The occurrence of Pomphorhynchus laevis (Acanthocephala) in cage-reared rainbow trout (Oncorhynchus mykiss) from Işıklı Spring, Çivril, Turkey

Abstract

Occurrence of Pomphorhynchus laevis (Müller, 1776) in cage-reared rainbow trout Oncorhynchus mykiss (Walbaum, 1792) and the effects of parasitism on the fish condition were studied between July and November 2014 in Işıklı Spring. A total of 221 O. mykiss specimens were examined. In addition to P. laevis, three other parasite species; Trichodina sp., Ichthyophthirius multifiliis Fouquet, 1876 and Diplostomum sp. were also recorded. P. laevis was numerically the predominant species with the highest prevalence (77.8%), mean intensity (6.74), and mean abundance (5.24). In total 1160 P. laevis specimens were collected. The mean abundance of P. laevis increased over a period of months from 2.5 individual parasites per fish in July to 7.1 in November. The mean intensity of P. laevis increased with increasing fish host length from 1.5 in the 5.0-6.9 cm length class to 18.4 in the 25.0-26.9 cm length class. Although there was no statistically significant bias in the spatial distribution of P. laevis within the gut (p ˃ 0.05), the parasite tended to prefer the pyloric caeca (47.9%). The larval stage (cystacanth) of the acanthocephalan parasite were obtained from the haemocoel of Gammarus obnixus Karaman and Pinkster, 1977. The value of Fulton's condition factor (K) ranged from 0.84 to 1.66.

The genome, transcriptome, and proteome of the fish parasite Pomphorhynchus laevis (Acanthocephala)

“…It was also found together with anadromous and catadromous fish in the waters of the North Sea and the White Sea [77,79,[81][82][83][84][85][86][87], thus covering the entire range of aquatic habitats known for Acanthocephala as a whole. Not least, P. laevis belongs to the best-studied acanthocephalan species in terms of morphology, ecology, life history, and pathogenicity in aquaculture [8,[88][89][90].…”

Pathological Changes of Rainbow Trout (Oncorhynchus Mykiss Walbaum, 1792) Intestines Infected with Pomphorhynchus Laevis

“…Fish were anaesthetised using MS-222 and their spinal cords cut with dissecting scissors. Identification of acanthocephalan speciments was made according to Moravec ( 2004) and Cevrimel and Soylu (2017).…”

“…The pathology of P. laevis infection in the alimentary tract of the Antalya barb (Capoeta antalyensis), the chub (Leuciscus cephalus), the rainbow trout (Oncorhynchus mykiss) and the stone loach (Noemachileus barbatulus) was demonstrated in earlier studies (Aydogdu et al, 2011;Dezfuli, 1991;Wanstall et al, 1986;Wanstall et al, 2006). In Turkey, some authors have recorded P. laevis in freshwater fishes and also amphibian hosts (Yildiz et al, 2004;Cevrimel and Soylu, 2017…”

Morphological and molecular data show no evidence of the proposed replacement of endemic Pomphorhynchus tereticollis by invasive P. laevis in salmonids in southern Germany

“…Variation in mitochondrial COI and ribosomal ITS DNA further suggest that geographical populations of P. laevis diverged gradually since the late Miocene leading to genetically [16,28] and morphologically distinct lineages [16], whereas genetic variation in P. tereticollis is low, with populations starting to diverge from Middle Pleistocene [28]. The relation between the morphological and genetic classification of P. laevis and P. tereticollis has recently been questioned again, as molecular and morphological data seemingly pointed to a different species classification [29,30]. This has consequences for the interpretation of distribution patterns of the two species.…”