Effects of Cordyceps Feed Additive on Production Performance and Egg Quality in Laying Ducks

[ Objective ] To investigate effects of Cordyceps feed additive on growth performance, laying rate and egg quality in laying ducks. [ Method] A total of 270 healthy laying ducks were randomly divided into throe groups, 90 ducks in each group. The ducks in the control group, group I and group II were fed common basal diet, basal diet containing 10 g/kg Cordyceps feed additive and basal diet containing 40 g/kg Cordyceps feed additive, respectively. The trial lasted for 28 d. During the whole trial, the ducks were weighed and their growth was observed at an interval of 7 d. The exterior quality and the nutritive indexes of duck eggs were determined. [ Result] After experiments, the body weights of ducks in the group I and group II were increased and higher than that of the control group. In the group I and group II, the laying rate was increased by 1.07% and 2.15%, respectively; the egg weight was increased by 3.95% and 4.16%, respectively; and the feed to egg ratio was decreased by 2.54% and 4.23%, respectively. The egg shape and eggshell thickness were consistent between the control group and experimental groups. In the group I and group II, the protein content of the duck eggs was increased by 5.55% and 17.15%, respectively; the cholesterol content was decreased by 11.79% and 42.14%, respectively; the IgY level was increased by 13.20% and 27.97%, respectively; and the lecithin content was increased by 5.13% and 11.69%, respectively. [Condusion] The Cordyceps feed additive can increase the body weight and laying rate of laying ducks and improve the quality of duck eggs.

Desalted duck egg white nanogels as Pickering stabilizers for food-grade oil-in-water emulsion

Achieving the reuse of traditional egg by-products,salted duck egg whites(SEW),is an urgent problem to be solved.In this current work,we constructed a heat-induced gel-assisted desalination method for SEW.Subsequently,a top-down way was utilized to prepare desalted duck egg protein nanogels(DEPN)with uniformly distributed diameters and their application in the oil/water(O/W)interface system was explored.The results revealed that the increase of DEPN concentration could lower the droplet size,however,the size was negatively correlated with the oil phase fraction.Moreover,the effect of pH,ionic strength,and temperature on the emulsion stability demonstrated that the DEPN-stabilized emulsion displayed superior physical stability under different conditions.The addition of NaCl resulted in the significant decrease in droplet size of the emulsion,while further increasing the NaCl concentration,the droplet size did not decrease accordingly.Besides,heat-treatment and cold-treatment had little negative effect on the stability of the emulsion.Even if the droplet size of the emulsion increased at 80℃for 3 h,the morphology of the emulsion remained unchanged.Our study demonstrated DEPN had great potential as a stabilizer for food-grade Pickering emulsions.