Project description:Chemical signals are produced by aquatic organisms following predatory attacks or perturbations such as parasitic infection. Ectoparasites feeding on host fish are likely to cause release of similar alarm cues into the environment due to the stress, wounding and immune response stimulated upon infection. Alarm cues are often released in the form of proteins and peptides and provide important insights into bodily function and infection status. Here we outline a non-invasive method to identify potential chemical cues associated with infection in fish by extracting, purifying and characterizing proteins from water samples from cultured fish. Gel free proteomic methods were deemed the most suitable for protein detection in saline water samples. It was confirmed that proteins could be characterized from teleost water samples and that variation in protein profiles could be detected between infected and uninfected individuals and fish and parasite only water samples. Our novel assay provides a non-invasive method for assessing the health condition of both wild and farmed aquatic organisms. Similar to environmental DNA monitoring methods, these proteomic techniques could provide an important tool in applied biology and aquaculture biology
Project description:Hypoxia is an important environmental stressor in aquatic ecosystems, with increasingly impacts on global biodiversity. Yellow catfish is an economically important farmed fish in China, which has increased dramatically. We investigated the response of hybrid yellow catfish to hypoxia under experimental conditions and focused on the analysis of the differential expression patterns of specific genes associated with hypoxia response by RNA-seq and qPCR analysis. A total of 1556 genes were captured significantly differentially expressed, and were categorized into immune response and energy metabolism. Functional enrichment analysis revealed the NLR signaling pathway play pivotal roles in hypoxia tolerance and resistance. Our study provides important insights into the physiological acclimation, immune response and defense activity of hybrid yellow catfish under hypoxia challenge.