Nutrition Department, Desert Research Center, Mataria, Cairo, Egypt.
Genetics Department, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.
Sci Rep. 2024 Oct 25;14(1):25411. doi: 10.1038/s41598-024-75533-8.
This study investigates the role of dietary Bacillus subtilis and oregano essential oil in mitigating the effects of high stocking density on growth performance, carcass traits, physiological stress indicators, gene expression, and intestinal integrity in broiler chickens. A total of, 1250 one-day-old Ross 308 male broiler chicks were randomly allocated to five experimental groups, where each group had five replicates of 50 chicks. Group 1 (control, LSD): 15 chicks/m fed a basal diet without feed additive, group 2 (HSD): 20 chicks/m fed a basal diet without feed additive, group 3 (BHSD): 20 chicks/m fed a basal diet supplemented with B. subtilis (500 mg/kg diet), group 4 (OHSD): 20 chicks/m fed a basal diet supplemented with oregano essential oil (300 mg/kg diet), group 5 (CHSD): 20 chicks/m fed a basal diet supplemented with oregano essential oil and B. subtilis. At 35 days of age, there was a noticeable improvement in the growth performance of broilers fed CHSD under high stocking density through the increase in body weight gain, dressing percentage, and crude protein digestibility with a decrease in feed conversion rate compared to other groups. Adding CHSD enhanced the state of oxidation and immunity through increasing superoxide dismutase, glutathione peroxidase, and the relative weight of bursa of Fabricius, while decreasing malondialdehyde, in addition to increasing plasma triiodothyronine levels. The microbial structure and morphometric parameters improved in the group that received the CHSD compared to the other groups, where villus height and Lactobacillus population increased, whereas Escherichia coli and Clostridium perfringens population decreased. Glucose transporter 2 (GLUT2), fatty acid transporter 1 (FABP1), and amino acid transferase 1 (CAT1) gene expression levels significantly increased when feeding on oregano essential oil with B. subtilis. In conclusion, combining oregano essential oil and B. subtilis supplements mitigated the effects of high stocking density by enhancing growth performance, antioxidative status, and intestinal integrity, in addition to modifying the genetic expression of genes related to nutrient absorption.
本研究探讨了日粮枯草芽孢杆菌和牛至精油在减轻高密度饲养对肉鸡生长性能、胴体特性、生理应激指标、基因表达和肠道完整性影响中的作用。将 1250 只 1 日龄罗斯 308 雄性肉鸡随机分配到 5 个实验组中，每个组有 5 个重复，每个重复 50 只鸡。第 1 组（对照，LSD）：15 只鸡/m2，饲喂基础日粮，不添加饲料添加剂；第 2 组（HSD）：20 只鸡/m2，饲喂基础日粮，不添加饲料添加剂；第 3 组（BHSD）：20 只鸡/m2，饲喂基础日粮，添加 500mg/kg 日粮的枯草芽孢杆菌；第 4 组（OHSD）：20 只鸡/m2，饲喂基础日粮，添加 300mg/kg 日粮的牛至精油；第 5 组（CHSD）：20 只鸡/m2，饲喂基础日粮，添加牛至精油和枯草芽孢杆菌。在 35 日龄时，高密度饲养条件下，与其他组相比，饲喂 CHSD 的肉鸡体重增加、屠宰率提高、粗蛋白消化率提高、料肉比降低，生长性能明显改善。添加 CHSD 通过提高超氧化物歧化酶、谷胱甘肽过氧化物酶和法氏囊相对重量，降低丙二醛水平，同时提高血浆三碘甲状腺原氨酸水平，增强了氧化和免疫状态。与其他组相比，CHSD 组的微生物结构和形态计量参数得到改善，其中绒毛高度和乳酸杆菌数量增加，而大肠杆菌和产气荚膜梭菌数量减少。添加牛至精油和枯草芽孢杆菌后，葡萄糖转运体 2（GLUT2）、脂肪酸转运蛋白 1（FABP1）和氨基酸转移酶 1（CAT1）基因的表达水平显著增加。综上所述，结合牛至精油和枯草芽孢杆菌补充剂可通过提高生长性能、抗氧化状态和肠道完整性来减轻高密度饲养的影响，同时还可以改变与营养吸收相关的基因的遗传表达。
