Effect of Nutritional Programming on Reproductive Performance and Quality of Progenies in Yellow Perch Perca flavescens

With the inclusion of larger percentages of soybean meal replacements in fish diets, the effect of nutrition on reproductive performance is questioned in respect to different protein quality.  This study examines both reproductive investment and progeny quality in Yellow Perch that have been nutritionally programmed on four different diets over the past two years.  Our goal was to determine if replacing fishmeal with wheat gluten or soybean meal protein would have an effect on fecundity, fertilization and larvae survival.  

Female Yellow Perch that had previously been nutritionally programmed with their first formulated feed on one of four different diets as juveniles were used.  The major protein sources that were altered within the diet were: fishmeal (Control), wheat gluten (WG), and two varieties of soybean meal (Soy A and Soy B).  In the spring of 2015, when females began ovulating, ribbons were stripped and fertilized with males that served as an outside control in order to eliminate variability in sperm quality. Survival counts were taken when the embryos were 2 cell to determine fertilization rate as well as at the 63 degree days (63°D), which was the start of the pigmented eyed stage.  Larvae were force hatched when ready and stocked in aquaria at a rate of 1,000-2,000/28L.  In order to determine differences between dietary treatments, the following parameters, were measured: weight of female after spawning, gonadal somatic index (GSI), egg size, fecundity, 2 cell fertilization rate and eyed stage survival (63°D).

Results showed that fishmeal protein replacement in diets, even up to 75%, did not have a significant effect on GSI, fertilization rate (%) at the two-cell stage, and eyed embryo stage survival (Figure 1).

Results of the transition of larvae to juveniles when transferred from live feed to dry diets will be presented.  Survival, daily growth rate, mean weight and food utilization of juveniles after 60 days on the "programming" diets (either fishmeal or soybean meal) will be presented.