Effects Of Dietary Vitamin C And Interactions Of Vitamin E And Vitamin C On Reproductive Performance Of Turbot Broodstock

Feeding trials were conducted to investigate the effects of dietary vitamin C,interactions of vitamin E and vitamin C on reproductive performance of turbot(Scophthalmus maximus). The experiments were conducted in indoor floating waterculture pool. During the experimental periods, the dissolved`oxygen content wasgreater than6.0mg/L, the salinity ranged from30to32‰, the water temperatureranged from8to14℃. Results of these studies are presented as follows:1. An eight-month feeding experiment was conducted to determine the effects ofdietary vitamin C on reproductive performance of turbot Scophthalmus maximus.The basal diet was supplemented with0,800and4800mg/kg vitamin C toformulate three experimental diets. Results showed that the growth of turbotbroodstock was improved with the increasing dietary vitamin C. But no significantdifference was observed between control and vitamin C supplementation groups(P>0.05). The egg production of female broodstocks fed vitamin C supplementeddiets was significantly higher than that fed the control diet (P<0.05). No significantdifference of the egg production of turbot broodstocks was observed betweengroups800mg/kg and4800mg/kg (P>0.05), but the egg production of turbotbroodstocks fed4800mg/kg diet was higher than that in fish fed800mg/kg diet.The GSI, number of spawns, percentage of buoyant egg, fertilization rate andhatching rate of groups800mg/kg,4800mg/kg were significantly increased withthe improvement of vitamin C concentration in diets (P<0.05). Eggs and tissuesvitamin C concentrations significantly increased with the increasing dietary vitaminC (P<0.05). The egg diameter and oil globule diameter of turbot broodstocks was improved with the increasing dietary vitamin C, but no significant difference wasobserved between control and vitamin C supplementation groups. With theincreasing dietary vitamin C, the Superoxide ismutase (SOD) activities of in tissuessignificantly reduced (P<0.05), but Malonaldehyde (MDA) contents weresignificantly increased (P<0.05). So, it is concluded that vitamin C supplemented inthe diets of turbot broodstock can improve reproductive performance.2. An six-month feeding experiment was conducted to determine the effects ofvitamin C, vitamin E and the combination of vitamin C and E on growth andreproductive performance of turbot male broodstocks. The three isonitrogenous andisocaloric experimental diets were prepared with the supplementation of700mg/kgvitamin E (-C+E),800mg/kg vitamin C (+C-E) and the combination of700mg/kgvitamin E and800mg/kg vitamin C (+C+E) to the basal diet (-C-E). Resultsshowed the growth of turbot male broodstocks in the there groups of experiment-C+E,+C-E and+C+E were higher than that of experiment group-C-E, and nosignificant difference was observed among all experiment group (P>0.05). Spermvolume, TSI, sperm concentration, sperm motility and sperm morophology ofturbot male broodstocks in the there groups of experiment-C+E,+C-E and+C+Ewere significantly higher than that of experiment group-C-E (P<0.05). Especially,broodstocks fed+C+E diet showed highest these indicators in data among dietarytreatments. However, no significant difference was observed among all experimentgroups (P>0.05). Ascorbic acid and α-tocopherol concentrations in testicle andliver of turbot male broodstocks in the there groups of experiment-C+E,+C-E and+C+E were significantly higher than that of experiment group-C-E (P<0.05). Theascorbic acid concentrations of turbot male broodstocks in experiment group+C+Ewere the highest, then experiment group+C-E, but no significant difference wasobserved between two groups (P>0.05). However, the ascorbic acid concentrationsin testicle and liver of turbot male broodstocks in the two groups of experiment+C-E and+C+E were significantly higher than that of experiment group-C+E(P<0.05). The α-tocopherol concentrations of turbot male broodstocks inexperiment group+C+E were the highest, then experiment group-C+E, and no significant difference was observed between two groups (P>0.05). However,α-tocopherol concentrations in testicle and liver of turbot male broodstocks in thetwo groups of experiment-C+E and+C+E were significantly higher than that ofexperiment group+C-E (P<0.05). The ratio of PUFA/SFA in testicle of turbotmale broodstocks in the there groups of experiment-C+E,+C-E and+C+E werehigher than that of experiment group-C-E as well as the contents of n-3PUFA andn-6PUFA and these indicators of broodstocks of experiment group+C+E were thehighest among all dietary treatments. So, it is concluded that vitamin C and Esupplemented in the diets of turbot male broodstock can improve reproductiveperformance.