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The stable isotope values of nitrogen ([[delta].sup.15]N) and carbon ([[delta].sup.13]C) have been widely used in ecological studies to decipher the trophic relationships and interactions that occur between living organisms. The aim of this study was to determine the trophic relationship between a commercially important tropical Australian marine fish (Protonibea diacanthus (Lacepede, 1802)) (Sciaenidae) and its associated parasites, through stable isotope analysis of nitrogen and carbon ([[delta].sup.15]N and [[delta].sup.13]C). We examined the stable isotope ecology of four parasitic organisms: adult ectoparasitic copepods, and endoparasitic adult digeneans and nematodes and plerocercoids. Nitrogen in endoparasites was consistently depleted when compared with the host; however, digeneans expressed nitrogen signatures almost equivalent to those of the host. Ectoparasitic copepods were the only parasite that was substantially enriched in nitrogen compared with the host. All adult parasitic organisms were carbon depleted when compared with the host tissue associated with the site of infection; however, plerocercoids were enriched. Our findings emphasize the complexity of parasite-host interactions and the varying values of isotopic discrimination between parasite type, life-cycle stage, and location in host. Key words: helminth, copepod, Protonibea diacanthus, black-spotted croaker, marine fish, isotope, parasite ecology, Introduction Parasitism is a complex life history strategy that is ubiquitous across all ecosystems. Parasites are critical components of biodiversity, playing an integral role in ecosystem functioning and food web [...]

Research on parasites in Australian birds is limited. This study aimed to identify patterns of parasite burdens and their distribution across Australia in Anatidae species. Data were gathered from databases and the Australian Helminth Collection, then analysed using a Microsoft Excel spreadsheet. The findings reveal that platyhelminths were more frequently reported than nematodes, while acanthocephalans were the least abundant and least diverse parasites. At least 119 parasitic helminth taxa were recorded in Australian Anatidae (22 species from 16 genera), based on 271 records from 44 published articles and five museum/research institution collections. Specifically, 76 cases of nematode infection (33 taxa) were found among 20 Anatidae species, 102 cases of trematode infection (42 taxa) among 22 species, and 90 cases of cestode infection (40 taxa) among 16 species. The high prevalence of platyhelminths may be due to the host diet and the parasites' ability to multiply asexually in various larval stages among trematodes, increasing the likelihood of exposure and infection. The study also highlights the challenges in accurately identifying parasites due to many records being identified only at higher taxonomic levels. This issue is exacerbated by a scarcity of taxonomists and insufficient investment in capacity building in the country. Moreover, the available knowledge about the geographical distribution of Anatidae parasites in Australia is biased by the location of research institutions rather than the actual distribution of parasites. The introduction of non-native parasites through bird movement and introduced domestic waterfowls across borders poses a significant risk to native wildlife, potentially leading to new disease outbreaks or exacerbating existing health issues. [ABSTRACT FROM AUTHOR]

Linguatula serrata ("tongue worm") is a zoonotic intranasal parasite found globally in wild dogs, free‐ranging dogs, some domestic dogs, and vulpids. Since there are no sensitive tests currently available, infections are underdiagnosed. This is a pilot observational prospective study aimed at determining whether nasal linguatulosis can be diagnosed using CT. The secondary aims were to evaluate radiography, rhinoscopy, and nasal egg swabs as methods in the diagnosis of tongue worms. Fifty‐four wild canids and three vulpids euthanased by gunshot were sourced from pest‐control officers. Cadaver heads were subjected to helical CT examination, nasal‐swabbed for tongue worm eggs, and necropsied. Radiographs and rhinoscopy were performed on cadavers suspected to be infected based on preliminary CT examination. Tongue worms were retrieved at necropsy in 25 dogs and one fox. CT findings in animals with no nasal cavity ballistic damage were reviewed in six infected dogs and one infected fox. Adult female tongue worms were identified in 4 of 6 dogs and 1 of 1 fox as long, tubular, slightly heterogeneously attenuating structures in the mid to caudal nasal cavities. They were not clearly visible in CT scans when surrounded by nasal fluid, and small parasites (male and immature females) were not discernible. Radiographic findings were mild and nonspecific. One tongue worm was detected in 1 of 12 dogs examined rhinoscopically. Tongue worm eggs were found in swabs from 7 of 25 dogs. While small tongue worms could not be detected with CT, CT proved to be a useful diagnostic method for visualizing adult female tongue worms. [ABSTRACT FROM AUTHOR]