Checklist of Fish Hosts of Species of Contracaecum Railliet & Henry, 1912 (Nematoda: Ascaridida: Anisakidae) in Iraq

Surveying literature concerning the occurrence of the nematode larval forms of the genus Contracaecum in fishes of Iraq, showed the infection of 44 freshwater and marine fish species in Iraq with such larvae. The infection included larvae of unidentified Contracaecum species, Contracaecum rudolphii type-B and Contracaecum septentrionale Kreis, 1955. The infections were distributed in Tigris, Euphrates and Shatt Al-Arab rivers as well as some of their tributaries, lakes, marshes, drainage networks in addition to many fish ponds and floating cages in different parts of Iraq. This checklist also provided references on some histopathological and biochemical changes, some ecological aspects of the infection, life cycle and scanning electron microscopy. In addition, this checklist includes literature on six species of adult Contracaecum species as well some unidentified species of this genus from 17 bird species from different parts of Iraq, of which both Eurasian bittern Botaurus stellaris and pygmy cormorant Microcarbo pygmaeus were infected with a maximum number of three Contracaecum species as well as unidentified species of this genus.

Morphology and Molecular Studies of Contracaecum Larvae (Nematoda: Anisakidae) in Some Fish species from Sulaimani Province, Kurdistan Region, Iraq

Contracaecum is a genus of nematodes belonging to the family Anisakidae, that parasitise many fishes which act as an intermediate or paratenic hosts, while the piscivorous birds and mammals are definitive hosts. A total of 44 third larval stage of Contracaecum were collected from 13 infected freshwater fishes belonging to five different species in different water bodies in Sulaimani Province, Kurdistan Region, Iraq from January to the end of December 2018. In this investigation, 966 fishes were collected including six species of Nemacheilidae, five species of Cyprinidae, three species of Leuciscidae, two species of Xenocyprididae, one species of each of Bagridae, Heteropneustidae, Mastacembelidae, Mugilidae, Siluridae and Sisoridae. This study revealed that five fish species (Cyprinus carpio, Luciobarbus barbulus, L. esocinus, L. xanthopterus and Mastacembelus mastacembelus) were infected with Contracaecum larvae with the prevalence of 2.05%, 0.92%, 1.92%, 19.35% and 1.06%, respectively. The Contracaecum larvae were morphologically studied by compound light microscope and the molecular analyses was done by amplification, sequencing and comparing different gene loci (ITS1, ITS2 and COX2) of isolated third larval stage of Contracaecum. The ITS1, ITS2 and COX2 were amplified by polymerase chain reaction (PCR) and sequenced. The sequences of ITS1, ITS2 and COX2 reveal that all Contracaecum larvae from all infected fishes represented exactly one species (Contracaecum rudolphii B) based on compering and identity percentage in Gene Bank database. Phylogenetic analysis of the genotype (for ITS1) was described. The genetic characterization of the Contracaecum larvae in the present study is available in the GenBank database and they were deposited in GenBank and their accession numbers were demonstrated.

Ultramorphology and molecular studies of Contracaecum larvae (Nematoda: Anisakidae) collected in five Cyprinid fish species from Sulaimani Province, Kurdistan Region-Iraq

Summary A total of 1134 freshwater fishes belonging to Cyprinidae (Acanthobrama marmid (n=20), Alburnus caeruleus (n=7), Alburnus mossulensis (n=62), Arabibarbus grypus (n=123), Barbus lacerta (n=7), Capoeta trutta (n=222), C. umbla (n=161), Carasobarbus kosswigi (n=5), C. luteus (n=89), Carassius auratus (n=54), Chondrostoma regium (n=52), Cyprinion kais (n=10) and C. macrostomum (n=322)) were collected in different water bodies in Sulaimani Province, Kurdistan Region-Iraq for the presence of larval nematode of the genus Conteacaecum. This investigation revealed that 17 fishes belonged to five species (A. marmid, A. grypus, C. trutta, C. luteus and C. regium) were infected with Contracaecum larvae with prevalence of 35 %, 0.81 %, 0.90 %, 4.49 % and 5.76 %, respectively. The third- larval stage was morphologically studied by optical microscopy, and the ultrastructure was investigated using scanning electron microscopy (SEM). In addition, molecular analysis was carried out by amplifying, sequencing and comparing different gene loci, including internal transcribed spacers (ITS-1 and ITS-2) and cytochrome oxidase c subunit-II (COX-2), of the different isolated Contracaecum larvae. These sequences were also compared with closely related nematode sequences from the GenBank. Fifteen sequences were obtained for this study from the collected Contracaecum larvae. ITS-1, ITS-2 and COX-2 were amplified by polymerase chain reaction (PCR) and sequenced. The sequences of ITS-1, ITS-2 and COX-2 revealed that the collected Contracaecum larval specimens from all infected fish species represented one species (Contracaecum rudolphii B) based on the identity percentage in the GenBank database. The genetic characterisation of the parasite in the present study is available in the GenBank database, and the obtained ITS-1, ITS-2 and COX-2 sequences were deposited in GenBank. The present study provides information on the accurate identification and molecular analysis of Contracaecum larvae in the infected fish species in Sulaimani Province, Kurdistan Region-Iraq.

Helminth parasites of shags (Phalacrocoracidae) from the Otago region of southern New Zealand

A total of 61 specimens representing five species of shag – Auckland Island shag Leucocarbo colensoi, little pied shag Microcarbo melanoleucos brevirostris, black shag Phalacrocorax carbo novaehollandiae, Otago shag Leucocarbo chalconotus and spotted shag Phalacrocorax punctatus – from the coast around Otago, South Island, New Zealand, were examined for helminths. A total of 18 helminth species was found: six nematodes (Anisakis pegreffi, Contracaecum rudolphii E, Baruscapillaria sp., Cosmocephalus jaenschi, Ingliseria cirrohamata, Desmidocercella australis), four trematodes (Apatemon sp. ‘jamiesoni’, Cardiocephaloides ovicorpus, Apophallus sp., Microphallidae gen. sp.), four cestodes (Microsomacanthus cormoranti, Microsomacanthus sp., Paradilepis urceina, Tetrabothrius sp.) and four acanthocephalans (Andracantha leucocarboi, A. sigma, Corynosoma hannae, Profilicollis novaezelandensis). Descriptions are provided for females of C. jaenschi and D. australis, which were previously undescribed. The data include 20 new host records and seven new locality records. New 18S ribosomal DNA and internal transcribed spacer (ITS1 and ITS2) DNA sequences have been provided where specimen conditions permitted. These data add considerably to our sparse knowledge of helminths in New Zealand shags, and provide a baseline for observations of change in the future.

MOLECULAR CHARACTERIZATION OF CONTRACAECUM RUDOLPHII HARTWICH, 1964 (NEMATODA: ANISAKIDAE) FROM THE CORMORANT PHALACROCORAX CARBO IN IRAQ

Contracaecum rudolphii Hartwich, 1964 is a nematode which causes major concerns to human and wildlife animal’s health. However, the population genetics of C. rudolphii has been poorly studied in Iraq. In order to gain a deeper understanding in the outline of the genetic diversity of the nematode C. rudolphii that were isolated from its host cormorant Phalacrocorax carbo (Linnaeus, 1758), in the middle areas of Iraq, twenty specimens of C. rudolphii adults were isolated from nine individuals of P. carbo. The first (ITS-1) internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of C. rudolphii were amplified using conventional polymerase chain reaction (PCR); then, the amplicons were subjected to sequencing. Concatenation of ITS-1 (rDNA) sequences resulted in four unique genotypes that have not been previously recorded in Iraq. The present study showed that the most common genotype occurred in 85% of C. rudolphii, and in 88.9% of cormorants. Furthermore, the infrapopulation difference in the genotypes was fairly high, with an average of 1.3 ± 0.48 genotypes per host of those with ≥two nematodes. All the sequences of the current study were distributed into two different populations. The sequences of ITS-1 for the first population had the highest similarity to ITS-1 sequence of C. rudolphii B, while the sequences of ITS-1 for the second population had the highest similarity to ITS-1 sequence of C. rudolphii A. This study provides an insight about the genetic divergence of C. rudolphii among P. carbo in Iraq. As well, the results likely support the hypothesis that C. rudolphii represents a complex of at least two sibling species.

New insights into the coexistence of Contracaecum rudolphii A and Contracaecum rudolphii B (Nematoda: Anisakidae) in Phalacrocorax carbo sinensis from Sardinia: genetic variability and phylogenetic analysis

Contracaecum sp. nematodes are important parasites of fish eating birds that can cause animal health problems. In the present study, specimens of Contracaecum rudolphii sensu lato, from the great cormorant Phalacrocorax carbo sinensis from Sardinia, were characterized based on morphological and molecular data. The morphological analysis allowed to identify all the fourth stage larvae (n = 1918) as Contracaecum sp., and adults, male (n = 5845) and female (n = 8312), as C. rudolphii sensu lato. Population genetics and phylogenetic relationships were inferred based on mitochondrial and nuclear markers. Multiple sequence alignment of the ribosomal internal transcribed spacer showed the coexistence of C. rudolphii A (n = 157), C. rudolphii B (n = 22) and a rare heterozygote of these species. Moreover, mitochondrial markers, namely NADH dehydrogenase subunits I (nad1), cytochrome c oxidase subunit (cox1 and cox2) and small subunit of rRNA (rrnS), showed that the studied C. rudolphii A populations had undergone bottleneck, or founder effect event, subsequent to a rapid population growth and expansion. The observed heterozygote is with a mitochondrial pattern of C. rudolphii B. Although, both Contracaecum species showed high genetic diversity, no genetic structure between localities was detected. Phylogenetic reconstructions supported the paraphyly of the avian Contracaecum species including C. ogmorhini (parasite of otariids).

Parasites of the Neotropic cormorant Nannopterum (Phalacrocorax) brasilianus (Aves, Phalacrocoracidae) in Chile

The Neotropic cormorant Nannopterum (Phalacrocorax) brasilianus (Suliformes: Phalacrocoracidae) is widely distributed in Central and South America. In Chile, information about parasites for this species is limited to helminths and nematodes, and little is known about other parasite groups. This study documents the parasitic fauna present in 80 Neotropic cormorants’ carcasses collected from 2001 to 2008 in Antofagasta, Biobío, and Ñuble regions. Birds were externally inspected for ectoparasites and necropsies were performed to examine digestive and respiratory organs in search of endoparasites. Ectoparasites collected were cleared and mounted for identification under a microscope. Fecal samples were also evaluated to determine the presence of protozoan parasites employing a flotation technique. A total of 44 (42.5%) of birds were infested with at least one ectoparasite species, while 77 (96.25%) were carrying endoparasites. No protozoan forms were found after examination. Most prevalent endoparasite species found were Contracaecum rudolphii s. l. (72/80, 90%), followed by Pectinopygus gyroceras (33/80, 41.25%), and Profilicollis altmani (26/80, 32.5%). This is the first report of P. altmani, Baruscapillaria carbonis, Avioserpens sp., Cyathostoma (Cyathostoma) phenisci, and Eidmaniella pelucida in the Neotropic cormorant. These findings also expand the distributional range of Andracantha phalacrocoracis, Paradilepis caballeroi, Hysteromorpha triloba, and P. gyroceras to Chile.