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A G Chabaud

Publications and source records attributed to A G Chabaud.

At least 73 records · Page 4Linked to original sources
PubMed1981

[A new classification of Trichostrongyloidea nematodes (author's transl)].

The preliminary classification that we proposed in 1977 grouped provisionally in the family Amidostomatidae all the primitive Trichostrongyloidea (with the exception of the Strongylacanthidae). The study of several nematodes from reptiles and amphibians, and above all parasites of Australian monotremes and marsupials, lead us to split up this family. We believe that two families, Amidostomatidae and Strongylacanthidae evolved from ancestors close to the Ancylostomatoïdea. All the others, however, appear to have evolved from the Strongyloïdea. The morphological characters considered permit the elucidation of three principal evolutionary lines, recognized for the primitive forms by the anatomy of the caudal bursa and for specialized forms by the structure of the synlophe. The principal evolution of the group seems to have occurred during the Secondary Era in Gondwanaland. The families and sub-families remain very numerous in the Neotropical and Australian zones.

Amphibians↗
PubMed1981

[Molineinae parasites of mammals].

A revision of Molineinae parasitic in mammals is proposed with the following taxonomic changes: 1) Removal of the genera Ortleppstrongylus Durette-Desset, 1970, from a Bathyergidae of South Africa and Moguranema Yamaguti, 1941, from a Talpidae insectivore of Japan. Both genera are placed in Trichostrongylidae-Cooperiinae for the first, Trichostrongylidae-Haemonchinae for the second. 2) Division of the genus Molineus into two groups separated principally by the arrangement of the bursal rays. a) Molineus sensu stricto, parasitic in Carnivores throughout the world and in South american monkeys; with rays 2 and 3 grouped together and parallel, and with rays 4 equidistant between the 3 and 5. b) Brygoonema n. gen., Hugotnema, n. gen., Nochtia (Nochtia) Travassos and Vogelsang, 1929, and Nochtia (Tenrecola) n. sub. gen., parasitic in Tenrecoidea insectivores of Madagascar and Africa, and Erinacoidea insectivores and lemurs of Africa, with rays 2 and 3 diverging and the papilla of the ray 4 closer to the 3 than the 5. 3) Resurrection of the genus Shattuckius Sandground, 1938 parasitic in Solenodon of Hispaniola. 4) Synonymy of Hooperstrongylus Lie Kian Joe et Ow Yang, 1963 with Pithecostrongylus Lubimov, 1930. The species Molineus vogelianus De Muro, 1933 and M. teocchii Quentin, 1970, parasitic in lemurs are placed in Pithecostrongylus. Hypotheses on the evolution of the Molineinae of mammals are presented, based primarily on the evolution of the bursa. From the basic pattern observed in Molineinae of amphibians and reptiles (rays 2-3 grouped, ray 4 with common base with the 5-6, rays 5-6 grouped), evolution has followed two principal lines: 1) Displacement of the papilla of the ray 4 towards the anterior and disappearance of the common base with the 5-6. 2) Extremities of rays 2-3 and 5-6 converging forming two separate pincer-like formations. Following these and other secondary characters, an evolutionary hierarchy is proposed for the 13 genera. The parasites of Tenrecoidea of Madagascar are apparently of central importance in this evolution. A list of genera and species is given.

Animals↗
PubMed1980

[New data on the circadian cycle of Plasmodium. Preliminary note].

A frozen strain of Plasmodium yoelii nigeriensis is inoculated at 4 pm, midnight and 9 am onto inbred Mice. In all instances young gametocytes (type 0) appear in the blood only between 10 am and 6 pm. Although the erythrocytic schizogony occurs regularly during the whole circadian period, the latency increases progressively when the infective subinoculations are made at midnight, 4 pm and 9 am. Possibly, the infective merozoite can only enter the red blood cell around midnight.

Animals↗
PubMed1979

[New data on the biology of gametocytes of Plasmodium yoelii yoelli gathered from morphological characteristics indicating their age].

A morphological study has been made of the gametocytes of P. yoelii (a parasite of Rodents belonging to the "vivax" group). The authors distinguish 4 types chronologically ordered. Moreover, morphology enables one to predict their infectivity. The morphological analysis represents a tool leading to new data on the biology of gametocytes: loss of infectivity as soon as the parasitaemia becomes high; infectivity restricted to the young stages; concentration of young stages in the blood ingested by the Mosquitoes; short periodicity and short lived infectivity.

Animals↗
PubMed1975

[The mechanism controlling the crossing of the vector's stomach wall by microfilariae (Dipetalonema dessetae-Aedes aegypti)].

In some of the human filariasis, the number of microfiliariae which succeed in crossing the vector's stomach wall is smaller when the number of ingested microfilariae is larger (limitation). In the couple Dipetalonema dessetae-Aedes aegypti, this phenomenon appears to be due to a specific lysis of the stomach cells invaded by the microfilariae. This reaction is started when the microfilariae are very numberous. There is "information" transmitted to the whole of the vector's stomach.

Aedes↗
PubMedDate not supplied

[Trichostrongyloidea nematodes, parasites of Microchiroptera].

1. a) List of Nematodes collected by Professor Aellen in european Microchiroptera. Additionnal morphological data to the study of Molinostrongylus alatus, M. panousei, M. skrjabini. Description of M. aelleni n. sp. b) Description of M. richardae n. sp., M. benexae n. sp. et M. bauchoti n. sp., parasites of malagasian Molossidae. c) Description of M. colleyi n. sp. and M. owyangi n. sp., parasites of Malaysian Vespertilioninae, and of Allintoschius dunni n. sp., discovered in Myotis mystacinus from Malaysia and Pipistrellus nanus from Africa. 2. Taking into account the characteristics of the synlophe, the 17 species of the genus Molinostrongylus may be divided into five groups, each one being reasonably well characteristic of the genus of their Chiropteran host. 3. The composition of the Trichostrongyloidea fauna of Chiroptera and its relationship with Trichostrongyloidea from other Mammals (Tupaiidae, Pholidotes, Primates, Sciuridés) are analysed. Six groups are separated and divided into two well defined lines: 1) genus Strongylacantha, and 2) 12 genera stemming more or less directly from the Molineinae, 4. The three conical outgrowths at the tip of the female tail which differenciate presently the Anoplostrogylinae from the Molineinae appear to be an unreliable characteristic. The two subfamilies form a complex group which will be better understood if the evolution of the synlophe and that of the caudal bursa of the males are taken into account.

Animals↗
PubMedDate not supplied

Scanning electron microscopy of the cephalic structures of Pneumospiruridae. (Thelazioidea - Nematoda). Revision of the family.

In a study with the scanning electron microscope (SEM) five different types of cephalic structure were found in five species of Pneumospiruridae recorded in Israel. The description, in the literature, of a sixth type, based on a study with the light microscope, was also considered in evaluating the results. By comparing descriptions and drawings of the known Pneumospiruridae with the SEM micrographs the species in the family were grouped into two genera: 1. Vogeloides Dougherty, 1952 in which the form of the cephalic structures could be correlated with the structure of the oesophagus; 2. Metathelazia Skinker, 1931 in which the cephalic structures could not be correlated with any other morphological or anatomical character. The species included in the genus Metathelazia were therefore grouped on the basis of the form of cephalic structures in 5 types: booliati, multipapillata, acomysi, capsulata and rodentium. The genus Pneumospirura Wu and Hu, 1938 is considered a subjective synonym of Metathelazia.

Animals↗
PubMedDate not supplied

[Description of P. cyclopsi n. sp. a parasite of the microchiropteran bat Hipposideros cyclops in Gabon (author's transl)].

P. cyclopsi sp. nov. is characterized by the small size of the asexual stages and by gametocytes belonging to the type "malariae". It is related to P. anomaluri and the hosts of both species share the same habitat: hollow trees of the tropical forest. By the ancientness of its vertebrate host and its relationship with the "malariae" group of Haemosporidia P. cyclopsi is interpreted as a primitive species.

Animals↗