Khairunnesa Most, Kumar Alip, Gharib-Naseri Kosar, Choct Mingan, Barekatain Reza, Wu Shu-Biao
School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.
SARDI Roseworthy campus, University of Adelaide, SA 5371, Australia.
Poult Sci. 2025 Jul 13;104(10):105574. doi: 10.1016/j.psj.2025.105574.
Bacillus-based probiotics and dietary enzymes have gained attention for supporting gut health, nutrient digestion, and intestinal integrity in poultry. This study evaluated the effects of Bacillus subtilis PB6 (Pb) and xylanase (Xy), individually and in combination, on the performance, intestinal lesions, and histomorphology of broiler chickens challenged with subclinical necrotic enteritis (SNE). A total of 630-d-old, mixed-sex Cobb 500 broilers were utilized in a 2 × 2 + 1 factorial arrangement of treatments: NE challenge without additives (CC); NE challenge with Xy at 0.03 % (Xy); NE challenge with Pb at 0.05 % (Pb); NE challenge with Xy at 0.03 % and Pb at 0.05 % (Xy+Pb); and, a non-challenge, additive free control (NC). In the pre-challenge period, birds in NC and CC groups were considered a control. A significant Xy × Pb interaction was observed for body weight gain (BWG) (P < 0.01) and FCR (P < 0.05) before challenge (d0-8). Pb efficacy for reducing FCR was significant without Xy supplementation, while Xy enhanced BWG without Pb (P < 0.01). During d9-19, all challenged birds showed reduced BWG (P < 0.05) and increased FCR (P < 0.05) compared to NC birds. During d20-35 and d0-35, Pb significantly improved FCR and reduced feed intake (FI) as the main effect among challenged birds (P < 0.05), equating the performance of NC birds (P > 0.05). NE challenge increased (P < 0.05) duodenal lesions in females but not males. A significant Xy × Pb interaction (P < 0.05) was observed for villus height (VH) and the VH to crypt depth (CD) ratio. Pb enhanced VH and VH/CD (P < 0.05) only when Xy was not supplemented. Furthermore, Pb-fed birds showed a trend towards increased villus surface area (VSA) (P = 0.067). In conclusion, Pb improves feed efficiency and mitigates the adverse effects of SNE-induced damage to intestinal health, while Xy enhances pre-challenge growth without augmenting Pb's benefits during NE.
基于芽孢杆菌的益生菌和膳食酶因有助于家禽肠道健康、营养消化和肠道完整性而受到关注。本研究评估了枯草芽孢杆菌PB6（Pb）和木聚糖酶（Xy）单独及联合使用对受亚临床坏死性肠炎（SNE）攻击的肉鸡的生产性能、肠道病变和组织形态学的影响。总共630只1日龄的混合性别的科宝500肉鸡被用于2×2 + 1析因处理安排：无添加剂的SNE攻击组（CC）；0.03% Xy的SNE攻击组（Xy）；0.05% Pb的SNE攻击组（Pb）；0.03% Xy和0.05% Pb的SNE攻击组（Xy+Pb）；以及无攻击、无添加剂的对照组（NC）。在攻击前阶段，NC组和CC组的鸡被视为对照组。在攻击前（第0 - 8天），观察到体重增加（BWG）（P < 0.01）和料重比（FCR）（P < 0.05）存在显著的Xy×Pb交互作用。在不添加Xy的情况下，Pb降低FCR的效果显著，而在不添加Pb的情况下，Xy提高了BWG（P < 0.01）。在第9 - 19天，与NC组鸡相比，所有受攻击的鸡的BWG均降低（P < 0.05），FCR均升高（P < 0.05）。在第20 - 35天和第0 - 35天，Pb作为受攻击鸡中的主要效应显著改善了FCR并降低了采食量（FI）（P < 0.05），使其生产性能与NC组鸡相当（P > 0.05）。SNE攻击使雌性鸡的十二指肠病变增加（P < 0.05），但雄性鸡未增加。在绒毛高度（VH）和VH与隐窝深度（CD）比值方面观察到显著的Xy×Pb交互作用（P < 0.05）。仅在不添加Xy时，Pb提高了VH和VH/CD（P < 0.05）。此外，饲喂Pb的鸡有绒毛表面积（VSA）增加的趋势（P = 0.067）。总之，Pb提高了饲料效率并减轻了SNE对肠道健康造成的损害的不利影响，而Xy在攻击前提高了生长速度，但在SNE期间并未增强Pb的益处。
