PDF(Pubmed)
Abstract：
Pressure to reduce the use of antibiotics in the poultry industry has intensified research on alternative solutions to support intestinal health, including but not limited to direct fed microbials (DFM). Heat stress is known to impact intestinal health and function. The aim of this study was to determine efficacy of a water applied DFM product on broiler performance during the summer period. One of two treatments were randomly allocated to 12 replicate floor pens each: a control treatment and a treatment provided daily with a dual strain DFM comprised of Lactobacillus acidophilus AG01 and Bifidobacterium animalis AG02 at 1 × 108 CFU/bird/d. Each pen contained 20 Ross 308 broilers. All birds were fed the same three-phased wheat- and soybean meal-based diets. Body weight, feed intake, feed conversion ratio, and mortality were measured at d 0, 10, 24, 35, and 42. Due to natural extreme external temperature conditions, all birds were subject to heat stress during the end of the grower phase up to and including the finisher phase. Temperature was on average 5°C higher compared to industry recommendation. No significant differences were found in growth performance between the control and DFM treatment, yet BW at d 42 in both treatments was reduced by 19% compared to the breed standard. The DFM treatment significantly reduced mortality among the birds. Overall mortality from d 1 to d 35 was reduced from 4.58% to 0.42% (P = 0.023) and overall mortality from d 1 to d 42 was reduced from 5.83 to 0.83% (P = 0.027). This was driven by the difference in heat-stress related mortality in the finisher phase from d 25 to d 42, where mortality reached only 0.44% in the DFM treatment versus 2.88% in the unsupplemented control treatment. Post-mortem analysis confirmed heat-stress related hypoxia. In conclusion, the dual strain DFM may have provided improved (intestinal) homeostasis and barrier function allowing increased resilience to heat stress in broilers.
摘要：
家禽业减少抗生素使用的压力加强了对支持肠道健康的替代解决方案的研究，包括但不限于直接饲喂微生物(DFM)。已知热应激影响肠道健康和功能。这项研究的目的是确定夏季期间水施用的DFM产品对肉鸡性能的功效。将两种处理中的一种随机分配到12个重复的地板围栏中：对照处理和每天提供的双菌株DFM处理，该双菌株DFM由嗜酸乳杆菌AG01和动物双歧杆菌AG02组成，剂量为1×108CFU/鸟/d。每笔包含20只罗斯308只肉鸡。所有禽类都饲喂相同的三阶段小麦和大豆粉饮食。体重,饲料摄入量，饲料转化率，在第0、10、24、35和42天测量死亡率。由于自然极端的外部温度条件，所有鸟类在生长阶段结束时都会受到热应激，直到包括完成阶段。与行业推荐相比,温度平均高5°C。对照和DFM处理之间的生长性能没有显着差异，然而，与品种标准相比，两种处理在第42天的BW降低了19%。DFM处理显著降低了禽类的死亡率。第1天至第35天的总死亡率从4.58%降至0.42%(P=0.023)，第1天至第42天的总死亡率从5.83%降至0.83%(P=0.027)。这是由第25天至第42天的修整期与热应激相关的死亡率差异驱动的，其中DFM治疗的死亡率仅为0.44％，而未补充的对照治疗的死亡率为2.88％。验尸分析证实了热应激相关的缺氧。总之,双菌株DFM可以提供改善的(肠)体内平衡和屏障功能,允许增加肉鸡对热应激的恢复力。
