·5 mm.12. The migratory behaviour of the larvae ofT. canisandT. catiis compared and discussed in relation to their wide range of hosts. It is concluded that differences in migratory behaviour are adaptations to prevailing modes of nutrition and it is suggested that the somatic migration occurring in dogs is an adaptation to the non-predatory habits of this particular host.


Horticulturae ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 131
Author(s):  
Matteo Zucchini ◽  
Arash Khosravi ◽  
Veronica Giorgi ◽  
Adriano Mancini ◽  
Davide Neri

The growth of cherry fruit is generally described using a double sigmoid model, divided into four growth stages. Abiotic factors are considered to be significant components in modifying fruit growth, and among these, the vapor pressure deficit (VPD) is deemed the most effective. In this study, we investigated sweet cherry fruit growth through the continuous, hourly monitoring of fruit transversal diameter over two consecutive years (2019 and 2020), from the beginning of the third stage to maturation (forth stage). Extensometers were used in the field and VPD was calculated from weather data. The fruit growth pattern up to the end of the third stage demonstrated three critical steps during non-rainy days: shrinkage, stabilization and expansion. In the third stage of fruit growth, a partial clockwise hysteresis curve of circadian growth, as a response to VPD, appeared on random days. The pattern of fruit growth during rainy days was not distinctive, but the amount and duration of rain caused a consequent decrease in the VPD and indirectly boosted fruit growth. At the beginning of the fourth stage, the circadian growth changed and the daily transversal diameter vs VPD formed fully clockwise hysteresis curves for most of this stage. Our findings indicate that hysteresis can be employed to evaluate the initial phenological phase of fruit maturation, as a fully clockwise hysteresis curve was observable only in the fourth stage of fruit growth. There are additional opportunities for its use in the management of fruit production, such as in precision fruit farming.


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.


PLoS ONE ◽  
2013 ◽  
Vol 8 (8) ◽  
pp. e72084 ◽  
Author(s):  
Rong-Jyh Lin ◽  
Jie-Wen He ◽  
Li-Yu Chung ◽  
June-Der Lee ◽  
Jiun-Jye Wang ◽  
...  

2021 ◽  
Vol 42 (1) ◽  
pp. 19-24
Author(s):  
J.H. Buduwara ◽  
T. Adiel ◽  
R. Sami ◽  
M.L. Tafem

The development of resistance by Culex mosquitoes to synthetic insecticides has necessitated the continued search for alternative ones from plants. This study screened the preliminary qualitative phytochemicals and assessed the larvicidal efficacy of extracts of J. gossypiifolia leaf against third and fourth stage Culex quinquefasciatus larvae. The J. gossypiifolia was screened for the presence of phytochemicals using standard methods. After twenty-four (24) hours post exposure of both third and fourth stage C. quinquefasciatus larvae against different concentrations, (2.0mg/ml, 4.0mg/ml, 6.0mg/ml, 8.0mg/ml and 10 mg/ml) of various extracts. It showed that larval mortality increases significantly (p<0.05) with increase in extracts concentration. Acetone leaf extract showed highest mortality at 10mg/ml with 85% third stage Culex larvae mortality, followed by ethanolic leaf extract. However, least mortality was observed in n-Hexane leaf extract with 15% larval mortality against fourth stage Culex larvae. Low LC and LC values (3.715mg/ml and 12.490mg/ml) were noticed in 50 90 acetone leaf extract of J. gossypiifolia. The study observed that the highest LC and LC values (9.104mg/ml and 50 90 22.877mg/ml) were noticed in hexane leaf extracts. Conclusively, acetone leaf extract of J. gossypiifolia can be harnessed to control Culex larvae. However, there is a need to ascertain the quantities of bioactive components of J. gossypiifolia and its toxicity to non-target organisms. Keywords: Jatropha gossypiifolia, Phytochemicals, Culex larvae


2020 ◽  
Vol 2 (3) ◽  
pp. 301-320
Author(s):  
Muhamad Sidik Triadi ◽  
Irfan Sanusi ◽  
Lida Imelda Cholidah

ABSTRAK Penulisan ini bertujuan untuk mengetahui manajemen humas radio Rama FM Bandung dalam meningkatkan pemasang iklan dari mulai tahapan perencanaan, pengorganisasian, pelaksanaan sampai dengan pengawasan, metode penelitian ini menggunakan metode kualitatif untuk mengetahui karakteristik  dengan cara berinteraksi secara langsung dan mendalam mengenai sebuah program dan ringkasan yang digambarkan pada konteks di atas mendasari untuk menggali dan mendeskripsikan kegiatan-kegiatan yang dijalankan oleh radio Rama FM Bandung dalam meningkatkan pemasang iklan. Analisis penelitian ini menggunakan deskriptif kualittaif. Hasil penelitian menunjukan bahwa kegiatan manajemen humas radio Rama FM Bandung dalam meningkatkan pemasang iklan dimulai pada tahapan pertama yaitu perencanaan pembuatan proposal, inovasi program, pengemasan iklan dan penyampaian iklan. Tahapan kedua yaitu pengorganisasian dengan komunikasi, membentuk team, pertimbangan tugas, dan persetujuan dari pimpinan. Tahapan ketiga yaitu pelaksanaan sesuai tugas, presentasi, pelaksanaan tugas sesuai susunan, pelaksanaan kegiatan. Tahap keempat yaitu pengawasan koordinasi, kinerja team yang bertugas, program yang berlangsung, dan pengawasan proses sebagai bahan evaluasi. Kata Kunci : Manajemen Humas; Meningkatkan; Pemasang Iklan. ABSTRACT This writing aims to determine radio public relations management Rama FM Bandung in increasing advertisers from the stages of planning, organizing, implementation to supervision, this research method uses a case study method to determine the characteristics by interacting directly and deeply about a case and summary illustrated in the above context underlying to explore and describe the activities carried out by radio Rama FM Bandung in improving advertisers. The analysis of this study uses descriptive qualitative. The results showed that the radio public relations management activities of Rama FM Bandung in increasing advertisers began in the first stage, namely the planning of making proposals, program innovation, packaging of advertisements and delivery of advertisements. The second stage is organizing with communication, forming teams, considering assignments, and approval from the leadership. The third stage is the implementation of tasks, presentations, implementation of tasks according to the arrangement, implementation of activities. The fourth stage is monitoring coordination, the performance of the team in charge, the ongoing program, and monitoring the process as an evaluation material. Keywords : Management Public Relations; Improve; Advertiser.


1950 ◽  
Vol 1 (3) ◽  
pp. 285 ◽  
Author(s):  
DF Stewart

All antigen was developed to detect circulating antibodies by means of the complement fixation test in sheep infested with Haemonchus contortus and Trichostrongylus spp. Extraction of worm material at 100°C. for 10 minutes was found to be the most satisfactory method for the preparation of antigens. Potent antigens were prepared from young adult H. contortus, from third-stage infective larvae, and from the eggs. Old mature adult H. contortus yielded antigens of low potency. No significant difference was found between the potency of antigens prepared from male and female adult H. contortus collected from the same sheep. Both adult Trichostrongylus spp. and third-stage infective larvae consistently yielded antigens of high potency. No significant difference was found in the results obtained with larval or adult H. contortus antigens, adjusted to the same potency and tested with natural H. contortus antisera. H. contortus and Trichostrongylus spp. absorbed the antiserum to each other. It was shown that a lipid was an essential constituent of the boiled antigen in the complement fixation reaction with natural antisera. Lipid-free antigens from H. contortus failed to react with natural antisera. The lipid was not antigenic when injected into rabbits. The carbohydrate fraction of H. contortus did not fix complement in the presence of natural antisera and was not antigenic when injected into rabbits. The lipid fraction of a variety of nematode parasites reacted with natural antisera to H. contortus infestation. Similar lipid fractions of two species of trematodes did not react with natural antisera to H. contortus infestation. Normal saline suspensions of the lipid-free material from a variety of helminths showed a greater degree of specificity when tested with artificially prepared antisera than did the lipid fractions.


2021 ◽  
Vol 64 (2) ◽  
pp. 309-320
Author(s):  
Mihajlo P. Fejsa

In this paper, the author compares chromatic terms in Ruthenian and Serbian. He focuses on the basic colour terms according to Berlin and Kay: white, black, red, green, yellow, blue, brown, purple, pink, orange, and grey. They have equivalents in both languages: Ruthenian bila – Serbian bela, čarna – crna, červena – crvena, željena – zelena, žovta / žolta – žuta, belava – plava, braon – braon, lilova – ljubičasta, celova – roze, pomarančecova /poma- randžecova – narandžasta, šiva – siva. The criterion of one-morpheme word is not appli- cable to the terms lilova, celova, and pomarančecova /pomarandžecova in Ruthenian, and ljubičasta and narandžasta in Serbian. It is applicable to the terms bila, čarna, červena, željena, žovta / žolta, belava, braon, and šiva. With the exception of braon, all these terms are derived from the Proto-Slavic language (*bеlъ, *čьrnъ, *čьrvenъ, *zelenъ, *žltъ, *polvь, and *sivъ). As far as the Berlin–Kay’s universal of seven phases of colour formation is con- cerned, our study of chromatic terminology confirms it. In accordance with the supposed first stage of development, the Ruthenian language has bila and čarna; according to the second stage, Ruthenian has červena; in accordance with the third stage, Ruthenian has že- ljena or žovta / žolta; according to the fourth stage, Ruthenian has žovta / žolta or željena; in accordance with the fifth stage, Ruthenian has belava; according to the sixth stage, it has braon; and in accordance with the seventh stage (even if we leave aside the multi-mor- pheme terms lilova, celova, and pomarančecova /pomarandžecova), it has šiva. Generally speaking, the usage of the terms is identical in both investigated languages but there are several differences (e.g. cibulja – beli luk, željena pasulja – boranija). The most frequent suffixes are -asta and -ista in Ruthenian, and -asta in Serbian.Most of the chromatic terms are of Slavic origin but there are several borrowings used for nuance purposes in recent decades, e.g. azurna, teget, akvamarin, tirkizna, and others. Some borrowings remain unchanged, e.g. in both languages blond, braon, drap, krem, bež, and oker, and only in Serbian lila and roze. Hungarian was the official language until the first decades of the 20th century (until the collapse of the Austro-Hungarian Monarchy in 1918), during which Ruthenian–Hungarian bilingualism reigned. That is the reason why several Hungarian colour names are found, e.g. in surnames (the Ruthenian surname Barna comes from Hungarian barna ‘brown’, Fekete/Feketa is from fekete ‘black’, and Vereš is from vörös ‘red’) and in the names of domestic animals (the Ruthenian horse name pejka [Serbian riđan] comes from Hungarian pej ‘brown’ and šarga [Serbian žutalj] is from sár- ga ‘yellow’). The general name for ‘colour’ comes from the German language (Ruthenian farba is from German Farbe).


Sign in / Sign up

Export Citation Format

Share Document