Abstract：
Leg disorders have become increasingly common in broilers, leading to lower meat quality and major economic losses. This study evaluated the effects of dietary supplementation with Clostridium butyricum (C. butyricum) and 25-hydroxyvitamin D3 (25-OH-D3) on bone development by comparing growth performance, tibial parameters, Ca and P contents of tibial ash, bone development-related indicators\' level, and cecal short-chain fatty acids in Cobb broilers. All birds were divided into four treatment groups, which birds fed either a basal diet (Con), basal diet + 75 mg chlortetracycline/kg (Anti), basal diet + C. butyricum at 109 CFU/kg (Cb), basal diet + C. butyricum at 109 CFU/kg and 25-OH-D3 at 25 μg/kg (CbD), or basal diet + 25-OH-D3 at 25 μg/kg (CD). Our results suggest that the dietary supplementation in Cb, CbD, and CD significantly increased the body weight (BW) and average daily gain (ADG), and reduced the feed-to-weight ratio (F/G) at different stages of growth (P < 0.05). Dietary supplementation in Cb, CbD, and CD prolonged (P < 0.05) the behavioral responses latency-to-lie (LTL) time, reduced (P < 0.05) the levels of osteocalcin (BGP) and peptide tyrosine (PYY), and increased (P < 0.05) serotonin (5-HT) and dopamine (DA). Treatment with Cb increased (P < 0.05) the levels of acetic acid, isobutyric acid, butyric acid, and isovaleric acid compared with those in Con group. The cecal metagenome showed that Alistipes spp. were significantly more abundant in Cb, CbD, and CD groups (P < 0.05). A total of 12 metabolic pathways were significantly affected by supplementation, including the signaling pathways of glucagon, insulin, and PI3K-AKT; primary and secondary bile acid biosynthesis; and P-type Ca 2+ transporters (P < 0.05). Hence, the CbD supplementation modulates bone metabolism by regulating the mediators of gut-brain axis, which may inform strategies to prevent leg diseases and improve meat quality in broilers.
摘要：
腿部疾病在肉鸡中变得越来越普遍，导致肉质下降和重大经济损失。这项研究评估了饮食中添加丁酸梭菌（C.通过比较生长性能，丁酸）和25-羟基维生素D3（25-OH-D3）对骨骼发育的影响，胫骨参数,胫骨灰中Ca、P含量,骨发育相关指标水平，和Cobb肉鸡的盲肠短链脂肪酸。将所有鸟类分为四个治疗组，哪些鸟类喂食基础饮食(Con)，基础饮食+75毫克金霉素/千克（抗），基础饮食+109CFU/kg(Cb)的丁酸梭菌，基础饮食109CFU/kg的丁酸梭菌和25μg/kg的25-OH-D3（CbD），或基础饮食25-OH-D3，25μg/kg（CD）。我们的结果表明，Cb中的膳食补充剂，CbD,和CD显着增加体重（BW）和平均日增重（ADG），并降低了不同生长阶段的饲料重量比（F/G）（P<0.05）。Cb的膳食补充剂，CbD,和CD延长（P<0.05）行为反应潜伏期说谎（LTL）时间，降低骨钙蛋白(BGP)和肽酪氨酸(PYY)水平(P<0.05),5-羟色胺（5-HT）和多巴胺（DA）升高（P<0.05）。用Cb处理增加了乙酸的水平（P<0.05），异丁酸,丁酸,和异戊酸与Con组相比。盲肠宏基因组显示Alistipesspp。在Cb中明显更丰富，CbD,与CD组比较(P<0.05)。共有12个代谢途径受到补充的显著影响，包括胰高血糖素的信号通路，胰岛素，和PI3K-AKT；初级和次级胆汁酸生物合成；和P型Ca2转运蛋白（P<0.05）。因此，补充CbD通过调节肠-脑轴的介质来调节骨代谢，这可能为预防肉鸡腿部疾病和改善肉质的策略提供信息。
