Department of Animal Science, University of Minnesota, St. Paul, MN.
West Central Research and Outreach Center, University of Minnesota, Morris, MN.
J Anim Sci. 2020 Apr 1;98(4). doi: 10.1093/jas/skaa079.
We hypothesized that the digestibility of a zinc polysaccharide complex is greater than zinc sulfate when sows consume high fiber diets containing corn dried distillers grains with solubles (DDGS). Gilts and sows (n = 32) were blocked according to parity and assigned randomly to one of four dietary treatments (n = 8 sows per treatments). Dietary treatments consisted of: 1) Control (ConZnSO4)-corn-soybean meal-based diet + 100 ppm supplemental Zn from ZnSO4; 2) Control PSZn (ConPSZn)-corn-soybean meal-based diet + 100 ppm supplemental Zn from Zn polysaccharide complex; 3) DDGS/ZnSO4-corn-soybean meal-40% DDGS gestation diet and a 30% DDGS lactation diet, with each containing 100 ppm supplemental Zn from ZnSO4; 4) DDGS/PSZn-corn-soybean meal-40% DDGS gestation diet and a 30% DDGS lactation diet, with each containing 100 ppm supplemental Zn from Zn polysaccharide complex. A fifth dietary treatment was imposed using a subset of sows (n = 20) to determine basal Zn losses in gestating and lactating sows fed corn-soybean meal-based diets containing no supplemental Zn. Nutrient balance experiments were conducted in both gestation and lactation to evaluate the digestibility of Zn sources of the four dietary treatments and to determine basal Zn losses when no supplemental Zn was provided. The statistical model included fixed effects of diet, Zn source, and their interaction, and random effects of parity. Estimated endogenous losses of Zn were used to adjust apparent total tract digestibility (ATTD) to true total tract digestibility (TTTD) of Zn in the four dietary treatment balance periods. There were no differences in Zn concentrations of urine, plasma, colostrum, or milk samples among treatments at any time of the experiment (P > 0.05). Gestating sows fed DDGS/PSZn had improved (P < 0.05) ATTD, TTTD, and overall retention of Zn compared with both Control treatments, with the DDGS/ZnSO4 treatment responses being intermediate. Lactating sows consuming diets without DDGS and supplemented with Zn polysaccharide complex had the greatest (P < 0.05) ATTD, TTTD, and retention of Zn, which were opposite to responses observed in gestation. Furthermore, ATTD, TTTD, and Zn retention for lactating sows consuming DDGS/PSZn were less (P < 0.05) than all other treatments. Overall, zinc digestibility of ZnSO4 and PSZn appears to be differentially influenced by the stage of the reproductive cycle and presence of dietary fiber from DDGS.
我们假设，当母猪食用含有玉米干酒糟及其可溶物（DDGS）的高纤维日粮时，锌多糖复合物的消化率高于硫酸锌。根据胎次将后备母猪和母猪（n = 32）分为若干组，并随机分配到四种日粮处理组（n = 8 头母猪/处理组）之一。日粮处理组包括：1）对照（ConZnSO4）-玉米-豆粕基础日粮+100 ppm 硫酸锌补充锌；2）对照 PSZn（ConPSZn）-玉米-豆粕基础日粮+100 ppm 锌多糖复合物补充锌；3）DDGS/ZnSO4-玉米-豆粕-40% DDGS 妊娠日粮和 30% DDGS 泌乳日粮，两种日粮均含有 100 ppm 硫酸锌补充锌；4）DDGS/PSZn-玉米-豆粕-40% DDGS 妊娠日粮和 30% DDGS 泌乳日粮，两种日粮均含有 100 ppm 锌多糖复合物补充锌。用一部分母猪（n = 20）进行第五种日粮处理，以确定不补充锌时，饲喂玉米-豆粕基础日粮的妊娠和泌乳母猪的基础锌损失。在妊娠和泌乳期进行养分平衡试验，以评估四种日粮处理组中锌源的消化率，并确定不提供补充锌时的基础锌损失。统计模型包括日粮、锌源及其相互作用的固定效应，以及胎次的随机效应。估计的内源性锌损失用于调整四种日粮处理平衡期锌的表观全肠道消化率（ATTD）至真实全肠道消化率（TTTD）。在试验的任何时间，处理之间尿液、血浆、初乳和牛奶样本中的锌浓度均无差异（P > 0.05）。与对照处理组相比，饲喂 DDGS/PSZn 的妊娠母猪的 ATTD、TTTD 和锌的总体保留率提高（P < 0.05），而 DDGS/ZnSO4 处理组的反应处于中间水平。不食用 DDGS 且补充锌多糖复合物的泌乳母猪的 ATTD、TTTD 和锌保留率最高（P < 0.05），这与妊娠时的反应相反。此外，饲喂 DDGS/PSZn 的泌乳母猪的 ATTD、TTTD 和锌保留率均低于其他所有处理组（P < 0.05）。总的来说，锌多糖复合物和硫酸锌的锌消化率似乎受到繁殖周期阶段和 DDGS 中膳食纤维的影响。
