Fine structure of Longicollum pagrosomi (Acanthocephala: Pomphorhynchidae) and intestinal histopathology of the red sea bream, Pagrus major, infected with acanthocephalans.
The results described the structure of Longicollum pagrosomi and histopathological characters of the intestine of the red sea bream, Pagrus major, infected with acanthocephalans, using the light and electron microscopes. Among the six samples of P. major, L. pagrosomi was identified in the posterior intestine of five fish samples. Adult L. pagrosomi (total length, 8-27 mm) is divided into the presoma (proboscis, anterior neck, and posterior neck) and metasoma (trunk). The proboscis had vertically arranged hooks (40 μm in length), with ten hooks per row, and the septum was observed between the posterior neck and trunk. The tegument thickness of the proboscis was approximately 15 μm, and it was composed of thin, circular muscle fibers. The outer fibrous membrane was approximately 1 μm, and the connective tissue layer was approximately 35 μm in thickness in the anterior neck. The tegument of the posterior neck enclosed the cephalic ganglion and had longitudinal and vertical muscle fibers, and the tegument thickness was approximately 45 μm. The tegument of the body, which was approximately 1 mm in thickness, was composed primarily of muscle and collagen fibers, and the structure of the tegument was different, depending on the body region. The acanthocephalans had ovaries and oval-shaped eggs with an eggshell (77.5 × 17.1 μm), floating within the body cavity of the trunk. In the infected posterior intestine of P. major, the presoma and the anterior part of the metasoma of L. pagrosomi passed through the intestinal wall and infected the intestinal tissue, perforating the loose connective tissue. In the inflammatory connective tissue, collagen and muscle fibers were fragmented and revealed partial necrosis. Lipid drops and eosinophilic granular cells aggregated in the connective tissue of the tissue capsule. In the vicinity of the acanthocephalan, the mucosal epithelia contained hypertrophied nuclei, and the epithelial layer was collapsed. In an extreme case, the mucosal fold was degenerated because of pressure from the acanthocephalan.
Pathology Division, National Fisheries Research and Development Institute, Busan 619-902, South Korea.
Seok-Ryel
SR
Kim
Jung Sick
JS
Lee
Jeong-Ho
JH
Kim
Myung-Joo
MJ
Oh
Choon-Sub
CS
Kim
Myoung Ae
MA
Park
Jung Jun
JJ
Park
D000049:Acanthocephala / Q000302:isolation & purification / Q000648:ultrastructure*; D000818:Animals; D005393:Fish Diseases / Q000469:parasitology / Q000473:pathology*; D041981:Gastrointestinal Tract / Q000469:parasitology / Q000473:pathology*; D006374:Helminthiasis, Animal / Q000469:parasitology / Q000473:pathology*; D006651:Histocytochemistry; D007411:Intestinal Diseases, Parasitic / Q000469:parasitology / Q000473:pathology / Q000662:veterinary*; D008853:Microscopy; D021541:Sea Bream / Q000469:parasitology*
Bull Environ Contam Toxicol. 2010 Jan;84(1):125-31
19946663
J Vet Sci. 2006 Dec;7(4):339-42
17106224
Syst Parasitol. 2002 Jun;52(2):145-52
12075132
Int J Parasitol. 1993 May;23(3):391-7
8359988
J Parasitol. 1981 Jun;67(3):403-9
7264831
Syst Parasitol. 2004 Jun;58(2):149-58
15449830
Wien Klin Wochenschr. 2004;116 Suppl 4:19-23
15683038
Microsc Res Tech. 2008 Mar;71(3):230-5
17992690
Syst Parasitol. 2003 Mar;54(3):229-35
12652074
Parasite. 2001 Sep;8(3):231-6
11584753
Z Parasitenkd. 1986;72(1):105-14
3962428
Parasitology. 2003;126 Suppl:S53-60
14667172
J Helminthol. 2006 Jun;80(2):151-7
16768858