Department of Animal Biosciences, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Livalta, AB Agri Ltd., Peterborough, Cambridgeshire, PE2 6FL, UK.
J Anim Sci. 2022 Apr 1;100(4). doi: 10.1093/jas/skac094.
Growth performance and physiological responses of nursery piglets when fed enzymatically treated yeast (HY40) and pharmacological ZnO alone or in combination were investigated. A total of 144 pigs (21 d old, BW 7.32 ± 0.55 kg) were placed in 36 pens (4 pigs/pen). Pigs were randomly assigned to one of four dietary treatments (n = 9): 1) control corn-wheat-soybean meal diet (control), 2) control + HY40 (HY40), 3) control + (ZnO) and 4) control + HY40 + ZnO (HY40+ZnO). Inclusion of HY40 and ZnO was 0.5% and 3,000 ppm in phase I (days 0 to 14), respectively, and halved in phase II (days 15 to 42). All diets contained 0.2% TiO2 for determination of apparent total tract digestibility (ATTD) of components. Body weight and feed disappearance were recorded weekly. One pig per pen was killed for organ weights, blood, and tissue samples on day 14. Except for phase II, when HY40 + ZnO pigs had greater average daily feed intake (P = 0.004) than all other treatments, there were no (P > 0.05) interactions between HY40 and ZnO on growth performance. Pigs fed HY40 or ZnO containing diets were heavier (P < 0.05) than pigs fed without by the end of the study. On day 14, pigs fed additives exhibited higher (P ≤ 0.009) ATTD of dry matter (DM) and gross energy (GE) than control pigs. On day 28, pigs fed control, HY40, and HY40 + ZnO had greater (P ≤ 0.022) ATTD of DM, crude protein, and GE than piglets fed ZnO only. Pigs fed HY40 + ZnO had lower ileal digesta Escherichia coli concentration (P < 0.05) than HY40 and control pigs. Ileal digesta of pigs fed ZnO diets had higher lactobacillus to E. coli ratio (1.44 vs. 1.20; P = 0.001), exhibited higher concentrations of acetic (P = 0.01) and butyric acid (P = 0.01) but lower lactic (P = 0.02) and total short chain fatty acids (P = 0.033) than pigs fed non-ZnO diets. Greater (P < 0.05) mRNA expression of nutrient transporters, tight junction proteins, and fecal excretion of zinc (Zn) was observed in ZnO pigs relative to non-ZnO pigs. Pigs fed HY40 diets had greater (P = 0.002) villus height to crypt depth ratio (VH:CD) than non-HY40 pigs. The concentration of plasma IgA was higher (P = 0.04) in HY40 + ZnO pigs relative to other pigs, whereas HY40 pigs showed higher (P < 0.001) jejunal IgA than non-HY40 pigs. Although the mode of action of HY40 and ZnO differed, the present study indicated that HY40 improved growth performance and jejunal function and immunity, making HY40 an effective alternative to pharmacological ZnO in nursery pigs feeding programs.
本研究旨在探究在单独或联合使用酶处理酵母（HY40）和药理学氧化锌（ZnO）的情况下，保育猪的生长性能和生理反应。将 144 头 21 日龄、体重 7.32±0.55kg 的仔猪随机分配到 36 个围栏（每栏 4 头）中，然后分别投喂以下四种日粮：1）对照玉米-小麦-豆粕日粮（对照），2）对照+HY40（HY40），3）对照+（ZnO）和 4）对照+HY40+ZnO（HY40+ZnO）。在第一阶段（0-14 天），HY40 和 ZnO 的添加量分别为 0.5%和 3000ppm，第二阶段（15-42 天）减半。所有日粮均含有 0.2%的 TiO2，用于测定各成分的表观全肠道消化率（ATTD）。每周记录体重和饲料消耗量。在第 14 天，每栏随机选择一头猪进行器官重量、血液和组织样本采集。除了第二阶段，添加 HY40+ZnO 的猪比其他处理组的平均日采食量更高（P=0.004），其他阶段，HY40 和 ZnO 对生长性能没有（P＞0.05）交互作用。添加 HY40 或 ZnO 的日粮组猪在研究结束时比未添加的猪更重（P＜0.05）。在第 14 天，添加添加剂的猪的干物质（DM）和总能（GE）的 ATTD 高于对照组猪（P≤0.009）。在第 28 天，与仅投喂 ZnO 的仔猪相比，投喂对照、HY40 和 HY40+ZnO 的猪的 DM、粗蛋白和 GE 的 ATTD 更高（P≤0.022）。投喂 HY40+ZnO 的猪的回肠食糜中大肠杆菌浓度较低（P＜0.05），而 HY40 和对照组猪的回肠食糜中大肠杆菌浓度较高。投喂 ZnO 日粮的猪的回肠食糜中乳酸菌与大肠杆菌的比例更高（1.44 比 1.20；P=0.001），乙酸（P=0.01）和丁酸（P=0.01）浓度更高，乳酸（P=0.02）和总短链脂肪酸（P=0.033）浓度更低，而未投喂 ZnO 的猪的回肠食糜中乙酸（P=0.01）和丁酸（P=0.01）浓度更高，乳酸（P=0.02）和总短链脂肪酸（P=0.033）浓度更低。与未投喂 ZnO 的猪相比，投喂 ZnO 日粮的猪的营养转运体、紧密连接蛋白和粪便锌排泄的 mRNA 表达更高（P＜0.05）。投喂 HY40 日粮的猪的绒毛高度与隐窝深度比（VH:CD）高于未投喂 HY40 的猪（P=0.002）。与其他猪相比，投喂 HY40+ZnO 的猪的血浆 IgA 浓度更高（P=0.04），而投喂 HY40 的猪的空肠 IgA 浓度高于未投喂 HY40 的猪（P＜0.001）。尽管 HY40 和 ZnO 的作用模式不同，但本研究表明，HY40 可以改善生长性能和空肠功能及免疫，是保育猪饲养方案中 ZnO 的有效替代品。
