Histopathological investigation of four populations of abalone (Haliotis iris) exhibiting divergent growth performance.

The black-foot abalone (pāua), Haliotis iris, is a unique and valuable species to New Zealand with cultural importance for Māori. Abalone are marine gastropods that can display a high level of phenotypic variation, including slow-growing or 'stunted' variants. This investigation focused on identifying factors that are associated with growth performance, with particular interest in the slow-growing variants.

Histopathological changes in the greenshell mussel, Perna canaliculus, in response to chronic thermal stress.

Climate change associated temperature challenges pose a serious threat to the marine environment. Elevations in average sea surface temperatures are occurring and increasing frequency of marine heatwaves resulting in mortalities of organisms are being reported. In recent years, marine farmers have reported summer mass mortality events of the New Zealand Greenshell mussel, Perna canaliculus, during the summer months; however, the etiological agents have yet to be determined.

Bivalve digestive epithelial virosis (DEV): A cause of disease or a natural process?

Epithelial hyperplasia and sloughing of the digestive gland in bivalve mollusks are a global phenomenon and occur in species of commercial interest and cultural significance to indigenous peoples. Where hemocytosis, hyperplasia, and necrosis of digestive tubule cells have been observed associated with electron-dense uncoated virus-like particles (VLPs) 25-45 nm in diameter, the condition has been named digestive epithelial virosis (DEV). This condition has been associated with mortalities of some bivalve species in New Zealand.

New gregarine species (Apicomplexa) from tunicates show an evolutionary history of host switching and suggest a problem with the systematics of Lankesteria and Lecudina.

Apicomplexa (sensu stricto) are a diverse group of obligate parasites to a variety of animal species. Gregarines have been the subject of particular interest due to their diversity, phylogenetically basal position, and more recently, their symbiotic relationships with their hosts. In the present study, four new species of marine eugregarines infecting ascidian hosts (Lankesteria kaiteriteriensis sp.

Investigating the genetic structure of the parasites Anisakis pegreffii and A. berlandi (Nematoda: Anisakidae) in a sympatric area of the southern Pacific Ocean waters using a multilocus genotyping approach: first evidence of their interspecific hybridization.

The southern Pacific Ocean, off the New Zealand coast, has been reported as one sympatric area of the two parasite species Anisakis pegreffii and A. berlandi. Here, a multilocus genotyping approach, based on a panel of eleven DNA microsatellite (SSR) loci plus the sequences analysis of the nuclear nas10 nDNA and the mitochondrial mtDNA cox2 gene loci, was applied to a total of N = 344 adults and larvae of Anisakis spp.

A novel nuclear marker and development of an ARMS-PCR assay targeting the metallopeptidase 10 (nas 10) locus to identify the species of the Anisakis simplex (s. l.) complex (Nematoda, Anisakidae).

The genus Anisakis represents one of the most widespread groups of ascaridoid nematodes in the marine ecosystem. Three closely related taxa are recognized in the Anisakis simplex (s. l.

Cross-species utility of microsatellite loci for the genetic characterisation of Anisakis berlandi (Nematoda: Anisakidae).

Eight microsatellite loci, recently developed in the species Anisakis pegreffii, were successfully amplified in Anisakis berlandi, sibling species of the A. simplex (s. l.

Flow cytometric characterization of hemocytes of the flat oyster, Ostrea chilensis.

The flat oyster, Ostrea chilensis, native to New Zealand (NZ) and Chile is considered an important ecological, cultural and fisheries resource. Currently, commercial landings of this species in NZ are restricted due to low population numbers caused by ongoing mortalities resulting from the presence of the haplosporidian parasite, Bonamia exitiosa. More recently, the arrival of B.

Morphological and molecular diversity of rissoellids (Mollusca, Gastropoda, Heterobranchia) from the Northwest Pacific island of Hokkaido, Japan.

This study deals with four species of marine microgastropods of the family Rissoellidae. Rissoella elatior (Golikov, Gulbin Sirenko, 1987), R. golikovi (Gulbin, 1979), R.

PCR test to specifically detect the apicomplexan 'X' (APX) parasite found in flat oysters Ostrea chilensis in New Zealand.

Described here is a polymerase chain reaction (PCR) test to detect the apicomplexan-X (APX) parasite of a flat oyster species, Ostrea chilensis, endemic to New Zealand. The test primers target sequences in the in situ hybridisation probes identified to bind specifically to APX 18S rRNA and amplify a 723 bp DNA product. The test did not amplify 18S rRNA gene sequences of other apicomplexan species, including Toxoplasma gondii, Neospora caninum, Selenidium spp.

Distribution of Tetrodotoxin in the New Zealand Clam, , Established Using Immunohistochemistry and Liquid Chromatography-Tandem Quadrupole Mass Spectrometry.

Tetrodotoxin (TTX) is one of the most potent neurotoxins known. It was originally thought to only occur in puffer fish but has now been identified in twelve different classes of freshwater and marine organisms, including bivalves. Despite being one of the world’s most studied biotoxins, its origin remains uncertain.

Bonamia ostreae in the New Zealand oyster Ostrea chilensis: a new host and geographic record for this haplosporidian parasite.

Previous reports of the haplosporidian parasite Bonamia ostreae have been restricted to the Northern Hemisphere, including Europe, and both eastern and western North America. This species is reported for the first time in New Zealand infecting the flat oyster Ostrea chilensis. Histological examination of 149 adult oysters identified 119 (79.

Phylogenetics of Bonamia parasites based on small subunit and internal transcribed spacer region ribosomal DNA sequence data.

The genus Bonamia (Haplosporidia) includes economically significant oyster parasites. Described species were thought to have fairly circumscribed host and geographic ranges: B. ostreae infecting Ostrea edulis in Europe and North America, B.

Genetic and morphological approaches distinguish the three sibling species of the Anisakis simplex species complex, with a species designation as Anisakis berlandi n. sp. for A. simplex sp. C (Nematoda: Anisakidae).

Numerous specimens of the 3 sibling species of the Anisakis simplex species complex (A. pegreffii, A. simplex (senso stricto)), and A.

Anisakis nascettii n. sp. (Nematoda: Anisakidae) from beaked whales of the southern hemisphere: morphological description, genetic relationships between congeners and ecological data.

A new anisakid nematode, Anisakis nascettii n. sp., is described from beaked whales Mesoplodon spp.

Towards cryopreservation of Greenshell mussel (Perna canaliculus) oocytes.

Cryopreservation is a powerful tool for selective breeding in aquaculture as it enables genetic material from selected stock to be stored and crossed at will. The aim of this study was to develop a method for cryopreserving oocytes of the Greenshelltrade mark mussel (Perna canaliculus), New Zealand's main aquaculture species. The ability of oocytes to be fertilized post-thawing was used as the criterion for success in initial experiments and then subsequently, the ability of frozen oocytes to develop further to D-stage larvae was assessed.

Genetic relationships among Anisakis species (Nematoda: Anisakidae) inferred from mitochondrial cox2 sequences, and comparison with allozyme data.

The genetic relationships among 9 taxa of Anisakis Dujardin, 1845 (A. simplex (sensu stricto), A. pegreffii, A.

Evidence for a new species of Anisakis Dujardin, 1845: morphological description and genetic relationships between congeners (Nematoda: Anisakidae).

In the present study, a new biological species of Anisakis Dujardin, 1845, was detected in Kogia breviceps and K. sima from West Atlantic waters (coast of Florida) on the basis of 19 (nuclear) structural genes studied by multilocus allozyme electrophoresis. Fixed allele differences at 11 enzyme loci were found between specimens of both adults and larvae of the new species and the other Anisakis spp.