The objective was to determine the effects of supplementing duck diets with Eucommia ulmoides oliv. leaf powder (EUL). Laying ducks (n = 480) were randomly allocated into 4 experimental treatments and fed diets containing 0, 1, 2, or 4% EUL. Dietary inclusion of EUL had no effect (p > 0.05) on laying performance or egg quality, but linearly increased (p < 0.05) total plasma protein, globulin, and HDL-C concentrations with concurrent reductions (p < 0.05) in plasma concentrations of cholesterol and LDL-C. Eggs laid by ducks receiving EUL had yolks with linearly higher phenolic concentrations (p < 0.05) but lower cholesterol concentrations (p < 0.05). EUL supplementation in duck diets significantly reduced n-6: n-3 PUFA ratio by enriching n-3 fatty acids in yolks (p < 0.05) with no changes in n-6 PUFA (p >0.05).

The aim was to investigate effects of various proportions (0 to 20%) of fermented rapeseed meal (FRSM) on performance, intestinal health, and antioxidant status in Sansui ducks (Sansui Sheldrake ducks). A total of 350 male ducklings, 15 d old, were allocated into five dietary treatments with seven replicate pens of 10 birds per pen. The starter diets had 0, 5, 10, 15, or 20% FRSM that contained 0, 1.08, 2.17, 3.25, or 4.34 µmol glucosinolates (GLS/g of complete feed, respectively, fed from d 15 to d 35. The average daily feed intake (ADFI) and feed conversion ratio (FCR) from d 15 to 35 increased linearly with the dietary FRSM inclusion, with the ducks fed 15 or 20% FRSM diets having higher (p < 0.05) ADFIs and FCRs than the ducks fed 0% FRSM. The dietary FRSM inclusion levels of up to 15% were accompanied by decreased catalase (CAT) and antioxidant capacity (AOC) activities in the livers and jejunum of the ducks at d 35. In addition, the 20% FRSM (4.34 µmol GLS/g diet) decreased the villus height, crypt depth, muscular thickness, and goblet cell counts in the jejunum and ileum. In conclusion, 15 or 20% dietary FRSM (3.25 or 4.34 µmol GLS/g diet) during the grower period in Sansui ducks decreased feed efficiency, disrupted hepatic antioxidant balance, and impaired intestinal morphology and structure. The FRSM inclusion of ≥15% (3.25 µmol glucosinolates/g) impaired feed efficiency and antioxidant activity, while the 20% FRSM (4.34 µmol glucosinolates/g) induced intestinal damage in the growing Sansui ducks.

This study evaluated the effects of dietary perilla seed meal (PSM) inclusion on growth performance, plasma biochemistry, and breast muscle fatty acid composition in Sansui ducks (Sansui Sheldrake ducks) from 4 to 8 wks of age. A total of 320 male ducks, 29 d old, were randomly assigned to 5 dietary treatments (0, 5%, 10%, 15%, or 20% PSM) with 8 replicates each group and 8 ducks per replicate. Results showed that PSM inclusion up to 20% did not significantly (p > 0.05) affect body weight, daily gain, feed intake, feed-to-gain ratio, or carcass traits. Plasma albumin, total cholesterol, and high-density lipoprotein cholesterol were elevated at 10% PSM inclusion (p < 0.05), while liver function markers remained unaffected (p > 0.05). As expected, dietary PSM supplementation dose-dependently enriched breast muscle n-3 polyunsaturated fatty acids, including α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (p < 0.05), and reduced the n-6/n-3 ratio (p < 0.05). These findings indicated that PSM could be incorporated into duck diets at levels up to 20% to enhance the nutritional value of duck meat without adverse effects on growth performance and health, supporting its use as a functional feed ingredient in sustainable duck production.