CSIR Junior Research Fellowship to Preeti

Arora is gratefully acknowledged. “
“Concerns about freshwater pollution from fish farming have led to the development of high-performance low-phosphorus (P) diets, resulting in a reduced nutrient output (Vandenberg and Koko, 2006). However, questions have been raised regarding the impact of insufficient P during rapid fish growth on the occurrence of vertebral deformities (Sugiura et al., 2004, Fjelldal et al., 2012a and Fjelldal find more et al., 2012b). In most cases, skeletal abnormalities in early stages are not visually detectable (Witten et al., 2005) and may be reversed to a certain degree, hence the importance of understanding initial underlying biological mechanisms. To date, transcriptomic data are still lacking regarding specific bone response to P deficiency. Here, we used RNA-sequencing technology, which appeared suitable to generate transcriptomic information on non-model species (McGettigan, 2013 and Fox et al., 2014). This study aims to provide a more comprehensive reference transcriptome for the bone tissue in trout as well as to annotate and highlight sequences that have biological functions involved in P regulation. It is intended as a first step permitting quantitative genomic studies on the skeletal SP600125 tissue in relation

to P requirements. All-female triploid rainbow trout (Oncorhynchus mykiss) were transferred (N = 1680, initial mass 60.8 ± 1.6 g; St-Alexis-des-Monts Inc., Canada) to the experimental facilities of the Laboratoire de recherche des sciences aquatiques (LARSA), Université Laval (Québec, Canada). Fish were initially acclimated for two weeks and fed a commercial

feed (Corey Optimum 3 mm) in accordance to the manufacturer’s tables. Thereafter, fish were fed with Rebamipide practical diets, either P-deficient (D, available P: 0.29%) or P-sufficient (S, available P: 0.45%), already tested in our laboratory ( Deschamps et al., 2014, Le Luyer et al., 2014 and Poirier Stewart et al., 2014). Animal rearing, P status and vertebrae monitoring were assessed according to the published methods (see for details Le Luyer et al., 2014 and Poirier Stewart et al., 2014). Experiments took place in compliance with the guidelines of the Canadian Council on Animal Care (2005) and supervised by the Animal Protection Committee of the Université Laval. Fish sampling was performed to maximize the representation of fish sizes, diets and vertebral phenotypes (Table 1). Initially (week 0) and for P-deficient and P-sufficient diets (week 4), fish were randomly sampled. Two individuals displaying the two most common types of P-related vertebral deformities at week 27 were also added (Poirier Stewart et al., 2014). Three caudal vertebrae (V35–36–37) with ligaments and intervertebral tissues were collected from each fish. Hemal and neural arches were removed and the remaining body and flesh removed by rinsing and brushing with PBS (1X).