Eric Ignatz

• Doctor of Philosophy
• Postdoc at Dalhousie University

This study examined the effect of rearing temperature on growth performance and nutrient utilization of AquAdvantage Salmon (growth hormone transgenic female triploid Atlantic salmon) reared in a land-based freshwater recirculating aquaculture system (RAS) at three temperatures (10.5 °C, 13.5 °C, 16.5 °C) from first-feeding to 1500 g. All fish were...

This study describes the process of developing an enzymatic pretreatment to improve the nutritional value of feather meal (FeM). In a first experiment, a full factorial design was used to examine the effects of various incubation conditions on the solubilization of nitrogen in FeM. We incubated FeM for 3 h with various levels of a commercial alkali...

In recent lab‐based experiments, some post‐smolt Atlantic salmon (Salmo salar) held at 3°C for 5 weeks exhibited a range of clinical signs. They became lethargic and swam at the water's surface, developed ulcers to the head and jaw (clinical signs similar to tenacibaculosis in Norwegian salmon aquaculture) and had fin erosion, and this was associat...

In recent years there have been a number of instances where declines in water temperature are suspected to have contributed to winter mortalities at salmon cage-sites in Atlantic Canada. In addition, it is expected that temperature variability due to more intense and frequent winter storms will increase with climate change, and this may further thr...

Escape of genetically distinct farmed Atlantic salmon (Salmo salar) raises concerns about their potential interactions with wild populations and the disruption of local adaptation through genetic admixture. It is often unknown whether genetic origin or common domestication effects will have a greater influence on consequences posed by escaped farme...

Atlantic salmon (Salmo salar) are not only the world’s most economically important farmed fish in terms of total value, but also a salmonid, which means that they are invaluable for studies of the evolutionary fate of genes following multiple whole-genome duplication (WGD) events. In this study, four paralogues of the molecular chaperone serpinh1 w...

In this study, post-smolt male Atlantic salmon, previously identified as low (LR) or high responders (HR) based on post-stress cortisol levels, had their head kidney and liver sampled at 12 and 20°C prior to injection (time 0) and after (i.e., at 12 and 24 hpi, respectively) they were injected with either Forte Micro (a multi-valent vaccine contain...

Although it is known that the whitefish, an ancient salmonid, expresses three distinct gonadotropin-releasing hormone (GnRH) forms in the brain, it has been thought that the later-evolving salmonids (salmon and trout) had only two types of GnRH: GnRH2 and GnRH3. We now provide evidence for the expression of GnRH1 in the gonads of Atlantic salmon by...

Rising sea surface temperatures and heat waves are a challenge to salmon aquaculture, and the industry must endeavour to mitigate their impacts. To investigate genetic-based differences in upper thermal tolerance, 20 salmon families were exposed to an incremental temperature increase (+0.2 °C per day from 12 °C) to mimic the rise in temperatures ex...

Atlantic salmon (Salmo salar) is one of the most economically important aquaculture species globally. However, disease has become a prevalent threat to this industry. A thorough understanding of the genes and molecular pathways involved in the immune responses of Atlantic salmon is imperative for selective breeding of disease-resistant broodstock,...

The salmon aquaculture industry must be proactive at developing mitigation tools/strategies to offset the potential negative impacts of climate change. Therefore, this study examined if additional dietary cholesterol could enhance salmon production at elevated temperatures. We hypothesized that supplemental cholesterol could aid in maintaining cell...

This study examined the impact of rearing temperature (10.5, 13.5 or 16.5°C) on the hepatic transcriptome of AquAdvantage Salmon (growth hormone transgenic female triploid Atlantic salmon) at an average weight of 800 g. Six stranded PE libraries were Illumina-sequenced from each temperature group, resulting in an average of over 100 M raw reads per...

Fish can be identified as either low responders (LR) or high responders (HR) based on post-stress cortisol levels and whether they exhibit a proactive or reactive stress coping style, respectively. In this study, male Atlantic salmon (Salmo salar) from 17 families reared at 9°C were repeatedly exposed to an acute handling stress over a period of fo...

AquAdvantage Salmon (growth hormone transgenic female triploid Atlantic salmon) are a faster-growing alternative to conventional farmed diploid Atlantic salmon. To investigate optimal rearing conditions for their commercial production, a laboratory study was conducted in a freshwater recirculating aquaculture system (RAS) to examine the effect of r...