Fish pain: Would it change current best practice in the real world?

Much of the “fish pain debate” relates to how high the bar for pain should be set. The close phylogenetic affinities of teleosts with cartilaginous fishes which appear to lack nociceptors suggests caution should be applied by those who seek to lower the bar, especially given the equivocal and conflicting nature of the experimental data currently available for teleosts. Nevertheless, even if we assume fish “feel pain,” it is difficult to see how current best practice in aquaculture would change. This is because of the need to avoid stress at all stages of the rearing process to optimize health, growth performance and post-slaughter product quality. For recreational angling, while the capture process may be stressful, there are data that suggest it is not painful, and the stress can be minimised using current best practice guidelines for recreational fisheries. In commercial fisheries, however, changes to current best practices may be required for some activities if fish pain were resolved in the affirmative

Reasons to Be Skeptical about Sentience and Pain in Fishes and Aquatic Invertebrates

The welfare of fishes and aquatic invertebrates is important, and several jurisdictions have included these taxa under welfare regulation in recent years. Regulation of welfare requires use of scientifically validated welfare criteria. This is why applying Mertonian skepticism toward claims for sentience and pain in fishes and aquatic invertebrates is scientifically sound and prudent, particularly when those claims are used to justify legislation regulating the welfare of these taxa. Enacting welfare legislation for these taxa without strong scientific evidence is a societal and political choice that risks creating scientific and interpretational problems as well as major policy challenges, including the potential to generate significant unintended consequences. In contrast, a more rigorous science-based approach to the welfare of aquatic organisms that is based on verified, validated and measurable endpoints is more likely to result in “win-win” scenarios that minimize the risk of unintended negative impacts for all stakeholders, including fish and aquatic invertebrates. The authors identify as supporters of animal welfare, and emphasize that this issue is not about choosing between welfare and no welfare for fish and aquatic invertebrates, but rather to ensure that important decisions about their welfare are based on scientifically robust evidence. These ten reasons are delivered in the spirit of organized skepticism to orient legislators, decision makers and the scientific community, and alert them to the need to maintain a high scientific evidential bar for any operational welfare indicators used for aquatic animals, particularly those mandated by legislation. Moving forward, maintaining the highest scientific standards is vitally important, in order to protect not only aquatic animal welfare, but also global food security and the welfare of humans

Transcriptome characterization of the South African abalone Haliotis midae using sequencing-by-synthesis

<p>Abstract</p> <p>Background</p> <p>Worldwide, the genus <it>Haliotis </it>is represented by 56 extant species and several of these are commercially cultured. Among the six abalone species found in South Africa, <it>Haliotis midae </it>is the only aquacultured species. Despite its economic importance, genomic sequence resources for <it>H. midae</it>, and for abalone in general, are still scarce. Next generation sequencing technologies provide a fast and efficient tool to generate large sequence collections that can be used to characterize the transcriptome and identify expressed genes associated with economically important traits like growth and disease resistance.</p> <p>Results</p> <p>More than 25 million short reads generated by the Illumina Genome Analyzer were <it>de novo </it>assembled in 22,761 contigs with an average size of 260 bp. With a stringent <it>E</it>-value threshold of 10^-10, 3,841 contigs (16.8%) had a BLAST homologous match against the Genbank non-redundant (NR) protein database. Most of these sequences were annotated using the gene ontology (GO) and eukaryotic orthologous groups of proteins (KOG) databases and assigned to various functional categories. According to annotation results, many gene families involved in immune response were identified. Thousands of simple sequence repeats (SSR) and single nucleotide polymorphisms (SNP) were detected. Setting stringent parameters to ensure a high probability of amplification, 420 primer pairs in 181 contigs containing SSR loci were designed.</p> <p>Conclusion</p> <p>This data represents the most comprehensive genomic resource for the South African abalone <it>H. midae </it>to date. The amount of assembled sequences demonstrated the utility of the Illumina sequencing technology in the transcriptome characterization of a non-model species. It allowed the development of several markers and the identification of promising candidate genes for future studies on population and functional genomics in <it>H. midae </it>and in other abalone species.</p

Hooking mortality of two species of shallow-water reef fish caught by recreational angling methods

The hooking mortality of two teleosts, the yellow stripey Lutjanus carponotatus (Lutjanidae), and the wire netting cod Epinephelus quoyanus (Serranidae), was examined for fish captured with lures and bait from shallow waters

Emergence of serranid pigment abnormality syndrome (SPAS) in wire netting cod (Epinephelus quoyanus) from Heron Island on the southern Great Barrier Reef

Coral reefs worldwide are under increasing stress from anthropogenic impacts, but there are relatively few reports of increased rates of disease in coral reef fish. Herein we report the emergence of abnormal skin lesions in wild-caught wire netting cod (Epinephelus quoyanus) near Heron Island in the southern Great Barrier Reef. The lesion involves conspicuous darkening and disorganisation of the brown ‘wire netting’ colouration pattern typical of this species, most commonly on the lower jaw, premaxilla and head, with occasional involvement of the flanks and dorsal fin in some fish. The lesion was not present during research conducted in the mid-1990s; however, since it was first recorded in 2012, the prevalence of grossly visible lesions has increased to 16.9% in 2017, with fish >340 mm long most affected (prevalence 64.7%). These data suggest emergence of the lesion is a recent phenomenon and that causative factors may be age related. Abnormal pigmentation lesions have only been observed to affect E. quoyanus and coral trout (Plectropomus leopardus; since 2010). Given the species affected and the currently unknown aetiology of these lesions, we name the condition serranid pigment abnormality syndrome (SPAS). Further research is required to determine its geographic distribution, establish causation and describe the course of disease in E. quoyanus

Investigation into white spots in the carapace of a moribund mud crab (Scylla serrata) from a white spot syndrome virus (WSSV) positive zone in Moreton Bay, Australia

Background A freshly deceased mud crab (Scylla serrata) exhibiting multiple white spots under the carapace was found in Pumicestone Passage, northern Moreton Bay in May 2018. This crab was taken from within a biosecurity zone established due to a recent incursion of White Spot Syndrome Virus (WSSV) into populations of wild penaeids (Penaeus spp., Metapenaeus spp.) and crabs (Thalamita crenata) in the area. Because grossly visible white spots have been previously observed under the carapace of moribund S. serrata with white spot disease (WSD) in India, an investigation into the cause of death was undertaken. Case report The affected S. serrata was negative for WSSV DNA when gill samples were tested by real-time PCR. Histopathology found no evidence of WSD lesions in the form of basophilic hypertrophied intranuclear inclusions in any tissues of ectodermal or mesodermal origin. Histopathology of the affected carapace showed that the white spots consisted of multiple lighter coloured foci in the exocuticle formed from concentric crystalline-like rings, which extended into the endocuticle. These were interpreted as evidence of mineral mobilisation within the carapace during the pre-moult (D1 or D2) stage of the moult cycle. The cause of death in this case therefore may have been due to moult-related complications. Conclusion These observations confirm that formation of grossly visible white spots under the carapace of S. serrata are not pathognomonic for infection with WSSV. Similar observations in previous studies where WSSV was detected by PCR in this same host may have been incidental findings