Abstract This study assessed the effects of three tannin-based feed additives on the productive performance, foot-pad conditions, plasma metabolome, and caecal microbiota of meat-type chickens. A total of 2,340 male broilers were divided into 4 treatments (9 replicates each) fed either a commercial basal diet (CON) or the basal diet supplemented with one of the three tested products (A, B, or C) up to 49 days. According to manufacturers’ instructions, product A was added to the basal diet at 0.3% from 0 to 49 d, while B and C at 0.13% from 0 to 21 d and 0.12% from 22 to 49 d. Compared to CON, tannin-supplemented birds consumed less feed (6.59 vs. 6.37, 6.49, and 6.35 kg, for CON vs. A, B, and C, respectively; p < .001) and reached a lower slaughter weight (3,599 vs. 3,494, 3,546, and 3,472 g, for CON vs. A, B, and C, respectively; p < .05). Feed conversion ratio (FCR) was not affected by the tannin supplementations, except for the starter phase when CON exhibited lower FCR than the other groups (p < .01). The observed differences in the plasma metabolome between CON and treated groups might indicate an impaired energy metabolism of tannin-supplemented chickens. The significant reduction in the caecal microbial diversity and short-chain fatty acid producer bacteria can also be related to the depressed performance of tannin-fed chickens. In contrast to earlier findings, pododermatitis was unaffected by our treatments. Further dose-response studies can help better exploit tannin-based additives in broiler diets. Highlights Two tannin-based feed additives out of the three tested in this study significantly reduced feed intake and body weight gain of broiler chickens. The tannin-produced shifts in the plasma metabolome and caecal microbiota may have been two reasons for the productive performance depression. Further dose-response trials can help the poultry industry to better elucidate the role of tannins as feed supplements for broiler chickens.

中文翻译：

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肉鸡中单宁基饲料添加剂作用模式的洞察：寻找与血浆代谢组和盲肠微生物群的联系

摘要 本研究评估了三种基于单宁的饲料添加剂对肉鸡生产性能、足垫条件、血浆代谢组和盲肠微生物群的影响。总共 2,340 只雄性肉鸡被分成 4 个处理（每个 9 个重复），分别饲喂商业基础日粮 (CON) 或补充了三种测试产品（A、B 或 C）之一的基础日粮，最长 49 天。根据制造商的说明，产品A在0至49天添加0.3%，而B和C在0至21天添加0.13%，在22至49天添加0.12%。与 CON 相比，添加单宁的鸡只消耗更少的饲料（CON 与 A、B 和 C 分别为 6.59 与 6.37、6.49 和 6.35 公斤；p < .001）并达到较低的屠宰重量（3,599 与. 3,494、3,546 和 3,472 g，对于 CON 与 A、B 和 C，分别为；p < .05）。饲料转化率 (FCR) 不受单宁补充剂的影响，除了起始阶段 CON 表现出低于其他组的 FCR (p < .01)。观察到的 CON 组和治疗组之间血浆代谢组的差异可能表明添加单宁的鸡的能量代谢受损。盲肠微生物多样性和短链脂肪酸生产菌的显着减少也可能与单宁喂养鸡的性能下降有关。与早期的发现相反，足皮炎不受我们的治疗影响。进一步的剂量反应研究可以帮助更好地利用肉鸡日粮中的单宁添加剂。亮点 本研究中测试的三种基于单宁的饲料添加剂中的两种显着降低了肉鸡的采食量和体重增加。单宁产生的血浆代谢组和盲肠微生物群的变化可能是生产性能下降的两个原因。进一步的剂量反应试验可以帮助家禽业更好地阐明单宁作为肉鸡饲料补充剂的作用。