Prabhugouda Siriyappagouder

Multidisciplinary approaches, including, but not limited to, pathology, epidemiology, marine and environmental sciences, and molecular biology. Early diagnostic tools play a key role in identifying pathogens and diseases, while prophylactic strategies such as vaccination, biosecurity measures, and good husbandry practices are vital for effectively controlling disease outbreaks. Our research collection Aquatic Animal Health and Epidemiology: Disease Surveillance, Prevention, and Control includes 10 research and review articles that have advanced our understanding of host-pathogen interactions, pathology, pathogen diversity, and their molecular characterization, as well as diagnostics and predictive surveillance modeling of disease dynamics within aquatic environments.Environmental stressors are increasingly affecting aquatic animal health, especially in open-sea cages, as climate change alters environmental conditions. A major challenge is maintaining optimal dissolved oxygen levels in cages. Cerqueira et al. ( 2024) developed a predictive model to estimate oxygen concentrations in cages. Factors such as rising water temperatures, algal blooms, eutrophication, and high stocking density reduce oxygen levels, leading to hypoxic conditions. Early detection of these conditions is crucial to reducing fish stress and improving their welfare. To address this, a machine learning method was used to predict hypoxia events in salmon farms.The emergence of new diseases remains a serious concern due to constantly shifting environmental conditions, interactions, and pathogen exchange between wild and farmed fish populations. Efforts continue to reduce the risk of pathogen transmission between wild and farmed populations, as well as from farms to the environment. conditions. The vaccine offered long-lasting immunity and protected against the challenge but 69 did not provide cross-protection against other strains of V. anguillarum. It provided a level of 70 protection similar to that of a commercial vaccine under field conditions for lumpfish in sea 71Vaccines, functional feeds, and biosecurity measures are essential to maintaining fish health, 73 boosting productivity, and promoting sustainability. Maintaining optimal water quality 74 parameters is also essential. Poor water quality can induce stress and suppress the fish's immune 75 system, leading to disease outbreaks. Using inorganic and organic materials to regulate primary 76 production and water quality parameters may have adverse effects on fish health due to residual 77 effects. Ciani et al. (2024) show that using calcium oxide (CaO) particles to treat fish farm 78 water can help reduce populations of sea lice, plankton, and echinoderms. The proper dose and 79 frequency of use effectively reduce unwanted biological entities, but CaO exposure did not 80 induce fish mortality or histopathological damage in the skin, eyes, or intestines. This highlights the health and welfare of fish. 83Genetics is also very important factor; it has become a key criterion in modern fish health management, enabling the development of disease-resistant strains. breeding 85 the production of inherited offspring that are more resistant to pathogens diseases 86 and that grow faster. Subsequently, dependence on vaccines, functional feeds, and disease-87 control agents can be reduced, thereby improving both profitability and sustainability of 88 Aquaculture is key to meeting global food needs, but infectious diseases pose a major concern 108 for these efforts. Improvements in disease detection, prevention, and monitoring help achieve 109 sustainable aquaculture production. This research topic presents a collection of articles offering 110 insights and recommendations for future research in aquatic animal health and epidemiology.

Oceans and coastal waters, vital for human survival and climate regulation, are increasingly threatened by heavy metal pollution due to human activities including industrialization and urbanization. Heavy metals including tin, zinc, mercury, copper, nickel, cadmium, cobalt, vanadium, strontium, titanium, arsenic, lead, molybdenum, and chromium are persistent pollutants that can accumulate in marine organisms, posing significant risks to ecosystems and human health. While some heavy metals are essential in trace amounts, they can exert undesirable biological effects at higher concentrations and even become toxic. In response to such toxic exposure, terrestrial and aquatic plants and animals are known to have evolved inherent mechanisms to subdue heavy metal toxicity. These responses often involve the activation of various stress-related proteins, including heat shock proteins, antioxidant enzymes, and metal-binding molecules that work collectively to restore cellular homeostasis. One of the mechanisms to mitigate metal toxicity is through the activity of metallothionein proteins. Metallothioneins, low molecular weight, cysteine-rich proteins, play a crucial role in mitigating the toxic effects of heavy metals. These proteins bind heavy metals, aiding in detoxification, protecting the cells from their undesirable effects, and maintaining metal homeostasis. Thus, metallothionein expression and activity also serve as valuable biomarkers for assessing heavy metal pollution, providing insights into the biological impact of these contaminants. The present review explores the role of bacterial metallothioneins in detoxification and their potential in environmental risk assessment, focusing on their importance in marine species exposed to heavy metal pollution. We explore the studies that report heavy metal contamination in the coastal waters, followed by elucidating the effects of heavy metal exposure on metallothionein activity and expression in marine fish, crustaceans and mollusks. Finally, we provide possible future perspectives of how bacterial metallothioneins can be employed for mitigating ecological damage caused by heavy metals. By understanding the interactions between heavy metals and metallothioneins, we can develop more effective strategies for monitoring and mitigating the effects of heavy metal contamination in marine environments.

Nile tilapia (Oreochromis niloticus) is the most widely farmed tilapia species globally, making it one of the most important aquaculture species. To meet increasing demand, hatcheries occasionally use artificial breeding techniques such as hormonal induction to synchronize breeding. Despite the common use of human chorionic gonadotropin (hCG) in fish breeding, no detailed protocol has been established specifically for Nile tilapia. The objective of this study is to establish an effective hCG-induced artificial breeding protocol for gene editing and aquaculture production, optimizing fertilization, hatching, and survival rates. We employed a single intramuscular injection of 2 IU/g hCG to induce ovulation. The protocol achieved an average fertilization rate of 88.3% and a larval survival rate of 90.5%, demonstrating its potential for obtaining high-quality embryos for functional studies and enhancing reproductive performance on a commercial scale.

Background Circular RNAs (circRNAs) are covalently closed-loop RNAs with critical regulatory roles in cells. The tenth of thousands of circRNAs have been unveiled due to the recent advances in high throughput RNA sequencing technologies and bioinformatic tools development. At the same time, polymerase chain reaction (PCR) cross-validation for circRNAs predicted by bioinformatic tools remains an essential part of any circRNA study before publication. Results Here, we present the CircPrime web-based platform, providing a user-friendly solution for DNA primer design and thermocycling conditions for circRNA identification with routine PCR methods. Conclusions User-friendly CircPrime web platform (http://circprime.elgene.net/) works with outputs of the most popular bioinformatic predictors of circRNAs to design specific circular RNA primers. CircPrime works with circRNA coordinates and any reference genome from the National Center for Biotechnology Information database (NCBI).

Consumption of lipid-rich foods can increase the blood cholesterol content. β-glucans have hypocholesterolemic effect. However, subtle changes in their molecular branching can influence bioactivity. Therefore, a comparative investigation of the cholesterol-lowering potential of two β-glucans with different branching patterns and a cholesterol-lowering drug, namely simvastatin was undertaken employing the zebrafish (Danio rerio) model of diet-induced hypercholesterolemia. Fish were allocated to 5 dietary treatments; a control group, a high cholesterol group, two β-glucan groups, and a simvastatin group. We investigated plasma total cholesterol, LDL and HDL cholesterol levels, histological changes in the tissues, and explored intestinal transcriptomic changes induced by the experimental diets. Dietary cholesterol likely caused the suppression of endogenous cholesterol biosynthesis, induced dysfunction of endoplasmic reticulum and mitochondria, and altered the histomorphology of the intestine. The two β-glucans and simvastatin significantly abated the rise in plasma cholesterol levels and restored the expression of specific genes to alleviate the endoplasmic reticulum-related effects induced by the dietary cholesterol. Furthermore, the distinct patterns of transcriptomic changes in the intestine elicited by the oat and microalga β-glucans impacted processes such as fatty acid metabolism, protein catabolic processes, and nuclear division. Oat and microalgal β-glucans also altered the pattern of lipid deposition in the liver. Our study provides insights into the effectiveness of different β-glucans to alleviate dysfunctions in lipid metabolism caused by dietary cholesterol.

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are proteins that contain highly conserved functional domains and sequence motifs that are correlated with their unique biophysical activities, to regulate cardiac pacemaker activity and synaptic transmission. These pacemaker proteins have been studied in mammalian species, but little is known now about their heart distribution in lower vertebrates and c-AMP modulation. Here, we characterized the pacemaker system in the heart of the wild Atlantic cod (Gadus morhua), with respect to primary pacemaker molecular markers. Special focus is given to the structural, ultrastructural and molecular characterization of the pacemaker domain, through the expression of HCN channel genes and the immunohistochemistry of HCN isoforms, including the location of intracardiac neurons that are adjacent to the sinoatrial region of the heart. Similarly to zebrafish and mammals, these neurons are immunoreactive to ChAT, VAChT and nNOS. It has been shown that cardiac pacemaking can be modulated by sympathetic and parasympathetic pathways, and the existence of intracardiac neurons projecting back to the central nervous system provide a plausible link between them.

Anti‐nutritional factors in dietary components can have a negative impact on the intestinal barrier. Here, we present soya bean‐induced changes in the intestine of juvenile zebrafish and the effect of yeast β‐glucan through a transcriptomic approach. The inclusion of soya bean meal affected the expression of several intestinal barrier function‐related genes like arl4ca, rab25b, rhoub, muc5ac, muc5d, clcn2c and cltb in zebrafish. Several metabolic genes like cyp2x10.2, cyp2aa2, aldh3a2b, crata, elovl4, elovl6, slc51a, gpat2 and ATP‐dependent peptidase activity (lonrf, clpxb) were altered in the intestinal tissue. The expression of immune‐related genes like nlrc3, nlrp12, gimap8, prdm1 and tph1a, and genes related to cell cycle, DNA damage and DNA repair (e.g. spo11, rad21l1, nabp1b, spata22, tdrd9) were also affected in the soya bean fed group. Furthermore, our study suggests the plausible effect of yeast β‐glucan through the modulation of several genes that regulate immune responses and barrier integrity. Our findings indicate a subdued inflammation in juvenile zebrafish fed soya bean meal and the efficacy of β‐glucan to counter these subtle inflammatory responses.