Trichinella papuae n.sp. (Nematoda), a new non-encapsulated species from domestic and sylvatic swine of Papua New Guinea

• Published in: International journal for parasitology Vol. 29; no. 11; pp. 1825 - 1839
• Main Authors: Pozio, E, Owen, I.L, La Rosa, G, Sacchi, L, Rossi, P, Corona, S
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-11-1999; Elsevier Science
• Subjects: Animals; Animals, Domestic; Animals, Wild; Base Sequence; Biological and medical sciences; DNA, Helminth - analysis; Female; Fundamental and applied biological sciences. Psychology; Invertebrates; Larva - ultrastructure; Male; Mice; Molecular Sequence Data; Molecular systematics; Morphology; Muscles - parasitology; Nemathelminthia. Plathelmintha; Nematode taxonomy; Non-encapsulated larvae; Papua New Guinea; Polymerase Chain Reaction; Ribosomal DNA; Sequence Analysis, DNA; Sus scrofa; Swine; Swine Diseases - parasitology; Systematics. Geographical distribution; Trichinella - classification; Trichinella - genetics; Trichinella - growth & development; Trichinella - isolation & purification; Trichinella papuae; Trichinellosis - parasitology; Trichinellosis - veterinary; Papua New Guinea; Melanesia; Oceania; Papua New Guinea; Non-encapsulated larvae; Morphology; Ribosomal DNA; Nematode taxonomy; Molecular systematics; Sus scrofa; Trichinella papuae; Encapsulation; Host parasite relation; Nurse cell; Taxonomy; Diagnosis (taxonomy); Wild animal; Cell transformation; Ultrastructure; Domestic animal; Nematoda; Ungulata; Parasite; Zoopathogen; Muscular fiber; Vertebrata; Mammalia; Transmission electron microscopy; Larva; Helmintha; Nemathelminthia; New species; Artiodactyla; Invertebrata
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/S0020-7519(99)00135-6

Encapsulated and non-encapsulated species of the genus
Trichinella are widespread in sylvatic animals in almost all zoogeographical regions. In sylvatic animals from Tasmania (Australian region), only the non-encapsulated species
Trichinella pseudospiralis has been reported. Between 1988 and 1998, non-encapsulated larvae of
Trichinella were detected in five domestic pigs and six wild boars from a remote area of Papua New Guinea. Morphological, biological, and molecular studies carried out on one strain isolated from a wild boar in 1997 suggest that these parasites belong to a new species, which has been named
Trichinella papuae n.sp. This species can be identified by the morphology of muscle larvae, which lack a nurse cell in host muscles, and whose total length is one-third greater than that of the other non-encapsulated species,
T. pseudospiralis. Adults of
T. papuae do not cross with adults of the other species and genotypes. Muscle larvae of
T. papuae are unable to infect birds, whereas those of
T. pseudospiralis do. The expansion segment V of the large subunit of the ribosomal DNA differs from that of the other species and genotypes. All of these features allow for the easy identification of
T. papuae, even in poorly equipped laboratories. The discovery and identification of a second non-encapsulated species in the Australian region strongly supports the existence of two evolutionary lines in the genus
Trichinella, which differ in terms of the capacity of larvae to induce a modification of the muscle cell into a nurse cell.