Novus do Brasil Com. e Imp. Ltda, Indaiatuba, SP, Brazil.
Centro de Tecnologia Animal Ltda, Domingos Martins, Espírito Santo, ES, Brazil.
J Anim Sci. 2019 Oct 3;97(10):4242-4247. doi: 10.1093/jas/skz282.
Two performance studies were conducted to investigate the effects of 3 different sources of Cu on production parameters of piglets. A total of 256 piglets weaned at 24 ± 2 d were randomly allocated into 4 treatments with 10 or 8 replicates per treatment of 4 or 3 piglets per pen in Exp. 1 and 2, respectively. The experimental period was divided into 3 feeding phases: Phase 1 (24 to 35 d), Phase 2 (36 to 49 d), and Phase 3 (50 to 70 d). Treatments included a Control group (fed 10 mg/kg of Cu from CuSO4), a group fed 160 mg/kg of either CuSO4 (CuSO4-160) or tri-basic copper chloride (TBCC), and a group fed Cu methionine hydroxy analogue chelated (Cu-MHAC) at 150, 80, and 50 mg/kg in Phases 1, 2, and 3, respectively. The methionine value of Cu-MHAC was accounted during diet formulation to achieve the same levels of methionine across treatments. Phases 1 and 2 diets contained 2,200 and 1,500 ppm of ZnO, respectively; and antibiotics were used as growth promoters. Performance parameters were analyzed as completely randomized block design, in which each experiment was considered as a block. In trial 2, blood serum and mucosal samples, from the fundic region of the stomach, were collected from 1 piglet per replicate at day 70 and tested for serum growth hormone levels (GH) and ghrelin mRNA expression, respectively. The contrast between Cu-MHAC vs. CuSO4-160 + TBCC showed that piglets fed Cu-MHAC exhibited better feed conversion ratio (FCR) in all feeding phases compared with feeding inorganic Cu (P < 0.05). Overall, feeding Cu-MHAC improved body weight (BW), BW gain, feed intake (FI), and FCR vs. Control diet fed piglets; yet, it improved BW and FCR vs. TBCC fed piglets, and improved BW, BW gain, and FI vs. CuSO4-160 fed piglets (P < 0.05). Feeding TBCC promoted similar performance than feeding CuSO4-160, regardless of age (P > 0.05). Both ghrelin expression and growth hormone serum levels were significantly increased by feeding Cu-MHAC vs. Control diet fed animals (P < 0.01). Feeding CuSO4-160 upregulated ghrelin expression vs. Control (P < 0.01) while GH serum levels and ghrelin expression did no change by feeding TBCC compared with Control diet fed animals (P > 0.05). It was concluded that feeding Cu-MHAC at the levels tested herein can improve growth performance of piglets beyond feeding 160 ppm of either CuSO4 or TBCC, which may be partially explained by the increased expression of ghrelin and GH serum levels.
进行了两项性能研究，以调查三种不同来源的 Cu 对仔猪生产参数的影响。共有 256 头 24±2 日龄断奶的仔猪被随机分配到 4 个处理中，每个处理有 10 或 8 个重复，每个重复有 4 或 3 头仔猪/圈舍，分别在实验 1 和 2 中进行。实验期分为 3 个饲养阶段：第 1 阶段（24 至 35 天）、第 2 阶段（36 至 49 天）和第 3 阶段（50 至 70 天）。处理包括对照组（饲喂 10mg/kg 的 Cu 来自 CuSO4）、饲喂 160mg/kg 的 CuSO4（CuSO4-160）或三碱式氯化铜（TBCC）的组，以及在第 1、2 和 3 阶段分别以 150、80 和 50mg/kg 饲喂 Cu 蛋氨酸羟基类似物螯合物（Cu-MHAC）的组。在配方中考虑了 Cu-MHAC 的蛋氨酸值，以确保在所有处理中达到相同的蛋氨酸水平。第 1 和第 2 阶段的日粮分别含有 2200 和 1500ppm 的 ZnO；并且使用抗生素作为生长促进剂。性能参数作为完全随机区组设计进行分析，其中每个实验都被视为一个区组。在试验 2 中，从每个重复的 1 头仔猪中收集胃底区的血清和黏膜样本，分别在第 70 天检测血清生长激素水平（GH）和胃饥饿素 mRNA 表达。Cu-MHAC 与 CuSO4-160+TBCC 的对比表明，与饲喂无机 Cu 的仔猪相比，饲喂 Cu-MHAC 的仔猪在所有饲养阶段的饲料转化率（FCR）都更好（P<0.05）。总体而言，与对照日粮相比，饲喂 Cu-MHAC 的仔猪的体重（BW）、BW 增重、采食量（FI）和 FCR 均有所提高；然而，与 TBCC 相比，BW 和 FCR 有所提高，与 CuSO4-160 相比，BW、BW 增重和 FI 有所提高（P<0.05）。与饲喂 CuSO4-160 相比，无论年龄大小，饲喂 TBCC 均能促进相似的性能（P>0.05）。与对照日粮相比，饲喂 Cu-MHAC 可显著增加胃饥饿素表达和生长激素血清水平（P<0.01）。与对照相比，饲喂 CuSO4-160 可上调胃饥饿素表达（P<0.01），而与对照日粮相比，饲喂 TBCC 对 GH 血清水平和胃饥饿素表达没有影响（P>0.05）。综上所述，与饲喂 160ppm 的 CuSO4 或 TBCC 相比，在此处测试的水平下饲喂 Cu-MHAC 可以提高仔猪的生长性能，这可能部分解释为胃饥饿素和 GH 血清水平表达增加。
