The experiment was conducted to investigate the effect of supplementary zinc-threonine (Zn-Thr), zinc-methionine (Zn-Met), and zinc oxide (ZnO) on the laying performance, egg quality, Zn content in egg and excreta. One hundred and sixty hens (Hy-Line W36) were randomly divided into 10 treatments with 4 replications of 4 hens each. During the first 4 weeks, groups were fed a corn-soy basal diet without extra zinc (30.3 mg Zn/kg diet) to depletion storage zinc from the body and it was used as the control diet. During the ensuing 10 weeks from 36 to 45 weeks of age, 3 levels of 30, 60, and 90 mg Zn/kg were added to the diet by ZnO, Zn-Met, and Zn-Thr sources. Results showed that there were no significant differences between the experimental treatments in terms of egg weight, feed intake, eggshell weight, eggshell percentage, and albumen weight. In total experimental period, the supplementation of Zn-Met and Zn-Thr decreased feed conversion ratio and increased egg mass and egg production compared with ZnO 30 and 60 mg Zn/kg and control treatments (P < 0.05). The results showed that treatment effect on Zn content in egg and excreta was significant (P < 0.05). It is concluded that diets supplied with lower levels of organic Zn can maintain egg production performance, improve egg quality, enrich eggs, increase bioavailability, and reduce the negative effects of age on egg quality characteristics in laying hens compared with their oxide form.

中文翻译：

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比较 Zn-苏氨酸、Zn-蛋氨酸和氧化锌对蛋鸡的性能、蛋质量、锌生物利用度以及蛋和蛋鸡排泄物中的锌含量。

本试验旨在研究补充苏氨酸锌（Zn-Thr）、蛋氨酸锌（Zn-Met）和氧化锌（ZnO）对产蛋性能、蛋品质、蛋和排泄物中锌含量的影响。160 只母鸡 (Hy-Line W36) 随机分为 10 个处理，每组 4 只母鸡，重复 4 次。在前 4 周，各组喂食不含额外锌的玉米大豆基础日粮（30.3 毫克锌/公斤日粮）以消耗体内储存的锌，并将其用作对照日粮。在随后的 36 至 45 周龄的 10 周内，通过 ZnO、Zn-Met 和 Zn-Thr 源将 30、60 和 90 mg Zn/kg 三种水平添加到饮食中。结果表明，试验处理之间在蛋重、采食量、蛋壳重量、蛋壳百分比和蛋白重量方面没有显着差异。在整个试验期间，与ZnO 30和60 mg Zn/kg和对照处理相比，Zn-Met和Zn-Thr的添加降低了饲料转化率，增加了产蛋量和产蛋量（P < 0.05）。结果表明，处理对鸡蛋和排泄物中锌含量的影响显着（P < 0.05）。结论是，与氧化物形式相比，饲喂有机锌含量较低的日粮可以保持产蛋性能、提高蛋质量、丰富蛋液、提高生物利用度，并减少年龄对蛋鸡蛋品质特性的负面影响。结果表明，处理对鸡蛋和排泄物中锌含量的影响显着（P < 0.05）。结论是，与氧化物形式相比，饲喂有机锌含量较低的日粮可以保持产蛋性能、提高蛋质量、丰富蛋液、提高生物利用度，并减少年龄对蛋鸡蛋品质特性的负面影响。结果表明，处理对鸡蛋和排泄物中锌含量的影响显着（P < 0.05）。结论是，与氧化物形式相比，饲喂有机锌含量较低的日粮可以保持产蛋性能、提高蛋质量、丰富蛋液、提高生物利用度，并减少年龄对蛋鸡蛋品质特性的负面影响。