TY - JOUR
T1 - Microhabitat preference of Anisakis simplex in three salmonid species
T2 - immunological implications
AU - Bahlool, Qusay Zuhair Mohammad
AU - Skovgaard, Alf
AU - Kania, Per Walter
AU - Haarder, Simon
AU - Buchmann, Kurt
PY - 2012/12/21
Y1 - 2012/12/21
N2 - Three salmonid fish species, Oncorhynchus mykiss, Salmo salar and Salmo trutta, were infected experimentally with the parasitic nematode Anisakis simplex (A. simplex) and the difference between in vivo behaviour of the nematode in the three fish species was investigated. Infection success rate differed between species. S. salar (Baltic salmon) showed the highest number of successfully established nematodes, whereas S. trutta (brown trout) and O. mykiss (rainbow trout) had a higher natural resistance. Microhabitat selection of nematodes differed according to fish species. In brown trout, A. simplex larvae were attached to the digestive tract (stomach, pyloric caeca, intestine), while the majority of larvae found in rainbow trout were located between the pyloric caeca. In Baltic salmon, nematodes were dispersed in and on spleen, head kidney, liver, swim bladder and musculature. Encapsulation and inflammatory cellular reactions differed accordingly. Histopathological and immunohistochemical studies using monoclonal antibodies raised against salmonid IgM, CD8 and MHCII were performed to detect the presence of immune cells around the infecting nematodes. None of the three fish species showed positive reactions for IgM-bearing cells in the inflammatory tissue connected with nematodes. CD8+ cells were detected in all three species and MHCII-bearing cells were found associated with encapsulated A. simplex in rainbow trout and brown trout, but not in Baltic salmon. Physiological, immunological and pathological implications of microhabitat differences are discussed.
AB - Three salmonid fish species, Oncorhynchus mykiss, Salmo salar and Salmo trutta, were infected experimentally with the parasitic nematode Anisakis simplex (A. simplex) and the difference between in vivo behaviour of the nematode in the three fish species was investigated. Infection success rate differed between species. S. salar (Baltic salmon) showed the highest number of successfully established nematodes, whereas S. trutta (brown trout) and O. mykiss (rainbow trout) had a higher natural resistance. Microhabitat selection of nematodes differed according to fish species. In brown trout, A. simplex larvae were attached to the digestive tract (stomach, pyloric caeca, intestine), while the majority of larvae found in rainbow trout were located between the pyloric caeca. In Baltic salmon, nematodes were dispersed in and on spleen, head kidney, liver, swim bladder and musculature. Encapsulation and inflammatory cellular reactions differed accordingly. Histopathological and immunohistochemical studies using monoclonal antibodies raised against salmonid IgM, CD8 and MHCII were performed to detect the presence of immune cells around the infecting nematodes. None of the three fish species showed positive reactions for IgM-bearing cells in the inflammatory tissue connected with nematodes. CD8+ cells were detected in all three species and MHCII-bearing cells were found associated with encapsulated A. simplex in rainbow trout and brown trout, but not in Baltic salmon. Physiological, immunological and pathological implications of microhabitat differences are discussed.
KW - Natural medicine
KW - Anisakis simplex
KW - Fish immunology
KW - Immunohistochemistry
KW - Anisakis simplex
KW - Fish immunology
KW - Immunohistochemistry
U2 - 10.1016/j.vetpar.2012.07.009
DO - 10.1016/j.vetpar.2012.07.009
M3 - Journal article
C2 - 22858638
SN - 0304-4017
VL - 190
SP - 489
EP - 495
JO - Veterinary Parasitology
JF - Veterinary Parasitology
IS - 3-4
ER -