Effect Of Deb On Performance Of Cage-Rearing Ducks In Earlier Period Of Laying In Low Temperature

The experiment was conducted to study the requirements of DEB for cage-feeding Jin-ding ducks form 18-26 weeks. In the experiment, the 240 Jin-ding ducks of commercial strain (18 weeks of ages) were assigned to five groups randomly with eight replicates of six ducks per group. Each group was fed with DEB 150mmol/kg, 200mmol/kg, 250mmol/kg, 300mmol/kg, 350mmol/kg respectively, randomly arrangements. The experiment last eight weeks long, and the temperature was controlled at 4±2℃, and the humidity was 65%.The results of rearing experiment showed that in the stage from eighteen to twenty-six weeks, there was significant effect on the laying rate, ,the feed conversion rate and average diary gain (p<0.05), and there was no significant effect on the lng per day and average egg weight (p>0.05).The egg shell quality experiment showed that there was a significant effect on egg shell quality of cage-rearing laying ducks in the earlier period of laying under long time low temperature (p<0.05), but there was no significant effect on it during the last time (p>0.05).The egg shell intensity and shell thickness of the group receiving DEB value of 200mmol/kg²50mmol/kg was the highest.The results of incretion trail revealed that there was no significant effect on T₃, Cort and Ins (p>0.05), while there was significant difference on T₄ and T₄/T₃ (p<0.05).The results of antioxidant experiment revealed that DEB value has significant effect on T-AOC and MDA in serum under low temperature for a long time (p<0.05).The trial of serum biochemical indexes indicated that there was no significant difference on CO₂, TP, GLU, Na⁺, K⁺, Cl^-, Na⁺+K⁺-Cl^- and some enzyme, namely, LDH, CK, ALP and ALT, (p>0.05), and there was significant difference on Cr, BUN, OSM and AG (p<0.05).