Programming of the hepatic lipid metabolism via a parental high carbohydrate low protein diet in rainbow trout

In rainbow trout (Oncorhynchus mykiss), the effect of a paternal and a maternal high carbohydrate-low protein diet was assessed on progeny at long term. To this purpose, two-year old male and female rainbow trout were fed either a control diet or a high carbohydrate/low protein diet for an entire reproductive cycle for females and for 5 months for males. Crossed-fertilizations were carried out in order to obtain 4 groups of offspring. Offspring were fed with a commercial diet until they reached a market size and were then challenged with a complete plant-based diet for 3 months. After the challenge, hepatic transcriptomes were analysed to detect any effect of the parental diet on offspring metabolism. Two-year old male and female rainbow trout were fed either a control diet (NC, 63.89% protein and 0% carbohydrates) or a high carbohydrate/low protein diet (HC/LP, 42.96% protein and 35.30% carbohydrates) for an entire reproductive cycle for females and for 5 months for males. During the spawning period, spawns from NC and HC/LP females were cross-fertilized with milts from males from each experimental condition. Thus, offspring from 4 different conditions were obtained: NN (offspring from both males and females fed the control NC diet); HN (offspring from only females fed the HC/LP diet and males fed the control NC diet); NH (offspring from only males fed the HC/LP diet and females fed the NC diet); and HH (offspring from both parents fed the HC/LP diet). Offspring were reared into 9 tanks (n=3/condition) in a flow-though rearing system supplied with natural spring water at 17°C. Since their first feeding, fish were fed ad libitum with a commercial diet (T3-P Omega, Skretting, France). After 6 months, juveniles were fed during a 3-month trial a complete plant-based diet. At the end of the challenge, liver were sampled in offspring (n=6 per confition).